Monday, November 28, 2011

Round of Rain Tomorrow Ends Warmth

The tranquility of weather in the last few days is about to end as a storm system to our west and southwest pushes through tomorrow afternoon and evening, spreading rain through the region and also putting an end to our mild stretch of Fall weather.   Cooler reality awaits in the wake of the storm system -- although it will not be a full blown onslaught of winter, it will be a step down in temperatures for the latter half of the week and more "typical" late November weather.

We may see a few showers around tomorrow morning in advance of the frontal boundary and the band of rain associated with it, but computer modeling projects the majority of the rains tomorrow will come from the frontal boundary itself -- generally in the afternoon and evening hours as it pushes northeast through the region.  The timing element for the "main brunt of rain" centers around the dinner hour in Philadelphia -- a few hours earlier to our south and a few hours later to our north.   Some modeling is a bit later in timing or a bit earlier but the general consensus for rain starting is in the afternoon, steadiest around dinner, and tapering off around or just after Midnight in Philadelphia.

Rainfall amounts don't look terribly impressive -- generally between a half inch and an inch depending on model run and location as the models shift around where the highest rainfall totals will line up.  The consensus is that more rain falls west of the city than to the city's east but rainfall totals should not be on the order of what we picked up last week from our last storm system.  As a result, flooding really shouldn't be an issue with this storm but it will do a good job of keeping the ground wet.

Some instability remnant showers (or even flurries in Central through Northeast PA) are possible on Wednesday in the backside of this storm system as upper level energy pivots through Pennsylvania.  Cooler air works in as well -- highs will be back in the 50's instead of the 60's as we return to "typical" late November weather.