Friday, December 16, 2005

AN EARLY CHRISTMAS PRESENT:
A NORMAL WEEK AHEAD


THE QUICK FORECAST..
1. No big storms next week, just cold weather
2. Xmas week...mix of cold/warm, some rain/snow
3. January disappoints with above-normal temps

Xmas Week 05



Dec 4A

For those of you who did not get the delay or closing you hoped, at least it is a "payday Friday" for many of us. Considering that the holiday vacation time is fast approaching, it is comforting to know that the Northeast will have a quiet week coming up. With people making travel and shopping plans, kids off the wall, parents getting frazzled, teachers ready for a break...at least the weather will not throw a monkey wrench in the calendar between now and next Friday. The GFS (Global Forecast System) map shown above is usually the forecast model of choice for the NWS, and the next storm progged for Sunday afternoon looks to skirt along the southern Mid-Atlantic. Following that, a period of below normal temperatures will set in for remainder of next week leading up to Christmas.

SO WHAT HAPPENED TO THE STORM?

Dec 3E

Blame the big time changeover to rain on simple physics. Counter-clockwise air rotating around the Low pressure center as it moved north along the I-95 corridor pulled in much warmer, moist air from the Atlantic. In fact, water temperatures along the NJ coast, Long Island and New England are above normal, while coastal areas along the DelMarVa and the Carolinas are below normal. This may be a factor behind the sharp temperature contrast shown above as the storm pulled north...southern and central Jersey had a nearly a 30 degree rise in temperature over 24 hours! I did not forecast for the I-95 cities in this storm because it looked clear from the beginning they would get more rain than snow. Philadelphia was the exception as they received snow where rain was expected first. My call for schools was off somewhat or at least reversed as I expected some closings and instead we had early dismissals. The graphic below from Accuweather.com illustrates the second phase of our storm as it heads north, giving Boston a taste of Baltimore weather... snow, then a period sleet and freezing rain, then rain.

Dec 3F

Thursday, December 15, 2005

WHAT'S THE FINAL WORD FOR FRIDAY ?
(THIS POST FOR DC-BALTIMORE-PHILLY-CENTRAL/EASTERN PA)

Dec 3E Radar

As of 4:00 PM, our storm is well underway and has wreaked havoc with everyone's Thursday program, however it was very helpful that schools gave parents a lot of advance notice to make arrangements for the EXTREMELY early closings (2 and 3 hour closings were widespread in central Maryland). It appears that the snow, started earlier than expected, and hung on longer. At present, the colorized radars are showing conflicting precip types, and in comparing the radars between Accuweather and Intellicast over previous storms, I tend to side with Intellicast as it more accurately depicts what is taking place in my backyard. At present I have moderate freezing rain and this has been going on for several hours now.

SCHOOL CLOSING SUMMARY

Yes, I know... the real reason you are here is to decide if you have to do lesson plans or homework for Friday. Well, just plan ahead, wear your pajamas backwards and put the snow shovel upside down and that'll jink the storm so you can sleep in tomorrow, right?

DC schools: Probably opening on time, changeover and melting will allow roads to improve over the next 12 hours. N. Virginia: At least a 2-hour delay if not closed due to a longer period of freezing rain.

Baltimore City and south: Delays likely, closings unlikely due to earlier changeover to rain. (I expect Anne Arundel to have perhaps a 1-hour delay but not closed, as they would have switched over to rain early tonight.)

Baltimore/Harford/Cecil Counties: Tough call here. I am going out on a limb and saying they are going to start with a 2-hour delay and then see how much melting/warming takes place. Obviously if we wake up and discover the temps rose to 40 overnight, then it's a no brainer, you'll be in on time Friday. The determining factor is to what extent the northern and western parts of those counties have more icing than south and east. If it becomes apparent that at least 1/2 of the county is has significant icing, power outages, downed trees and powerlines, they will close with no delay. Even if the temp rises to 33 or 34, that is not going to do much to melt 1/4 inch of ice in a few hours, especially when atmosphere is saturated and unable to soak up additional moisture.

Frederick/Carroll/York Counties and Southeastern PA Schools: Widespread closings and delays as these regions will be locked into the freezing rain for most of the night. 1/4 to 1/2 inch of ice will be common and some areas may see up to 1" which could bring down high tension transmission lines and damage towers.

