Overview
- Forecasters said late Wednesday that a weak upper-level trough will move across the Central Coast, triggering onshore flow that will return the marine layer tonight and push low clouds and fog inland through the holiday weekend.
- Temperatures are expected to fall to near-normal by the weekend and run about 5 to 10 degrees below normal next week as the marine influence strengthens and daytime heating is limited.
- Calmer Santa Ana and offshore winds are reducing immediate fire-weather risk, a change that should aid crews fighting blazes, though the Foothill Fire recently grew to about 400 acres.
- Rough seas and strong northerly breezes will keep hazardous conditions for small craft in the northern outer waters through Thursday, with seas and winds forecast to moderate into the weekend.
- The depth of the returning marine layer will determine how far inland clouds, fog, and possible light drizzle reach, and forecasters say a deeper layer would give the best humidity relief for firefighting while interior higher elevations remain very dry.