Update: The National Weather Service reports that the previous Fire Weather Watch is now a full Red Flag Warning, after forecasts upped predicated wind speeds to between 20 and 45 miles per hours with gusts included.
According to NWS “a Red Flag Warning means warm temperatures, very low humidities, and stronger winds are expected to combine to produce an increased risk of fire danger.”
Update: The Red Flag Warning now encompasses most of the North Bay, including areas near Calistoga, Petaluma, Santa Rosa, Napa, Cloverdale, and San Rafael, with eastern Napa County at the most risk.
Wind gusts of up to 60 miles per hour may manifest over the weekend.
The National Oceanic and Atmospheric Administration (NOAA) put out a Fire Weather Watch that encompasses a huge swath of Northern California this weekend, including a small part of the East Bay and North Bay, warning that a combination of strong winds and hot, dry conditions pose a significant danger of wildfire.
A Fire Weather Watch means that there is a “high potential for development of Red Flag criteria,” such as winds of 25 miles per hour or greater, low humidity, and “any combination of weather and fuel moisture conditions which, in the judgment of the forecaster, would cause extensive wildfire occurrences.”
Such conditions are not forecast right now—NOAA anticipates winds of up to 20 miles per hours, with gusts reaching speeds of 35, for example—but if conditions take a turn for the worse over the weekend the risk could intensify.
“Any grassfires that develop will likely spread rapidly,” the federal weather agency warns.
The warning is valid from 6 a.m. on Saturday through 1 p.m. or so on Sunday. An earlier warning was set to go into effect on Friday, but subsequent forecasts have narrowed the window.
The affected region extends from Redding in the north through much of Butte County and the Sacramento region and as far south as Modesto, including areas around Stockton.
Most of the Bay Area lies outside of the perimeter of the warning, but places like Antioch, Fairfield, Vacaville, and the eastern edges of Santa Clara, Alameda, and Contra Costa Counties are included.
On Thursday a 15-acre grassfire broke out near Bay Point. Although it only took a few hours for fire crews to achieve significant containment, its position just two miles from the city and timing right on the cusp of a potentially dangerous weekend for fire conditions caused anxiety.
The National Weather Service predicts that temperature in Antioch will soar to as high as 96 degrees this weekend, with highs of 97 in Sacramento and Stockton and 95 in Fairfield.