Tule fog lingers across the valley, prompting safety and health warnings

February 7, 2026 - 15:53

A thick blanket of Tule fog has stubbornly lingered across the valley for several weeks, significantly reducing visibility and creating hazardous conditions for residents. The dense, ground-level cloud has become a major concern for transportation officials and health authorities alike.

On roadways, the fog has been a primary factor in dangerous multi-vehicle collisions, including serious pileup crashes on major arteries like Highway 99. Authorities are urging drivers to use extreme caution, recommending reduced speeds, use of low-beam headlights, and increased following distances. Travel is advised only if absolutely necessary during the heaviest fog periods, typically overnight and into the early morning.

Beyond the immediate traffic dangers, the persistent fog also raises public health considerations. The stagnant air can trap pollutants close to the ground, potentially aggravating respiratory issues such as asthma and bronchitis. Health officials suggest that individuals with pre-existing conditions limit prolonged outdoor exertion while the fog advisory remains in effect.

The Tule fog, a hallmark of California's Central Valley winters, forms under specific conditions of cool, moist air following rainfall. While a familiar seasonal occurrence, its unusual duration and density this year have amplified risks, making public adherence to safety warnings critically important.