ANALYSIS BEHIND THE FORECAST

Dec 3E Temps

The real issue is going to be this expected changeover from frozen to liquid precip in the overnight hours. I have some big problems with the plan being purported by the news and weather channel. News anchors always seem to overfocus on that magic 32 degrees, because they all report on it by saying..."So if we can jjuusstt get the mercury to creep a little but above 32, we'll be in better shape, right?" You know as well as I it is not that simple. Sure the 2 meter level temperature (what the temp is at 6 feet above the ground) might be 34 or 35, but without the sun in play and nighttime coming, bringing the air temp to slightly above freezing does not alleviate at all any significant icing problems. It will take a prolonged period of 6 or more hours with rising temps to get real melting in areas where you experience more than a light glazing of ice. This is why I firmly believe many Baltimore Metro Schools will be at least delayed 2-hours Friday and many northern areas may be closed. Take a look at the air temperature profile for Thursday afternoon. Another fun site to analyze current road conditions is the Maryland Dept of Transportation's interactive "Roadway Weather" which reports current roadway temps and status.

Brief update later tonight before bedtime, and I'll definitely be back online tomorrow around 6AM.

Wednesday, December 14, 2005

THIS ICE WON'T BE NICE

Hey everyone I am sorry for the silence on Wednesday!! I am so frustrated. My blasted comcast cable modem was offline all day and I was totally disconnected from the internet. I had almost had seizures for being so unaware of the outside world, and The Weather Channel was not any help..the loca forecast seemed to conflict all day what the on air mets were saying. I am now clunking along with "super fast AOL 9.0" as a temporary backup at $6.00/hr. Hope to have problem fixed and a more detailed update out tomorrow, especially for readers from PA on north to MA. This post is primarily for first stage of the storm... in MD, VA and WV.

STORM SUMMARY REGARDING SCHOOLS: Most areas in central and western MD will see precip begin as snow between 8 and 10 AM, then quickly change over to sleet, which should continue for a long period... perhaps until 3 PM, when it will become freezing rain. The exception will be areas near the Chesapeake Bay. "Border towns" such as mine (Dundalk) that border water may escape significant icing, but travel just a few miles west of here and I think much of Baltimore City and Washington and all points north and west of I-95 will be a skating rink by Noon. Northern Baltimore County, Frederick, Carroll and even rural parts of Howard County are going to experience homeowner's insurance rate-busting ice accretion of 1/3 to 1/2 inch. Rule of thumb on this storm: It will get worse as day progresses.


I am still leaning toward a 4-day weekend for metro Baltimore schools, and this is NOT hype-casting or wish-casting. Most other districts in affected areas of PA, NY, and NE will be closed or delayed Friday only. This will be one of the toughest calls schools have faced in a long time. However, with half of Baltimore County under an "ICE STORM WARNING" (never seen that in my whole life) and even the Winter Weather Advisory sounds so scary I don't even want to venture out on my front step...Mother Nature might be making the decison for us. However, I see problems with the forecast and here's my concerns/scenarios:

1. First Scenario: As of 12AM Thursday morning, our storm is still way south and will take precip a while to reach and begin coating ground in Baltimore due to dry air factors. However evaporative cooling factor may impede a changeover to rain later in the day even for areas near the water. As a result, schools open on time, hedging against the hope that the atmosphere will warm enough to prevent an early dismissal before 2 PM, and hope that computer models overnight decide to back off the calls for 1/4-1/2 inch ice.


2. Second Scenario: However, an early dismissal would wreak total havoc with parents in that now they are fighting their frustration AND leaving work early AND icy roads AND bad traffic AND reduced visibility as conditions will be real bad county-wide by noon Thursday... and they'll ask "why didn't schools just close today."

3. Third Scenario: Tough spot for Districts ... but they "take one for the team" and close outright on the HOPE that the forecast for all this supposedly terrible ice coming our way actually shows up? Or will it be an embarrassing situation where schools close and the ice never materializes until...say 4 PM? (remember the dire Heavy Snow Warning of late Feb 05, the snow started at 10 AM, did not stick until 3PM). It is a difficult call to make anytime there is inclement weather as you WANT Mother Nature to make it obvious to everyone the basis of your decision. The hard part comes in trying to second guess as to what she will do in order to best protect your families, students and colleagues.


