Sunday, August 31, 2008

27 comments:
TRIPLE THREAT...3 LANDFALLS?
Sunday 8-31 Evening Update

Gustav Growing

(Storm clouds build over Havana, Cuba as Gustav approached from the south)

GUSTAV: 10 PM Sunday Analysis. It's a forgone conclusion that landfall as a Category 3 is now just a matter of time. It appears from latest satellite and radar imagery that a slightly discernable northward jog is occuring, which is very troubling. I also notice the Central Dense Overcast seems to be wrapping around a reforming eye. This indicates strengthening and unless the storm slows overnight, we could wake up to an intensifying 3 in the 125-130 mph range about to make landfall. Remember that each mile Gustav nudges east of the official track makes the damage to New Orleans, Lake Ponchartrain and surrounding areas that much worse. A surge of 10-14 feet traveling up the Mississippi River will overwhelm levee areas that were not affected in the same way as in Katrina. Water is again going to surge into the lake, and probably already has. It is at least reassuring to see the highways leading out of the city empty this afternoon, unlike last time. With a slowing of forward speed forecast near and after landfall, the flooding and rainfall impact of this may be worse than Katrina, and over a larger area. I submit that those who claim a westward track is better for New Orleans than Katrina's eastward jog are following wishcasting or don't understand the true nature of water movement under a long duration fetch of wind. This will be catastrophic any way you slice it. Below is my probably the last image of Gustav I will before landfall..as of 10:30 PM 8-31-08.

Gustav in the Gulf 3

HANNA: A SURPRISE FOR STUDENTS? Until Monday, the projected path is an easy bet..west toward the Bahamas, then it gets complicated. The high pressure ridge that will build into the Northeast this week is going to influence her direction in the medium range. This in combination with Gustav's outflow may even weaken the storm somewhat. Once Gustav moves into Texas and the ridge in the Northeast moves offshore by Friday, divergent flow created by the departing High may provide Hanna with an "out." Tropical cyclones, just like air, water and school students, like to follow the path of least resistance. What looks more likely now is a recurvature east of Florida, with a landfall in the Carolinas. If Hanna is traveling north or northeast by then, the southern Chesapeake Bay, tidewater Virginia and the DelMarVa peninsula are put into play for secondary landfall by the weekend. Also note by that time, Hanna will be entering the westerlies, and thus forward speed will increase significantly. I've seen before a number of times where a fast moving system on such a track led to Tropical Storm Warnings for the entire Chesapeake Bay. While it may seem premature to say this, that raises the specter of disruption to the school schedule this coming Friday for at least many schools in Eastern North Carolina and even southeast Virginia. A stronger storm at landfall that moves more quickly will impact schools from Washington DC north and east into New Jersey. If history is any guide, many Mid-Atlantic schools closed for similar track storms (though not similar intensity) such as Gloria in 1985, Floyd in 1999, and the new historical indicator storm for Maryland-- Isabel in 2003.


Hanna Computer Tracks 1

IKE: THIS ONE YOU WON'T LIKE. Currently pegged as "Invest AL97" and located now west of the Cape Verde Islands, this next long track storm has climatology on it's side, along with favorable easterlies and thousands of miles of warm Atlantic waters. I'll be among the first to say this storm has potential to affect a wide area, so I'm sure many weatherfolk from the Gulf Coast to Florida to the Mid-Atlantic are already watching this storm's every move. One thing for sure, if it continues on a westward track, we will have a new round of major headlines in another 8-10 days after we get done with Hanna.

Invest 97L Track 2

For details on all these systems, visit this high quality tracking site: stormpulse.com or view the National Hurricane Center's main page.

Friday, August 29, 2008

2 comments:
LEST WE FORGET

Less We Forget 1

Three years ago, the worst case scenario became a reality. The predictions came true, the projections were justified and the suffering of a city and the people it left behind became inhuman. For years, some said that someday, the luck would run out in the Crescent City. Others claimed we were safe behind our technology and devices. The levees will hold, the pumps will work. Leaders made it look like we were ready when really, it wasn't even close. And now today, it looks like all hands are finally on deck to salvage the good work that's happened in these three long years. Friday, August 29, 2008 saw the final burial of 80 victims from "the storm" whom were never claimed, except together by God and Nature's wrath on that fateful day. Today, those 80 souls among a thousand or more look upon us and whisper ever so quietly in the late night breeze wafting across the wetlands... "Lest We Forget." Waiting to see if perhaps this time, we have learned the lesson, so that their lives and unhappy deaths were not in vain.

Lest We Forget 2

If you have loved ones or know of anyone in the storm danger zones, take the time now to locate them, and see to it they are going to survive this with dignity and determination. Let the headlines read when this is over that no baby died from exposure by being stuck in a 14 hour traffic jam. Let's not have someone's grandmother left to out to die on the sidewalk because no one came to her aid before the storm. Let's make sure those without transportation are helped to the pickup stations. This time, let's get it right, not because it will look better for the cameras, because it is human thing.. the American thing to do.

Lest We Forget 3

FRI PM NOTES: You are no doubt aware that Contraflow is a go for all of the New Orleans Metro area starting early Sunday morning, and a mandatory evacuation for everyone south of Interstate 10. If it were my family, I would be leaving SATURDAY MORNING, because you know this scene above will be repeated across many highways. I hope none of you reading this will be stuck in that, because you're on the ball and have a plan in motion. Regarding the storm, I strongly suspect we will see explosive development in the next 24 hours, bringing it rapidly to Category 3. Wilma in October 2005 was in a similar location of the northwest Caribbean and intensified from tropical storm to Category 5 in just over 1 day, so it is possible again. Later in the weekend I will discuss the implications of the slowing forward motion projected for Monday to Wednesday, as I believe this will be the factor to cause as much OR MORE flooding in New Orleans than Katrina. Worse yet, if Gustva reaches Category 5 in the central gulf, and comes ashore as a 3 or above, we may look back on the whole situation and realize that Katrina was a rehearsal.

11 comments:
SOMETHING WICKED THIS WAY COMES

If you live along the I-10 corridor between Pensacola, Florida and Beaumont, Texas, please scroll to bottom of this post for a special list of recommendations I have regarding hurricane preparations for your family. This storm has the potential to be as bad or worse than Katrina, especially for cities such as Lake Charles, Lafayette, Baton Rouge. Towns along the Route 90 corridor could experience a direct hit, from Houma to Morgan City to New Iberia. Please take the necessary precautions now and review the Red Cross Planning Guide as well as my suggestions below.

LOUISIANA RESIDENTS: REVIEW "GET A GAME PLAN" INTERACTIVE SITE FOR HURRICANE PREPARATION, OR DOWNLOAD AND PRINT THE TRAC LA STORM GUIDE. (4.6 MB FILE)

NHC Gustav 6



FRI AM PROGRAMMING NOTE. Now that my 5 year old will be at kindergarten full time each day, I plan to complete and post a daily update either 9:30-10:30 AM or 1:00 and 2:00 PM during major storm periods. This is to clarify posting times for those of you keep checking back for updates, and are disappointed to find none. However, graphics and previous text or links will be tweaked as conditions change. Although I am on a sabbatical from school this year, there is much to do each day watching and teaching nearly-three-year old in addition to keeping the home clutter free of toys and completing coursework for my certificate renewal. I tell you this not because I am self-absorbed, it is so everyone is aware of the factors that will affect the frequency and extent of storm updates. Heck it might even help keep posts shorter!

