Dense Fog — Orange County Coastal Areas, California

2012-11-25 · Orange County Coastal Areas, California

Event narrative

John Wayne Airport ASOS reported visibility of one-quarter mile from 0318 to 0949 PST. Fullerton Airport ASOS reported visibility of one-quarter mile or less from 0253 to 0927 PST.

Wider weather episode

Clear skies, high humidity just inland from the coast, along with the radiational cooling allowed dense fog to form near the coast during the nights and early mornings of the 23rd and 25th. Drainage flow kept the fog within about 10 miles of the coast, with the exception of the inland, low area of Ramona. Multiple airports reported visibilities less than 1/4 mile for several hours on each of those mornings. The fog created some airport delays as well as security problems for the Border Patrol along the Mexican Border and along the coast up to San Clemente.

Source: NOAA Storm Events Database, event_id 418630. Narrative written by the NWS forecast office that issued the report.