Based on the expected severity of this... I am leaning towards an all-out close for most of the Balto Metro area...incl the city, Howard, Frederick, Carroll, Harford. Cecil is not under a watch or warning so they might eek out a day. Then again, Howard County might just roll the dice like they always do. But I think districts will pull the trigger just for fear that students/parents/teachers may be caught in an ice storm on their way home..whether it is noon, 2pm or 4pm. Friday could end up being a 2 hour delay (expect for places like Frederick County MD on north to Bucks Co PA...you are certain to close on Fri). Read the text of the ice storm warning and it will terrify you if you have small children who normally walk home from school under trees or powerlines. I certainly hope that kids DO NOT go outside during the storm because real bad things can happen real fast in ice storms.

Thursday morning, provided I have been granted "extra time" to forecast, I will post a hourly precip estimate and storm track analysis for phase 2 of this event.. from PA to NE.

Tuesday, December 13, 2005

4-DAY WEEKEND? DOES IT GET ANY BETTER?


Dec 3C

Special note to non-public school readers: Since certain schools block any blogspot.com sites, I am beginning to reorganize the content of this site under a new address: http://footsforecast.typepad.com. In honor of my hard-working school colleages, Each post is actually going to appear on that site first, then I will copy, paste and edit for this second. So if you want an updated scoop on the latest, go to the typepad.com address first. Eventually, once I get all the formatting changes transferred, which may take several months, I expect the blogspot.com site to be discontinued, but I will leave the new address listed prominently for anyone who does not check back frequently.


12/13 9:30 AM UPDATE: Computer models are indicating a slower onset of the precipitation in the Mid-Atlantic region Thursday morning, especially along the I-95 corridor. This means when the precip does begin to fall, it will have a deep layer of cold air to penetrate, and with many road and ground surfaces likely to be in the 20's by daybreak, several hours of snow and freezing rain are expected. Mixed precip should begin between 4 and 6 AM, continuing until at least 10 AM, followed by a gradual changeover to freezing rain, sleet and perhaps rain south and east of I-95 cities. Then as the secondary Low develops heading northeast toward New England, cold air will be drawn southward behind the storm and into the Baltimore-Washington area, turning any remaining moisture back over to a brief period of snow before ending, as well as freezing over what did fall during the day. Tonight, Winter Storm Watches will follow the current Special Weather Statements.


1. WHAT ABOUT SCHOOL? The situation presenting itself regarding school on Thursday will be one of either...


A) "Do we get them in before it starts?" (which is possible given that computers have continued to slow down the onset);


B) "Do we go with a 2-hour delay and then re-evaluate at 7AM?" (which might cause more problems than it would solve in that the later school starts, the more likely buses and walkers would be caught in a period of heavy freezing rain), or everyone's favorite default solution...


C) "Do we outright close because by 5AM it will be apparent that road conditions are going to deteriorate as the day progresses?"


Actually the most logical and scientifically appropriate choice is...

D) "Let's open 2 hours early to avoid the precip and the traffic!" I'm up for it, any takers? Either way you slice this storm, it will be a dicey call for administrators and commuters. If you must travel, plan on a lot of extra time as freezing precip is expected during the morning AND evening commute Thursday.

2. WHAT'S THIS ABOUT A FOUR DAY WEEKEND? I would be remiss if I did not give you the full story, and it is plain to see why this could happen if you simply consider the NWS forecast for, say, Towson, MD. Cold air sweeping in behind the departing Thursday storm will change any liquid precip in the air or on the ground back over to frozen, and overnight temperatures will drop low enough to produce a potential skating rink for Friday morning. Please understand this is not hype-casting or wish-casting.If anything I think many of us would wish for snow instead of ice (translate: you on the sofa with a heating pad and Ben-Gay after an hour of scraping 1/4" ice off your car). This same scenario happened in late January 2004, and many Baltimore area schools actually ended up with a 5 day weekend. Remember that one? It was the same time quarter grades were due. I'll bet dept chairs and administrators remember it better than teachers do!


3. WHAT'S THIS ABOUT SOME PRE-CHRISTMAS BLIZZARD? Not enough reliable information available at present to make a reasoned call, but yes, Virginia, there will at least be snow on the ground at Christmas. A developing story so check back later for updates on this.

Monday, December 12, 2005

AN ICE STORM COMETH?

