Weather Alert

National Weather Service updates average temperature, rainfall data

DES MOINES — When you hear the average temperature or rainfall during the weather, that’s typically based on the past three decades of information, and this month the National Weather Service updated that temperature and precipitation data.

Doug Kluck, the weather service’s Central Region climate services director, says they roll the averages forward every ten years. “We’re taking 1991 through 2020 compared to 1981 through 2010, so that’s a ten-year adjustment forward in a 30-year full period,” Kluck says. “We’re going to see how much the climate has changed in those ten years.”

Kluck says the new numbers show a cooling trend across the Northern Plains states, which includes Iowa, Minnesota and the Dakotas. “Guess what happened in the last ten years across the Northern Plains, what have we seen up there? An abundance of what? Not necessarily cold air, but an abundance of moisture, right?” Kluck says. “We’ve had some pretty wet years, let’s say, in the last ten across the Northern Plains, thus, the temperatures are dampened a little bit.”

While most of the nation is trending warmer with the shift in the decades of averages, Iowa and its neighbors are seeing a cooling trend. “Other parts of the country, not so much,” he says. “If you go to the West, especially in the Southwest, you’re going to see a lot more increases in temperature when you compare the last 30-year period to the new 30-year period.”

As for the Northern Plains, Kluck says they’re seeing cooler temperatures lingering longer in the spring, with warmer temperatures pushing further into the fall.

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