With summer about two-thirds gone, at least in a meteorological sense, Greg Harmon of the National Weather Service compared temperature readings so far with those of past years and discovered Sioux Falls readings are tied for the fifth-coolest on record.

The record books go back to 1889.

Harmon says summer for meteorologists is June through August.

Why have temperatures been cooler? Harmon says part of the reason is an established upper-level low over southeastern Canada, known as a Hudson Bay low that has persisted since May. He says it brings Canadian air into the Upper Midwest.

Harmon doesn't see many changes for the rest of summer, predicting that says readings likely will remain at or slightly below normal into August. Also, he says September could be cooler and wetter than normal with a warmer trend from late October into November and December.

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