Thursday, 11:25 a.m.
It's a tale of two storms today. While separate, they will have their own weather and problems associated with them. Combine them, and you have the makings of a truly historic storm. That's what we are staring at today. By the end of the day tomorrow, we'll see the two systems becoming one, from that point on, it will be a wild ride for 24 hours before the powerful storm eases away from eastern New England.
Here's the setup off the latest NAM model for this evening:
Three things jump off the page at me. The first is the feature over the Florida Panhandle, spreading rain with some strong thunderstorms through southern Alabama and the Florida Panhandle into Georgia at this hour. It produced a quick 2 to 3 inches of rain in Pensacola as it moved through this morning, a sign that it is a vigorous disturbance with a lot of moisture to work with as it ambles to the east-northeast this afternoon, then heads for the Carolina coast tonight.
The second is the weak-looking low trundling across the Mississippi Valley into the western Ohio Valley. Most of the precipitation associated with it is north and west of the low itself. In fact, there's been some sunshine already today from southeastern Missouri into Kentucky, southern Illinois and Indiana and even into southwest Ohio. And in those areas, temperatures are jumping into the 40s and 50s.
The third feature is the large high north of New England. It's really cold across Ontario and Quebec, with that cold, dry air in the low levels bleeding down into New York and New England. That's an important consideration going forward. Once the combined storm clears the mid-Atlantic coast late tomorrow and tomorrow night, it will run into that cold dome of air and try to wrap a lot of very moist air from off the Atlantic into and over that cold dome. And that's when the storm will go bonkers.
Figure it this way. Over New England tomorrow, temperatures will basically be in the 20s, teens far enough north. Meanwhile, south of New England, water temperatures are in the 40s. East of North Carolina, they're in the 50s. And over the Gulf Stream, they're in the 60s. In other words, you're going to have two storms merging into one over warm water, dragging tropical moisture northward and wrapping it around a deepening storm into and over some very cold air. The result? Jaw-dropping.
The models are all over the place, as you might expect. They bring those two storms together at different times and in different ways. The latest 12z NAM, for instance, deepens the storm quickly and just off the coast. It just dumps on southern and eastern New England to New York City, the Hudson Valley and New Jersey. Most of it is snow, except from the Connecticut coast to New York on south, where there would be a period of rain before the blizzard takes over.
On the other hand, the latest GFS does the deepening slower and farther east, leaving the heaviest precipitation more over southeastern New England up to the coast of Maine. The European, which has been reasonably consistent, looks pretty similar.
Each one has subtle differences that will make or break a forecast. There is a lot of high end potential with this storm, but there's equally as much bust potential, especially in and around New York City up into the Hudson Valley and back into eastern Pennsylvania, northeastern Maryland, New Jersey and even Delaware. Shift the storm track one way or another by 30-50 miles, and you could go from rain to snow with several inches of snow, to heavy rain followed by heavy snow and two to three times that amount of snow. And there are a whole lot of other possibilities, too.
In short, not everything is written in stone with the storm. If you want a crippling snowstorm, though, the best place to be is probably interior eastern Connecticut, interior Rhode Island and eastern Massachusetts, perhaps up to southern Maine. Most of those areas SHOULD get at least a foot of snow, and some areas may double that when all is said and done. The most likely places for more than 2 feet would be eastern Massachusetts and Rhode Island into northeastern Connecticut, but it doesn't exclude others.
The wind will intensify tomorrow into Saturday, the tides will come up and, when coupled with a new moon, will lead to a lot of coastal flooding in eastern New England and across Long Island Sound. Where there is a lot of snow, with 30- to 50-mph winds, you can bank on some wild snow drifts. Along the coast, those winds may approach hurricane force for a time late Friday night into Saturday. Power outages are probable with the weight of the heavy, wet snow becoming caked on things near that rain/snow changeover line, though farther inland it will be more of a wind-driven powdery snow.
I think in the end it may fall a little shy of the 1978 storm, but it will be a close rival for most. Regardless, it will bring travel to a standstill in the affected areas later tomorrow into Saturday, before the snow can begin melting early next week.
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.