Monday, 11:55 a.m.
I hate to be the bearer of what, for most people, is bad news, but our long-awaited warmup this week is going to be all-too short. In the Northeast, it will effectively amount to a one-day spike in temperatures ahead of a cold front Friday, then it will be all but over.
Now that I've thoroughly depressed many of you, let me at least give you some good news. After the storm comes through the Ohio Valley this afternoon and into tonight, then through the mid-Atlantic and New England later tonight into tomorrow, the arctic air will effectively be routed out of the region. While the air behind it won't initially be all that warm, it won't be bitter, and the temperature trend will upward west of the Appalachians through Thursday, and through Friday in the East.
To get there, though, we must first deal with a storm that is going to end up being a couple hundred miles farther south than was projected during the middle of last week, and the cold air preceding it much deeper and tougher to get rid of than was anticipated about five or six days ago. As a result of that, there's going to be a lot more snow much farther south that was thought of originally.
The 12z Feb. 17 NAM forecast is a little scary, quite honestly, as it takes this rather weak storm moving across the Midwest now and steadily deepens it tonight as it crosses the lower Great Lakes and northern Ohio Valley. A secondary area of low pressure then forms along the mid-Atlantic coast late tonight and quickly begins to deepen tomorrow morning as it heads northeast and crosses southern New England toward southeastern Massachusetts tomorrow. Here's the total precipitation forecast through tomorrow night from the NAM:
That implies more than 6 inches of snow could fall in parts of New Jersey, southeastern New York state, including most of Long Island, and much of New England. The scale is a little different when you look at the similar forecast of precipitation from this morning through 7 a.m. Wednesday, but the results are not too dissimilar from the GFS model:
The bottom line is this: the cold and snowy pattern will yield yet more snow through tomorrow before we get to hit the 'time out' button. By then, though, the snow pack will be quite extensive from the northern mid-Atlantic back to the eastern Dakotas. Here's what it looked like early this morning in centimeters:
Basically, we're looking at the 1/2-inch contour, then the 10-inch line, and the 20-inch line. And again, that's NOT including what will fall today through tomorrow!
With such an impressive snow pack, it will have an impact on temperatures in the coming days by denting the warmup some. I talked with another one of our bloggers this morning, Brett Anderson, who lives out in an area that radiates well, and his comment to me when he came in is that he wouldn't have anticipated it being as cold as it was this morning based on the pattern and your usual parameters. Given the fact there is such a deep snow pack, and Lake Erie is mainly iced over, and there's really no modification of air masses coming over the Great Lakes right now. So, as we go forward this week, milder air trying to move in over the deep snow pack is going to be modified, unless there is a really strong wind blow that can overcome that natural refrigeration from below.
The trough that comes through the Ohio Valley and Great Lakes tomorrow night, then off the Northeast coast Wednesday evening, will drag a weak cold front through the region, more or less slowing the warmup between Wednesday and Thursday. Then a much bigger storm will develop Wednesday night over the central Plains and cut across the central Great Lakes on Thursday. In turn, a strong cold front will come out of the Plains and across the Mississippi Valley, likely sparking strong to severe thunderstorms ahead of it.
The front will whip through the East on Friday, with a nice spike in temperatures Thursday night into Friday morning up the Eastern Seaboard ahead of the front. At the moment, I don't think the combination of rainfall and melting snow will be sufficient to trigger widespread flooding, but it is something to watch out for.
Behind this front, though, temperatures will fall right back to normal. And next week is looking cold from the eastern Plains and Mississippi Valley to the East Coast, with another storm threat during the middle of the week. In other words, some places might end up losing snow, only to get it replaced again next week!
Spring may be 31 days away today, but there's no support for a sustainable warmup beyond Friday. Enjoy as much of the milder weather as you can, because next week we go back to January.
The storm heading up through the Tennessee Valley into the Ohio Valley, then the Great Lakes tomorrow night and Christmas Eve will generate a lot of rain, but not much snow.
Several storms are going to be tracking across the country between now and the end of next week, with still some snow potential with at least two of the storms.
Storms will cross the country between now and Christmas, but the chances of a White Christmas are fading for many places in the East with time.
Two storms still have the potential to bring a white Christmas to areas that are currently snowless from the northern Plains and Midwest to the Northeast.
Two storms will track across the country between now and Christmas that could deliver parts of the country snow in time for a white Christmas.
Heavy rain is pounding California today, with flooding and mudslides. The storm in New England continues spreading snow across Upstate New York and parts of Pennsylvania.