Rain check: Philadelphia seeing higher than average precipitation

Data from the National Oceanic and Atmospheric Administration shows 33 inches of precipitation pummeled Philadelphia between January and July. (Creative Commons image)

Data from the National Oceanic and Atmospheric Administration shows 33 inches of precipitation pummeled Philadelphia between January and July. (Creative Commons image)

This year, Philadelphia is experiencing higher than average precipitation.

Data from the National Oceanic and Atmospheric Administration shows 33 inches of precipitation pummeled Philadelphia between January and July.

The city recorded 40 inches of precipitation in all of 2017, and the annual average is 46.

Surrounding counties are also seeing higher numbers. Chester County, for example, has gotten 36 inches, more than 8 inches above average.

Alan Cope, the science and operations officer for the National Weather Service, said global warming is having an impact.

“As the atmosphere warms, it’s capable of containing more moisture. And that moisture, from time to time, is going to fall out as heavy rain,” he said.

This leads to showers over a short time, which can then lead to the flooding that’s become commonplace in parts of the region.

Forecasting rain or snowfall beyond seven days is too error prone, Cope said, so there’s no way to tell how much the city will have by year’s end.

“The matter of how much rain is going to fall is one of the most difficult things to predict,” he said.

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