SNEAK PEEK AT AFTERNOON UPDATE IDEAS: I am conducting an analysis of the factors that will influence Gustav's wind speed, the expected slowdown Monday into Wednesday, and how that could also be affect Hanna's trajectory. I will discuss Hanna's projected path beyond next Tuesday based on upper air factors, and her sustained wind speeds during that time.

EAST COAST RESIDENTS: I strongly suggest filling up your tank early in the weekend, as gas prices will eventually be affected by this storm, since nearly 90% of U.S. Gulf oil production is expected to be shut in by Sunday. Example: In Clearbranch, MS gas at a Kroger store went from 3.19 to 3.51 in less than 24 hours. You know that price action is going to work north.

New Orleans Nightmare


THU PM UPDATE: Three years ago today I was beside myself in bewilderment as to why it took until the morning of August 28 to issue evacuation orders for the City of New Orleans. Finally in the mid-morning hours that Sunday, Mayor Nagin made the announcement. Unfortunately it was beyond too late, and the delay was ultimately a death sentence for many. In 2008 there is hope that the lesson has been learned, for it seems FEMA and Governor Jindal are making it clear they will stay ahead of this storm and a state of emergency was issued early Thursday for Louisiana. It appears that federal and local officials now fully understand that a major evacuation requires at least 60 hours..which is well before even a Hurricane Watch is normally issued (at 36 hours).

NHC Gustav 4

The projected path of Gustav is very different from that of Katrina's and if this comes to pass, puts New Orleans and the southern Louisiana coast at greater risk for long lasting damage. Why? First, the significant loss of wetlands since the storm have reduced this natural buffer even further (a rate of 3 football fields per day). Second, a slow moving strong hurricane approaching from the southeast or south is the worst possible track, for it allows the storm to continuously funnel Gulf water in across Lake Borgne as well as the Breton and Chandeleur sounds into Lake Ponchartrain. Well before any landfall storm surge, this wall of water will overwhelm whatever levee systems are there, repaired or not, just by sheer force of volume. If Gustav slows down by day 5 or 6 as NHC is indicating, this will make the flooding problem just as or more catastrophic as Katrina. The only way to view this storm in a good light is that at least this time, there are less people to evacuate. The image below was taken from a special report on nola.com the week before Katrina, and featured as part of my reporting in August 2005.

No Margin Of Error

For those new to the site since our last major hurricane event, please know there are a few procedures I follow with regard to safety of readers in affected areas. If people reading this site happen to be located in an area of forecasted danger, I normally post recommendations that I would take were it my family facing the situation. However, the responsibility for taking appropriate action lies with the individual, and any harm that might come to someone while following my recommendations is a result of nature driving the environmental conditions. This of course has never happened to me in nearly 5 years of forecasting online, however I make it clear that if someone chooses to act on my ideas, it was a choice of their making, and not something I forced upon them. None of this "But Mr. Foot said I should..."

IMPORTANT STORM PREPARATION IDEAS

IF YOU LIVE ANYWHERE ALONG THE INTERSTATE 10 CORRIDOR BETWEEN PENSACOLA, FL AND BEAUMONT, TX, I offer these ten "Foot Would Follow" Recommendations. This is only a temporary partial list of actions I personally would take if my family were facing this storm. More details will be added Friday and Saturday, for I know many of you will be preparing to head out by then.

1. GET REAL GONE: Making arrangements with family at least 100 miles inland (for peace of mind regarding food, electricity, supplies, availability of cash from your bank, cell phone coverage, etc.). If no family nearby, you better get on the phone and reserve a hotel room or two immediately. Remember the gridlocked traffic? Have 2 evacuation routes mapped out.

2. LEARN FROM THE PAST: Reviewing what happened in recent hurricanes.. what went right and wrong about preparation? What would you do different this time. If you've never been through one, talk to someone rational and realistic in the neighborhood about what they are doing. I've read on forums that Gulf coast residents felt they should have left a day earlier in Rita/Katrina.

3. AM I COVERED: Check homeowner’s insurance, what does the policy say about wind versus water damage? How does it define flooding? Locate all the important family/home documents, take 30 minutes right now and put them in a binder, and put that in a water tight bag. Throw in a couple pencils, sharpies and some notepads. Review the links posted here on An Emergency Plan for Your Family... the Red Cross and FEMA also have good information.

4. STOP THE SALE: Don't be attempting to close on a home right now as insurer’s will not provide a policy within 30 days of an area being declared under a Hurricane Watch. Betcha didn't know that one.

5. BATTEN DOWN: Remove the boats today if feasible and hauling them very far inland. Boaters know how long this takes so it is not a quick and easy job. Leaving your boat at the dock allows it to become a missile into someone else's property or on to a public road hampering relief efforts.

6. DIVIDE AND CONQUER: One of you head to Home Depot today, the other go to the grocery store, right now this exact moment. Non perishables, comfort items, bottled water, canned goods and an opener, soap, insect repellent, first aid kit, batteries batteries batteries. Try an Autoparts store first before the HD. Before you go, Google the phrase: "100 items that disappear in an emergency." I've read that in Lafayette, LA many stores have already run out of supplies, and a similar situation in places even in Jackson, MS.

7. STORM SURGE: If your home is at risk for water or wind damage during landfall… and it’s a Category 3 or above, there’s not much that can be done to protect it. Boarding up windows won't help if the roof is ripped off and the walls collapse inward. Don’t believe me? Look at pictures of Pensacola before and after Ivan in September 2004. What's more important..getting your family to safety or fruitlessly protecting a structure that can be rebuilt?

8. TANK UP OR ELSE: Filling up the car right now this exact moment on the way to Home Depot and before moving the boats. Try to fill up a few of those red lawnmower cans too.

9. WHO'S ON THE TEAM: Making sure everyone in the family is on board and taking the storm seriously. Check on neighbors and elderly or those less mobile. What is the plan to get them out? Who’s in charge of them? Where will they be going? What's the phone number there? Better check on that crazy guy in the neighborhood who says he rode out the Biblical Flood, so he's not leaving this time.

10. TAKE THE INITIATIVE: DON'T WAIT FOR LOCAL OFFICIALS TO CALL AN EVACUATION. If you are of sound mind and body, are a responsible adult with or without a mortgage, with or without children and/or a spouse, and have generally developed a good sense of right and wrong… then by all means.. beat the crowd and evac early to avoid the miles of traffic line that YOU KNOW are coming. Don’t wait for contraflow. Don’t wait to be stuck on a bus that’s stalled in traffic with no air conditioning. It would have taken 72 hours to evacuate pre-Katrina New Orleans, yet the call was not publicly issued until Sunday morning less than 24 hours before landfall. That was way beyond too late.

