Strong storms are possible in the Philly region into this evening

After a month-long dry spell, the atmosphere has undergone a radical moistening and forecasters say more showers are likely into Thursday evening, with an outside shot at severe storms.

The timing may affect the scheduled Phillies-Miami Marlins game at Citizens Bank Park, on the night after the atmosphere may have given the Phillies’ record home-run barrage a lift.

NOAA’s Storm Prediction Center has posted a “marginal” risk for severe storms — those with gusts approaching 60 mph — for the region.

While the National Weather Service in Mount Holly warned that “a brief tornado cannot be ruled out,” widespread severe weather wasn’t expected, said weather service meteorologist Patrick O’Hara.

Said John Feerick, senior meteorologist with AccuWeather Inc., “I think the greatest concern is going to be for downpours.”

By 4 p.m., a line of strong storms had approached the Lancaster area, where a severe-thunderstorm warning was in effect. The shower threat in the Philly region was likely to persist through the evening hours, the wether service said.

More shower chances are in the forecasts through Monday, and it remains unclear whether any moisture from the tropical mischief brewing in the Atlantic will find its way around here.

Rainfall in Philadelphia and its neighboring counties in Pennsylvania has been about 40% of normal since the dry spell that began Aug. 22, and about half of normal in South Jersey.

In its Thursday update, the inter-agency U.S. Drought Monitor had parts of Philly, all of Delaware County, and most of Camden County in its “abnormally dry” zone.

But the atmosphere began clouding up the windows on Wednesday, and as of Thursday morning about a quarter-inch of rain had been measured at Philadelphia International Airport.

It is unclear what effects beyond rip currents the newly knighted Tropical Storm Humberto and another incipient storm to its east may have eventually on the East Coast.

Humberto is forecast to become a major hurricane and stay well off the coast. The fate of the second system, which is likely to become a tropical storm by the end of the week, is more uncertain.

Models have it moving toward the Carolina coast, said Feerick, but the fact that the two storms are so close together has compounded track forecasts, the National Hurricane Center says.

In the meantime, dampness is due to continue in the Philly region, although the weekend won’t be a complete washout, O’Hara said.

The Phillies may have received a lift from the atmosphere Wednesday night when the team’s eight homers set a one-game record for the franchise, which was born in 1883.

Paul Dorian, a meteorologist with Arcfield Weather, who publishes a “Home Run Factor” index assessing how park and atmospheric factors may affect ball flight, said conditions Wednesday night ranked an eight on his 1-to-10 scale.

Moist air is more buoyant than dry air.

It didn’t seem to help the Marlins.