A wind-driven wildfire broke out in the hills of Southern California Tuesday night as late season Santa Ana winds blasted down burning slopes toward homes.

Gusts of wind are sending flames racing across the brush in Anaheim Hills in Orange County. The fire is burning on the east side of a roadway, which is functioning as a firebreak, Fire Authority Capt. Greg McKeown said.

Fire crews are trying to keep it on that side because there are homes on the west side, less than a mile from the freeway. State Route 241 was ordered shut down in both directions, McKeown said. No homes have been evacuated but he urged residents to get ready.

Downslope winds are throwing embers into the air, which could start spot fires, he said.

Firefighters made good progress on an upwind flank, but if the fire jumps the road, residents will have to evacuate the expensive neighborhood quickly.

Fire engines were parked on the freeway as crews lay hoses amid swirling smoke and erratic winds. About 30 engines and 90 firefighters were on the scene after officials called for extra firefighting resources.

Firefighting helicopters and aircraft usually don't fly at night for safety reasons, but some have night vision technology that allow them to see in dark and smoky conditions.

The National Weather Service said humidity levels in the area were forecast to drop into the single digits overnight. Sustained winds are predicted to blow at about 15 to 25 mph with gusts of 35 to 50 mph.

The notorious Santa Anas usually sweep in between October and February as dry air descending from the Great Basin flows toward Southern California and squeezes through mountain passes and canyons.

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