CONCLUSION: I know some of my reader friends will be saying, "There goes Armaggedon Weather Foot again." I wouls say back to them... "Hey, you have to be right ALL THE TIME.. in a storm like this, I only have to be right ONCE." This time I hope I'm wrong. I’m not advocating that you jump in the car today and split. I’m saying that areas along and south of I-10 are at highest risk for damage and service disruption from this storm. If you want to have a reasonable existence in the post storm period during recovery, make the preparations now.

Let's compare this situation to what would happen if Gustav were heading for the Chesapeake Bay/Baltimore-DC, (as Hannah might do next week!) and I was going to experience 100 mph winds at my house in Dundalk, MD. I would be leaving and fairly soon, probably by Friday. I’d head directly for State College, PA, not up the 95 corridor with my other 9 million metro friends. Sound ridiculous to go 4 hours inland? Not when you consider I have 2 small children, and want to temporarily relocate to an area that is not directly affected, so I can still get groceries and supplies because they haven’t been snapped up already by people living in a “semi-storm” zone that just went a few miles more west to the next store over.

Much remains to discuss, including what Hannah may bring late next week to the Southeast and or Mid Atlantic. Please continue to be patient as the site undergoes revisions. I hear your suggestions to widen the fields, and I am trying to launch a 3 column format, but don't want to inadvertently delete all the features in the sidebar. I hope the biege/green motif is acceptable for now until I find something better.

FRIDAY'S UPDATE WILL FOCUS ON HANNAH, THE FACTORS INFLUENCING HER PATH, AND WHETHER OR NOT THE MID-ATLANTIC NEEDS TO BE CONCERNED ABOUT THIS NEXT STORM.

Wednesday, August 27, 2008

10 comments:
GETTING READY FOR GUSTAV

Gustav in the Gulf 2



WED 8-27 SYNOPSIS: (Supporting links to be added later)
1. Gustav threatens to shut down at least 80% of US Gulf oil and gas production for 5 or more days, depending on the extent of damage and it's eventual path. Energy companies already evacuating personnel from offshore platforms, which are indicated by the white tower symbols on above map. Oil, fuel gas and natural trading are up sharply today in anticipation of supply disruptions before and well after the storm.


2. Galveston, Houston and New Orleans (and their surrounding communities) launching pre-storm preparations, realizing that the hurricane strength could reach Category 3 by early Saturday. Over the weekend, Gustav will traverse a long expansive of the Gulf that has surface temps of nearly 30 C (86 F). This "high ocean heat potential" which will fuel explosive growth, possibly bringing the storm to near Category 5 strength on Sunday.

NHC Gustav 2

TUE 8-26 PM DISCUSSION:

This post marks the beginning of "high season" on my summer forecasting calendar, for the next 3 weeks is considered the climatological peak period of tropical cyclone frequency in the Atlantic basin. Right on schedule, a new hurricane is moving across the Caribbean. In an eerily similar script to Katrina, Rita, Dean and Ivan, early indications are Gustav will easily reach major hurricane status prior to a landfall along the Gulf Coast. If you consider the NHC current projected path (central Gulf by Sunday) and intensity forecast (a strong Category 3 by then) This storm has the makings of a very significant event, as some bloggers I've read have noted even the name "Gustav" seems to sound like it means business. Since the weather is serious business for many of you, improvements to this site continue so that information and posts are real-time or more accessible.

Gustav Tracks 2


Although this site normally focuses on weather risks for the Mid-Atlantic and Northeast, Gustav poses a unique threat to the entire country much the way Katrina and Rita did. The reason centers on likely impacts to the U.S. petroleum industry clustered in along coastal Louisiana and Texas. Ironically as I was preparing this report, The Weather Channel posted a very similar map as featured below. I’m sure you know what’s going to happen if a major hurricane churns right through these platforms, and as expected, the energy industry has already launched storm preparations for next week. Likewise, the State of Louisiana has laid out a comprehensive evacuation and emergency plan. Even the oil futures market stomached a $5 swing over a 24 hour period ending Tuesday evening. Whether you are ready or not, in a week our less this storm will have affected a whole lot more than just the price of gas at your corner station. Recalling my pre-Katrina example, I filled up the gas tank the night before she made landfall, and within 48 hours regular 87 octane in Dundalk, MD had jumped 90 cents. Keep in mind that Katrina pummeled the eastern edge of the platform area, and just 3 weeks later Rita sliced right through it. Gustav's track could affect both sections at once. While I don't want to incite "weather panic", if the projected path into the Gulf becomes more likely, those on a restricted income should consider filling up before the weekend (even here in Maryland). You know full well what the energy market will do, and how it will hit your wallet when it does.


gulf_of_mexico_oil_platorms

Saturday, July 12, 2008

1 comment:
THERE SHE IS, THERE SHE'LL STAY
(for the weekend anyway)

Bertha Visible Satellite 7-11
Today I am starting the trip south from Bar Harbor back to Baltimore, as it will take 2 days. In that span of time, Bertha will have moved very little and probably by Sunday afternoon so I can just leave this satellite image up for most of the weekend, right? For those of you heading to an ocean beach anywhere from Miami to the Gulf of Maine, be alert for swells and rip currents, as many NWS offices have posted advisories to the public on these dangers through Sunday. I very much wish to see by Bertha's departure that no one fell victim to a hurricane 1,000 miles offshore (or anywhere for that matter.) Have a safe and pleasant weekend everyone.

Wednesday, July 9, 2008

No comments:
BERTHA'S OCEAN SWELLS TO BASH BERMUDA
WEEKEND RIP CURRENT DANGER ALONG U.S. EAST COAST

NHC Bertha 6
As of the 5:00 AM July 11 advisory, Bertha has been maintaining maximum wind speeds in the 75-85 mph range, as well as an impressive satellite presentation. According to the Ocean Prediction Center's current Wind & Wave Analysis, and ocean swells of at least 6-9 feet have propagated several hundred miles north and west of the storm. If you are departing on a Bermuda- or Caribbean bound cruise ship this weekend, be prepared for swells near 9 feet in the Western Atlantic. Bermuda's weekend marine forecast is quite rough: offshore swells from 10-15 feet "outside the reef" are expected through Sunday.

Atlantic Wind-Wave 7-9

For East Coasters..if you're just going with family and friends to a small ocean beach, be aware of the increased rip current danger through Sunday as the storm generally stalls east of the Carolinas. Swells of 4-6 feet may be common along many beaches from Florida to the Delaware Bay and 3-5 feet northward to Cape Cod. Despite the hurricane maintaining wind speeds in the center around 75 mph, I noticed the extent of cloud cover expand. Once a decrease in strength is observed, the wind field will expand considerablly, making a larger area of the ocean available for generating waves and swell.


Tuesday, July 8, 2008

6 comments:
HOW BIG WILL BERTHA BE?


