A shallow marine layer will bring areas of dense fog to coastal Orange and San Diego Counties this evening through Wednesday morning. The visibility will be 1/4 mile or less at times, making driving difficult along coastal roads and highways like I-5 and the 405, and potentially impacting coastal airports.
Patchy dense fog will also extend to Los Angeles County, but it will remain mostly along the coast. In fact, it looks like Downtown will stay mostly clear. Click on the graphic to enlarge.