California’s Central Valley has been enshrouded in mist for greater than per week due to the world’s notorious tule fog.
The picture beneath reveals California as seen from area by a Nationwide Aeronautic and Area Administration satellite tv for pc system. On the left is what the state seemed like on Oct. 29, 2025 — earlier than a significant storm introduced record-setting rainfall — and on the best is identical view on Nov. 27, in the midst of the days-long stretch of tule fog.
Technically often called radiation fog, the climate phenomenon is the results of a mix of “a cool, moist layer of air from the Pacific near the floor, clear skies above and lightweight winds,” based on the Nationwide Climate Service. Most persistent in valleys the place the wind can’t sweep it away, the tule fog has been a major character in California for many years. It causes pileups, traps airborne pollution and has even impressed poetry about its haunting magnificence.
The NWS forecast reveals many of the Central Valley — together with Merced, Fresno, Visalia and Bakersfield — needs to be spared from essentially the most hazardous circumstances Monday night, then the fog is anticipated to once more thicken in a single day and attain Degree 3 of the climate service’s five-level fog severity index, indicating average danger and half a mile of visibility.
In previous years, tule fog has brought on legendary and tragic pileups alongside Central California highways.
One of many worst such fog-caused chain-reaction accidents concerned 108 autos and closed Freeway 99 for greater than 12 hours in November 2007. The collision unfolded over 10 minutes and resulted in two fatalities and 40 accidents.
As of Monday, no main pileups had been reported after 9 straight days of fog.
The fog shouldn’t be all unhealthy: It’s beloved by growers of crops equivalent to almonds, apricots, cherries, peaches and pistachios as a result of it helps the timber to fulfill the dormancy requirement vital to supply flowers and fruit. The timber want this relaxation interval to supply excessive yields in the course of the rising season.
The California Freeway Patrol means that, if doable, drivers postpone journeys till the fog lifts. These driving in foggy circumstances ought to drive with lights on low beam, the CHP says. Drivers mustn’t observe too carefully behind different autos and will keep away from crossing visitors lanes.
Visibility might be diminished to 10 ft, and the fog might be disorienting, inflicting motorists to drive sooner than they understand. Drivers mustn’t cease on highways besides in emergencies. Drivers and passengers ought to transfer away from disabled autos. Drivers are urged to observe for CHP tempo autos guiding vehicles via the fog.
Occasions employees author Paul Duginski contributed to this report.
