Tuesday, September 18, 2012

Tornado Watch Extended Until 9 In NJ

While no official tornado warnings have been issued in our region, the threat for them does exist if you are to the east of the squall line.  That threat is low but with wind shear in the atmosphere and the threat for strong, damaging wind with the squall line as it moves east.  The tornado watch that was out until 7 PM for the region has been extended for Delaware's southern two counties and for New Jersey until 9 PM.

As we approach 7 PM, the line is from Trenton to west of Vineland, moving east with storm cells lifting northeast along the line.  Winds could gust as high as 60 miles per hour with the line as it moves through and rain will be heavy to intense.  In fact, winds gusted to 44 mph in Philadelphia during the 5 PM line with the storm as it moved through.

Behind the line, rain tapers off gradually but the line itself continues to push northeast.  There is a secondary wave of energy along the front that will enhance the rain for a time post-front later this evening, which means that rains will be slower to taper off across South Jersey, Delaware, and perhaps into the Philadelphia metro.  Farther west, a trough pushing in from the west will bring a round of showers later tonight as well but those will be brief in duration and light to moderate in intensity...nothing like what's fallen today.

Yes, rainfall to our north and northwest was by far a larger story as orographic (terrain) enhancement became the big story in the Poconos.  Eight inches of rain had fallen through 4 PM in parts of Carbon County, with three to six inch amounts common in the Poconos as south winds pushed moisture into the Poconos, squeezing out prolific rains over the higher terrain.

More:  Current Weather Page