Dec 3B

Forecasters and computer models are growing increasingly concerned over a complex winter weather situation developing in the Mid-Atlantic and Northeast for the Wednesday night-Friday night time period. The most recent indication of this is a Special Weather Statement issued by the Baltimore/DC NWS Office Monday afternoon. Emphasis is on the word COMPLEX. Let me break it down for those of you wrangling over what this may mean for schools, especially in Maryland. (Please note that for the time being I will refrain from specifically referring to certain larger K-12 educational institutions in the post by name for fear that doing so may result in this website being rendered unavailable to you at a public school)

1. WHAT IS LIKELY TO HAPPEN. A multiple Low pressure system will approach the Mid-Atlantic at same time that a fresh supply of cold air is becoming available from Quebec, Canada. Recent snow cover will serve to reinforce this process. The two air masses will clash starting Wednesday night and produce a wide range of precipitation types, including snow, sleet, freezing rain, sleet, fog and rain. However, the orientation of the Lows is such that the I-95 corridor is likely to see precip begin as snow, sleet and freezing rain, then in the mid-morning hours on Thursday, it may change to plain rain as the Low(s) will pass close to or over major cities. The timing of this is critical as it relates to the Thursday morning commute. At present it is expected the cold air will retreat slowly, allowing for a slower changeover of the precip from frozen to liquid. This scenario would result in Maryland, WV and Western/Interior Virginia schools being disrupted on Thursday morning with at least a delay.

2. WHAT IS NOT LIKELY TO HAPPEN. The Lows take a more inland/southerly track that would not scour out the cold air prior to arrival, and what was going to be an ice/rain storm becomes a surprise snowstorm with 6-12 inches on Thursday. The dynamics of this storm are much different than Dec 9, so do not expect this to happen. Interior sections of PA, western MD and NY will see a moderate snowfall as depicted by the graphic above, but not the major I-95 cities.

3. WHAT IS THE HANGUP OVER THIS? If the frozen precip Wed night takes longer to changeover Thu AM, Maryland schools may be looking at a "2 hour delay...reevaluate at 7AM" situation which happened in late January 2004. Continue checking back on this developing situation, as further posts will elaborate and analyze the storm in more detail.

Saturday, December 10, 2005

LOOKING BACK ON A NICE STORM...

Dec 2D



15.1 Inches in Concord, NH as a reminder of why this powderhound just loves snow. Maybe not the "clearing off the car" bit, but there's something special about being taken captive by Mother Nature for a few hours in a big snowstorm. Neither the richest nor the most powerful person in the world can do anything about it, we're all in it together, so the best solution is to just revel in the beauty and enjoy the free time that some of us get when you see this out your window. I know I did, and in a few minutes I'm going out to do some more reveling "in it" with my daughter...literally. Credit for this photo goes to a meteorologist who posted it on the Eastern US Weather Forums, a great source of wide-ranging discussion on every aspect of weather analysis you could possibly imagine. I don't post on this forum, I just read it occasionally for reference and entertainment!


...LOOKING AHEAD TO THE NEXT STORM

Dec 3A
The pattern currently dominating U.S. weather is likely to produce one or two more storms, but they may not produce as much snow for the Northeast Corridor as some of us would like. At least we can enjoy the pre-storm analysis paralysis (or paranalysis for short). The first GFS incantation of the next storm looks to be a blase drifter to the East Coast with intermittent snows. For the Thursday 12/15 period, other models show a Great Lakes cutter, and still others point to an Appalachians runner. Let the speculation games begin!

Wednesday, December 7, 2005

THE FINAL WORD ON DECEMBER STORM # 2


(SUBTITLE: THE "ON AGAIN, OFF AGAIN SNOWSTORM")

FIRST GRAPHIC IS THE PROGRESSION OF ACCUWEATHER'S SNOW CALL OVER PAST THREE DAYS, SO YOU CAN SEE WHY YOU'VE BEEN GETTING WHIPLASH TRYING TO UNDERSTAND HOW MUCH SNOW IS SUPPOSED TO FALL.

Dec Storm 2A

SUMMARY: Winter Storm and Heavy Warnings blanket the Map from Ohio to New England, and all the elements seem to be in place for a quick hitting, fast moving Mid-Atlantic and Northeast Snowstorm. While this could end up a surprise 6-12" bonanza for the major cities, it may only come at the very last second and in the daybreak morning hours on Friday. Overall accumulations for most areas under currently under a warning will range closer to 6" than to 12". The snow will fall in a short time period, from midnight Thursday to 9AM Friday, and by afternoon, the sun should peek out before setting on a cold and snowy wind-swept landscape. Many schools will close as crews quickly discover how difficult it will be trying to keep up with snowfall rates of 1-2 inches per hour, and the morning commute on Friday will be very hazardous and nerve-wracking for those who have to venture out. Analysis follows below and snowfall accumulations to be posted this afternoon.


