Friday, January 27, 2012

Temperatures' Gonna Jump Up, Jump Up, And Get Down

If you're not a fan of 60 degree weather in January, today will bring a proverbial "House of Pain" to your dreams of snow as we'll get a few hours of fleeting warmth ahead of a cold front (at least in Philadelphia).  It's eventually going to move in -- temperatures are near 60 in Virginia and Southern Delaware, 50's as close to us as Millville and Lancaster.  We'll see that temperature bounce take place probably by 8 or 9 AM at the Airport, with temperatures bouncing to near 60 by late this morning and eventually topping out around 62 at the Airport.

High temperatures will vary quite a bit by location.  The Lehigh Valley may stay in the 40's today, with 50's common south of Quakertown and Reading.  I think the 60+ air hangs out generally east and south of 202 as a general boundary in the Philadelphia metro, with most of South Jersey getting to near or just above 60 degrees as well although the Shore may hang in the upper 50's for a time thanks to the effect of the ocean.  Weird I'm saying that in January.   Regardless, it will warm up for a time later this morning although the extent of how warm may vary a bit -- I do think the Airport will hit 60 for a couple of hours.

Showers and even a few rumbles of thunder are out to the west of the city and are generally moving east and northeast this morning.   The first batch that's nearby at 5 AM will continue to lift northeast, with a second batch out west of Harrisburg which trails down south into Virginia that will push through between 9 AM and Noon  for the city and west, with South Jersey and Delaware getting in on the steadier showers after 11 AM.   As the morning progresses and warmer air pushes north, southerly breezes will increase to between 15 and 20 mph and the fog in place to the north of the warm front boundary will lift quickly as the milder surface air mixes in.    As stated earlier, the warm front should cross through the Philly metro over the next few hours although it may struggle to get much north of the 202 corridor (which is why the outer north/west suburbs will probably only get to the 50's later as opposed to 60).

The cold front that will put an end of the March-like temperature madness is still out in Western Pennsylvania.  That will cross through towards midday and in the early afternoon, putting an end to the warmth while temperatures begin a slow descent this afternoon.  With the frontal boundary passing through, a shot of steadier/heavier rain and wind is possible, especially from the city on south.  The Storm Prediction Center has Lower Delaware under a slight risk for severe "thunder"storms, which may ultimately be more a squall line of thunder-less wind and rain.  

By evening, everyone north/west of the city should be back into the 40's, with low 50's still common in South Jersey and Delaware.  Winds shift to the west and become a bit gustier (35 mph wind gusts are going to be common this afternoon) as we have a gradual return to more typical January weather.