All lanes of east and westbound SR 18 are blocked near Tiger Mountain Summit (MP 24).
According to State Trooper Rick Johnson, there was a semi vs. motorcycle collision. The passenger from the motorcycle has serious injuries. State Troopers are investigating the incident.
#Breaking EB SR 18 is completely blocked near Tiger Mt. summit due to a semi/motorcycle collision. Passenger from motorcycle has serious injuries. Witnesses advised the semi forced the motorcycle into the barrier. Updates to come.
— Trooper Rick Johnson (@wspd2pio) August 14, 2026
Emergency crews are on scene. Travelers should expect delays.
Issaquah-Hobart Road Southeast and city streets are not suitable for freight traffic.
UPDATE: Both directions of SR 18 just west of Tiger Mountain Summit (MP 23) are blocked due to a collision.
— WSDOT Traffic (@wsdot_traffic) August 14, 2026
Emergency crews are on scene. Expect delays.
Please note: Issaquah-Hobart Road Southeast and city streets are not suitable for freight traffic. https://t.co/lTaQJ4lO7y pic.twitter.com/p9TKthReF2
This is a developing story and will be updated as information becomes available.
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