Halloween weather: Scary skies, but rain looks to hold off during dry trick-or treat hours. ‘Squall line’ due later
The nasty weather should hold off until late Thursday night; trick-or-treat time could be mostly dry and springlike.
The skies are appropriately spooky, and forecasters warn that potent storms late at night could leave some people in the dark. A tornado watch has been posted as nearby as Lancaster County.
But fortuitously it appears that the lull in the rain is going to last through the peak trick-or-treat hours around Philadelphia.
The National Weather Service has precipitation probabilities falling to zero at 8 p.m. then shooting back up late Thursday night.
“It looks like it’s trending drier,” said Mike Silva, a lead meteorologist at the weather service office in Mount Holly.
The skies will maintain the haunted look, and witches hold on to those brooms: Winds could gust past 25 mph.
A strong low pressure system is forecast to lift toward the Great Lakes, and since the region will be on the warm side of the storm, temperatures will hover around 70 during trick-or-treat time. It also will be humid.
The clouds will have a plus side, the weather service says, in that they will mute solar heating that could ignite thunderstorms during the day, and the upper air isn’t favorable for them.
The rain is not expected to return until a powerful cold front approaches late Thursday night. “We’re definitely expecting a narrow but fairly intense squall line,” Silva said.
The National Weather Service Office in Mount Holly warns that gusts to 60 mph could accompany the front, especially given that trees in the region remain mostly leaf-filled. Leaves add weight to branches and and also tend to intercept wind.
“Be prepared for damaging wind gusts Thursday night with the line of heavy showers,” the weather service said.
Just over a half inch of has fallen officially in Philadelphia, pushing the total for October close to 3.7 inches — triple what fell in a parched September.
Temperatures for the month have averaged 3.4 degrees Fahrenheit above normal at Philadelphia International Airport.
This will mark the 10th-straight October of above-normal temperatures in Philadelphia.
But Saturday morning could bring the lowest temperatures in over six months, and come Monday morning, Philadelphia officially could experience its first freezing reading of the season.