BETHLEHEM, Pa. — The Lehigh Valley could see “a little bit of trouble overnight,” one local forecaster said early Friday.
The area is under a winter weather advisory from 7 p.m. Friday until 9 a.m. Saturday for freezing rain, with total ice accumulations up to one tenth of an inch expected.
“It doesn’t matter what amount it is, it’s still treacherous on area roadways,” EPAWA meteorologist Bobby Martrich said in his latest video update.
The advisory covers a large swath of the region, including Carbon, Monroe, Lehigh and Northampton counties in Pennsylvania.
In New Jersey, Morris, Sussex and Warren counties also are expecting wintry weather.
Timing, setup
“This is going to be after midnight and before 8 a.m. Saturday morning,” Martrich said.
He highlighted the Interstate 78 corridor and points north as locations where freezing rain will be possible thanks to a setup known as cold air damming.
“We have overrunning precipitation, with warm air aloft overriding colder air at the surface where temperatures are below freezing,” Martrich said. “It falls as rain.
"It’s a deep layer of warmth aloft, so that will fall as rain and when it hits the surface, it freezes.”
Martrich said pockets of freezing rain could hang on in the higher elevations of the Poconos until around 5 a.m., and will change to rain pretty much everywhere going into Saturday morning.
“But again I have to stress that any amount of freezing rain, even if it’s only a little bit and only for a couple hours, is treacherous,” he said.
" I have to stress that any amount of freezing rain, even if it’s only a little bit and only for a couple hours, is treacherous."EPAWA meteorologist Bobby Martrich
The National Weather Service warned that nighttime travel could become slippery and hazardous, especially along bridges, overpasses, other untreated roadways and untreated sidewalks.
Warming trend to follow
“The good news is that temperatures will be steadily warming beginning Saturday morning,” the weather service said in its latest forecast discussion.
The bad news is that precipitation over the weekend will be the result of two different systems, with light rain expected Saturday and heavier rain anticipated Sunday.
“As the cold front associated with this (second) system approaches our region Sunday night, not only will the rain expand over the remainder of the region, but (we) could have heavier rain as it does,” the weather service said.
Models also continue to show the chance of a few embedded thunderstorms as well.
Areas that don’t see a dry slot over the weekend could see rain totals of 1 to 2 inches, forecasters said.
