Thursday, November 21, 2013

Notable Shot Of Winter Chill Ahead

It's looking pretty likely that the region will have its coolest night since February on Sunday night as temperatures drop down into the lower half of the 20's in the city. Some of the more aggressive modeling out there suggests teens in the outlying areas outside of the city.

Temperatures are just one story in this forecast -- adding a solid ten to twenty mile per hour wind to the equation and the result will be wind chill factors that are solidly in the single digits or low teens on Monday morning in the Delaware Valley.

This upcoming shot of chill is arguably a bit more "arctic" in nature than the hyped one of last week. Given low temperatures will likely be over ten degrees below average and highs on Sunday won't get much above freezing, it's pretty clear we're getting some rather chilled air into the region.

In the wake of that is a storm system that is modeled to move up the coast in the Tuesday night to Thanksgiving morning timeframe, depending on model. Timing and detail are still to be worked out but precipitation type for now looks like rain as the chill shot retreats in just enough time to allow temperatures to be mild enough for liquid for us in the city, suburbs, and points southeast.  The Poconos have a shot at snow but precipitation would need to get that far northwest for it to occur -- modeling right now varies in how far northwest it gets. Last night's run of the GFS, for instance, keeps precipitation away from the region altogether. Past runs have brought rain here and snow northwest of us. The Euro supports rain for us, snow and rain in the Poconos, but temperatures would be too mild for snow in the Delaware Valley.

We'll keep an eye on the modeling with this storm system next week. Even if it is rain that falls, the timing sucks because of Thanksgiving and travel will be impacted along the East Coast. This does not look like a particularly robust storm system on the models but the possibility of travel impacts do exist.