The entire Philly region is facing a flood watch into early Tuesday, with a small chance of a tornado
Some storms could be severe, and the government's storm center lists a 5% chance of a tornado.
With the atmosphere ultra-juiced with water vapor and conditions aligning favorably for downpours, the National Weather Service has issued a flash-flood watch for the entire region in effect until 6 a.m. Tuesday.
Rains could fall at the rate of 1 to 2 inches an hour, and that could cause some of the region’s flashier creeks to jump their banks and road-pond in urbanized areas, said Cameron Wunderlin, a meteorologist at the National Weather Service Office in Mount Holly.
Higher amounts are possible if thunderstorms develop and “train” — that is, keep targeting the same areas. The frontal boundary igniting the storms is slow-moving, and the atmosphere is primed.
“It’s definitely a training situation,” Wunderlin said.
The government’s Storm Prediction Center had the region under a 15% chance of severe thunderstorms, those with winds approaching 60 mph, and a 5% chance of a tornado.
The heaviest storms are expected between 11 p.m. and 3 a.m., the weather service says.
Rainfall this month has been from 130% to 160% above normal in Philadelphia and its neighboring counties, according to the Middle Atlantic River Forecast Center, in State College.
Evidently, those percentages are about to increase.