WINTER STORM SUMMARY FOR
FEBRUARY 12, 2008 TO FEBRUARY 13, 2008 EVENT

Synopsis

On Tuesday morning, February 12, 2008, high pressure extended from James Bay in Canada down to the middle Atlantic coast. Low pressure was developing over the lower Mississippi River Valley. By Tuesday evening, the high had drifted to the northeast, with its axis extending southeastward from central Quebec to the coastal waters of New England. The low had moved to the northeast and into the eastern Ohio River Valley with another low developing over Alabama. 

By daybreak on Wednesday February 13, the first low had moved up over Lake Ontario. Meanwhile, the second low had deepened and it was located over the Carolinas. By midday, the first low had dissipated and the intensifying second low was passing off the coast near the North Carolina and Virginia border. The coastal low continued moving to the northeast, passing over Cape Cod on Wednesday evening.

Watches/Warnings/Advisories

Early on Monday morning, February 11, a Winter Storm Watch was posted for Tuesday afternoon into Wednesday morning. It covered the Poconos, the Lehigh Valley, Berks County and northern New Jersey. On Monday afternoon, the watch was expanded to include the Pennsylvania counties of Chester, Montgomery and Bucks. 

Early on Tuesday morning, the Winter Storm Watch was upgraded to a Winter Storm Warning and the warning was expanded to include the New Jersey counties of Middlesex and Mercer. A Winter Weather Advisory was issued for the Pennsylvania counties of Delaware and Philadelphia; for the New Jersey counties of Monmouth, Ocean, Burlington, Camden, Gloucester and Salem; for New Castle County in Delaware and for the Maryland counties of Cecil and Kent. The advisory was put into effect for Tuesday afternoon and Tuesday evening. 

On Tuesday afternoon, the Pennsylvania counties of Delaware and Philadelphia were upgraded to a Winter Storm Warning. The Winter Weather Advisory was expended to include Queen Anne's County in Maryland, Kent County in Delaware, and the New Jersey Counties of Cumberland, Atlantic and Cape May. The coastal strip of Atlantic County and Cape May County was not included in the advisory. 

On Tuesday afternoon, a Flood Watch was issued for northern Delaware, southeastern Pennsylvania and northern and central New Jersey. The watch was put in effect for late Tuesday night through Wednesday night.

Precipitation/Temperatures/Winds

Light precipitation began to spread up into northeastern Maryland, Delaware, eastern Pennsylvania and New Jersey on Tuesday morning. Initially the precipitation took the form of snow flurries then areas of light snow moved up from the southwest on Tuesday afternoon. 

By Tuesday evening's commute, snow was falling throughout much of eastern Pennsylvania and northern and central New Jersey. Meanwhile, the snow had changed to sleet and freezing rain in extreme southeastern Pennsylvania, in southern New Jersey and on the upper Delmarva Peninsula. Rain was falling in southern Delaware and along the southern New Jersey coast. 

During the course of Tuesday evening, warm air continued to build up from the south. By midnight, temperatures ranged from the middle 20s in the Poconos to the middle 50s in Sussex County, Delaware. At midnight, any snow and sleet in the region had all but ended. Freezing rain was falling throughout much of eastern Pennsylvania and northern New Jersey. Rain was falling in southern New Jersey and on the upper Delmarva Peninsula. 

Snowfall totals on Tuesday ranged from 2 to 4 inches in the Lehigh Valley, the Poconos and northern New Jersey to a half inch or less in the vicinity of Philadelphia. 

On Tuesday evening, ice accumulated from around a tenth of an inch to a quarter of an inch from the upper Delmarva Peninsula and the Philadelphia metropolitan area up into central New Jersey. From Tuesday night into early Wednesday, ice accumulations ranged mainly from a quarter to a half inch in Berks County, the Lehigh Valley, the Poconos and northern New Jersey. 

By Wednesday morning's commute, the freezing rain was confined mainly to the Poconos and to northern New Jersey. Heavy rain had begun to move into the rest of the region. Around daybreak on Wednesday, a frontal boundary extended southwestward from Raritan Bay to the upper part of Delaware Bay to the lower part of Chesapeake Bay. To the west of the front, temperatures were mainly in the 30s and to the east of the front readings were mostly in the 50s. The temperature contrast was quite sharp over a short distance. For example, the 7:00 am temperature at Northeast Philadelphia was 37 degrees while the temperature at Mount Holly was 55. 

By 10:00 am on Wednesday, the freezing rain in the Poconos and in northern New Jersey had changed to rain. Rain continued to fall in the entire region during the balance of Wednesday morning and through much of Wednesday afternoon. The rain became quite heavy at times. 

Liquid equivalent precipitation totals from the entire event ranged mainly from one to three inches in eastern Pennsylvania, New Jersey, Delaware and northeastern Maryland. A few locations in eastern Pennsylvania and in northern New Jersey picked up closer to four inches.

Significant Impacts/Aspects

The snow, sleet and freezing rain resulted in numerous traffic accidents throughout the region on Tuesday evening. Accidents related to the ice caused the closure of a number of major roadways, including sections of Interstate 95 and the Schuylkill Expressway in Philadelphia, the Commodore Barry Bridge, and the Admiral Wilson Boulevard in Camden. 

Ice accumulated on trees and utility wires resulting in numerous power outages in eastern Pennsylvania and in northern New Jersey on Tuesday night and Wednesday. 

The heavy rain made for another difficult commute on Wednesday morning. Problems were complicated in eastern Pennsylvania and in northern and central New Jersey by the lingering ice, slush and snow which blocked storm drains. As a result, water collected on roadways, making some of them impassable. 

The heavy rain caused widespread minor flooding throughout the region on Wednesday with numerous flood warnings being issued by the National Weather Service.

Notes

Information contained in this summary is preliminary. More complete and/or detailed information may be contained in subsequent monthly NOAA storm data publications.