According to KTVU's Gasia Mikaelian, a fire on Yerba Buena Island is affecting traffic on the Bay Bridge. It's on the west side of Yerba Buena just under the bridge. It is not inside the tunnel, you see, but on the vegetation on the hill. So far one lane is blocked on the southwest side of the bridge. You might want to re-plan your commute home; there's no guess as to when the fire will be put out.

The bridge traffic seen from outside SFist HQ is slooooow, we should point. So, yeah, might want to take another bridge come 5 p.m. More to come.

Update I: No word yet on any eastbound closures. Now word yet on the cause of fire.

Update II: KRON 4 reports that the CHP "is shutting down the entire upper deck of the Bay Bridge and one lane of the lower deck while crews battle a massive fire on Yerba Buena Island."

Update III: Traffic on Third Street and Bryant has come to a standstill. Looky-loos on the bridge have nothing better to do than watch your SFist editor work/watch . Leave us be!

Update IV: Gasia Mikaelian is really on this story. What's more, she looks like fun. Yay! We've found new on-air talent to stalk adore. Anyway, they've got live footage of the blaze in action here.

Update V: Fire is out. Nothing to see here, folks. Move along.

Tyra