World War I era German mortar-howitzer


TUE 7/8 AM UPDATE: The phrase "Big Bertha" actually originates with this World War I era mortar-like howiter manufactured and used by the Germans towards the end of the conflict. As for the size and strength of our hurricane, the maximum sustained winds (shown below) are likely to have peaked, and while those may decrease, the actual size of the storm will increase over the next few days. The wind field of a weakening tropical system will expand over time, but luckily for most of us, this is projected to occur mostly east of Bermuda. Still, the potential remains this weekend for increasing ocean swells along the Eastern seaboard, and beachgoers should stay vigilant about rip currents. Despite the indications that this hurricane may veer east, of much greater impact the weekend of July 12-14 will be cruise ships traveling to and from Bermuda, or from the Northeast or Mid-Atlantic south toward the Caribbean. I'm sure many of you whom have cruised before can tell quite a story about ocean swells and how it made your holiday less than enjoyable, to put it mildly.

NHC Bertha 4

For a birds-eye perspective on what swells can do to an ocean-going vessel, sit down, put all food out of arms reach, don't eat while watching this, and click on this clip I found from Youtube. Although this is a ferry, you can just imagine what the passengers are going through.

If you are unable to view the video, just this one picture says it all about what happens when YOUR DREAM VACATION cruise you've saved up all year for encounters swells. So if you have reservations to cruise this weekend in the Western Atlantic, please don't let me scare you off..just know it might be a bit rough and BRING THE DRAMAMINE! Note: This picture is not photo-shopped.. it is the Voyager in swells of the Mediterranean.

The cruise ship Voyager negotiating swells in the Meditteranean

CATEGORY 3 BERTHA...BEARS WATCHING

Bears Watching 2

As of the 5:00 PM Monday 7/7 advisory, Hurricane Bertha has strengthened to Category 3 on the Saffir-Simpson scale, with maximum sustained winds of 115 mph. Perhaps this is as much of a surprise to you and me as it is to the forecasters, for no one truly anticipated such a rapid intensification over marginal sea surface temperatures. More details on the explanation behind this surge in strength can be found in the current NHC discussion. Although I disagree with their last sentence, for Bermuda and the entire Eastern coastline will begin experiencing ocean swells toward the end of the week. At the very least, Bermuda will have heavy surf and if Bertha stalls in the west central Atlantic as projected, several days of increased swells along the East Coast will pose a significant hazard to swimmers, sailors, boaters, fishermen and many other coastal interests. If you have plans this coming weekend that will take you anywhere into the Atlantic Ocean, I urge you to be highly cautious of rip currents especially with regard to children and non-swimmers. Just because a hurricane is stalled offshore does not mean you are safe from it's effects.

Bertha the Buzzsaw

MONDAY 7-7 AM UPDATE: Sorry, I just couldn't resist that one, (Bears Watching) for it's been 3 years since this particular headline was last used. As you probably already know, Bertha is the first hurricane of the 2008 Atlantic Tropical Cyclone season. What you may not know is exactly 12 years ago to the day...July 7, 1996, we also had a Hurricane Bertha in the Atlantic. Another interesting twist is that this storm has given a restaurant in Fell's Point Baltimore a unique if temporary notoriety. As reported by the Sun newspaper, Bertha's is offering discount hurricane drinks, the portion size of which may increase as the storm strengthens. Those who frequent Fell's Point know it is the place to eat Mussels, and now perhaps a new tradition will be born in Charm City... thanks to the tropics.

NHC Bertha 3

You'll notice a sharp decrease in the distance Bertha is projected to travel from Friday to Saturday. Influence from the subtropical (Bermuda High) is likely to play a major role in where the hurricane ends up making her final run, as well as interaction with a frontal boundary moving east from the Great Lakes in the middle and latter part of this week. I am beginning to woder if the weekend track of this storm will resemble that of Hurricane Jeanne in 2004, which meandered off the Florida coast for nearly a week before making landfall. I'm sure our instructor, Lou McNally of the Weather and Climate Class will be continuing to make this a teachable moment for my colleagues and I. As we get to apply new forecasting skills from class, I'll be updating further on what I think are Bertha's plans for the weekend.

Saturday, July 5, 2008

6 comments:
DOUBLE TROUBLE AHEAD:
1. CAPE VERDE TROPICAL STORM...RECURVING?
2. INSTABILITY IN THE WESTERN GULF

Atlantic Basin 7-4

SAT 7-5 AM UPDATE: The Tropical Atlantic is starting to produce noticeable activity, view the latest infrared satellite loop. As of 11AM Thursday morning, the robust tropical wave off the West African coast was upgraded to Tropical Storm Bertha, and may approach hurricane strength late in the weekend.

SYNOPSIS: Bertha is the first named tropical storm known to have developed this far East in the Atlantic. At present, upper level air flow patterns indicate that a landfall on the U.S. mainland cannot be ruled out. In the southeast Caribbean, a weak area of low pressure had been producing scattered showers and thunderstorms, but remains disorganized. However, activity continues to flare up west of the estimated center as the overall system drifts west-northwestward. A broad area of showers and thunderstorms is also present near the coastal Texas/Mexico border and will be monitored this weekend.

Bertha 3

FIRST, THE CAPE VERDE SYSTEM: View this enhanced infrared loop. Ironically the last notable tropical cyclone to form in this region at this time of the year was...Bertha, in July 1996. With a classic summertime Bermuda High ridge forecast to start building next week, one might initially think the storm could travel under the ridge and in the general direction of the Caribbean. When considering the air flow at upper levels, a different trend is revealed, and you would see why some computer models are indicating recurvature east of Bermuda. A brief explanation for this is provided in the "upper level analysis" section. Below is the current NHC projected path from 5PM 7-4, and preceding it is the 11AM Advisory.

Bertha 2

Notice the westward shift in the cone of uncertainty from one map to the next.

NHC Bertha 2

UPPER LEVEL ANALYSIS: This next map is among the many new features I've been learning about in my Weather Forecasting and Climate Change class here at the picturesque College of the Atlantic. As I experiment with a new feature or skill from the class, it will be added here for use during this year's hurricane season. The newest (to me) resource is the 500 mb 24-hour forecast for the Central and North Atlantic issued by the Ocean Prediction Center. The inference I am making from this map is that once Bertha nears the Low and High progged at the 500 mb (~18,000 foot) level, the air movement between these two centers will create convergent flow south to the south side, with air diverging on the north side. This will act to pull the system toward the vacuum created by this flow, and begin curving the storm northwest and eventually northward into the central Atlantic. The NHC refers to this as a weakness in the subtropical ridge. This is an example of the importance of knowing movement of air masses and pressure differences at upper levels, which ultimately dictate what is observed on the surface for us ground observers.

Atlantic 500MB 7-3-08

BACKGROUND: A tropical wave developing off the West African coast is referred to as a "Cape Verde" system due to the promixity of an island cluster of the same name. Were this occuring between mid August and late September, we would have great cause for concern. This early in July, waves way out there usually don't become the Katrinas, Ivans, Floyds or Glorias and come terrorizing the Gulf or East Coast. Each tropical season, one hundred or more disturbances drfit off the African coast and cross the Atlantic. In July 2005, two of these systems reorganized once near the Caribbean and developed into named storms. Dennis made landfall as a Category 3 Major Hurricane on the Florida panhandle July 10 of that year. Just eight days later, Emily has already crossed the same southern Caribbean waters, and struck the Yucatan on July 18 as a Category 4. Emily also had a second landfall south of Brownsville in Northeast Mexico as a Category 3. I realized in reviewing the archives on both storms...back on July 6, 2005 the Atlantic basin had nearly an identical setup: A tropical wave just off the African coast (which would become major Hurricane Emily), AND a small feature in the southern Caribbean which became Dennis.

