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