Issued at 859 AM PDT Wed Jul 22 2026
Widespread drizzle and/or light rain fell over the past 12 hours across the Santa Cruz and Watsonville region this morning with up to 0.12" in the Santa Cruz Mountains around Bonny Doon. In Marin County, Mount Tamalpais also picked up 0.12" as it is a favored upslope region with the southwesterly winds. Isolated spots also picked up a few hundredths of an inch in the East Bay Hills, Big Sur coast, and coastal areas of Sonoma County. This is as the marine layer has returned brining cooler temperatures to the region today, yet mostly sunny skies are expected across the interior by this afternoon.
RGass
, Issued at 148 AM PDT Wed Jul 22 2026 (Today and tonight)
Low clouds and the leading edge of cooler air on southwesterly winds with the eastern side of the northward moving remnant low (once part of tropical storm Elida) rapidly moved to and filled in along the coast Tuesday afternoon and evening. The remnant low is still enveloped by a tropical air mass, but it also has had time to draw in cooler air into the circulation from the northwest. This is the air that'll cool our temperatures today, but it'll also feel muggy and damp today. There may even be a few patches of light drizzle/light rain in the newly arriving moisture rich and cooler air mass combination.
Since about 8 pm to 10 pm Tuesday, an increase in surface dewpoint temperatures (higher water vapor) has spread across about the entire forecast area. Dewpoint temperatures in the 50s and 60s are now widespread.
An area of increasing larger scale subsidence and a clearing sky coincided with maximum diurnal surface heating on Tuesday, boosting daytime highs well above normal including breaking several record high temperatures in our forecast area for July 21st. However, other long term stations such as Santa Rosa, San Francisco, Napa, Kentfield, San Jose and Livermore with a period of record back including July 1917 were in the middle of a several day heat wave this time in 1917; none of these stations reached record highs on Tuesday.
Daytime highs today will be noticeably cooler even far inland: 60s/70s coastside to the 70s/80 bayside and 80s/90s far inland. Lows in the 50s to lower 60s tonight.
..issued at 148 AM PDT Wed Jul 22 2026 (Thursday through Tuesday)
More typically drier (gradually less humid) summer weather develops Thursday onward to the weekend, along with onshore breezes, night and morning low clouds and fog and possibly patchy drizzle. High pressure may compress the marine layer over the weekend bringing a slight warming trend to inland areas.
The latest ECMWF and GFS show dry conditions in the 700-500 mb layer, mostly if not entirely dominated by mid-latitude winds over our forecast area for the next 10 days. Any daytime heating potential instability will be capped by thermal and height ridging at least out through 84 hours according to the 00z NAM model.
(18z TAFS) Issued at 1039 AM PDT Wed Jul 22 2026
An onshore gradient and 1800 ft deep marine layer have kept cigs in place over coastal terminals. Latest satellite imagery depicts a rapidly eroding cloud deck over inland area while coastal stratus persists. Winds remain out of the south to southwest and will gradually veer back to west and NW through the day as the clouds retreat back to the coast. Anticipate an early return to of the marine layer this evening.
Vicinity of SFO, Moderate and occasionally gusty southerly winds will prevail through the morning hours as marine layer hovers near the terminal. Southerly wind have help keep the skies mostly MVFR to IFR. Cigs are expected to make an early return as winds veer to the northwest this afternoon.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, MVFR Cigs are expected to persist through the remainder of the morning then temporarily scatter out in the early afternoon before returning around sunset this evening.
(today through Monday) Issued at 1039 AM PDT Wed Jul 22 2026
A moderate southerly wind will gradually shift to NW through Wednesday afternoon. Winds will increase to a fresh NW breeze Thursday-Friday, with similar conditions continuing into next week. Significant wave heights will remain moderate this week before long period southerly swell from Hurricane Fausto reaches the coastal waters this weekend.
Ca, None. PZ, Small Craft Advisory from 9 AM to 9 PM PDT Thursday for Mry Bay.
Small Craft Advisory from 3 PM Thursday to 3 AM PDT Friday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm.
Small Craft Advisory from 9 AM Thursday to 3 AM PDT Friday for Pigeon Pt to Pt Pinos 0-10 nm.
Small Craft Advisory from 9 PM this evening to 3 AM PDT Friday for Pt Pinos to Pt Piedras Blancas 0-10 nm.