SECOND GRAPHIC PROVIDES A BIRDS-EYE VIEW OF WHAT IS GOING ON IN THE ATMOSPHERE TO GENERATE THE INGREDIENTS FOR OUR STORM

Dec 2B

WHAT FAVORS THIS STORM TO BE A BIG SNOW-MAKER:

1. Plenty of cold air in place. Lower than normal sea-surface temperatures off Mid-Atlantic coast helping to enhance and stabilize position of high.

2. Impressive southern jet stream tapping ample Gulf and Pacific moisture. Link.

3. Neutral NAO will allow storm to make a gradual East-Northeast jog as it moves toward coast, instead of bypass or get suppressed too far south. This kind of “slight ENE angling” is what we saw in the Feb 2003 blizzard and similar storms.

4. Fast moving storm will “moistent the column” overnight and by daybreak widespread heavy snow throughout region from Virginia to northern New Jersey, then moving toward NYC by mid morning and Boston by afternoon.

5. Terrible timing for Friday morning commuters…below freezing road surfaces given that snow will be falling in overnight hours means it sticks on contact, creating instantly slippery and hazardous conditions, as well as sharply reduced visibility for drivers in morning hours.

6. Perfect timing for students and teachers looking for a 3-day weekend. You can bet your boots this will close most schools from central and northern Virginia on north and east including the WV panhandle, central and eastern Maryland (Baltimore and DC Metros), Central, SE and Eastern Pennsylvania, the Philly Metro schools might be crazy enough to start with a 2-hour delay. NYC Schools will have a tougher call as snow is coming later in the day, they might end up with early dismissal.

7. Perfect timing for those who want Saturday to recover and dig out, as storm will be long gone by Friday evening, and sunshine and slightly warmer temps return Sat.

WHAT COULD PREVENT THIS STORM FROM BEING A BIG SNOW-MAKER:

Check the Baltimore/Washington NWS Forecast Discussion, they post a small list of criteria for your big time snowstorm, and sadly there are some elements in place to PREVENT this from being the storm you want it to be.

1. Placement of the High…is not to the North or West (as in the classic spot of southern Ontario or upstate New York. This kinds of High can drill a cold air damming situation in front of the storm. Granted we have cold air in place, but High is in the WRONG place.

2. There’ll be considerable mixing with and changeover to sleet/rain in southern parts of the storm, lower southern Maryland, eastern Virginia. This almost always robs a storm of energy which generally cuts down on snowfall for everyone.

3. Balt/DC NWS said it best…when there are multiple lows in play, this also reduces the likelihood of big snow because the energy required to concentrate on one big cyclogenesis is spread too thin among several systems.

4. Fast-moving storm will limit the amount of time it has to drop snow. That alone is going to knock a few inches of everyone’s 12 inch expectation.

5. Several low pressure systems have well over 1000 miles to cover between now and Friday morning, and must undergo a lot more transformation to become the blinding white snowmonster some are wishing. Granted you can see the moisture inflow from the Pacific and Gulf, but that moisture has to interact with the northern branch of the jet stream just right in order for those heavy snow warnings to materialize.

6. Low-level warming as a result of that return flow from the departing high I mentioned in earlier post. If we start to see southeast winds during the storm, this will first raise upper level temperatures, then surface, inducing a mix and changeover, which robs the storm of energy, cutting on accumulations for a large area. Also consider that snow-to-liquid ratios in the I-95 corridor will not be 20- or even 15-to-1 but more like 10-to-1, which means whatever the QPF (liquid equivalent forecast) is for your area, that's likely to translate pretty easily to the inches you'll see.

AFTER I RETURN FROM SETTING UP TODAY'S LESSON PLAN AT SCHOOL, I WILL POST MY ACCUMULATION FORECAST, AS WELL AS THE GRADE FROM LAST STORM.

