Warning to mariners:
Web site here.
Specific section: Broadcast Warn.pdf
Page seven includes a warning of missles in this area. Might always be there, but there was a warning.
434/10(18). EASTERN NORTH PACIFIC. CALIFORNIA. MISSILES. 1. INTERMITTENT MISSILE FIRING OPERATIONS 0001Z TO 2359Z DAILY MONDAY THRU SUNDAY IN THE NAVAL AIR WARFARE CENTER SEA RANGE. THE MAJORITY OF MISSILE FIRINGS TAKE PLACE 1400Z TO 2359Z AND 0001Z TO 0200Z DAILY MONDAY THRU FRIDAY IN AREA BOUND BY 34-02N 119-04W, 33-52N 119-06W, 33-29N 118-37W, 33-20N 118-37W, 32-11N 120-16W, 31-54N 121-35W, 35-09N 123-39W, 35-29N 123-00W, 35-57N 121-32W, 34-04N 119-04W.
(Found in the comments on Pharyngla by poster blf.)