Middle Atlantic and southern New England: Turning warmer
Tuesday, March 22, 2016
1. Southwest winds will carry milder air into the Ohio Valley, southern Great Lakes, the Middle Atlantic states and southern New England today into tomorrow.
2. Once the warmer air comes into the Ohio Valley and Middle Atlantic areas, it will stay until a cold front arrives Thursday night or Friday.
2a. Note according to the AP, New York is one of the Middle Atlantic states. However, the climate of central and northern New York is often most similar to that of central and northern New England. In this case, any incursion of milder air into those more northern areas is likely to be quite temporary, and it will be chilly Wednesday night and Thursday.
3. As a storm center moves from Kansas to Illinois between tomorrow and Thursday, very mild air will be displaced by wintry blusters and a changeover from rain to snow from Nebraska across northern Iowa, southern Minnesota and then Wisconsin. In the heart of the snow area, wind-whipped snow will create blizzard conditions.
4. As the storm center moves through the Great Lakes region over to upstate New York and New England between Thursday and Friday, there will be cold rain north of the track and a surge of warmth to the south. However, a cold front extending south from the storm center will produce thunderstorms, some severe, then bring chilly air eastward behind it.
5. Beyond Friday, there is increased uncertainty because the two main computer models are almost one whole day out of sync (example, the U.S. has the storm centered in Maine on Friday while the Euro model has it near Buffalo. This makes a huge difference in timing warmth and chill, precipitation and dryness.
This video has more:
From time to time, I have shown you maps for the flow at the 10 mb level high in the stratosphere. One signal for major cold outbreaks in winter is when a vortex at the pole at 10 mb breaks down or reverse to a high pressure area. When that kind of reversal happens at the end of March, there much less reason to believe a cold wave is coming. But perhaps it means the steam roller to spring gets delayed and periodic episodes of cold will occur. These maps show the vortex disappearing and getting replaced by a high between Feb. 20 and yesterday.
A month ago
Now
