Furious storms may strike tonight, routing heat

The atmosphere has been in Fourth of July mode, and evidently it's primed to put on a fireworks show.

Strong storms are likely after dark as a potent front tries to rout the first hot spell of the season. Fortunately, after a nightmare afternoon on the Schuylkill Expressway and its tributaries because of a truck accident, it appears the rain will hold off until after the evening commute.

When it comes, it could do so furiously, and the National Weather Service has placed part of the region under a flash-flood watch until late tonight. An inch or two of rain could fall within an hour somewhere between Wilmington and Philadelphia, it said.

Late this afternoon the line of storms was pushing eastward, hammering areas just west of Harrisburg.

Widespread severe weather isn't expected, however the weather service says that the approaching cluster could include a strong thunderstorm packing high winds and "numerous" lightning strikes.

Whatever else the front does, it will break the premature bake-a-thon before it becomes an official "heat wave."

So far, the high temperature today at Philadelphia International Airport is 92, a degree higher than yesterday's. However, it didn't get past 88 on Sunday, and technically a heat wave requires three consecutive days of 90-plus.

That said, Philadelphia probably did set a record today. It didn't get below 74 this morning, and the old record-high minimum for May 29 is 72.

Walter Drag, meteorologist at the National Weather Service in Mount Holly, wasn't quite ready to crown a new champ, noting that a thunderstorm can drop the temperature in a hurry.

For the second straight day, an "excessive heat warning" was in effect in Philadelphia, and for the second day the heat index in Philadelphia topped out at 95, just one degree shy of the early-season threshold for the warning. ("I hope people aren't complaining about it," Drag said this morning.) Until mid-June the thresholds are lower because people aren't quite used to this kind of atmospheric abuse just yet.

Technicalities aside, sources inform us that it's been quiet uncomfortably hot.

May is going to go in the books as the seventh consecutive month with above-normal temperatures in Philadelphia, and the weather service says it is on target to become the fifth-warmest May in records dating to the 1870s.

But it appears that May will end as splendidly as June begins, but the weekend is looking rainy.