SECOND: THE SOUTHERN CARIBBEAN SYSTEM. View the latest satellite loop. While the system is being sheared by upper level winds, it is also about to enter surface waters nearly 2 deg F above normal, and low level steering currents favor a west-northwest path for the next day or so. Despite the shearing, thunderstorms continue to flare up west of the center. Closer examination of the environment ahead of this wave is warranted over the weekend. Any system named in that region of the Atlantic Basin this time of year will be a cause for concern among emergency management officials, cruise operators and the especially oil market. In fact, I suspect that many astute futures traders are watching this area closely For an even more serendipituous perspective on the economics of hurricanes, consider investing in the Hurricane Futures Market, as first reported by MSNBC in 2005. As Dave Barry would say, "I am not making this up."

Invest 93L Satellite 7-2

While this system has decated, compare the earlier projected path to the NHC official tracks for Hurricane Dennis in July 2005, as recorded in this link to the archives for that period.

Invest 93L Preliminary Model Tracks

Under the training from our Weather and Climate Instructor, I've gained a new appreciation for the importance of applying real time interpretation skills to existing atmospheric data. I've spent the learning from Dr. Lou McNally, who with 30 years service across in both the private and public forecasting industry, is a super-rich source of knowledge and we are very fortunate to have him take time out of his crushing schedule to shepherd us through the nuances of weather analysis. Thanks Lou, for making this a highly informative, useful and thought-provoking class thus far! For me it is uniquely fun and beneficial, as I have been implementing the skills learned in class almost immediately, and hopefully those of you following this site will see the payoff in a better understanding of what drives the weather.


PREVIOUS UPDATE- WED 7/2 4:30 PM. From beautiful Bar Harbor in Downeast Maine, I wish you all a safe and weather-friendly Fourth of July Weekend. I shall have the day off from my Weather Forecasting and Climate Change course here at College of the Atlantic. If our class forecast for the weekend holds true, then I plan to revisit Acadia National Park via the island bus service and take my rented mountain bike with me. During lunch each day, I take a short bike into the wonderfully quaint town that is Bar Harbor (yes I will post pictures soon). On Tuesday 7/1 my classmates and I journeyed atop Cadillac Mountain for incredible views of the Maine coastline as well as cloud and front analysis. At 1,530 feet, this mountain is the highest point directly on the Atlantic coast north of Brazil, and it is quite a sight to look out into the ocean from it's summit. Thank you to the well-wishes of those whom have made Bar Harbor among their vacation spots, and I can now see why you think so fondly of this place. As I pedal through the rustic and unique downtown, I think fondly of all you as well and wish you along with my family could be here to enjoy the sights, fresh Atlantic air, and great people that comprise the wonderful region known as "Downeast Maine."

Friday, July 4, 2008

3 comments:
THE BEAUTY THAT IS DOWNEAST MAINE
FRIDAY 7-4 UPDATE: CHECK THIS SECTION FOR NEW PICS IN THE WEEK AHEAD

Forecaster Foot finally makes it to Downeast Maine
One of many rugged inlets found along the coastal section of Acadia's Park Loop Road.


A view familiar to many of you: The islands of Frenchman Bay from atop Cadillac Mountain

I cannot recall the name of the islands shown... something about the "Sleeping Lambs?"
Those of old timers with more background on the Barbor will know in an instant I'm sure.


College of Atlantic's "Seaside Garden"
Where I'll be posing for the cover shot of next month's issue of Cottage Living... a beautifully serene place in front of the College's Administration building, known as the Seaside Gardens.
College of the Atlantic, Bar Harbor, ME

Starting Sunday, June 29 I will be spending two weeks at Maine's College of the Atlantic in Bar Harbor (or as I have learned, is pronounced 'Bah Hahbah'). What am I doing in Maine you ask? I am enrolled in a 4-credit graduate course to enhance my background and understanding of weather forecasting and climate change! Sadly I have to celebrate my 12 year anniversary away from my lovely wife and little Foot girls, but to reassure all the Moms and wives out there, I did leave Mrs. Foot a very nice card with special hand written messages inside. Originally the ladies were going to accompany me on this journey, but a number of complicating factors...including the price of fuel, scuttled those plans. But we may try again next year so we can all attend the Family Nature Camps.


The other real reason I'm here is that this course is part of a year-long process to complete the outstanding credits required to maintain my Maryland teaching certificate. So it may come as a shock to you (although my students already know) that I am taking a one year leave of absence from teaching to finish the credits and lock that Master's Equivalency under my belt.


An All-Forecaster-Bulletin: Mr. E.H. of Woburn, if you're out there and not already on vacation, please contact me via the comments as soon as you can. I would have contacted you by email, but lost the address when my previous computer checked out. I'll be in the Boston area Sat/Sun July 12 and 13 and it would be a real honor to finally meet you, have lunch and revel in the wonderful New England scenery and summer weather. I'll be sure to post some pics of the experience in Bar Harbor as well as new insight gained on upcoming trends for the hurricane and winter storm seasons.
CollegeoftheAtlantic

Saturday, June 28, 2008

10 comments:
"IT HAPPENED BEFORE...IT WILL HAPPEN AGAIN.
It's just a question of W H E N."
- voice of Charleton Heston, in the opening scene from Armaggedon.
1. EXCESSIVE HEAT DISMISSALS. June 28 followup comment: The call made on June 5 played out in Baltimore County Schools as expected, with a 3 hour early dismissal due to heat on Monday June 9. am wagering that many county school systems in central Maryland and Northern Virginia will be forced to close 2 - 3 hours early this coming Monday. It's actually not about the daytime high..but rather the overnight low. If you arrive to school at 7AM Monday with a morning temperature already at 80 F in 90% humidity, it will not take long for regular daytime heating to boost that up to 90 before lunchtime.


2. ISABEL WAS ONLY A REHEARSAL. The current weather pattern I believe is a continuation of what I explained to many people at my school and elsewhere. The Mid Atlantic would experience a fairly cool and drawn out spring, with temperatures staying at or below normal. Then come early June, we would race into the 90's and stay above normal into July. The traditionally hottest periods of the year..late July into early August, may in fact be cooler than normal, and that I am concerned might setup a persistent upper level trough along the East Coast. With La Nina now backing off and the possibility of even switching over to a weak El Nino, this whole scheme is looking eerily similar to the summer of 2003. Were the Bermuda High to back off into the Atlantic come September, and a weak trough establish near the coast, this has the potential to steer any western Atlantic tropical systems toward the Eastern seaboard. Since 2003, I have been telling hurricane watchers and many others that Isabel was truly just a rehearsal, and the bigger threat is a 1933 type Category 2-3 storm that travels up the west side of the Chesapeake Bay. You know what Mr. Heston said, right...


