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 and lasting through Dec. 5.
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 warned for later this week 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.
This year has already seen five of the top six fires in California history ignite.
Source: Orange County Register