, Issued at 209 PM PDT Fri Jul 18 2025 (This evening through Saturday)
While the morning was overcast across much of the region, stratus has now dissipated across much of the interior. Building high pressure is expected to compress the marine layer to around 1500 feet tonight. This is still a fairly deep marine layer so we can expect stratus to return across much of the Bay Area and Central Coast by late tonight into early tomorrow morning. Stratus will clear by late tomorrow morning across the interior with clearing occurring for portions of the coastline. Further compression of the marine layer is expected Saturday night into Sunday as high pressure strengthens over the Central Coast with the marine layer depth dropping to around 1200 feet.
Seasonal temperatures will continue again on Saturday as a slight warming trend continues. For the Bay Area, temperatures will stay in the upper 70s to low 80s along the bay shoreline with highs in the mid to upper 80s farther inland. Coastal areas will remain comparatively cooler with highs in the upper 50s to mid 60s on Saturday. The interior Central Coast however will be quite a bit warmer with high temperatures in the mid to upper 90s. Portions of far southern Monterey County in the vicinity of Fort Hunter Liggett, Bradley, and Parkfield have 40% chance of temperatures reaching the 100 degree mark. Temperatures cool down into the 50s overnight across the Salinas Valley and upper 50s to mid 60s across the higher terrain. This results in Minor HeatRisk across the Bay Area and Central Coast with only a few pixels of Moderate HeatRisk in the Los Padres National Forest.
Localized fire weather concerns continue in particular for the interior Central Coast and East Bay Hills. For the interior Central Coast, daytime conditions are expected to further dry Saturday and poor daytime humidity values between 13 to 25 percent expected. Fortunately, winds remain light and onshore across the higher terrain, where the driest conditions are, which will help mitigate concerns a little. The Salinas Valley, comparatively, will continue to experience breezy afternoon/evening winds with gusts to around 30 to 35 mph. Conditions are not quite as dry in the Salinas Valley but occasional moderate gusts (up to 25 mph) may push into the far southern Salinas Valley (vicinity of Bradley) where conditions are drier. For the East Bay Hills, we can expect dry daytime conditions (humidity values between 25 to 30%) and breezy afternoon winds to around 35 mph across mountain gaps/passes to continue through the remainder of the weekend.
..issued at 209 PM PDT Fri Jul 18 2025 (Saturday night through next Thursday)
Weather wise, Sunday looks to be a repeat of Saturday with temperatures in the upper 70s to 80s across the interior with a few hot spots in the East Bay reaching the low 90s. Highs across the interior Central Coast will start cool, if ever so slightly, with highs peaking in the mid to upper 90s compared to upper 90s to low 100s anticipated on Saturday. While high pressure remains situated over much of California on Sunday, it does start to break down late in the day as another upper level trough moves into California. As this trough approaches, it will increase onshore flow and allow gusty winds to develop Sunday afternoon along the coast and across mountain gaps/passes throughout the interior. Gusty winds will become more widespread on Monday across the North Bay, San Pablo and Suisun Bays, along the delta, and across the East Bay hills (emphasizing mountain gaps/passes). Gusts are expected to peak around 30 mph across the North Bay but will peak closer to 35-40 mph across portions of the delta and East Bay Hills (Altamont Pass).
Hopefully you aren't tired of No Sky July and comparatively mild temperatures as the arrival of this trough will also kick off a cooling trend and bring a return to below normal temperatures across the region. Temperatures across the interior will drop back into the 70s to low 80s and remain that way through the end of the week as troughing continues. The exception will again be the interior Central Coast where temperatures will only drop into the upper 80s to low 90s. All in all, the CPC indicates below normal temperatures are likely to persist through late July with near normal temperatures to persist into the first few days of August.
In terms of fire weather concerns, localized concerns will still exist across the highest elevations but the return of upper level troughing will help to mitigate more widespread concerns. Increased onshore flow will allow for modest improvements in daytime humidity values starting Monday. This is most noticeable across the interior Central Coast where daytime minimum values will improve from around 13 to 20% over the weekend to 20 to 30% by early next week.
(18z TAFS) Issued at 1033 AM PDT Fri Jul 18 2025
MVFR currently over the Bay Area terminals and areas just inland way from the coast. However, IFR conditions continue across coastal sites this morning and very well may linger through much of the day. Inland TAF sites such as LVK and SJC have cleared out and the rest of the inland terminals look to clear out by late morning. Look for onshore winds to increase this afternoon before easing after sunset this evening. High confidence for IFR/MVFR conditions to return to much of the region again this evening and into Saturday morning when we have low probability of seeing ceilings lower to LIFR, greatest potential over the North Bay and Monterey Bay terminals.
Vicinity of SFO, High confidence for MVFR ceilings to scatter out and/or clear by 18Z-19Z with onshore winds increasing this afternoon. High confidence for MVFR ceilings to return late this evening with the low confidence for IFR ceilings as we head into early Saturday morning. Expecting low clouds to diminish a bit later tomorrow between 19Z-20Z as the marine layer is forecast to compress slightly. Once low clouds clear, look for an increase in onshore winds once again.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, IFR/MVFR ceilings currently at the TAF sites but clearing should occur soon at SNS. MRY looks to see MVFR ceilings through about 21Z, yet may linger through a good portion of the day. High confidence for IFR/MVFR ceilings to make an early return this evening with a low probability of LIFR conditions heading into Saturday morning.
(tonight through next Wednesday) Issued at 209 PM PDT Fri Jul 18 2025
Light to moderate west or northwest breezes continue across the majority of the coastal waters through this weekend with winds easing into the upcoming week. Gusty winds, potentially hazardous to small craft, develop each afternoon and evening through the Golden Gate, into the Delta, and the favored coastal jets off of Pigeon Point and the Big Sur coastline. Moderate seas persist through the remainder of the forecast period.
Ca, None. PZ, Small Craft Advisory until 3 AM PDT Saturday for SF Bay N of Bay Bridge.
Small Craft Advisory from 9 AM Saturday to 3 AM PDT Sunday for SF Bay N of Bay Bridge.
Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt to Pt Pinos 0-10 nm.
Small Craft Advisory until 9 AM PDT Saturday for Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory from 3 PM Saturday to 3 AM PDT Sunday for Pt Arena to Pt Reyes 10-60 NM.
