There's another surge of warmth coming out of the lower Mississippi Valley and though the Tennessee and Ohio Valleys into the Northeast today. It'll push temperatures much above normal, with some places getting to 80 or better, close to average highs for early June in some cases.
Looming over the horizon, though, is a nasty storm, one with evil intent. There are three pieces to this puzzle that, when put together in the right way, will help develop this storm and bring much-needed rain to much of the mid-Atlantic and Northeast. The problem is that it's coming on a weekend. That we can deal with. After all, it's still April, right? We've enjoyed such fabulous weather that we can sacrifice a weekend early on for the greater good.
There's also another problem. It may not be all rain. Yes, that's right. Snow is possible. It's been bantied about for days now, given the expected strength of the storm, and the chill of the air coming into the upper level trough that will help give rise to the storm this weekend. The question has always been where the storm would track, as that would have a direct bearing on who is on on the chance of the white stuff, and who escapes without injury, no questions asked.
Here's the upper level forecast off the 12z Friday 20 April NAM:
One piece flying across the Lakes will drive an initial cold front toward the New England and mid-Atlantic coast later tomorrow and tomorrow night. The southern split brings the front the Texas Coast tonight, and drives the front eastward across the Gulf Coast tomorrow. That'll set the stage for the storm to rise from the ashes of the trough out of the northeast Gulf and head up along the front along the Southeast Coast tomorrow night and Sunday morning:
The third piece is coming over the top of the ridge toward the Upper Midwest. That system dives into the developing trough, and basically gives a shot of sugar to the developing East Coast storm. This, in turn, causes the storm to rapidly deepen on its trek northward, and by Monday chances are it winds up somewhere over upstate New York.
As the storm grows stronger and deeper, it will intensify the chill to the west of the track, and it may well cool the column of air enough to bring snow to the ground. The areas that right now seem at risk cover the central Appalachians, perhaps to West Virginia, and certainly points north into Upstate New York. This late into the season, the higher elevations have a distinct (dis)advantage over the valleys, so that's where the snow would cause the greatest problems should it come to fruition.
Complicating matters is that the trees are already displaying a growing leaf canopy, and that spells big trouble should the snow be heavy enough for a long enough period of time. Again, this is a little early to be precise about the track of the storm and who would be at the greatest risk of this kind of event. We'll definitely be all over it this weekend here at AccuWeather.com, so be sure to check out the latest stories and thinking plus updated maps throughout the weekend!
One thing is for certain - the weather later this weekend through the first half of next week will be decidedly cooler than it has been for quite some time, and shows little signs of returning to the warmth of today for at least a week, if not longer.
Two systems will delay the onset of warm weather in the Ohio Valley and the East over the next week or so, but then it should get warm all across the country heading into the Memorial Day weekend.
A turn to much colder air over the Northeast and mid-Atlantic states will set the stage for a rain and snow storm later this weekend before it turns much warmer later next week.
It's warm now, but will turn much colder this weekend, with a storm threat later Saturday into Sunday. Warmth will return by the second half of next week.
Though it is cold now east of the Mississippi, with a couple of opportunities for snow into the weekend, a blast of warmth is due for much of the country east of the Rockies next week.
Warm air will once again surge eastward from the Plains to the East Coast this weekend and early next week. A strong storm next Tuesday and Wednesday will then be followed by colder air later next week.
A storm in Southeast Texas will generate severe thunderstorms this afternoon and tonight, and some wet snow on its western flank as it heads into the Ohio Valley tomorrow.