3. SUNSPOTS, PACIFIC WATERS AND POLAR SEA ICE. These are three major influences on Eastern US winter weather that will be receiving top-billing on this site over the next 6 months. Were you to combine the upcoming sunspot cycle minimum (decreased solar output this winter) with a switch over from a currently fading La Nina to a possible weak El Nino, and a rapid return of Northern Hemisphere snowcover and polar sea ice...what do you have? I believe these three factors point to a less-than-active hurricane season followed by above normal snowfall for the Northeast and Mid-Alantic. My overall projection for this region is that this coming winter will more than make up for the lackluster performance of the previous two and closely resemble 2002-03. You all no doubt remember that season featured the February President's Day Blizzard (remembered now as "PD II" ) among many other heavy snowfalls in the I-95 corridor. I remember it well for the 9 snow days in the Baltimore County Schools.

Tuesday, March 11, 2008

14 comments:
FEEL FREE TO TALK AMONGST YOURSELVES

We will soon be entering the long quiet period when powderhounds go into sad hibernation until the promise of major snow looms again come next winter. While close monitoring of any potential storm surprises will continue for another few weeks, it is obvious to all that opportunities for significant snow in the southern I-95 corridor are just about over. There have been a few exceptions, notably March 1956, 58 and 60. The now finally negative NAO signal may lead some to believe that a coastal storm could pack a last minute wallop, but the strong March sun offsets this possibility in most cases. As we go forward into April, discussion and focus of this site turns first to nailing down the date of the last frost in the Mid-Atlantic. Beyond that, we begin turning our attention toward what the hurricane season may bring. You are welcome to continue posting on snow possibilities as they may yet occur before we close out the month. Thank you to all for your patience and participation in a short but interesting winter storm season. I hope you will return again for more lively discussion next season!

Tuesday, February 26, 2008

49 comments:
A TRIP TO FANTASYLAND..FOR THOSE GOING SKIING
(IT WILL BE POURING SNOW AT MY 7 SPRINGS SKI TRIP THIS WEEKEND, AND EVEN BETTER...THE FOOT GIRLS WILL BE THERE TO ENJOY IT ALL WITH ME. )
Fantasyland


(No, not that one. I'm talking about the GFS Fantasyland...this one:


GFS FantasyLand


TUE 2-26 10:30 PM. I know it's hard for you ravenous powderhounds not to get excited when you see maps like this. It's similar to how the administration gets teachers to attend faculty meetings on time, they just announce that chocolate is being served to the first 25 people who show up. You've never seen teachers move so fast after a long school day. If they consider chocolate a food group, then people like you reading this site probably consider impossibly fun computer model scenarios sweeter than pure sugar itself. Just a minute, I need to grab my evening dose.


Ok, back now. ::head twitching:: I call this the GFS FantasyLand, because it is just one model run of the US based Global Forecast System from Monday 2/25 showing some crazy scenarios for next week's storms. One idea going forward from here is that it appears increasingly likely something very significant will pound the East Coast the middle of next week. While climate indicators don't seem that promising: The NAO is strongly positive, the PNA fading to near-neutral. This is opposite of the setup we prefer: a negative NAO (trough in the East), a positive PNA (ridge in the West). Regardless, the GFS, European, Canadian, et all are all showing a major major event swinging east by next Tuesday morning that is going to be hard to avoid. Although a lot can and will change over the next 7 days leading up to arrival of this event, it is interesting to note a number of models have continued to show something brewing for the 3/4-5 period now for several days in a row, so we will keep watching.


Yes, I know, the same thing happened in March 2001... for days before, the models projected a massive Day After Tomorrow type blizzard which was going to bury the 95 corridor under 2-3 feet of snow. The hype was galactic in nature, and schools were closed all the way to the Moon. Everything was shut down from Boston to DC, even BEFORE the storm struck. It was my first year of live classroom teaching in science, and I was in Lancaster County, PA at the time. I remember just before going to bed that night, a TV forecaster from Philadelphia showed the entire viewing area under a deep blue shading with 24" - 36" plastered over it. The next morning, I awoke to 2 inches. The storm had shifted east overnight, blasting northern and central New Jersey as well as parts of New England with just some of the crippling snow that had been expected in the cities. It was and still is in the minds of many weatherfolk, the biggest bust in the history of Mid-Atlantic weather forecasting.

Monday, February 25, 2008

9 comments:
WILL SCHOOLS FINALLY GET A FULL WEEK?

TUE 2-26 10:00 PM. At least your week in the Mid-Atlantic started tranquil, with sunshine and seasonable temperatures on Monday. From here it gets interesting, and much colder. On Tuesday, the vigorous cross-country system that impacted western states Sunday arrives on the East Coast with force. By afternoon, heavy windswept rain overspreads the region, with temperatures rising into the 50's on southeast winds. Overnight into Wednesday, a powerful cold front sweeps to the coast and leftover moisture may briefly change to snow before ending. Noticeable sub-freezing temperatures will arrive behind the front, creating pockets of black ice that could cause some school delays Wednesday morning in Baltimore County's Hereford Zone along with some parts of Frederick, Carroll and Harford Counties. Starting Wednesday, the region spends remainder of the week in January-like conditions, with highs in the mid 30's to near 40. The next chance for precipitation looks to be a clipper on Saturday bringing flurries or light snow.


Later this evening, I will post some basic ideas about next week, as it appears there's one or two more chances for snow during the upcoming 10 day period. I did leave some snippets about it in the previous post if you want to go look for them!

Sunday, February 24, 2008

23 comments:
A KA'NO'NA FOR THE 95 CORRIDOR

It is very unlikely this system will trend far enough south to become a major coastal Kahuna/snowstorm. The surface Low will remain over land and not transfer energy or redevelop off the Carolinas. Regardless of that, this system will have tremendous energy and impact the northern half the country from California to the Northern Plains, Great Lakes and into New England...bringing heavy snow and significant icing across many states. This Accuweather graphic breaks down the storm evolution well. A current satellite image from the west coast shows quite a bundle of energy now moving through the Rockies.

February Finale 1

SAT 2-23 7:00 PM. FEBRUARY FINALE IDEAS: The newest Euro and GFS (not shown here) is keeping the primary surface Low near West Virginia/PA Tuesday night. This is being closely followed by HPC as you would expect. You can follow the model animation here. Note that I don't hug just one exact model, I'm providing this as representative of the trend that's developed with our next storm between the GFS and Euro. Also of note are the trends with the NAO (risen to strongly positive) and PNA (still strongly positive but dropping sharply). Those indicate a more zonal or east west flow across the country, further limiting any chances for a big coastal storm. However, you will feel a SuperKahuna blast of cold air, and may set the stage for a Winter Finale as we head into the first week of March. For the sake of ravenous powderhounds, good ole' Mr. Margusity of Accuweather is keeping a distant eye on upcoming storms. You can also peruse the Eastern US Weather Forums on what others are saying about indicators of these storms or lack thereof. If you really want to take a trip down Weather Fantasyland lane, another blogger like me has..believe it or not..created an entire site just for the purpose of tracking ONE storm. Hey now, don't knock it, because regardless of the outcome, it's fun for us crazy powderhounds simply to have a potential storm to track over a 10 day period. The site title is "Storm of the Century" and the link is: http://youhavebeenwarnedmarch5th.blogspot.com/ (note: do not click on link if you're from BCPS, it will be blocked due to the domain name.) Laugh now, while you still can.

