A wildfire erupted in Grand County Wednesday afternoon, prompting pre-evacuation orders for two zones near Granby.

The Windy Gap fire, estimated at about 30 acres with 40% containment as of Thursday morning, prompted the Grand County Sheriff to issue a pre-evacuation order for zones G41 and G48 near Granby, the Grand County Sheriff’s Office said on Facebook Thursday afternoon.

The zones make up area along U.S. 40 and Highway 125 west and northwest of Granby, respectively, the evacuation map shows.

After being initially closed due to the proximity of the blaze Wednesday night, U.S. 40 was partially reopened on Thursday to accommodate alternating one-way traffic, the Grand County Emergency Management webpage says. Highway 125 remained open with a flagger controlling traffic.

Authorities are asking drivers on the roadways to be extra attentive for crews and trucks fighting the fires, officials told 9News. Two helicopters and one single-engine air tanker responded to the fire, dropping water on the blaze to help slow its spread.

An investigator on the scene determined that lightning caused the fire, the Facebook post says. Crews assessed that five uninhabited small cabins on the property were destroyed in the fire.

No injuries have been reported thus far.

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