A wildfire is forcing the evacuation of a small community in mountains overlooking Tucson.

The Pima County Sheriff's Department says Summerhaven on Mount Lemmon in the Santa Catalina Mountains is being evacuated Monday, but it's not immediately known how many people are affected. Previous evacuations had been issued for lower parts of Mount Lemmon.

Mount Lemmon Highway is closed and Redington Road is closed from mile marker 2 to 14.

Many homes and cabins on the mountain are summertime retreats where Tucson-area residents go to escape the desert heat.

RELATED: More evacuations lifted for the Goodwin Fire

A community meeting is planned for Monday at 5:30 p.m. at Sahuaro High School.

The fire has burned 22 square miles of grass, brush and timber since it was spotted Friday evening in foothills of Redington Pass. At last update, fire officials said it was zero percent contained.

Officials said possible thunderstorms Monday afternoon bring the risk of lightning and erratic winds that could hamper efforts. Conditions are expected to stay hot and dry.

Its cause is under investigation.