UPDATE 3:30 p.m.: All lanes of Interstate 5 through the Grapevine are now open.
GRAPEVINE: Northbound I-5 has just re-opened in Castaic, all lanes on the Grapevine are open and clear! Please exercise caution as traffic clears out following the closure. @CaltransHQ @CaltransDist7 @CaltransDist10— Caltrans District 6 (@CaltransDist6) December 6, 2018
California Highway Patrol has closed both sides of Interstate-5 over the Grapevine.
There are reports of several accidents due to weather conditions.
Check back for updates.