REDWOOD CITY, San Mateo County, Calif., Oct. 13, 2026 — A multi-vehicle crash with reported injuries shut down lanes on southbound US-101 near Woodside Road on Sunday morning, October 11, according to the California Highway Patrol. The pileup involved several vehicles and prompted a request for ambulance response.
The California Highway Patrol received a call about multiple collisions reported in close succession just north of the Woodside Road exit beginning around 7:26 a.m. Early reports described a gray sedan colliding with a gray SUV, and a separate vehicle striking a barrier on the right side of the freeway. Additional calls described a white pickup truck colliding with a gray sedan, and another report of a white Chevrolet hitting a silver Acura sedan.
One vehicle reportedly left the roadway and went into an embankment, with its front end caught under a guardrail. A report of smoke coming from one of the involved vehicles was also reported, though the CHP report does not specify whether anyone was trapped or how serious any injuries were. One caller reported that a white pickup had been driving recklessly, weaving in and out of lanes, before the crash.
The CHP requested ambulance response to the scene and closed the Woodside Road onramp to southbound 101 while crews worked the collision. At least two tow trucks were called to clear vehicles from the roadway and shoulder area. The exact number of people hurt and the extent of any injuries have not been released.
This crash remains under investigation. The California Highway Patrol has not released additional details on what caused the initial collision or how many vehicles were ultimately involved.
We wish the injured a complete and speedy recovery.
When Multi-Vehicle Pileups Are Most Likely to Happen
Morning commute hours bring a mix of conditions that can turn one fender-bender into a chain-reaction crash. Traffic is dense, speeds are inconsistent as some drivers rush to work and others ease into the day, and low morning sun or fog can cut visibility on stretches like 101 through the Peninsula. A single car braking hard or drifting can trigger a cascade before following vehicles have time to react.
Weekday mornings and evenings, when commuter volume peaks, see more of these pileups than overnight hours, simply because more cars are packed closer together at higher speeds. Winter months add wet pavement and reduced visibility to the mix. Fatigue and distraction also tend to climb during the early commute, when drivers are less alert than they realize.
According to the Insurance Institute for Highway Safety, 17,008 motor-vehicle crash deaths occurred outside passenger vehicles in crashes involving passenger vehicles in 2023. That figure is a reminder that the people most exposed in these multi-car incidents are often not the drivers who caused them.
Frequently Asked Questions
How does fog or low visibility contribute to pile-ups?
Reduced sight distance means drivers have less time to spot slowing traffic ahead. A chain of vehicles traveling close together can collide in sequence once the first car brakes or stops.
Why is following distance so important?
Extra space between vehicles gives drivers more time to react to sudden braking or lane changes ahead, which can stop a minor slowdown from turning into a multi-car collision.
Are secondary crashes common after an initial wreck?
Yes. Vehicles that stop or slow to avoid an earlier crash can themselves be struck from behind, especially on busy highways where traffic keeps approaching at speed.
What makes multi-vehicle crashes hard to investigate?
With several vehicles and drivers involved, determining the sequence of impacts and who struck whom first often takes time and combines physical evidence, vehicle damage patterns, and witness accounts.
What to Do After a Multi-Vehicle Crash in Redwood City, CA
If you're involved in a pileup, try to stay in your vehicle with your seatbelt on unless it's unsafe to do so, and turn on hazard lights to warn approaching traffic. Call 911 to report injuries and request help, even if you feel fine immediately afterward, since some injuries take hours to show symptoms.
Once safe, exchange information with other drivers involved and, if you're able to do so without stepping into traffic, take photos of vehicle positions and damage. Seek a medical evaluation promptly, as whiplash, concussions, and internal injuries are not always obvious at the scene. Keep a copy of the CHP or police report for your records once it becomes available.
