Tuesday, 11:00 a.m.
A fast-moving, upper-level disturbance is in the process of carving out a weak low pressure area along the mid-Atlantic coast. Snow has swiftly moved across the mid-Atlantic region, with some rain in parts of Delaware at this hour! The snow will concentrate on New England this afternoon into tonight, with the heaviest snows from Rhode Island and eastern Massachusetts up into Maine.
There's also a trailing upper-level disturbance moving across Wisconsin into western Michigan at this hour, and it has helped to create a rather odd temperature configuration from the mid-Atlantic to the northern Plains! South of the track of the first feature, it's warming fast in Delaware and Maryland into Virginia, especially where there is some sun breaking through the clouds. North of there, it's cold. Then you have a trailing cold front extending from western New York down through northwestern Pennsylvania into western Kentucky. There's a nice spike of mildness in southwestern Pennsylvania ahead of this front, followed by more arctic air right behind it. Yet there's also been this odd warm wedge that came out of the Dakotas into southern Minnesota overnight in conjunction with the trailing feature. Here's the 10 a.m. temperature map:
And the Midwest:
This trailing upper-level feature will generate some snow showers this afternoon across the Great Lakes and Ohio Valley, but few places will get more than an inch of snow, and many won't get more than a covering. In fact, east of the Appalachians, with the boundary layer warming so much this afternoon, any precipitation that survives east of the mountains late this afternoon and early tonight could easily start as rain before the column cools to the point at which it may snow - assuming there's enough moisture left!
That's long gone by morning, and in its wake, it will be a chilly day tomorrow throughout the Northeast all the way back to the Midwest, but that's as cold as it will be for days to come.
The next main feature will come into the Northwest via British Columbia tonight and tomorrow. It will then dig into the Southwest Thursday, pulling colder air southward with it. The bulk of the cold air will go into the interior Northwest and northern Rockies at first, but then it will spread more east than south Friday thanks to the developing split in the jet stream. However, some of the cold air will make its way down the Front Range of the Rockies and to the southern Plains this weekend once the upper-level low comes out of the Southwest and a surface storm moves out of Texas and crosses the lower Mississippi Valley and heads into the Tennessee Valley.
This storm could have everything with it. I mean impressive warmth and reasonably high humidity by December standards is moving into the South and Southeast and trying to climb the Eastern Seaboard this weekend! Severe thunderstorms may erupt ahead of a cold front which is moving from the Mississippi Valley Saturday night and across the Tennessee Valley and Deep South on Sunday. There will be a fair amount of rain in the Ohio Valley into the central Appalachians, and perhaps even into the Northeast, and given the amount of warming that may accompany this rain, there may also be some flooding. And, of course, there will be some snow, though that may not be the main feature of the storm. Still, some snow is all but certain on the northwest flank of the storm, and that includes areas from eastern Oklahoma to Illinois and Michigan, including parts of northern New York state and northern New England. And even in these latter areas, that may also be accompanied some ice and rain for a time. Here's an initial broad brush snapshot of how this might look:
Yet another winter storm, though at least this one will be during the official winter season, which arrives Saturday at 12:11 p.m. EST. Up to now, all of this snow has been under the fall watch!
A quick shout out to a cycling friend from near Hershey, Pa., celebrating a birthday today! Beth, You got your snow - and a delay! Hope you can plan a great ride with friends in the mildness of Saturday! I'm jealous!
Good news, though. Only 55 days until 'Pitchers and Catchers Report.'
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.