The stiff Santa Ana winds that stoked a short-lived but dangerous wildfire Monday in Poway were expected to be flat-out wicked before dawn Tuesday in San Diego’s backcountry, where something as minor as the heat from a car muffler could spark a major blaze,

Santa Anas are the desiccating winds that are common in winter, blowing out of Nevada and Utah and into southwestern California. Carrying dry desert air, they push over the mountains in the Transverse Ranges and accelerate as they move downslope, howling into the canyons and valleys.

The Santa Anas are expected to be most powerful Monday night into Tuesday. Fire services across the region say they are ready.