Storm damage after the tornado hit in Trevose, Pa., on July 29 during a
© TYGER WILLIAMS
Storm damage after the tornado hit in Trevose, Pa., on July 29 during a "rare" tornado outbreak.
The year-to-date annual tornado numbers are running below normal nationally, no thanks to what has been happening in Pennsylvania and New Jersey.

Both states already have well-exceeded their twister averages for an entire year, bumped up by the "rare" supercell outbreak of July 29 that included one with Tornado Alley-like 140 mph winds, and last week's Fred-related twisters, one of which traveled almost nine miles.

So far in 2021, 19 tornadoes have touched down on Pennsylvania soil, three above the 30-year annual normal and eight more than what would be the average total through August, according to the government's Storm Prediction Center.

Typically, only one would have touched down in Jersey by the end of this month; so far, eight have, which is quadruple the annual average. Two others have visited Delaware.

In a comprehensive analysis and summary report posted this week, the National Weather Service Office in Mount Holly said that the July 29 event, which added 10 twisters to the three-state totals, was ignited by the complex interactions of upper-air and surface systems that created an "unusually favorable" environment for powerful thunderstorms.

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