Saturday, July 12, 2008

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

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

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

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

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