Sunday AM: 7/26/09
A SEVERE THUNDERSTORM THREAT LATER THIS AFTERNOON AND EVENING, FOR THE ENTIRE DELAWARE VALLEY !
A slow moving cold front now stretching from upstate NY, south into Central PA and western VA, will move into the region later today and tonight. This front will stall out near the coast tonight and tomorrow. An Upper level low over the lower great lakes will also slide east. A very warm and unstable air mass ahead of this front, along with some upper level dynamics, will trigger strong to severe thunderstorms this afternoon and evening. These storms will produce very heavy rain, strong gusty winds, and some hail.
A weaker area of showers and thunderstorms will move into Eastern PA and Northern NJ during the mid and late morning hours. So areas North and West of PHL will see some activity before noon.
Some sunshine can be expected early this afternoon but during the late afternoon hours a more intense complex and line of storms will move into the entire Delaware Valley. Some of the heaviest activity will be over SE PA, DE, and Southern NJ with these storms that develop this afternoon and evening.
A general .25" to .50" of rainfall will occur over many areas, however any areas that receive strong to severe storms, could see 1.00" to 2.00" amounts and localized flooding.
A Severe Thunderstorm watch will likely be issued early this afternoon and continue into this evening. I've provided links for 2 Radar loops and a visible Satellite loop below to track these storms. Or go to my radar and satellite section of this site for more loops and information.
Regional Radar Loop
Local Radar Loop: Delaware Valley
Satelitte Loop for M/A Region.