The National Weather Service has issued a fire weather watch for this weekend throughout the Sacramento and San Joaquin valleys.
A fire weather watch means that critical fire weather conditions are expected to occur. The watch was issued as a result of low humidity coupled with gusty winds that could reach nearly 30 mph in Stockton.
The combination of gusty winds and low humidity can cause a fire to grow rapidly in size and intensity. Outdoor burning is not recommended.
The strongest winds are expected across the Sacramento Valley along and west of Interstate 5, the Delta and the northern San Joaquin Valley, according to the weather service.
The watch goes into effect at 8 a.m. Saturday and continues through 11 a.m. Sunday.
On Friday, a high of 77 degrees with sunny weather is expected in Stockton, before dipping to a low of 55 degrees with clear skies overnight.
But by Saturday, the temperature is expected to climb to 81 degrees, and Sunday is forecast to be even hotter, with a predicted high of 85 degrees. Daytime humidity will drop to 15% to 25%, one of the reasons spurring the weather service’s fire weather watch.
Power shutoffs ahead of the fire watch are already underway in parts of San Joaquin County. Pacific Gas & Electric Co. initiated public safety power shutoffs in seven Central Valley counties that had affected more than 2,200 customers as of Thursday afternoon, according to the company.
Severe weather, such as high winds, can cause trees or debris to damage utility equipment, according to PG&E. If there is dry vegetation that ignites when touching a live power line, it can cause a wildfire. The utility preemptively shuts down power to locations that could pose hazardous during high-wind events.
PG&E plans public safety power shutoffs, or PSPS, when the following factors could contribute to the risk of wildfire:
- Low humidity
- Forecasted high winds
- Dry material on the ground
- Vegetation near powerlines
- Red flag warnings from the National Weather Service
- Real-time ground observations
On Friday, PG&E said that parts of San Joaquin County and 14 other counties could be affected by public safety power outages that could last through the weekend.
As of 9 a.m., the utility had reported 1,077 customers without power in San Joaquin County.