10/22/2026
STARTING TOMORROW: SR-37 CLOSURE SCHEDULED FOR THIS WEEKEND
A 55-hour full closure of SR-37 between Vallejo and SR-121 is scheduled to kick off tomorrow night (Friday, October 23 at 10 p.m.) and run through the weekend with a planned reopening of 5 a.m. on Monday, October 26.
If you are traveling eastbound on SR-37 (Marin/Sonoma Counties to Vallejo):
Motorists traveling eastbound on SR-37 will need to exit left onto northbound SR121 in Sonoma; Make a right on SR-12/SR-12, 1(Carneros Hwy) and continue; Right on SR-12/SR-29; Enter left for the connector loop Off-ramp back to EB SR37. (See attached graphics)
If you are traveling westbound on SR-37 (Vallejo to Marin/Sonoma Counties):
Motorists traveling Westbound on SR-37 will need to exit right onto northbound SR-29 in Napa, and follow SR 29 to WB SR 12 then to SB SR 121. (See attached graphics)
Please plan ahead and expect significant delays on detour routes through Napa County. If travel through these areas is necessary, please plan extra time to make it to your destination.
CHP personnel will be present at the closure and additional personnel have been scheduled to patrol the detour routes for the duration of the closure to help ensure everyone makes it to their destination safely.
Please remember, 9-1-1 is for emergencies that require an immediate response from emergency personnel. Please do not call 9-1-1 to ask for traffic updates. Caltrans Bay Area-District 4
For real time traffic updates, visit www.511.org or utilize your favorite GPS service.