Storms, heat to give way to taste of fall

Heat could approach 100 today before cooler, drier weekend

LEWISTOWN - Mifflin and Juniata County residents will have to endure another round of heat and thunderstorms before cooler, drier weather arrives in time for the Labor Day weekend.

John Bowen, a meteorologist with the National Weather Service in State College, said the unsettled pattern that has produced regular afternoon storms will continue through Friday.

"We're kind of in this unsettled pattern where we've been getting regular afternoon showers and thunderstorms across much of our area, and that trend is going to continue for Thursday into Friday," Bowen said.

Another round of showers and thunderstorms is expected Thursday afternoon into the late evening, followed by another chance Friday. Bowen said rainfall totals could range from about a quarter-inch to an inch, depending on whether a heavier storm moves over a particular location.

Before the cooler air arrives, residents will have to deal with another uncomfortable day Thursday.

High temperatures are expected to approach 90 degrees, while dew points climb into the mid-70s. That combination will push heat-index readings much higher than the actual air temperature.

"Could have heat indices approaching 100 for Mifflin and Juniata Counties on Thursday," Bowen said.

The combination of additional thunderstorms and already-wet conditions also raises another concern.

Bowen said the area faced a slight risk, Level 2 of 4, for excessive rainfall Wednesday, followed by a marginal risk, Level 1 of 4, Thursday.

The greatest flooding threat would develop if several heavy thunderstorms move over the same locations in a short period.

"Any time you have repeated heavy thunderstorms over a single area, you start to have concerns for flooding, especially in a short period of time," Bowen said.

Repeated storms could cause creeks and streams to rise and put water across roadways in portions of Mifflin or Juniata counties.

Bowen urged motorists not to attempt to drive through flooded roads because it’s difficult to judge the depth of the water.

"We always say turn around, don't drown, because you never know how deep that water is over the road," Bowen said.

Residents looking toward the holiday weekend should find a much different forecast once Friday's storms move through.

Temperatures are expected to begin falling Friday, when highs should reach the mid-80s. A more noticeable change arrives during the weekend.

"Friday into this weekend, temperatures will moderate and feel like the beginning of fall," Bowen said.

Highs Saturday and Sunday are expected to stay in the mid-to-upper 70s, a drop of roughly 10 to 15 degrees from Thursday's temperatures. Humidity should also become less oppressive.

Bowen said conditions should feel considerably more comfortable than the heat and humidity residents have experienced this week.

The timing should work out well for people with outdoor plans over the Labor Day weekend.

"Saturday should be pretty calm, not expecting any showers or thunderstorms on Saturday or Sunday leading into Monday," Bowen said.

That would leave Saturday and Sunday dry, with quiet weather expected to continue into Labor Day.

The break also appears to mark at least a temporary end to the pattern of frequent showers and thunderstorms that has affected central Pennsylvania.

"So pretty good looking into this weekend once we get through today and once we get through Thursday and Friday as well," Bowen said. "And then it looks like we get a little bit of a break from our unsettled pattern, at least into the start of next week."

For now, Bowen said residents should remain alert for storms through Friday, particularly if thunderstorms repeatedly cross the same areas.

After that, the first weekend of September should provide an early taste of fall.