February Finale 2

SAT 2-23 8:00 AM. POST-STORM SYNOPSIS: The Mid-Atlantic and Northeast did experience a prolonged period of wintry/frozen precipitation as originally anticipated, but it ended up being much more intermittent than forecast, which reduced storm totals. Despite lower accumulations, what did fall was more than enough to make travel extremely hazardous for many areas during a majority of the storm period, so this time it seems the region-wide closings were better aligned toward safety than over-reaction.


Before we launch into another 5 day period of storm analysis, there needs to be a debriefing on what was originally said about the current event compared to what happened. Some of the ideas I've thought of initially are this: I believe the storm's underperformance was due in part to temperatures Thursday night 2/21 not decreasing as much as originally anticipated. Had it been 26 in Baltimore as forecasted for example instead of 29-30, I ascertain the changeover from light snow to sleet/freezing would not have occured as quickly from the city south and east, robbing snow potential. Instead, evaporative cooling from snow falling through those lower temperatures might have kept the temp down in the 20's all day, enhancing the freezing rain potential once it did arrive. Granted there are lots of other factors, but one cannot ignore the effect a 3-4 degree difference in temp would do at the onset of a storm.


The GFS and NAM computer models overall handled the precip onset well, and 48 hours out had finally settled on a reasonable solution, but appeared to have overdone the amount of liquid available. In addition, it was clear to all of us watching the radar that the two systems were not going to phase together. Knowing this, we should have better anticipated the dry slot was going to monkey wrench the forecast...as in robbing some areas of precip (say from Anne Arundel-Howard Counties west to Frederick County). The NWS did actually factor this into their forecasting, but the results made it appear the whole situation caught them by surprise, which in fact they knew and saw it with their own eyes. The Sterling VA NWS office only recorded a trace of snow, when the expectation was for 1-2 inches overnight. The same story was repeated in many of your backyards, and it appears no one in the "comments community" observed an accumulation greater than 1.5" right?


I welcome any of your post-storm analyses, (the what happened and why) and will be glad to post them here in the main site with you as the author. Our first responder is Kyle from Howard County, and his writeup appears below the storm grading section.

POST-STORM ACCURACY CHECK: A general lookback at (1) The original forecast (first issued publicly Sat 2/16) and; (2) The final call (posted below). Where was the call right on, where did it bust, and why?

FINAL ACCUMULATION SUMMARY: Time frame for these total storm projections is the originally forecasted period of Wednesday 12PM 2/20 to Friday 12 AM 2/22.

MAXIMUM PRECIP AMOUNTS: FORECAST 3" along the I-95 corridor from Washington to Philadelphia. 4" in central and southern Maryland, 5" in northern Virginia, western Maryland, the WV panhandle and southeastern PA. My location of Dundalk and the nearest official reporting station, BWI, will be used to grade the prediction. I project BWI will have a total of 3" of snow/frozen precip, and Dundalk, MD will max at 4". These numbers included ice. ACTUAL: Because the original call was for totals to include Wed PM to Fri PM, that includes the clipper snow Wed afternoon. Results are listed as: -Location: Forecast / Clipper amount + 2/22 amount = total / forecast = Departure in % and Final Grade. Source was NWS Public Information Statements from my link pages.

THE "BUST-APOLIS" INCLUDED:
-Dundalk (Central MD): 4 / 1.80 + .30 = 2.1 / 4 = 50 % E
-BWI Airport: 3 / 1.0 + .20 = 1.2 / 3 = 40% E
-DCA Reagan National Airport: 3 / Incomplete no data, assuming it was E
-Fairfax, Northern Virginia: 5 / 1.25 + .1 = 1.35 / 5 = 27% E
-Martinsburg, WV (Panhandle): 5 / 1.5 + .20 = 1.70 / 5 = 34% E


THE "BLUE-RIBBONS" WERE:
-Garrett County (Western MD): 5 / 3 + 2.5 = 5.5 / 5 = 90% A
-PHL Philadelphia Airport: 3 / .2 + 3.2 = 3.5 / 3 = 86 % B (over by 14%)
-Paoli (Southeastern PA): 5 / .5 + 3.5 = 4 / 5 = 80% B

POST-STORM SUMMARIES SUBMITTED BY READERS: First up. Kyle from Howard County, MD. You are welcome to submit yours via the comments and I can post them here.
1)The NAO did not trend negative, rather trended positive while the PNA Index also stayed on the positive side. We wanted a negative/positive setup.
2) A strong La Nina hasn't helped us this whole winter, however I was thinking that it actually would on this storm because of the warmer than normal gulf, but alas it didn't.
3) The jet stream seemed to be too fast and too strong, thus carrying the storm quicker than predicted, perhaps robbing some moisture gathering time.
4) Longer than desired southerly winds eating at that cold air dome.
5) Those darn mountains and mean bay: Seems like storm after storm looks good on the radar over Ohio/Tennessee until they reach the Appalachian Mts. where any storm seems to come out deformed and weaker. The bay, as Mr. Foot has mentioned, keeps on radiating heat throughout the winter, which surely didn't help our pre-storm temps.

Friday, February 22, 2008

71 comments:
SATURDAY = SLOW WARMING, MUCH MELTING

FRI 2-22 4:00 PM. The latest Baltimore NWS forecast indicates that while the storm is not over, we are on the upside and bulk of precip has passed. Intermittent freezing rain and drizzle along with areas of fog throughout the DC and Baltimore regions may hamper the evening commute. As Capital Weather pointed out, when the sun dips, some wet less traveled areas will likely refreeze somewhat. I also am pleased to bring you a new feature and interactive feature discovered on their site. You can active it simply by clicking and scrolling.


MAXIMUM ICE AMOUNTS: (FRI PM: Obviously this entire section of the forecast busted, no one saw ice amounts exceeding 1/4" in the entire region, according to storm reports.) My projection of icing inside the numbers posted above. From Washington to Baltimore: .50" of freezing rain / .75" of sleet (includes the adjacent Metro Counties) Areas farther north and west (from Carroll County on west and north: .25" of freezing rain / .50" of sleet. From Harford County north and east to Philadelphia and it's western suburbs: .75" of freezing rain / 1" of sleet.


