A wildfire burning in and near Lory State Park northwest of Fort Collins exploded to between 750 and 1,000 acres Friday, pushed by erratic winds, record temperatures and low humidity.

Live blog: Updates from the Galena fire

Officials said they sent out 860 evacuation phone calls. The evacuations to the north of the fire, where the first 281 calls were made, have been lifted. A second round of 579 calls, for homes to the south of the fire, went out at about 3:30 p.m. The Poudre Fire Authority said those evacuations would remain in effect through the night. The fire was 5 percent contained at 8:30 p.m.

More than 100 firefighters were working on the Galena fire — originally reported as being named the Soldier Canyon fire — but no aircraft could be used because of high winds. The winds also were driving the fire, which was first reported at about 11:45 a.m. by a person who called 911, said Capt. Patrick Love, a Poudre Fire Authority spokesman.

Photos: View more images from the Galena fire

“Winds have been extremely erratic,” Love said.

A smaller, second fire was also reported Friday, in LaPorte just off County Road 54G and east of Overland Trail. That fire was reportedly contained late Friday afternoon.

About 50 homes, and the park, were initially evacuated in the Galena fire.

Additional evacuations were issued at about 3:30 p.m. for areas south and west of Horsetooth Reservoir north of Larimer County Road 38E. Feeder streets to Shoreline Drive in the vicinity of Inlet Bay and north, up to and including Continental Circle, are part of the evacuation areas.

There were roadblocks at Lodgepole and County Road 23 on the north end of the fire and at Shoreline Drive and 38E and Skyline and 38E in the south part of the fire-evacuation area.

Also, search teams were looking for any hikers who might still be in the state park.

“We want to locate those individuals and escort them out of the park,” said Executive Officer Nick Christensen, a Larimer County Sheriff’s Office spokesman.

Horseshoe Mountain Park is among the areas that have been closed. The Horsetooth Reservoir is closed for boating. Other closures will be considered Saturday.

Firefighters are concerned that the blaze has started to run south, toward open ground and homes.

Earlier Friday, three structures — two homes and the parks’ visitors center — were saved by fire crews, Christensen said. Now there are about 50 homes that are threatened.

Additional resources have been called in, but there is a concern that aircraft can’t fly at night, Christensen said.

Love added that some of the wildfire resources are in winter mode and not immediately available.

A Type III incident command team will take over operations Saturday morning.

An evacuation center has been set up at Cache la Poudre Elementary School gymnasium in LaPorte.

The cause of the fire is under investigation.

Saturday’s forecast offers some reasons for optimism.

Temperatures will be cooler but will remain above average, and winds are expected to be lighter Saturday, according to the National Weather Service.

Robert Koopmeiners, a meteorologist with the Weather Service, said winds should start to taper off after 8 p.m. Friday, although winds of 10 to 15 mph were likely to remain overnight.

The area also has a 40 percent chance of rain Saturday.

But at least with more clouds and higher humidity, the situation could improve, Koopmeiners said.

The fire is within about one-fourth of a mile of the High Park fire, which started last June to the west just over a ridge top. The High Park fire scorched 87,284 acres and cost $38.4 million to battle.

On Friday, the Larimer County health department issued a news release warning that air quality in Larimer County could change frequently throughout the day.