Tuesday, December 6, 2005

THIS MIGHT NOT BE THE ONE!
UPDATED WED 6:30 am
Dec Storm 2


WEDNESDAY MORNING UPDATE:
Well lookey what we have here...last night, a potentially bigtime snowstorm was on the books. What one good night's sleep will do, huh? (for NWS forecasters, not me). It seems NWS has ramped the storm back down to earth overnight, and mostly removed words being used yesterday like,"dangerous, very significant, etc...6 or more inches." For example, Balt/DC NWS was really sounding the alarm last night, and now has an innocuous "light to moderate snow" Special Weather Statement. Cancelling the hype was a good idea, because there remains the possibility the Ohio Valley Low and the Southern Rockies Low never link up the way we want them to.. and the Mid Altantic High nudges offshore more than we want it to. Throw in the fact that this storm is moving faster, thus limiting time for it to drop precip. Result? Our big storm never materializes and we get KaDUDa # 2. That's why I and other online forecasters were hesitating. Granted Winter Storm Watches may still be hoisted for a large area, but we may very well see a repeat...as in Snow Advisories and a final tally around 4-5 inches. I'll bet when Accuweather updates this AM, they dramatically scale back the 6-12 inches they painted for the Mid-Atl and NE on Friday. You know I'm a born and bred powderhound, and I hate to be a party pooper, but I'm not going to get you all riled up for a storm that might not live up to the hype.

Let me add that while many areas may not get the 6-12 inches we hope for, the timing of this will be that even 5 inches occuring overnight from 9PM to 6AM will be just perfect to cancel many schools for Friday from Virginia to New York City and everywhere in between. Main reason is that this will be a quick snow, and crews will not be able to keep up, thus they will give up until it is over. Then you'll be able to roll over and go back to sleep. Now that's a Happy Friday! (Forecast note: I will be out the entire morning delivering a toddler to a grandmother, so no updates until at least 1pm.)


TUESDAY EVENING POST:
Already the drumbeats have started for another major winter storm and Special Weather Statements are starting to fly out the gate. I am still digesting and reviewing the previous storm to see what went wrong, as my grades are coming in about a D- average on snow totals (although I did score big time with Richmond, 4" forecasted and a result of 4.2" !). We have all seen the pre-storm hype end up bigger than the storm itself, so I am going to look over the data for this one more closely. The interesting thing favoring the powderhounds is that both Accuweather and the National Weather Service are sounding the trumpet for a potential major snowfall in the Mid-Atlantic and up I-95. Keep in mind the Dec 5 Dud did not officially qualify as an "I-95 Special" as no one along my favorite highway saw at least 6" (sorry, Ocean Twp NJ's 6.7" does not count). A true-blue I-95 Special is where all the megalopolis cities (and their surroundings counties) receive a good solid 6+ from DC to Boston. This storm appears to have the potential to deliver that as there will be plenty of cold air in place, and radiational cooling in advance of the storm caused by Storm 1's snowfall will help to keep temps down right up to the onset of snow Thursday night. I am not ready to issue preliminary accumulations as I have to review the QPF maps, but the elements are slowly coming together. In fact, before we go over the numbers on Storm 2, we will first discuss what are "the elements" required for a good shovel-smackin' snowstorm along the East Coast.

Some of the basic items I and every other serious forecaster looks for is the classic dome of High pressure parked over New England or New York. The current realm of blue skies shining above is that High, except that it is nudging far enough south to create the tell-tale "cold air damming" down the east side of the Appalachians. This bodes well for powderhounds in the southern portion of the Northeast Corridor (from Richmond to Philly). However, what concerns me is the trajectory of the storm, whose end game will be the combination of several Low pressure systems coming together by Friday morning. It is possible this storm will move just simply straight east, and though it will throw a big shield of snow out for hundreds of miles, it MAY miss the northern sections of 95 from Connecticut on north to Boston. Go run the computer models I have linked to the right to see what I am talking about. For those in interior sections, such as West Virginia, central Virginia, central and eastern PA, and especially the mountains of NC and SC, depending on your location, upsloping may yield higher snowtotals for you, along with a significant ice storm in the Carolinas.


All the way around, this storm looks to be a block/backbuster event, PROVIDING that the key element, that High Pressure dome, does not detach itself from the picture too soon, right? That would allow a return flow on the backside to link with the onshire flow of the approaching Low, and thus our storm starts as snow and changes to all rain for the big cities. I have seen that kind of situation before...we got all excited about a big storm coming from the MidWest, only to have our 4-5 inches get all washed away as the warm front passed over.
THAT's the piece I want to investigate further before I sound the trumpets on a 6-12" Early Season I-95 Kahuna. Yes, I am resurrecting that term because this may definitely qualify as a Big K.

Sunday, December 4, 2005

HAS IT FINALLY ARRIVED?
OR IS IT ABOUT TO LEAVE?

