Milder in the Northeast Tuesday into Wednesday
November 27, 2017; 9:34 AM
1. While there have been some cold outbreaks, no prolonged chill has occurred, and none is imminent. At the 10 mb level, where we look for a breakdown/reversal, split or large displacement of the usual vortex found near the North Pole at that level high in the stratosphere as a cold signal, no such event is taking place now:
There is some displacement from the pole, so we will be looking for any changes in the near term.
2. This map shows today's projected temperature for around 2 p.m. ET today, almost the time for the typical daily high temperature in late November:
3. This pressure analysis shows that a northwesterly flow of cold air is taking over in New England. However, with quick west to east motion continuing aloft, the southerly flow shown west of the Great Lakes is on the way.
Note the 12 degree (Fahrenheit translation) at Sudbury, Ontario. That cold air is headed toward central and northern Maine, where temperatures could drop to the single digits later tonight. At Boston, the low tonight should be near 25.
4. During the holiday weekend, some models showed the development of a big storm near the East Coast for next weekend. Since then, however, most solutions have backed off from that idea. The reason: the troughs aloft that could make that happen seem to be out of sync with one another, with no sign they will join to form a major storm. This sequence of maps shows the progression shown by the GFS ensemble mean 500 mb forecasts for 1 p.m. today, Wednesday and Friday:
Today, troughs A and B have different orientations and are not in sync. Trough a looks like a potent system in its own right, however, so we will see what (supposedly) becomes of it:
On this forecast for Wednesday p.m., trough A is shown to be weakening. Trough C is seems poised to tap into some moisture that would flow in from the Gulf of Mexico.
This forecast for Friday p.m. shows just about the flattest westerly flow we ever get to see. If this is right, any showers with trough C are getting ready to move offshore.
The views expressed are those of the author and not necessarily those of AccuWeather, Inc. or AccuWeather.com