FLAGSTAFF, Ariz. — It may be May 22, but Arizonans in the northern part of the state will experience what the National Weather Service in Flagstaff called an "unusual late-season winter storm."

NWS Flagstaff said "significant" snow is in the forecast for northern Arizona overnight.

There will be periods of rain and snow starting Wednesday that will last through Thursday morning, according to NWS Flagstaff. The heaviest snow, however, is expected to fall Wednesday night through Thursday morning in areas above 6,500 feet.

The snow and ice will cause hazardous driving conditions late Wednesday and for the early-morning commute Thursday, NWS Flagstaff said.

The latest forecast shows Flagstaff could see 2 to 4 inches of snow, while places like Williams could see up to 6 inches.

There is a shot of rain and showers in the Valley later Wednesday into Thursday morning. The storm system will keep temperatures low Wednesday with a high of 76 degrees, a similar high in Fairbanks, Alaska.

NWS Phoenix also referred to the weather pattern as "unusual."

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