A slow-moving storm system loaded with heavy rain, lightning and hail crossed Delaware County, Pennsylvania, on Thursday afternoon, November 12, flooding intersections, stranding vehicles in quickly rising water and leaving some suburban streets buried under hail so deep that road crews had to clear it with a backhoe.
Source: Delaware County Daily Times reporting, via Media PA Now
The storm entered the county from the west at about 2 p.m. and crawled across it. Dispatches for fire stations ramped up after 2:30 p.m. and then subsided along with the water after 3 p.m. A National Weather Service tornado watch covering the county was set to run until 7 p.m. but was canceled for the county by 4 p.m., while a flash flood warning remained in effect until 6:45 p.m.
Hail piled up like snow in Parkside and Brookhaven
In Parkside, hail blocked Edgmont Avenue between Upland and Forrestview, and police closed that stretch of road. Parkside Officer Doug Staffelbach said police posted a photo on social media showing a pickup truck stuck in hail that at first glance looked like snowfall, and that PennDOT worked to get the road reopened. He said there were no other issues in the community.
In neighbouring Brookhaven, Police Chief Timothy Habich said the borough experienced significant side-street flooding because storm drains became clogged with leaves and hail. “Police personnel and highway department personnel were very busy getting the drains cleared,” Habich said.
Habich said the borough's highway department was forced to move large amounts of hail from the roadway with a backhoe, and that the hail was several feet deep at Trimble Boulevard and Swiftwater Lane. Some buses were delayed arriving at The Christian Academy because of flooding outside the school's main entrance, he said.
The storm's lightning also struck a tree on the wooded property of the Brookhaven Swim Club. The tree caught fire after the strike, and the Brookhaven Fire Department responded to evaluate it, Habich said.
Water rescues across the western half of the county
The main problems across the county were vehicles stranded in quickly rising water and stuck on hail, with many of the rescues taking place in the western half of the county. Emergency radio traffic indicated there were no injuries. Other spots around the county were also closed for a time while hail melted or was cleared away.
A watch that covered more than 10 million people
Delaware County, Pennsylvania — a suburban Philadelphia county, not the state of Delaware — sat inside Tornado Watch 705, issued by the National Weather Service's Storm Prediction Center at 12:50 p.m. Thursday. The watch covered 20 counties across Pennsylvania, New Jersey and Delaware, an area the Center put at 10,380,513 people, 2,517 schools and 180 hospitals, with a few tornadoes possible, scattered hail up to ping-pong size — about an inch and a half — and isolated wind gusts to 70 mph. The region was in a Level 2 of 5, slight-risk area for severe storms.
Source: National Weather Service Storm Prediction Center figures, via TML News
Rainfall measured at 4:30 p.m. through the MesoWest collaborative showed an Upper Chichester spotter at 0.95 inch and Swarthmore at 0.92 inch, with several other spots far lower — a sign of how uneven the slow-moving storm's downpours were from one neighbourhood to the next.
What happens next
The weather service expected rain at times overnight Thursday, with temperatures diving to the low 40s by daybreak Friday, then rain continuing at times on Friday with a high in the mid-to-upper 40s as a cold front nears. The front was expected to cross the region late Friday into Saturday morning, bringing a blustery, cold day with clearing skies, before conditions moderate starting Sunday, with forecast highs climbing through the 50s to 60 degrees on Wednesday under sunny skies. For residents, the immediate work is cleanup: clearing drains, checking flooded basements and watching for leftover hail and standing water on side streets.