, Issued at 1245 AM PDT Sat Jun 20 2026 (Today and tonight)
The pattern overall will remain similar today as a broad upper level trough sits overhead. Stratus will expand across most areas this morning within a marine layer around 3000 feet deep. Drizzle may develop along the coast this morning as well, resulting in locally slick roadways. The deep marine layer and continued onshore flow will keep temperatures similar to yesterday, with highs along the coast ranging from the upper 50s to around 70. Inland, temperatures will remain below normal with highs reaching the 70s to lower 80s. Clouds should retreat back to the coast this afternoon, giving way to sunny skies in most areas. However, clouds may not fully erode in coastal areas due to onshore flow and orographic effects. Onshore winds will once again be breezy this afternoon and evening with gusts 15-30 mph, strongest in gaps/passes.
The marine layer will begin to compress tonight as the upper level trough weakens. Marine stratus will still fill in most valleys tonight, but the extent should be lower overall. Patchy fog will also be possible along the coast and in wind-sheltered valleys.
..issued at 1245 AM PDT Sat Jun 20 2026 (Sunday through Friday)
The upper level trough will continue its weakening trend on Sunday and the marine layer will compress further. Decreasing marine influence and warming temperatures aloft will begin a warming trend, especially inland, where many locations will reach the 80s, with a few readings approaching 90 degrees in the warmest spots. The warming trend will continue Monday and Tuesday as a broad ridge builds across the western U.S. Highs will reach the 80s and 90s through the week across the interior. Hot temperatures will be accompanied by the potential for Moderate HeatRisk and increased heat impacts, although overnight cooling limits concerns somewhat. Closer to the coast, confidence in the temperature forecast is lower, but at least some warming is expected. More significant warming along the coast/SF Bay shoreline could develop if a weaker onshore or offshore wind pattern occurs, but confidence in this scenario is low. This potential will continue to be monitored as we head into next week.
As mentioned in previous discussions, ensemble guidance continues to indicate moisture rotating north around the upper ridge centered over the Desert Southwest. By Wednesday and Thursday, there is a low (around 10%) chance that the moisture and accompanying instability makes it far enough west to bring a threat for thunderstorms to the Bay Area and Central Coast. Overall, the chance of this scenario occuring is low, but it could have a large impact. While the current forecast package does not include thunderstorms, this potential will continue to be closely monitored over the coming days.
(12z TAFS) Issued at 442 AM PDT Sat Jun 20 2026
Low clouds have settled into coastal areas and adjacent valleys this morning. Some areas may see patchy drizzle with very light accumulations. Stratus will recede back off land around 17 to 19Z Saturday with VFR conditions prevailing through the early evening. Low clouds returning to most coastal TAF sites near 1500-2000ft after 04Z Sun, after 06Z for areas further inland.
Vicinity of SFO, Weaker SW winds expected through the morning. Cigs scattering out with winds increasing near 15 kts after 19Z Saturday. Cigs returning similar timing to last evening ~ 07Z Sun, though lower near 1500-1800ft. Confidence in timing moderate to high, confidence in cig heights moderate.
SFO Bridge Approach, SW wind pattern is similar to SFO. MVFR cigs clearing at a similar time to SFO this morning, becoming VFR by 19Z. Cigs 1500-1800ft returning slightly earlier than SFO (03-04Z Sunday).
Vicinity of SJC and OAK, MVFR ceilings scattering near 17-19Z, confidence higher for earlier clearing at SJC. Typical diurnal winds out of the W/NW this afternoon. Cigs near 1600-1900ft returning earlier at OAK (05-07Z Sun) than SJC (10-12Z Sun), lower confidence in exact timing of cig impacts at SJC.
Monterey Bay Terminals, Cigs near 2500-3000ft this morning will scatter out around 18-20Z with moderate confidence on timing. VFR conditions prevail through the afternoon with cigs returning near 04-06Z Sun near 1500-1800ft. Typical diurnal winds out of the W/NW expected Saturday across the bay.
(today through Thursday) Issued at 308 AM PDT Sat Jun 20 2026
Light winds today will increase across the northern outer waters later tonight and persist through early Monday morning, while remaining relatively light across the remainder of the inner and outer waters. Long period southwest swell is likely to continue through the remainder of the extended forecast period.
Issued at 308 AM PDT Sat Jun 20 2026
Long period southerly swell at around 15 to 17 seconds will persist for the remainder of the weekend, and increase to 17 to 19 seconds by the middle of the upcoming work week as energetic storms in the Southern Hemisphere continue to affect the California coast, especially for south and southwest facing beaches. Hazardous beach conditions are advertised, specifically for moderate to steeply sloped beaches along the Pacific Coast of the North Bay, San Mateo, Santa Cruz counties. A Beach Hazards Statement for Pacific Coast beaches continues through Wednesday afternoon. Be sure to check beach conditions before you head out. Sneaker waves will run up the beach much farther than other waves, potentially catching beachgoers by surprise and resulting in people being swept into the water. Rip currents are strong enough to pull the strongest swimmers away from shore. Swim near a lifeguard if possible. Stay back from the beach, and away from jetties, piers, beachside rocks, and other infrastructure near the water. Never turn your back to the ocean!
Ca, Beach Hazards Statement through Wednesday afternoon for CAZ006- 505-509-529-530.
PZ, Small Craft Advisory from 9 PM this evening to 3 AM PDT Monday for Pt Arena to Pt Reyes 10-60 NM.
