UPDATE (7:10 p.m. Sunday):

As of roughly 7 p.m., the tornado watch had been lifted in all three counties where it was initially in effect. 

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Original Story: 

Three northeastern Wyoming counties are under a tornado watch until 10 p.m. Sunday.

Campbell, Crook and Weston Counties are included, as are 11 counties in western and central South Dakota.

Gillette, Wright, Newcastle, Moorcroft, Sundance and Hulett are included in the watch area, according to the National Weather Service.

Area residents are advised to be on the lookout for dark, rotating clouds. Anyone who sees such a cloud or hears a tornado siren should take cover immediately.

Weather updates and emergency instructions will be available via radio or television broadcast.

An EF-3 tornado touched down north of Laramie on Wednesday with winds near 150 mph. Some damage to structures was reported, and steel utility poles were bent.

Four tornadoes -- one rated EF-0, two rated EF-1 and another rated EF-3 -- touched down near Gillette on June 1.

The EF-3 tornado damaged numerous homes and outbuildings, rolled vehicles and snapped power lines. The two EF-1 tornadoes damaged vehicles, buildings and power poles, with the second tornado damaging a building and vehicles at the Eagle Butte Mine and Dry Fork Power Plant.