The Santa Ana Wildfire Threat Index categorizes Santa Ana winds based on anticipated fire potential. The five-day forecast is showing a moderate level fire threat beginning Thursday, Dec. 3, then decreasing to marginal on Friday, Dec. 4.
There is no rating for Saturday and Sunday, but a moderate threat level is expected again Dec. 7-8.
The index created by the U.S. Forest Service uses a comprehensive, state-of-the-art predictive model that includes the moisture level in dead and live vegetation that can fuel fires and the greenness of annual grasses to create a detailed daily assessment of the fuel conditions across Southern California.
The moderate level of fire threat warning indicates that upon ignition, a fire would grow rapidly and be difficult to control. The index’s forecast is as follows:
Northeast to east winds of 20 to 30 mph with gusts to 50 mph will surface across the mountains and below the canyons and passes. Widespread single digit humidity will accompany these offshore winds. Temperatures will be around 5 degrees above normal, and be in the 70s across the lower elevations. Fuels will be critically dry due to the long duration of extremely dry days ahead of this offshore wind event.
Friday’s forecast: Local northeast winds of 10 to 20 mph with gusts to 35 mph will surface across the mountains and below the canyons and passes throughout the day. There will continue to be widespread minimum humidity in the single digits and teens. Temperatures will remain 5 to 10 degrees above normal, with 70s across the lower elevations. Fuels will continue to be extremely dry.
There is no rating for Saturday and Sunday, but the Index is expecting a return to moderate levels Dec. 7-8.
This year has already seen five of the top six fires in California history ignite. The seventh largest fire in state history, the Thomas Fire, began in Dec. 2017. Overnight Thursday, the newly ignited Bond fire caused mandatory evacuations in canyon areas of central Orange County.
Source: Orange County Register
Be First to Comment