At around 12:30 this afternoon, Alert SF sent out the following message:

"Please avoid the area of 5th and Brannan; an incident has caused power outage and traffic impact. It is anticipated that the power outage affecting approximately 2,000 persons in the area will be resolved."

The reason? A banner fell off a plane while it was flying over the area. KGO has a pic of the aforementioned banner. Bizarre.

No injures were reported.