San Diego's fire weather warning extended to Saturday afternoon

The fire weather warning that was expected to expire late Thursday on the San Diego County coastline has been extended until Saturday afternoon by the National Weather Service due to the persistent nature of the current Santa Ana winds.

The high wind advisory issued for inland areas has been extended to Friday, from late Thursday.

The Santa Anas roared to life on Monday and fanned a wildfire in Ventura County that’s so large it is visible from orbiting satellites. The winds were weaker in San Diego — but strong enough to lead SDG&E to turn off the power to a slice of East County on Tuesday morning due to the possibility that sparking power lines could touch off a blaze.

SDG&E de-energized a circuit in the Sill Hill area of Descanso, shutting off power to 87 customers as Santa Ana winds started to buffet parts of San Diego County.

The utility also placed outbound dialer calls to customers in Green Valley Falls, Cuyamaca, Viejas and Boulder Creek, alerting them that power outages are more likely in windy conditions and telling them to be prepared with flashlights, extra batteries and an emergency preparedness plan.

SDG&E officials said as a precaution the utility placed SDG&E and contract firefighting crews in areas where winds were forecast to be the strongest.

In recent years, SDG&E has created a weather network that employs three full-time meteorologists and erected 170 weather stations on poles to measure temperatures, humidity and wind speeds. The stations are concentrated in backcountry regions.

SDG&E communications manager Allison Torres said the Descanso area should have its power restored by Friday at the latest but SDG&E crews were patrolling the line, and power could be back as early as Tuesday afternoon

The region was hit Tuesday by a distinct and familiar threat.

A low pressure system settled over the Great Basin, sending winds streaming from the desert toward the sea. The winds shot out of canyons and valleys, hitting speeds that surpassed 80 mph in Ventura, 70 mph in Los Angeles County and 50 mph in the Descano area of eastern San Diego County.

The winds lashed wildland areas that have been dried out by several significant heat waves and a lack of rain. The coast also has been dry; San Diego International Airport received only 0.02 inches of rain in November.

The National Weather Service says the winds, which mostly gusted to 30 to 40 mph in San Diego’s inland canyons and foothills, will fade Tuesday afternoon and be light on Wednesday. But the winds will become explosive on Thursday, gusting 70 to 80 mph across some of San Diego’s inland peaks, and 30 to 40 mph elsewhere.

Here’s a sample of Tuesday’s winds in San Diego County: Sill Hill, 57 mph; North Boulder Creek, 41 mph; Crestwood, 40 mph; Volcan Mountain, 35 mph; Campo, 31 mph; Mount Laguna, 29 mph; Lake Cuyamaca, 29 mph; Julian, 27 mph; Olivenhain, 27 mph; Viejas, 24 mph; Hodges Dam, 23 mph; Ramona, 21 mph.

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gary.robbins@sduniontribune.com

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