Tuesday 9:45 a.m.
A southwesterly flow of warm, moist air ahead of a cold front is contributing to a band of rain and thunderstorms that stretches from the Ohio Valley into parts of the Middle and North Atlantic states. We expect some showers and thunderstorms to cross the I95 corridor from D.C. to Boston later today and this evening.
The cold front should slip south then stall from Virginia or Maryland to Kentucky tomorrow. With the front likely to make only limited progress, some additional showers may occur tomorrow from D.C. to New York City and on west. Most of New England should turn sunny.
In general, computer models suggest a low pressure area forms along the front in the Middle Atlantic states on Friday then slowly moves up along the coast this weekend. If that happens, it will be a damp weekend in the I95 corridor of the Northeast.
In contrast, most of the Great Lakes region looks like it will bask in sunshine with afternoon temperatures in Detroit and Chicago close to 70 and nights cooling to the 40s and 50s. The video has more.
In the longer range, the re-curving of the latest western Pacific typhoon may signal an upper air trough (and cool weather) in the Northeast in a week to 10 days.
Late September is not generally known for widespread thunderstorms, but this map shows near 50,000 lightning strokes in the period from 8 EDT last night until just after 8:30 EDT this morning.
in response to the approach of a deepening trough from the Plains, a Midwest low pressure area will grow stronger as it moves east to arrive on the New England coast Saturday morning.
In the I-95 corridor from D.C. to NYC, temperatures will be up past 80 this afternoon. However, between now and Saturday, a major change is on he way.
In eastern New England, an onshore flow of cool damp air prevailed all morning. There could be a last-minute warmup this afternoon. The affected areas will certainly be warmer tomrrow morning than they were this morning.
Now, out-of-season warmth is set to be the rule through midweek from the Ohio Valley to much of New England. Peak leaf color in Pennsylvania and New Jersey ranges from now northern mountains) to Halloween (in parts of South Jersey).
The Pacific storm caused some strong thunderstorms in northwest Oregon yesterday, bringing an end to a very long hiatus in the need for tornado warnings there. Note also the lack of tornadoes in eastern Tennessee.
Although the storm is not headed toward the US mainland, 6 to 8 foot waves are found not too far offshore from the Carolinas.