, Issued at 1017 PM PDT Thu Aug 20 2026 (Friday and Friday night)
Improved onshore flow in the lower boundary layer especially for the North Bay and Bay Area should result in more extensive stratus intrusion overnight coinciding with overnight lows closer to normal for this time of year. Warm and dry conditions will continue both overnight and through the day above 1000ft inland and near the coast, this includes in vicinity of the Timber Fire where relatively light winds continue to be a mitigating factor. Some elevated convection earlier Thursday night has tapered off or now in the steering flow of the ridge. Any mid/upper level moisture attempting to reach the Central Coast would be greeted by anemic instability and confluent flow aloft.
As the closed portion of the upper level low responsible for the persistent troughing recently will slowly approach the Oregon coast later tonight with a steady fetch of onshore flow continuing across our area, with only a marginal increase in depth of the marine layer expected into early Saturday morning.
..issued at 1017 PM PDT Thu Aug 20 2026 (Saturday through next Thursday)
The parent low mentioned above moves onshore into the PacNwest during the day Saturday with a weak troughing pattern lingering offshore at our latitude through at least the weekend. However, the persistent ridging over the Desert Southwest will shift east as well during this time , thus we'll continue to see the cooling trend through the weekend into the beginning of next week. There's a weak signal for the ridging to the east to build back toward the west coast by the middle of next week, which would bring warmer temperatures, but at that point a potential tropical system well to our southwest may add noise to the NWP.
(06z TAFS) Issued at 849 PM PDT Thu Aug 20 2026
It's VFR except onshore winds will usher stratus and fog /MVFR-IFR- LIFR/ inland tonight and Friday morning. Patchy coastal drizzle is possible tonight and Friday morning. Conditions improve to MVFR-VFR late morning and afternoon Friday.
Vicinity of SFO, Stratus /MVFR-IFR/ continues tonight and Friday morning, with mix out to VFR forecast 19z Friday. Stratus /MVFR/ returns Friday night and Saturday morning. West-northwest wind 15 to 25 knots until 08z tonight then easing to 12 to 15 knots tonight and Friday morning then increasing to 15 to 25 knots Friday afternoon and evening.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, Stratus, fog /MVFR-IFR-LIFR/ and possibly a few patches of drizzle developing tonight and Friday morning. Conditions improving to MVFR-VFR Friday afternoon. Stratus /MVFR-IFR/ returns Friday evening and night. West to northwest winds 5 to 15 knots.
(tonight through next Wednesday) Issued at 841 PM PDT Thu Aug 20 2026
Northwest moderate to fresh breezes persists into the weekend with higher winds expected near the coastal jet regions of Point Reyes and Point Sur. Occasional strong gusts are possible across the outer waters and coastal jet areas through Saturday. Wind driven seas remain slight at the coastline and quickly build to moderate across the outer waters through the weekend.
Ca, None. PZ, Small Craft Advisory until 3 AM PDT Friday for Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM.
Small Craft Advisory from 11 AM to 9 PM PDT Friday for Pigeon Pt to Pt Pinos 0-10 nm.
Small Craft Advisory until 3 AM PDT Saturday for Pt Pinos to Pt Piedras Blancas 0-10 nm.
