Friday, April 12, 2013

Rainy Start, Warm Front Watching Later

This morning's rains around the region will push through over the next several hours, steady and heavy in some spots.  An inch of rain is possible in some spots as a chilled rain moves on through the Delaware Valley over the course of the morning hours.  Rain will impact the region mostly during the latter half of the morning rush hour as well as into the midday.  A rumble of thunder can't be ruled out either.

Coinciding with all of this is a warm front (yesterday's backdoor front) that will try to lift back north.  Higher resolution modeling does lift the warm front into South Jersey into the afternoon hours and provides a temperature boost to everyone below Route 40.  Some of the more traditional models don't bring that boundary quite as far to the north but do at least bring warmth into Delaware during the afternoon hours.

Winds are gusty this morning but should die down as we work into the midday hours -- they are gusting to over 25 mph in a number of spots but as the rains move on through and we get near the low pressure system itself it should die down a bit later on.


The cold front that ends all of this will push in from the west during the afternoon hours and will bring a risk of thunderstorms in the warm sector, with showers (and perhaps a heavier burst of rain and some gusty wind) north of the warm front.  This front is timed to push through during the mid and late afternoon hours.

The warm front may get to Philadelphia...but it's a close call.  It's going to be tough for it to get much north and northwest of that.  The result will be a cool, damp day to the north of the city where 50ish may be the best we can coax in Allentown, with mid to upper 50's across the Philadelphia suburbs.  We're thinking the city gets to just above 60 but it's possible the northern half of the city falls short of that except for the Airport.  South of the city could get into the 70's and some of the higher resolution modeling suggests mid and upper 70's in parts of Southern Delaware tomorrow afternoon.  We're projecting mid 70's for Dover and points south.   There will be a pretty sharp temperature contrast between Allentown and Dover tomorrow, perhaps on the order of 20 or more degrees.

The good news for everyone...and especially for forecasters...is that Saturday will be a much easier day to forecast!