SAN DIEGO (KGTV) - Santa Ana winds are expected to heighten San Diego County's fire risk this weekend.
The National Weather Service issued a fire weather watch for San Diego County late Sunday night into Thursday afternoon for "strong gusty winds" and low humidity.
"High pressure aloft near the west coast and surface high pressure over the great basin will bring an extended period of very low humidities and periods of gusty northeast winds," according to the NWS alert.
WEATHER: 10News daily conditions and forecast
According to the US Forest Service's Santa Ana Wildfire Threat Index, San Diego County will see a moderate risk Monday, escalating to a high risk on Tuesday. Wednesday will see a marginal risk before seeing a return to moderate risk on Thursday.
High risks are categorized as fires that will grow very rapidly, burn intensely, and be very difficult to control. Moderate risks are fires will grow rapidly and be difficult to control. Marginal risks say fires may grow rapidly.
A prolonged period of Santa Ana conditions will develop early Monday & persist until the end of the week. This will likely bring a lengthy period of gusty winds, very low relative humidity w/ poor recoveries overnight, & critical fire conditions for SoCal. #cawx #SanDiegoWX pic.twitter.com/xsjvhwdJZb
— NWS San Diego (@NWSSanDiego) December 2, 2017
Easterly winds of 25 to 35 mph and gusts of 60 to 70 mph with isolated higher gusts are possible, strongest in the mountains and foothills, according to 10News reporter Melissa Mecija. Humidity can drop between 5 and 15 percent as well.
Cal Fire officials expect the fire danger to be comparable to that experienced in the Bay Area prior to wildfires which occurred earlier this year.
The lack of measurable rain has contributed to the high fire danger.