MAIN IMPACTS: Snow changing to sleet and then freezing rain by noon south of the PA-MD line, and over to freezing rain by nightfall north of the PA-MD line. (FRI PM: That part did generally occur, although much earlier than expected, by mid morning in many locations) Once accumulating snowfall has ended and freezing rain trends become clear, NWS will likely switch Winter Storm Warnings over to Ice Storm Warnings for much of the region. This may very well lead to one of the most paralyzing ice events of recent years for the I-95 corridor, and could surpass the Valentine's Week Disaster of 2007 at least in terms of total ice accretion. (FRI PM: Since 1/4 - 1/2 inch of ice did not materialize, neither did these predictions verify)

FRI 2-22 10:00 AM. For those of you new to the site, we have a special term in the Baltimore region which is reserved just for events like this...CLEAN SWEEP! That means all metro area county schools are closed, along with the vast majority of the private schools, and reduced schedules/liberal leave at county and state government offices in addition to many community colleges deciding to close. I learned late this morning that even brave and strong Garrett County closed, and there were delays across the Lower Eastern Shore. A similar story is being repeated from Kentucky to West Virginia, through Central and Southeastern PA and into New York/New England. In fact, every school district I've ever lived or worked in (6 of them.. PA/MD) is closed today. Unfortunately, it is not a total sweep as it appears some district offices remained open, especially Baltimore County. So a special "wish-it-could-have-been-a-Happier-Friday-for-you" message goes out to all the office workers who now have to take a vacation day if they want to stay home. There's also many commuters whom still have to brave the elements today, and I'm sure you can tell by looking out the window they are brave people indeed. Here's hoping you all can at least try to leave early, and that you make it home safe without having squeezed your knuckles off while driving.



inmaSIRNE



There now, doesn't all that make you feel warm and cozy inside? Please continue to post your location and observations in the comments, especially your temp and total snow/ice thus far. I will leave all the previous posts on this storm below so you can reminisce and look back at the evolution of the forecast. When time and children needs permit, I will post a brief overview of ideas going forward into next week regarding the potential SuperKahuna. Happy Friday Everyone!

Thursday, February 21, 2008

86 comments:
THE PROOF HAS ARRIVED, AND A LITTLE EARLY.
CHECK THE LATEST MID-ATLANTIC RADAR FOR PRECIP TRENDS

inmaSIRVA_

THU 9:30 PM. The Winter Storm Warning now in effect until 10 PM FRIDAY for Central and Western Maryland, Northern Virginia and the West Virginia panhandle probably comes as no surprise to those of you who have been following the development of this storm since last Friday. There are no changes to the forecast, because the truth has arrived : A high impact winter storm will affect the entire Northeast region Friday into Saturday, and not a soul on Earth can stop it. View the NWS spread of warnings and advisories to understand the extent of this storm already. As for the current radar, I'm sure you're noticing the "dry slot" of separation between the two storms, but that is simply an indication the two storms will not "phase" or merge together quickly. This allows the energy from both systems to slowly blend, which actually prolonges the event...and the pain for commuters. The alternative is a rapid phasing, a quick accumulation and then out to sea. That is not likely to happen.

STORM SUMMARY AND IMPACTS: An initial 1-3" of snow starting by midnight in the central Mid-Atlantic will be followed by nearly 24 hours of sleet and freezing rain to affect the entire I-95 corridor from Washington to New York City. Interior sections from Pennsylvania to England will see widespread snow possibly exceeding 6 inches. By Friday afternoon, areas affected by ice may come to a virtual standstill, even hampering the ability of emergency and utility workers to reach residents in need. If you have something important to do, get it done on Thursday, because travel on Friday for most of you will be limited to your living room, TV room and the nearest refrigerator (assuming there's power to keep it working!)

SCHOOLS, COLLEGES, OFFICES: Most schools throughout central and western Maryland, northern Virginia, West Virgina will be closed Friday, in addition to a number of colleges as well as many county, state and federal offices. Any activities, meetings or special events planned for Saturday will have to be rescheduled, so make necessary arrangements now. Those who attempt to open or hold an event will face a travel and logistical nightmare. However, conditions will improve behind the storm on Sunday, allowing roads to dry out in time for a regular school day on Monday.

BACKGROUND AND ANALYSIS: (Skip this part if you're not into the meteorology behind the forecast). The green-blue areas on the map below indicate moisture that will by 1AM Friday be running overtop an expansive dome of sub-freezing surface/lower level temperatures. The lines that bend southwest across Virginia indicate cold air damming, a classic setup for sleet and freezing rain, which may initially start as snow. Also note the 0 deg Celsius line at 5,000 feet is deep in southern Virginia, that indicates an extensive southward push of cold air. Warm air advection at or above the 5,000 foot level will intrude later Friday morning, this will be evidenced by snow changing to sleet and then eventually freezing rain by noon. This is well depicted in the NWS forecast for Baltimore as a representative location for the central Mid-Atlantic. Comparing this Wednesday night GFS projection for 1AM Friday to the current radar, it appears the precip is moving in faster than expected, but may result in just slightly higher snow totals if it starts earlier, despite your concern about the "dry slot."

GFS 1AM Fri 2-22

THE MYSTERY OF FREEZING RAIN. Surface temperatures on Friday will start out in the 20's, and then you'll see a quick rise to 30-32 in many areas, followed by a whole day where the temp hovers just around freezing. This is a phenomenon that often occurs with freezing rain, because water turning into ice is actually a CONDENSATION process, which RELEASES heat into the atmosphere. This "latent release of heat" helps keep the temperature just around 32 or 33. But strangely enough, if slight melting begins to occur, EVAPORATION of that water from a solid back to liquid is a COOLING process, which in turn chills the surface layer just enough to stabilize the temperature. So in effect, once a freezing rain regime has setup, it just keeps on going until enough warm air aloft mixes down to the surface and provides enough warming to take the air temperature past 33. Given the depth and coverage of the cold High pressure dome that's now in charge, I doubt we'll see a change to all rain by Friday afternoon as projected by Baltimore's WJZ. It will be fun to see who is right in the end.

IF YOU WANT TO NOWCAST THE STORM, you don't have to wait for me...I recommend monitoring the following sites over the next 48 hours. For up-to-the-minute data on road conditions in MD, check Maryland Roadway Weather, and if you want the latest indications of precipitation type at BWI, this helpful graph from coolwx.com breaks down what may be falling when. A good sense of what's happening with precipitation and storm movement is best seen on AccuWeather's National Radar Loop and Regional Snow-Ice-Rain Radar, and this map of current observations. If you want more detail and like to decode secret messages written in acronyms, then follow the Baltimore/DC NWS Forecast Discussions, updated about 4-6 times per day. Those who seek serious hard core meteorological prognostication should review the HPC Short Range Discussions. (That's short for Hydrometeorological Prediction Center.) For weather analysis and long range entertainment, Henry Margusity's "Meteo Madness" provides a blend of both.

Justin Berk is a TV meteorologist with ABC2 News in Baltimore who operates a very worthy blog I suggest bookmarking, and since I've been a life-long fan of ABC, I can't recommend any other network anyway. For a long range glimpse of what US computer models are projecting for next week, take a peek at the GFS animation on wunderground.com. There's also the NOAA/NWS 5-day map series, and you can even see our future SuperKahuna indicated there starting Wednesday 2-27. Once we get the first Kahuna launched in full (translate: me home Friday for a day off to do the analysis), then I can start to show you data and maps for next weeks potentially major event that could make this upcoming storm look like a flurry!