Winter Storm and Winter Weather in New Jersey, December 11 to 12, 2002

A winter storm of sleet and freezing rain affected northwestern New Jersey, affecting Sussex County the most. Precipitation changed to snow before it ended in the county during the night of 11th. A couple of inches of snow accumulated on top of the ice. A shorter duration event of sleet and freezing rain affected sections of Mercer, Hunterdon and Somerset Counties. While it was warm enough aloft for precipitation to fall as rain, enough cold air was left at or near the surface by a departing high pressure system for the rain to freeze on contact or for precipitation to fall as sleet. Precipitation (in the form of sleet and freezing rain) spread from south to north across the area between 8 a.m. and 10 a.m. EST. In sheltered sections of Mercer, Hunterdon and Somerset Counties, surface temperatures remained below freezing throughout the morning and up to two-tenths of an inch of ice accrued to exposed surfaces. The change to plain rain took longer (into the middle of the afternoon) across Warren and Morris Counties. The changeover was also elevation dependent. Higher terrain locations took longer to change to plain rain. In Sussex County, some valley locations changed to plain rain during the afternoon, otherwise a wintry mix continued. Ice accretions in Warren and Morris Counties averaged around one quarter of an inch, highest toward Sussex County. In Sussex County, ice accretions averaged between one quarter and one half of an inch. A couple of inches of snow then accumulated across higher terrain locations during the night of the 11th. Precipitation ended overnight on the 11th. In Sussex County, schools were closed. Dozens of businesses, offices and town halls closed early. Parts of Sparta Township lost power on Springbrook Trail west of Sparta Lake after a tree fell down. New Jersey State Route 94 in Vernon Township was closed near the New York border for several hours after a vehicle rolled over and leveled a utility pole. Less traveled roadways, untreated walkways, parking lots and driveways were very hazardous. Numerous accidents were reported throughout the county. A satellite dish repairman had to be rescued from a roof in Lafayette Township after it iced over while he was working on the dish. Many night meetings and social functions were cancelled. In Morris County, numerous schools in the western part of the county were closed. Several others closed during the middle of the day as did some municipal offices in the western part of the county. Precarious driving conditions were reported in Jefferson and Mount Arlington. In Boonton Township, two accidents within 20 minutes tore down utility poles. Similar conditions were reported in Warren County as many schools dismissed their children early and businesses closed and night meetings (including a Freeholders) were cancelled. A large high pressure system from central Canada brought in cold, dry air into the region. As a low pressure system formed in the Gulf of Mexico on the 10th, it started to push moisture north into the region. As the high retreated into New England, the low moved northeast along the Atlantic Seaboard from near Myrtle Beach the morning of the 11th to near Cape Cod the morning of the 12th. Enough warm air moved westward from the Atlantic to change precipitation to plain rain along the coastal plain. But, the cold air became entrenched, especially over Sussex, Warren and Morris Counties and was difficult to displace throughout this event.