Dec Storm 1

12/5 LATE AFTERNOON UPDATE: Am back from doctor's visit and looking over update data now. What a puzzling storm! At 1:20 PM today we are in White Marsh, MD at our children's doctor office, and a nurse pokes her head in the door to mention to the attending nurse with us that schools are closing early. We quick glance outside the window wondering if something huge changed in the 2 hours since I had been at the computer. What do I see? NOT A FLAKE! So I think, "maybe just our area has no snow, and everyone else is being clobbered." I hear on the radio en route home something about "4-6 inches for Baltimore" then I hear on a different station something about "1-3 inches by tomorrow morning." My wife, who is from northwestern Pennsylvania, often kids me about how ridiculous all this really is...NOT EVER would have her schools (Crawford County) near Erie closed early for no snow in the sky. So in a futile attempt to put some science on the face of this storm, I will soon explain the graphics I assembled above and try to make sense out of a seemingly senseless snowstorm. I admit we will have a long way to go to reach verification of the amounts I predicted, but we'll just let it go for now and see what happens. For those who check-in frequently, please post your local observations in the comments.

12-5 LATE MORNING UPDATE : I have a strong suspicion the storm is coming farther north and west than anticipated, and the cone of heavy snow will be shifting to include the I-95 cities of DC, Baltimore and Philly. Not because I like to wishcast, but in looking at the water vapor imagery loop it is clear the Eastern Mid-Atlantic is fully enveloped in the bright white, and the overall tilt of the moisture riding up from the Gulf and Pacfic says to me that the moisture stream is exerting more of an influence than the dry slot behind it. I think the Snow Advisories will be changed to Winter Storm Warnings and amounts will be upped a few inches, probably settling on 4-8" for metro areas. I am going to leave my amounts in place for now until I can get more data. Have a double doctor appointment for both childs at 1:15 PM so no updates until late late this afternoon, probably not before 5 PM. Overall this means that WV, most of VA and south central PA will be in on the action, as will metro PHL and NYC. As for Boston, we'll see how the secondary forms and what it does before I go out on a limb there. Central NJ...sadly but if the action shifts N and W you might get the sleet/snow mix which will cut down on your accumulations. Will be a fun storm to watch. I will take kid pics in the snow and post here. Will also be revising portions of earlier post...


WILL IT BE A "THREE-PEAT" ?


Two of the last three years have featured significant snows occuring within the first 7 days of December across the Mid-Atlantic and Northeast. I use the Baltimore Metro region as my point of reference because that's where I have lived since 2001. Consider:


DEC 5-6, 2002: DC, Baltimore and Philadelphia, among many other areas, receives 7-9 inches in a blockbuster first snowstorm of the season that closes all area schools for 2 days (Thu and Fri). This storm kicked off a very productive and snowy season that culminated in the February 2003 Blizzard. This month was a classic example of the saying, "What happens in December, Winter will remember."




DEC 6, 2003: Baltimore and the Eastern-Mid Atlantic in general receive for a second year in a row (on the same exact date), a season opener significant storm delivering 6-7 inches. The main event of the winter (in Baltimore) was a 3-day ice and snow storm in late January 2004, and rest of the season was punctuated by several mini-snows causing a higher than normal number of 2-hour delays for schools due to icy conditions.


DEC 2004: The opening storm of the month was initially thought to be snow and turned into an all-rain Nor'easter event. The rest of the winter for most of the Mid-Atlantic was very disappointing, except for two major storms. The January 21-23 Blizzard was the most notable event of the winter, covering a large area with 6-30 inches from Washington, DC to northern new England. The last week of February was the second major event for the Baltimore area, delivering 4-6 inches in a first round, followed by a few more inches in a second round several days later. Overall, last winter was more remembered for the extraordinary snowfall in New England as that regon received the brunt of most storms throughout the season.


WHAT IS THE POINT OF REVIEWING STORM HISTORY ON THE EVE OF THE FIRST BIG STORM OF THIS SEASON? I think it is important to see the pattern that has been developing the past few years, especially when you factor in the influence of the recent hurricane season. Elliot Abrams of AccuWeather posted on his website last winter a study he conducted of first snowfalls in Philadelphia. He discovered that in seasons where the first snowstorm produced 7 or more inches of snow, the remainder of the winter (in that region of the Mid-Atlantic) saw frequent and productive snowstorms. In seasons where the first snowstorm was less than 7 inches, the remainder of the winter was lackluster and disappointing (at least for powderhounds.)



