PHILADELPHIA (KYW Newsradio) — With the first major snowfall of winter expected in the Delaware Valley to arrive in the next 24 hours, the National Weather Service has issued a winter weather advisory on Monday for Philadelphia, Delaware, Burlington, Camden and Gloucester counties along with the Wilmington area in Delaware from 4 a.m. until 4 p.m.
A winter storm warning has also been issued for numerous Jersey shore counties and central and southern Delaware.
"Quickly changing forecast," said NBC10 First Alert Meteorologist Steve Sosna.
"Snow will develop after about 2 a.m., first across South Jersey and Delaware, and even up to Philadelphia by about 3 a.m. or 4 a.m."
Snow totals were expected to vary, depending upon where the storm tracks, with the largest accumulations expected to come south of Philadelphia in New Jersey.
"If you live across South Jersey into Delaware and down toward the shore," Sosna said, "we're looking at 6 or more inches at the shore. We are looking at 3 to 6 inches across South Jersey, anterior South Jersey, and into Delaware. In Philadelphia itself, about 1 to 3 inches right now."
But as Sosna said, the forecast has been quickly changing.
Before the snow comes, a major cooldown was expected to bring temperatures to winter coat-wearing levels after 60s earlier Sunday afternoon.
"We're out ahead of a powerful cold front. That will bring us a couple of scattered showers," said Sosna.
"The wind (will reach) 40 miles per hour and the temperatures are going to start to fall, especially after about 5 p.m. or 6 p.m. down into the 40s and then we're into the 30s overnight tonight."
