Temperatures fall below normal for September

Night through morning low clouds and fog will continue for most coastal areas and lower valleys this week. Onshore flow will produce gusty afternoon winds in the mountains and high deserts. Afternoon high temperatures will remain below normal through the weekend. A warming trend is expected early next week.

Cooling trend continues today and likely through Thursday as well. Marine layer deepened last night as a weak eddy spun up pushing clouds throughout the lower coastal valleys. Likely a similar scenario tonight and slower than usual clearing again Thursday.

Highs tomorrow expected to drop another couple degrees from Wednesday's levels, which puts most areas 4-8 degrees below normal for this time of year. Friday will be very similar to Thursday.

A fairly strong trough will push through the Pacific northwest Saturday into Sunday. The trailing cold front will hold together well enough to bring decent rain to northern California but it will rapidly weaken as it moves southeast and not have any impact locally. As the trough moves into the great basin Monday into Tuesday, surface high pressure will build behind it and possibly create some light offshore flow. There's high confidence that all areas will see a warming trend starting as early as Monday but more so Tuesday and Wednesday with highs getting back to normal and possibly a few degrees above normal.