SAN DIEGO - Gusty winds whipped across inland valley and mountain areas in San Diego County on Saturday, heightening the risk of wildfire, according to the National Weather Service.
The NWS issued a Red Flag Warning for both the inland valleys and mountain areas including the Palomar and Descanso ranger districts of the Cleveland National Forest. The warning expired at 6 p.m.
A Red Flag Warning is issued when high winds combine with low humidity and warmer temperatures to create a risk of wildfire.
"A Red Flag Warning means that critical fire weather conditions are either occurring now or will shortly," according to the NWS. "A combination of strong winds, low relative humidity and warm temperatures will create explosive fire growth potential."
Firefighting staffing levels were ramped up due to the Red Flag Warning.
"We brought additional aircraft from northern California into southern California," said Cal Fire Battalion Chief Nick Schuler. "One additional air tanker in Ramona, one additional air tanker in Riverside… six additional air tankers total in the county available at a moment's notice."
Though the extra staffing is expensive, the resources do not disappear once a Red Flag has expired. Schuler said it is important to keep them in place after the warning expires because the risk of fire remains higher than usual for hours or even a couple of days afterward.
"San Diego County as a whole is extremely prone to having a large fire," he said. "The fuel loading in a lot of places hasn't burned in many years and what is there is either drought stricken and extremely dry. We could have a very large fire."
The agency also issued a wind advisory for San Diego County mountains and valleys that expired at noon. Northeast to eastern winds of between 15 and 25 miles per hour were expected with gusts that could reach up to 50 mph through and below passes and canyons.
Forecasters said the strongest winds would blow near ridge tops, along coastal mountain slopes and the adjacent foothill areas.
The NWS recorded gusts of around 40 mph since midnight in the mountains and coastal foothills.
"The winds will make driving difficult, especially for motorists with high profile vehicles," according to the NWS advisory. "Watch for broken tree limbs and downed power lines."
The winds should gradually diminish throughout the day and become more localized Saturday afternoon, according to the NWS.