Dense tule fog has settled over California’s Central Valley for days, sharply reducing visibility and contributing to a string of serious crashes across Fresno County and surrounding areas. Meteorologists say the fog is not a one-off event. The National Weather Service office in Hanford says a persistent high-pressure pattern has kept conditions stable, allowing moisture to condense overnight and rebuild thick fog each morning. In some parts of the Valley, the fog has lingered into the afternoon. Across Fresno, Clovis, Selma, Laton, and nearby communities, visibility has dropped to just a few hundred feet at times, creating dangerous conditions on highways and local roads.
Massive pileup on Highway 99 near Delano
The most severe crash occurred Saturday morning on Highway 99 near Delano in Tulare County, where dense tule fog sharply reduced visibility during peak travel hours. According to the Tulare County Fire Department, at least 59 vehicles were involved in a chain reaction collision that unfolded around 8:17 a.m.
Officials said drivers encountered a sudden wall of fog that limited visibility to approximately 100 to 200 feet, leaving little time to react as traffic slowed ahead. Once the initial collisions occurred, additional vehicles continued striking one another in rapid succession across multiple lanes.
The crash forced Highway 99 to shut down in both directions between Avenue 24 and the Kern County line for several hours as emergency crews worked to reach injured motorists, clear damaged vehicles, and remove debris from the roadway. Authorities reported multiple injuries ranging from minor to moderate, though no fatalities were immediately confirmed in that incident.
Images from the scene showed dozens of cars and SUVs clustered tightly together, some heavily damaged, as firefighters and medical personnel moved between vehicles to assist occupants. The incident underscored how quickly fog conditions can overwhelm even experienced drivers on one of the Central Valley’s busiest transportation corridors.
If you were injured in or near Delano during a fog-related collision, it may help to speak with a Delano car accident lawyer about what steps to take next, especially in multi-vehicle crashes where fault and insurance coverage can quickly become complicated. To discuss your situation, contact Bojat Law Group for a free consultation at (818) 877-4878.
Crashes reported across Fresno County
A woman injured in the fog-related multi-vehicle pileup on southbound Highway 99 in Fresno has died, according to the California Highway Patrol.
CHP said the woman was traveling in the same vehicle as 61-year-old Gustavo Villanueva Vargas, who died during the January 11 pileup. A verified GoFundMe for the family identified the woman as their grandmother, Gloria Rodriguez, and said the family was on the way to church when the crash happened. The fundraiser said Rodriguez died three days after the collision.
Officials said the crash occurred when a sudden, thick patch of fog overtook the southbound lanes, leaving drivers with extremely limited visibility and triggering a chain reaction involving 17 vehicles. CHP said Vargas died after getting out of the vehicle during the incident. A family update stated that Vargas’ wife remained hospitalized and another relative was also recovering.
More injuries reported in fog-related crashes
Beyond the major pileups, law enforcement responded to several other fog-related crashes across Fresno County. In Clovis, a teenage driver was critically injured after her van collided with a semi-truck during foggy morning conditions. School districts in Clovis and Madera delayed bus schedules by three hours due to unsafe visibility on local roads.
Longtime Central Valley drivers and instructors said this season’s fog has been unusually thick and persistent, lingering through entire days instead of burning off by mid-morning.
Why tule fog is so dangerous
Tule fog is a dense ground fog unique to California’s Central Valley. It often forms overnight when moisture condenses under stable weather patterns and can appear unevenly, leaving clear stretches of roadway that suddenly disappear into near-zero visibility.
Officials warn that drivers frequently underestimate how much fog affects stopping distance. Moisture from the fog can also settle on the roadway, reducing traction and increasing the risk of rear-end and chain reaction crashes.
Authorities urged motorists not to rely on automatic headlights, which may not activate rear lights during daylight fog conditions. Drivers are advised to slow down well below posted speeds, increase following distance, and remain alert, especially on highways carrying heavy commuter and truck traffic.
How to stay safe in dense fog
Dense Tule Fog Triggers Chain Reaction Crashes in Central Valley 2
- Slow down immediately. Reduce your speed well below the posted limit when visibility drops, even if traffic around you is still moving quickly.
- Turn on low-beam headlights. Use manual low beams so both headlights and taillights are visible. High beams can reflect off fog and make visibility worse.
- Increase following distance. Leave extra space between vehicles to allow more time to react if traffic slows suddenly.
- Avoid sudden braking or lane changes. Gradual movements help prevent chain reaction collisions in low visibility.
- Use road markings as a guide. Follow lane lines and reflectors rather than focusing on vehicles ahead that may disappear in the fog.
- Pull over only when necessary. If conditions become too dangerous to continue, exit the roadway or pull well off the shoulder and turn on hazard lights.
- Delay travel when possible. When a Dense Fog Advisory is issued, postponing travel can reduce the risk of serious crashes.
Fog expected to persist
Meteorologists say the conditions responsible for the recent fog are expected to continue, meaning drivers across the Central Valley may face similar hazards in the days ahead.
The recent crashes serve as a stark reminder that while fog is a natural weather phenomenon, its impact on modern, high-speed roadways can be severe. As officials continue investigating the incidents, drivers are being urged to treat dense fog as a serious hazard and adjust their driving accordingly.
Share:
