After the heaviest rains in months put a significant damper on one of the driest periods in the last several years, a possible record-setting storm that became a meteorological “bomb” is forecast to continue lashing the region with a daylong siege of potent winds Thursday, with gusts up to 50 mph.
The National Weather Service has a wind advisory in effect until 6 p.m. Peco reported about 30,000 outages Wednesday night into Thursday, and the weather service has advised residents to secure loose outdoor objects.
The storm, which was spinning over New Hampshire Thursday morning, met the technical criterion to be classified as a “bomb” — a rapidly deepening cyclone — said Paul Walker, senior meteorologist at AccuWeather Inc., adding that it might have set a record for October intensity for a storm so far north.
Rounds of heavy rains continued into Wednesday evening, with higher amounts to the north and east of Philadelphia.
Officially, 1.14 inches was measured at Philadelphia International Airport, the most on any day since Aug. 7. But the NWS in Mount Holly recorded a storm total rainfall of 2.26 inches, making it the largest single event total since June.
Flooding was reported on Route 130 at Collingswood and in Atlantic City, the agency said, and winds took down a tree that closed Route 9 near Mays Landing Road.
For homebound commuters Wednesday, the timing of the heaviest rains was unfortunate. Officially, Philadelphia was doused with 0.7 inches in between 3 and 5 p.m.; that exceeded the total rainfall from Sept. 16 through Tuesday.
Wet leaves can be especially hazardous on roads, and SEPTA has long struggled with slippery rails on its Regional Rail system. In addition, rain-ferried leaves tend to clog storm drains, leading to road ponding and flooding.
But if this was a practice run for the inevitable snow and ice of winter, it evidently was a decent one. “So far so good,” said SEPTA spokesperson Andrew Busch. “We’re keeping an eye on it.”
SEPTA reported only routine delays, save for the Trenton line, but the problems resulted from an accident involving a truck that hit a railroad bridge. It was not clear whether that accident or any others were storm-related.
And while the rains were the most robust in Philadelphia in more than two months, widespread flooding was never a threat, thanks to the recent dryness.
A substantial portion of the East "has been exceedingly dry over the last month,” said Brad Rippey, a meteorologist with the U.S. Department of Agriculture, “but the area from D.C. to Philly has a pretty strong dry signal going back to mid-July.”
Through Tuesday, rainfall amounts in the last 30 days generally have been a quarter to a third of normal in the Philadelphia region. In the city, less than an inch had fallen, according to the Middle Atlantic River Forecast Center, or 17 percent of average.
In New Jersey, September was drier than any other month since September 2007, said David Robinson, a Rutgers University professor who is the state climatologist. In Philadelphia it was the driest month since March 2012.
The next concern will be the duration of the storm-related strong winds, said Joe Miketta, the warning coordination meteorologist in Mount Holly. At least scattered power outages are possible.
But all that preceding dryness may offer another benefit. The trees should be well-anchored and less likely to topple into wires, although the winds are expected to put up a fight.
As it moved north toward New England, the storm had been forecast to approach “bomb" status — a technical distinction based on how rapidly it intensifies. It was not clear Thursday whether it had acquired that distinction, but the gusts reported in New England have been hurricane level.
Winds circulate counterclockwise around centers of low pressure, so areas south of the center experience winds from the west.
That could work to the Shore’s advantage. Winds from the west will be blowing offshore rather than onshore, where it could stir up beach-eroding waves.
If anything, Robinson said, that could lead to the opposite of coastal flooding — a blowout tide.
The next few days should be dry, and chilly. Temperatures early Saturday could fall into the low 40s, where they haven’t been since April. And then the pattern might get friskier, said Trent Davis, a weather service meteorologist in Mount Holly.