A "dangerous" winter storm was expected to dump up to 18 inches snow across much of the Plains and the Midwest on Tuesday, with blizzard and white-out conditions forecast for many areas.
Winter-storm alerts were in effect across at least eight states from Wyoming to Michigan, with strong winds likely to snarl travel and make roads hazardous. Some areas could even see lightning and thundersnow, the Weather Channel said.
Heavy snow was affecting Colorado, Nebraska and parts of Iowa early Wednesday. More than 300 flights were already canceled as at 6 a.m. ET, FlightAware reported, with Denver, Colorado, the hardest-hit airport.
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