Eastbound State Route 18 was completely blocked near the Tiger Mountain summit on Friday afternoon after a semi-truck collided with a motorcycle, leaving the motorcycle's passenger with serious injuries. Witnesses reported that the semi-truck forced the motorcycle into the barrier during the crash.
The collision was first reported around 3:45 p.m. Friday by WSDOT Traffic, the official Washington State Department of Transportation account covering King and Snohomish counties, including Seattle. The agency, which is monitored 6 a.m. to 6 p.m. Monday through Friday, retweeted an update from the Washington State Patrol District 2 public information officer, who said further updates would follow. WSDOT Traffic also advised drivers to call 911 to report road hazards.
A Familiar Danger Zone on Tiger Mountain
Friday's crash adds to a troubling pattern along the SR 18 corridor over Tiger Mountain, a stretch that has seen repeated serious collisions involving motorcycles and commercial trucks. Just two months earlier, a 19-year-old Covington man riding a motorcycle was killed in a rear-end collision with a Volvo semi-truck along the same westbound stretch, an incident that shut the highway down for two and a half hours, according to the Kent Reporter. Hoodline also reported on that fatal crash at the time.
The mountain pass is one of the busiest and most freight-dependent corridors in the region, carrying roughly 27,000 vehicles daily between Interstate 5 and Interstate 90, per FOX 13 Seattle. Narrow mountain conditions and heavy commercial truck traffic have historically forced full closures whenever major collisions occur, since single-lane bottlenecks leave little room for emergency crews to work around a blocked roadway.
Infrastructure Upgrades Haven't Eliminated the Risk
WSDOT completed a $188 million widening project in October 2025, adding two lanes in each direction and a permanent concrete median barrier along a two-mile stretch of SR 18 between I-90 and Deep Creek, according to KIRO 7. Hoodline covered the project's early completion in a $188 million fix that opened early. The median barrier was designed specifically to curb cross-median crashes, but steep grades and single-lane sections near the summit continue to generate serious accidents, particularly those involving semi-trucks and motorcyclists.
That risk was on display again in October 2025, when a FedEx semi-truck crashed off westbound SR 18 near the Tiger Mountain summit at milepost 25, plunging into roadside trees and seriously injuring the driver. That incident closed lanes for more than nine hours during recovery, as tow crews carried out multi-hour winching operations, according to MyNorthwest.com. Construction-era data compiled by Eastside Fire & Rescue previously showed a 75% increase in collisions along SR 18 in 2023 compared to the prior year, which the Snoqualmie Valley Record attributed largely to temporary lane restrictions during active construction.
Motorcyclists Remain at Disproportionate Risk
Friday's crash also lands squarely within what Washington law enforcement agencies call the “100 deadliest days,” the summer stretch between Memorial Day and Labor Day when roughly 30% of the state's annual traffic fatalities occur, per KIRO 7. Nearly 60% of the state's annual motorcycle fatalities happen during these warm-weather months, according to Washington Traffic Safety Commission data.
Statewide, motorcyclist fatalities dropped to 109 in 2025 from a peak of 139 in 2024, but riders still account for about 16% of state traffic deaths despite making up just 3% of registered vehicles, the Washington Traffic Safety Commission found. Overall, Washington recorded 659 traffic deaths in 2025 preliminary reporting, a 10.5% decrease from 2024 and an 18% decline from the 33-year peak of 809 fatalities set in 2023.
Under Washington law, RCW 46.37.530 and RCW 46.61.610 require all motorcycle operators and passengers to wear DOT-certified helmets, and passengers are only permitted if the motorcycle has a permanent seat and foot pegs designed for two-up riding, according to WMST. It remains unclear whether witness accounts of the semi forcing the motorcycle into the barrier point to aggressive driving, an improper merge, or a lane-discipline violation, and investigators have not said whether equipment standards for the motorcycle's passenger were met.
No further details on the cause of Friday's collision or the condition of those involved beyond the passenger's serious injuries had been released as of the latest update from the Washington State Patrol. Hoodline will update this story as WSDOT Traffic and state troopers release more information.
