Back To Home
The Story Behind the Weather - By Forecaster John Ensworth M.S. - 

The Discussion of Weather Events Daily for Philadelphia and Pennsylvania

 Last updated: 11/28/2003 03:55 AM
 

Good Morning Philadelphia!   

    I'm glad to announce that these discussions will continue until at least the end of this Year!.  I have the needed server space.

In short:   Cool and dry weather through Turkey Day, then a chance of rain for that night through Friday with a POSSIBILITY of some snow flurries by the end of the precipitation Friday night into Saturday morning.  OOoh, hold on!

The last week of rain has resulted in broad areas of 4" accumulations.  Amazing!  We were in the solid 2-3" amounts around Philadelphia. 

And though there are a lot of clouds around, no organized storminess is threatening today. 

To back that up, look at how quiet the surface map is.  There is a high pressure system sliding off to our east (the core of the cold air that swept across the nation is leaving). 

Since air flows clockwise around a High pressure center, we have returning south winds (with warmer and moister conditions already). 

Still, the remaining chill in the air plus winds are giving us 40's wind chills this morning. 

The weather is quiet on the east coast because we have a quasi-ridge over the east.  There IS a big trough in the center of the US, and we are sort-of on the up hill side of the that trough (where you would expect the storms/rain) but it is so broad that we are not really in the active lift zone (that is located more over the Mississippi Valley this morning). 

So the showers today are confined in a loose band near the developing Low pressure system over Oklahoma and eastward.  Too far away to worry about- yet. 

The surface map by Thanksgiving morning shows the lower Mississippi Valley system gaining some more strength. 

So, for later Thanksgiving day, we'll see a chance of rain entering the state from the west.  With all rain (except in the Great Lakes) we shouldn't see any travel problems through Thursday. 

The upper level winds are buckling in a deeper trough- giving more life to our approaching storm by Thursday evening. 

And at that time, a good band of rain is hitting the lower Ohio Valley and approaching the south.  A warm front is tightening to our south and moviong north. 

On Friday, the band of rain passes and snow showers begin to form to the west behind the leading precipitation. 

The first front leaves with the trough off the east coast, and the shot of snow chances gets organized as the next trough begins to ripple into the Great Lakes to our west. 

So Saturday sees colder temperatures coming in behind the front, and snow falling through the higher elevations of Pennsylvania.  Will we see snow IN Philadelphia?  Probably not, but we'll keep an eye on it here!

An advanced look at your Sunday travel day shows that the 'bad' weather is confined to the upper New England states and IF there are any snowy roads in Pennsylvania, they will be cleared out by now. 

Have a Great Thanksgiving Day and I'll try to be here tomorrow (but if travels and Turkey keep me away, I'll be back Friday!). 

Meteorologist  John Ensworth

Surface Station sky cover color key: