Winter Weather in Pennsylvania, February 14, 1997

A high pressure system brought in a relatively cold and dry air mass into the Northeast on the 12th and 13th. Then a low pressure system travelled along the Eastern Seaboard and dropped a wintry mix of snow and freezing rain across Southeast Pennsylvania through dawn on the 14th. Precipitation started as snow throughout Southeast Pennsylvania the night of the 13th/morning of the 14th. South winds above the ground brought in relatively warmer air and changed the snow to freezing rain between 4 and 7 a.m. EST. East winds near the surface then brought in warmer air and helped change the freezing rain to just plain rain during the morning commute. As is typically the case, the change to plain rain took the longest across Berks County and upper parts of Bucks and Montgomery Counties. Accumulations prior to the change over averaged 2 to 4 inches in Berks County and 1 to 2 inches elsewhere. Driving on untreated roadways was very hazardous. Snowfall totals included 4 inches in Reading, 2.4 inches in Springtown, 1.8 inches in Glenmoore, one inch in Southampton and Honey Brook and 0.7 inches at the Philadelphia International Airport.The low pressure system responsible for the wintry mix developed over northern Mexico on the 12th. It moved along southern parts of the Gulf Coast States on the 13th before moving quickly up the Eastern Seaboard the night of the 13th through the night of the 14th. The low went from Savannah, Georgia at 7 p.m EST on the 13th to Portland, Maine at 7 p.m. EST on the 14th. The fast movement kept precipitation totals down. Conversely since it was a relatively weak low pressure system, the winds were light and this kept cold air trapped in the valleys and prolonged the changeover to plain rain.