Marine Weather and Tide Forecast for South San Francisco, CA

SHORT TERM
(This evening through Saturday)
Issued at 1253 PM PDT Fri Jun 13 2025

Our story continues with a very seasonably quiet weather pattern across the CA coast. Minor fluctuations in the marine layer height will continue to cause some day-to-day differences in humidity across some of the higher terrain around 2,000 feet. Otherwise it's much of the same for most of us closer to sea level. As of writing, there has been a new fire start south of Hollister. The good news is that it isn't particularly windy in the area and should see good humidity recovery overnight.

LONG TERM
(Saturday night through next Thursday)
Issued at 1253 PM PDT Fri Jun 13 2025

Looking into the longer term; A few small perturbations in the upper level flow that stay to our north will help tamp down the effects of a broad upper level ridge. This will keep temps a few degrees below seasonal normals pretty much across the board. We do see a *slight* warming trend towards the end of the period mid next week as the ridge builds over the West Coast, but nothing terribly notable at this point. Perhaps high temperatures near normal by the middle of next week. Would not be surprised if we see additional grass and vegetation fire starts over the next several days - like the one mentioned near Hollister - as grasses and fine fuels are very dry and susceptible to catching fire.
Again, the good news is that we are looking to stay under a seasonable onshore flow regime throughout the forecast period.

AVIATION
(00Z TAFS)
Issued at 506 PM PDT Fri Jun 13 2025

VFR conditions prevail at the TAF sites this afternoon, with little to no stratus being observed across the Bay Area and Central Coast. Profilers show that the marine layer near Bodega Bay is sill around 1500ft which should support the redevelopment of stratus tonight. The challenge will be, just how far inland does it go? Favored the inherited TAFs, though added some possibility for stratus at KSJC and removed windshear at the North Bay terminals.
Will need to keep an eye on KLVK as some guidance has entering the vicnity of the range ring.

Vicinity of SFO...High cloud streams over the San Francisco region.
Area webcams are showing similar features and perhaps a few low clouds lingering, matching the METAR for KSFO and KOAK. The marine layer is roughly around 1500ft and should generally hold tonight.
Guidance for SFO is a bit mixed, but opted to favor the HRRR, GLAMP, and NBM guidance for timing out the return of the stratus tonight which is similar to a persistence forecast. Expect MVFR to IFR CIGS with conditions improving by late morning. There may be some pesky lingering low cloud again tomorrow, otherwise expect VFR conditions for the afternoon and early evening. The stratus signal for tomorrow night generally favors an after 06Z arrival, though opted to hint at that with it arriving around 05Z. In addition to the stratus, gusty west to west-northwest will prevail.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...The region has mostly cleared out, with stratus lingering on the edge and just offshore of the Monterey Peninsula. Expect stratus to fill back in tonight, likely around or after 06Z. Given we still have a few clouds to the west of KMRY, I tried to hint at the possibility of stratus returning earlier this evening perhaps closer to 03Z. Confidence was too low to go anything other than FEW and opted to trend more optimistic with clearing occuring late in the morning.

MARINE
(Tonight through next Thursday)
Issued at 506 PM PDT Fri Jun 13 2025

Fresh to strong northwesterly breezes, near gale force gusts, and moderate to rough seas will prevail through Tuesday. Localized gale force gusts are expected near the coastal jet regions of Point Reyes and Point Sur during the afternoon and evening hours.

FIRE WEATHER
Issued at 359 PM PDT Fri Jun 13 2025

Another veg fire, Lime Fire, developed in the interior Central Coast again this afternoon. This will be a common theme over the weekend as elevated fire weather conditions prevail.
Night/morning marine layer will remain with cooler temperatures and excellent humidity recovery at lower elevations. Above the marine layer (higher hills/mts) and areas not directly impacted by the marine layer will see moderate to poor humidity recoveries.
The lack of humidity recovery will keep finer fuels, like grasses, drier and more susceptible to fire starts. Additionally, given the onshore flow winds will be gusty each afternoon/evening for inland valleys (Salinas Valley), and gaps/passes.

The large view for the interior Central Coast shows ERC values barely exceeding average, burn index close to seasonal averages, and 100 hr fuel moisture slightly below seasonal averages.

Marine layer will hover 1700-2100 feet the next few days.

MM

MTR WATCHES/WARNINGS/ADVISORIES
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Mry Bay- Pigeon Pt to Pt Pinos 0-10 nm.

Small Craft Advisory until 3 AM PDT Sunday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.

Small Craft Advisory until 9 AM PDT Saturday for Pt Reyes to Pigeon Pt 0-10 nm.

Small Craft Advisory from 3 PM Saturday to 3 AM PDT Sunday for Pt Reyes to Pigeon Pt 0-10 nm.

Small Craft Advisory from 3 PM to 9 PM PDT Saturday for Pigeon Pt to Pt Pinos 0-10 nm.