Wind, high-90s heat returning soon to Northern California. Will weather affect fires?
It’s officially fall, but in a few days, it sure won’t feel like summer ended in Northern California.
After high temperatures in the more seasonally normal mid-to-high 80s the rest of this workweek, Sacramento is expected to hit 93 degrees on Saturday and 98 on Sunday. Next Monday and Tuesday could reach 99, according to the latest National Weather Service forecasts.
Those highs would be close to 15 degrees above average for late September, currently forecast to come within a few degrees of the daily records for Sept. 27-29. Sacramento’s all-time mark for each of those dates is 102 degrees, according to the local NWS office.
After downtown Sacramento exceeded 110 degrees twice in the middle of August, a historically hot month for the capital, 99 degrees may not sound as sinister as it normally would this time of year.
Temperatures will be similarly high throughout the Sacramento Valley and above-average for most of interior Northern California. Highs should remain in the 80s or low 90s throughout most of the Sierra Nevada foothills. South Lake Tahoe is expected to reach the low 80s beginning this weekend.
The bigger concern, outside of the immediate Sacramento area, is the return of gusty winds throughout the northern half of the state.
Wildfire weather conditions in forecast
The NWS has issued a fire weather watch for parts of Northern California, in place Saturday through Monday mornings. The advisory includes much of the greater Bay Area, as well as the foothills east of Sacramento and the northern third of Sacramento Valley.
Fire risk will be elevated in those regions due to sustained winds between 10 to 20 mph, and gusts that could reach about 30 mph, combined with dry conditions and poor humidity recovery overnight, the NWS says.
A fire weather watch is one level below a red flag warning, which indicates critical wildfire weather conditions are imminent. Red flag warnings typically aren’t issued until closer to 24 hours before the start of windy weather; they frequently start as a fire weather watch, and are upgraded as the weather event approaches and wind forecasts become more accurate.
California has already been ravaged this year by record-setting wildfires, including five of the six largest in recorded state history that have sparked in the last six weeks, all in Northern California or the Bay Area.
This weekend’s gusty winds have the potential to impact those large existing wildfires, including the North Complex burning in Butte and Plumas counties, plus the biggest-ever August Complex burning at Mendocino National Forest.
To date, about 3.4 million acres have burned statewide in 2020 among nearly 8,000 total wildfire incidents handled by Cal Fire and the U.S. Forest Service, ranging from minor to major. At least 26 people have died.
The fall, particularly the period before its first significant rainfall, is generally California’s worst stretch of wildfire season because gusty winds start to pick up in regions where vegetation has grown increasingly dry over the summer.
The NWS predicts there may be some light showers Thursday, but isolated to the far northwest corner of the state. The weather service doesn’t currently predict any widespread precipitation for Northern California in the near future.
