Report: Westmoreland home to Western Pa.’s tornado alley, wildest weather
Westmoreland is hit by more tornadoes than any other county in the region, and local weather experts can’t explain exactly why.
The National Weather Service’s severe weather climatology report for the Pittsburgh region counted 30 tornadoes in Westmoreland County from 1950-2013. Mercer County had the second-most in the region, at 19.
The weather drama doesn’t stop at twisters, the report shows.
Allegheny County and Westmoreland get far more reports of severe hail than any other in the region, 278 and 226, respectively, since 1955. Mercer County’s 115 hail reports make it a distant third.
Allegheny tops the weather service’s count of severe wind reports, with 545 since 1955. Westmoreland is second with 526, trailed by third-place Jefferson County’s 346.
Westmoreland’s high ranking in wild weather events is something of a mystery to local experts.
“I wish I could give you an answer, but I don’t have one,” said Tom Green, a meteorologist with the National Weather Service in Moon.
One reason for the anomaly is Westmoreland’s population, which is higher than many other counties in the region, Green said. The weather service’s data are largely based on first-hand reports from residents. Many tornadoes are very short-lived, and if nobody is around to spot one, it may never become part of the official record.
“The more people there are, the more likely a tornado, or the wind damage, is actually seen,” Green said.
However, that doesn’t fully explain why Westmoreland has so many more tornadoes than its neighbors, especially more-populous Allegheny County, which has had only 16 recorded twisters since 1950, according to the report, which covers 36 counties in Western Pennsylvania, Eastern Ohio, Northern West Virginia and Western Maryland.
Westmoreland’s tornadoes are a frequent subject of discussion among local experts, but there isn’t enough data to lead to any concrete theories, said WPXI meteorologist Scott Harbaugh.
“There are numerous theories. In Pittsburgh you’re told growing up that we don’t get many tornadoes around here, because of all the hills and valleys. And you’d think with the Laurel Highlands, that would rule Westmoreland County right out,” he said.
Meteorologists’ understanding of twisters still has some gaps, Harbaugh said. Even in the Midwest, where the flat, open land makes tornadoes much more common, experts are unable to explain why one area is more affected than others.
Harbaugh suspects the steep change of altitude from the Monongahela River to the Laurel Highlands mountains influences Westmoreland’s penchant for tornadoes.
“The air is automatically forced up, and when air is forced up it helps to create stronger cells and stronger thunderstorms,” he said.
However, that theory doesn’t account for the rotation necessary for tornadoes to form, and there are still too many unknown variables, Harbaugh said.
Westmoreland emergency officials have learned to prepare for the worst when it comes to weather, said Roland “Bud” Mertz, director of the county Department of Public Safety.
“That’s something we have to prepare for and plan for as much as we possibly can, he said. “When you have severe weather issues you have a whole host of other problems that come with it.”
He remembers working as a first responder in the 1980s, when high winds ripped apart a Greensburg apartment complex.
“I remember seeing several buildings that were devastated,” he said.
He works closely with the weather service to prepare for the worst, and he urged families to create their own emergency plans in case of a weather disaster.
“No two storms are the same,” he said.
Jacob Tierney is a staff writer for Trib Total Media. He can be reached at 724-836-6646 or [email protected]