Winter Weather in Maryland, December 14, 2013

A series of low pressure systems combined with a high pressure system passing across nearby Canada to bring a wintry mix of precipitation to northern Cecil County on the 14th. Snowfall averaged less than one inch with a brief period of freezing rain toward the Pennsylvania border before precipitation changed to plain rain. The combination caused some slippery traveling conditions. Snow started by the middle of the afternoon on the 14th and transitioned over to rain south of the Chesapeake and Delaware Canal. The snow briefly changed to sleet and freezing rain and then just plain rain by the start of the evening. Rain continued into the overnight before ending. Representative snowfall in Cecil County included 0.5 inches in Elkton.

The wintry mix was caused by a series of low pressure systems, one emerging from the central Rockies and the second forming in the western Gulf of Mexico on the evening of the 13th. They reached Missouri and Mississippi respectively on the morning of the 14th. Meanwhile, a high pressure system with a fresh supply of cold air reached southern Quebec Province, Canada. While the southern low pressure system weakened, the northern one reached the central Ohio Valley at 4 p.m. EST on the 14th as the center of the high pressure system started to cross the Saint Lawrence River Valley and slowly eased east during the evening and overnight. A new low pressure system was starting to form on the warm frontal boundary in North Carolina. This latter low pressure system started to intensify as the Ohio Valley low pressure system started to weaken. At 10 p.m. EST on the 14th, the former low pressure system reached the lower Chesapeake Bay. This low became the main low pressure system and passed just east of Atlantic City, New Jersey at 1 a.m. EST on the 15th and eastern Long Island at 7 a.m. EST on the 15th. The sequence of secondary formation helped bring in enough warm air at the surface to negate most of the wintry weather in Delaware.