PENNSYLVANIA, USA — The lingering summer heat pushed central Pa. into yet another heat wave Tuesday, with temperatures exceeding 90 degrees for a third straight day.
2023 has already seen the hottest month in recorded weather history this July, with dry conditions across much of the Commonwealth this season. Despite Labor Day being the unofficial end of summer and it being meteorological fall, high temperatures have lingered into the start of the new season.
THE QUESTION
Is it uncommon to have a September heatwave in central Pennsylvania?
OUR SOURCES
National Weather Service Meteorologist David Martin
National Weather Service climate summary database xmACIS2
WHAT WE FOUND
Data from the National Weather Service shows that, with this latest heat wave, there have been 24 in the month of September in our area since record-keeping began in 1888.
David Martin has been a meteorologist since 1987. He says heat this late in the summer is not uncommon.
"We get it once in a while in early September. When you get to later September it is harder," Martin said. "The last few years we’ve been seeing more warm weather in the fall."
Martin says there are a variety of factors that come into play with high temperatures.
"In order to get really hot, one thing that makes it hotter is if it’s not really wet," Martin said. "Plus this source region, a lot of this heat is coming in from the midwest and southwest."
So no, heatwaves in September are not uncommon in central Pa.
According to the EPA, the frequency, duration, and intensity of heat waves nationwide have steadily increased since the 1960s.
Martin says the summer heat in the Commonwealth has followed that pattern. The average last 90-degree day in Harrisburg each year is August 30, though still lingers into the start of fall.
"We’ve been seeing a trend in the last 10 years where it’s fairly common to extend the summer into September or early October," Martin said.