A storm that in some places in the region dumped more than two inches of rain in less than half an hour Friday afternoon was an intensity seen only once every 50 to 100 years. Luckily, the heaviest rain didn’t last very long, but there was enough of it to cause flooding from Chester County through Atlantic and Cape May Counties, said Sarah Johnson, a meteorologist with the National Weather Service.
The most impressive numbers were recorded at the Millville Executive Airport in Cumberland County, N.J., one of the few places with an automated rain gauge. It measured 2.16 inches of rain in 28 minutes. That much rain might also have fallen elsewhere, Johnson said.
Gary Szatkowski, who used to run the weather service office in Mount Holly, had estimated Friday that the rate of rain was “a one-in-200-year event.” On Saturday, however, Johnson said the area could see that much rain that fast every 50 to 100 years.
By Saturday, some rivers were running higher than usual, but none was above flood stage.
Friday’s bad weather started moving through Chester County with a combination of showers and thunderstorms. It reached Cumberland County in late afternoon and caused flooding in Sea Isle City at 6:20 p.m. Along its path, there were reports of wind damage, downed trees, and swamped vehicles. Flooding was reported in New Castle, Cumberland, and Cape May Counties.
During the full storm, 2.92 inches of rain fell in Millville.
Johnson pointed out the area had another storm Thursday. South Jersey was hard hit over the three-day period, but parts of central Pennsylvania got the worst of it, with four to five inches of rain. That area included Union, Snyder, Northumberland, and Schuylkill Counties. The Schuylkill was briefly above flood stage at Landingville, she said.
Our next chance of rain is on Monday.