The fire began shortly after 1 p.m. near North Flynn Road and Interstate 580. Winds gusting to 40 mph pushed the fire east along the hills. It also sent a plume of smoke that settled over Tracy, floating ash into some neighborhoods.
Smoke from the fire was reported as far south as Patterson.
Fire engine crews from Tracy, Alameda County and Cal Fire — a total of about 100 firefighters — along with bulldozer crews tackled the blaze on the ground while they received air support from two tankers and a helicopter from the Cal Fire base in Morgan Hill.
Cal Fire spokesman Daniel Berlant said crews had the fire stopped and 100 percent contained by 3:30 p.m., but crews will be on scene through the night to mop up hot spots.
The high winds through the Altamont made the fire spread quickly in the tinder-dry grass.
“We are in the peak of fire season — the dry conditions through the Bay Area are ripe. Add in the wind, and it can push the fires,” Berlant said.
He added that fire investigators are on scene checking for a cause of the blaze.