Wednesday 9 a.m.
Cool air from New York City northeastward should retreat today and tonight to allow a summery air mass to take over. Strong thunderstorms developed yesterday from New York state into central New England, and that can happen again today. There is an enhanced risk of severe thunderstorms, which can include damaging winds and large hail all the way from that region southwest through most of Pennsylvania, West Virginia, Ohio, Kentucky and parts of Tennessee, eastern Indiana and northern New Jersey. Please realize that since this story is not updated later, you can check out the severe weather info elsewhere on AccuWeather.com
A cold front now in the Midwest will cross the Eastern states tomorrow and will be offshore Friday. Very chilly air for this time of year will pour south behind to get the holiday weekend off to a chilly start. If your plans include camping in the mountains between West Virginia and New Hampshire, prepare for nights as cold as the 30s, and the highest elevations could even get some snow!
This computer model map for 8 a.m. EDT Sunday shows the upper airflow over the Northeast coming directly from Hudson Bay. This explains why it will be so chilly, at least the first half of the Memorial Day weekend.
This map shows where Hurricane Joaquin was just before 8 a.m. ET. You can also see the stripe of clouds centered just of the Middle and North Atlantic coasts.
There are competing forces acting on it, and each move it makes will place it under different influences. This has made it very difficult for computer models and meteorologists to judge where it will actually go. This is reflected in the track model collection on this map:
In assessing the final impact of the storm system coming into the East, there are three main components. First is the cold front coming across the Appalachians tonight in a very rich moisture field with ...
On this map, the cold front that will eventually move through the Northeast is in the far northwest corner of the picture. There are areas of showers moving northeastward well ahead of the front, but the steadiest rain is not likely until the cool air moves in and the front stalls.
The Midwest and Northeast are in the latitude zone where winds are primarily from the west. The direct opposite is the case today, as seen on this pressure analysis. The easterly flow brings in moisture from the Atlantic.
The infrared satellite picture below shows the cloudiness as of midmorning on Thursday. If it stays the way it is now, there is no problem in the Northeast. However, on another screen I have been watching the whole area expanding north and west, as indicated on the map.