"There you go again."
- Ronald Reagan to Jimmy Carter in the 1980 Presidential Debate
6:00 PM TUE 2.23.2010 (First update 3:45 PM) According to the National Weather Service, the game is on. Winter Storm Watches posted throughout the coastal Mid-Atlantic will take effect tomorrow evening into Friday for most of Maryland west of the Bay, all MD counties on the eastern shore, as well as Delaware, metro Philadelphia and southern New Jersey. As we outlined on Sunday and Monday, our suspicions of a "surprise" snowstorm are now all but certain; the real questions now become: (1) How much; (2) When it starts; (3) How long it lasts.
Preliminary projections by 9th grade students at the BCPS Crossroads Center point to at least .70" of liquid for BWI airport as a representative location for central MD. Calculating on a 15:1 snow ratio points to preliminary totals reaching 8 or more inches across the I-95 corridor from Washington to Philadelphia. Significantly higher amounts are possible for interior Pennsylvania, New Jersey, upstate New York and the Delmarva. Largely due to the potential "retrograding" nature of a low pressure system projected to resemble a hurricane by Thursday night (supporting links pending). Another case of "there you go again" ? Perhaps, but this time we all better have our game on, this is no drill.
Updates posted tonight on facebook and in the Winter Stormcast Zone. Our storm grade totals for the period 12AM Thursday to 12AM Friday will be posted in the Winter 2009-2010 Storm Data Sheet by Wednesday evening, available for download to see clearly the time and amount of projections made prior to the event.
6:00 AM TUE 2.23.1010 The seemingly endless parade of winter storms through the south and northeast has another act lined up already. This complicated setup will send the swath of warnings across the I-10 corridor into Dixie, and along the Mid-Atlantic and Northeast by Thursday. There is increasing potential for the system to rapidly intensify by Thursday night once reaching the DelMarVa coast. By Friday morning, coastal areas of the Mid-Atlantic such as New Jersey may be experiencing a surprise significant snowfall coupled with winds in excess of 30 mph. An overview possible impacts for Mid-Atlantic and Northeast Wednesday into Friday:
WIND Regardless of how much snow falls, a possible pressure fall to 972-980 mb would be more intense than the February 9-10 Blizzard. Some computer models as shown via our Penn State University "E-wall" resources suggest winds near tropical storm force in much of Maryland, with gusts near hurricane force along the DelMarVa coast by Friday morning.
SNOW At present, the areas at highest risk for a possible surprise snowfall Thursday into Friday include southern New York, New Jersey, Philly metro, southern PA, central PA, Del-Mar on the peninsula, northeast / northcentral Maryland and even northern Virginia. Our concern is snow-to-liquid ratios, given an increasingly colder airmass, may approach 20:1. This link to snowfall projections as issued 7 PM Mon shows only an extreme scenario, but the liquid data is undeniable. With this system parked near the Gulf Stream for over 24 hours, it is entirely possible that moisture transport produces snowfall totals at or above significant criteria, and may certainly surprise many people expecting just snow showers.
RAIN Strange as it may seem, eastern New England such as the Boston area should be in the warm quadrant of this potentially explosive low for a time, receiving heavy rain the same time New York City is pounded with snow.
NEXT UPDATE Our team remains focused on this significant storm potential, and will update around 12 noon today with additional facebook reports this afternoon.
No comments:
Post a Comment