A Warm Wednesday
A warm night will lead to an even warmer day. Temperatures starting out in the upper 50's and low 60's in Philadelphia (with mid to upper 50's in the countryside) will warm quickly with sunshine becoming filtered through increasing high clouds in the afternoon in advance of a frontal boundary. We're looking at high temperatures generally in the low and mid 80's across the region, which is about 10-15 degrees above normal and surprisingly close to record high temperatures for this date. Record highs range from 85 at Trenton to 88 at Philadelphia and Wilmington. I don't see any records falling but nonetheless, it should be a very warm day in the area.
Tonight, the front passes through and showers, along with a few thunderstorms, will accompany the front. The Storm Prediction Center has Central and Western PA in a Slight Risk of Severe Weather for today and I do believe that any severe that develops should stay west of Philadelphia because there will be a lack of daytime heating to support these storms as they move in at night. Rainfall amounts should be pretty light overnight -- about 1/4" of rain.
Low temperatures tonight should stay warmer than normal, with readings at or above 60 from Philadelphia and points east as the front crosses from west to east. Temperatures won't rise much on Thursday as a northeast wind takes over on the backside of the front. It will be much cooler and this cooler pattern will take over for the next few days. High temps on Thursday will be in the 60's regionwide, with lows overnight Thursday getting down to 40 in the Lehigh Valley and staying near 50 in Delaware and South Jersey due to cloud cover.
This cloud cover will be from an area of low pressure that will develop along the front as the front stalls to our south over the Delmarva. The low will be a slow-mover and lead to a persistent northeast wind flow off of the Atlantic for Friday, Saturday, and Sunday. For South Jersey and Delaware, Friday-Sunday will be ugly days with clouds, off and on rain, and a stiff breeze at the coast. Friday, right now, looks to be the best of those three days for Philadelphia in terms of the amount of sunshine possible. The weekend looks to be mostly cloudy and perhaps damp at times in Philadelphia. As one moves north and west, things will improve steadily in terms of shower chances and cloud cover with a pretty nice weekend in store for the Lehigh Valley and Berks regions. I'll have more on this in the coming days but right now, for about half of the region, this weekend may not be so nice.
