SIOUX FALLS, S.D. (AP) — The National Weather Service says wind chills in South Dakota are dipping to near 40 below.

Readings hit 39 below in Huron and 33 below in Sioux Falls at 5 a.m. Monday.

The northern part of the state has been under a wind chill warning, which will shift to an advisory later in the morning that will last through Tuesday morning.

Nearly the entire state showed air temperature readings below zero, with a couple of locations reaching 23 below.

The Weather Service says those temperatures, combined with winds forecast at 5 mph to 10 mph west of Interstate 29 and 10 mph to 20 mph east of the highway, are creating dangerous conditions.

Meteorologists advise that people who have to venture outdoors wear appropriate clothing, including hats and gloves.

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