What I'm getting at is that if history is an accurate guide, this storm had better:
A) live up to the billing it's received so far, and deliver 6-8 inches for BAL and PHL
B) Change the trend so that the first storm does not serve as an indicator of future storms
C) Fizzle now while we are still ahead of the game, so we can try again next week
I have read through all the models, discussions and predictions for this storm all across the internet, and a few things stand out that are the basis of my forecast. I want very much to back up my analysis with detailed links and reference to all the sources I've used thus far. However that will have to wait until later Monday. For now I will just give you the First Call and then refine it with analysis tomorrow.



1. JUST THE FORECAST


This projection assumes a snow onset by 12 noon Monday. in all areas under Winter Storm Watches or Warnings. In Northern VA, DC and Baltimore Metro areas, schools WILL be in session Monday and are NOT LIKELY to have an early dismissal UNLESS it becomes apparent the storm is moving in faster than anticipated. Unless there is a major change in track or eventual intensity of the storm, I expect most schools in the Watch area to be CLOSED TUESDAY, and reopening Wednesday with a 2-hour delay, depending on the amount of snow. 8 or more inches is going to guarantee schools close for 2 days due to time it takes to clear parking lots, and just the shock of the first major snow arriving so soon.


STORM GRADE ACCUMULATIONS (BY 6PM Tuesday 12-6, verified by NWS Spotter reports and official measurement sites.)



VIRGINIA: Roanoke...9 / Richmond...4 / Charlottesville...7 / Washington...5





MARYLAND: BWI airport....5.5 / Towson...4 / Columbia...6 / Dundalk....5




PENNSYLVANIA: PHL airport...6 / Paoli...4 / Bucks County...5 (will add more later)




NEW YORK : Central Park...5 / JFK airport...4


NEW ENGLAND: Logan Airport...7 / Woburn, MA...6 / Taunton, MA...7


(I will add more tomorrow. If you want your location include, request such in the comments.)


2. ANALYSIS BEHIND THE FORECAST


3. PHILOSOPHY AND RATIONALE

Saturday, December 3, 2005

BORN ON THE LAST DAY
OF HURRICANE SEASON?
Am I talking about Hurricane Epsilon...
the 14th named storm of this record-smashing season?

Epsilon

(Actually, no...I am really referring to:)
THE LATEST LITTLE FOOT
Johns Hopkins University's Bayview Hospital
Baltimore, Maryland

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Now you know the reason this site has been offline for so long. I apologize to all the loyal readers out there whom have put up with my silence and lack of communication or forecasts for over a month now. As you can imagine, we have been heavily immersed in baby preparation, and it paid off. Mommy had an emergency C-section, but all went well and we have a beautiful baby girl, to complement our already darling first little girl who is thrilled about her new baby sister.

101_1257


Everyone is home now and resting peacefully after 4 days in recovery. Those of you with several children know better than I how challenging it can be to keep sane in a busy home full of rambunctious kids. But at least for this holiday season, we will be thoroughly enjoying the relative calm of a 2-year old and a 1-week old. As I write this, I am blessed to have both children asleep, as well as Mommy napping too! (I'm sure that will change very soon.)

100_1312


Kaselyn proved to be the catalyst I needed to get the forecast site back on line. Now I am slowly finding out that we (as in the I-95 corridor and interior PA, VA, WV) might have our first big snowfall of the season on December 5-6. So I am very excited to have all my ladies back home, but equally as excited that we might get to have a real snow at a time when I can enjoy it while I am off for school. Jayla, (my first daughter) has her first Christmas program this evening, and after that it will be an early bedtime for everyone. I usually get more motivated to begin forecasting again when it becomes more evident that MY FAMILY will be among the happy recipients of a snowfall significant enough to close school. The double bonus right now is that a snowday while I am on my 2-week paternity leave does not count against my leave time, nor do I have to write lesson plans for the substitute! I can just stay home, enjoy the snow, take pictures, and spend quality family time. We feel truly blessed and my best wishes to your families that you will feel these same kinds of blessing this Christmas season.


NOW, with no further delay... I return to the job you've all been waiting so patiently for. SNOWSTORM FORECASTING. I am looking into the latest computer model projections for this apparent new storm on the docket for Sunday night into Tuesday. While I am out this evening, take a look at the latest QPF maps for Sat-Sun and Mon-Tue as well as the latest round of Special Weather Statements to see why I think it looks good for the Mid-Atlantic and Northeast to get their first I-95 special of the year.