Temperatures are expected to fall below freezing for several hours tonight from the suburbs of Philadelphia through the Shenandoah Valley of Virginia.
This would result in a killing freeze and mark the end of the growing season for these areas. Since a freeze has already occurred over much of Pennsylvania, it isn't as big of a problem farther north as it is for points south.
A large zone of high pressure is building into the region from the north, keeping a chilly air mass in place from the northern Plains through the Northeast.
Clouds are currently persisting over a good portion of the mid-Atlantic thanks to the cool air aloft and if these clouds break as expected tonight, then temperatures will plummet.
Low temperatures are expected to be near 34 in downtown Philadelphia with many of the suburbs falling to between 29 and 32 degrees.
Farther south, temperatures from Washington, D.C., to downtown Baltimore will end up between 34 and 36 overnight, but many suburbs will also experience that killing freeze.
Even for some metro areas from Dover, Del,. to inland areas of southern New Jersey, temperatures are expected to plummet to near or below the freezing mark.
This is bad news for residents still without power after Hurricane Sandy.
Freezing temperatures are also expected to end the growing season for much of the Shenandoah Valley of Virginia from Leesburg through Fredericksburg, Staunton, Charlottesville and Lynchburg. Residents of these cities and other locations mentioned above should protect any plants from this freeze by moving them indoors and bring pets inside for the overnight hours.
For more information on the freeze watches and warnings in effect, please visit the AccuWeather.com Severe Weather Center.
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