In its final week, the astronomical summer is offering two reminders of why parting won’t necessarily be such sweet sorrow — more thunderstorm threats and another ration of wildfire smoke.

Sometime after sunset Wednesday — and it could be another spectacular one — thunderstorms are possible throughout the region. A severe-storm watch Wednesday is in effect as nearby as Berks and Lancaster counties, with a chance that it could be expanded eastward, said Valerie Meola, meteorologist at the National Weather Service in Mount Holly.

The government’s Storm Prediction Center has the Philadelphia region and much of the Eastern United States under a risk zone for severe thunderstorms on Thursday as a front is forecast to sag through the region.

» READ MORE: Tornado count from last week’s outbreak in Philly region is at 9, and still climbing

After a run at 90 degrees on Wednesday, any storms at least would dampen the recent run of August, with highs Thursday and Friday as much as 10 degrees lower.

They also should help to rout the latest intrusion of wildfire smoke, which could be shaving a degree or two off the daytime temperatures and orchestrating dramatic sunsets, and on Tuesday night painted the half moon a haunting shade of orange.

“It should clear out,” said Meola.

The smoke is 10,000 to 20,000 feet into the atmosphere, said Joseph Bauer, wildfire expert with AccuWeather Inc. The upper-air winds have been favorable for transport, but the No. 1 reason we are seeing so much of it that the wildfires have been ejecting massive quantities into the atmosphere.

So far wildfires have burned over five million acres this year, according to the National Interagency Fire Center, continuing a decadelong trend of increased coverage. The annual average in the 10-year-period is 7.5 million acres, and it’s likely this year’s total will exceed that, said Bauer.

» READ MORE: 10 dead as California fire becomes deadliest of year

Climate change unquestionably is a driver, he said, but it’s had help. Along with the dryness and temperature, a beetle invasion has turned some of the tree stock to kindling, he said.

“We’re seeing multiple things come together,” he said.

And with no sign of the fires abating and the winds willing, Meola said that next week we could well see more evidence of what the West has been enduring.