, Issued at 1206 PM PDT Mon Sep 14 2026 (This evening through Tuesday night)
Today will be the warmest day of the upcoming week with a slight cooling trend kicking off tomorrow. The upper level trough that brought us cooler weather last week has progressed eastward towards the Intermountain West. In its place, zonal flow has developed over Central California with slight troughing to redevelop Tuesday. The transition from more zonal flow to slight troughing will see temperatures cool 2-5 degrees across the region. This will bring interior temperatures down from the mid to upper 80s today to the low to mid 80s tomorrow. Coastal areas stay cooler with highs in the 60s to 70s.
Moderate offshore winds were observed along the ridgeline of the Vaca Range early this morning but have since been trending downwards. Mt. St. Helena (elevation of 4340 ft) reported a NNE gust of 40 mph at 2:40 AM which was the strongest wind gust observed from this event. The SFO-WMC gradient peaked at -6.10 around 7AM this morning and has since dropped to -4.90 as of 10AM. It is forecast to shift positive (onshore) by late this afternoon with light onshore winds returning everywhere. The return of onshore winds should help marine stratus to redevelop/move inland tonight. The only caveat to this is we currently have a dry airmass over us which could keep stratus development limited for one more night. Breezy onshore winds redevelop Tuesday afternoon and evening with gusts to around 20-30 mph most likely in the East Bay Valleys, Salinas Valley, higher elevations, and directly along the coast.
..issued at 1206 PM PDT Mon Sep 14 2026 (Wednesday through next Sunday)
Troughing becomes more dominant by Wednesday as another upper level low pushes into the Oregon/California border. We are not anticipating any rain or thunderstorms for this system across our region but it will bring an unusually cold airmass across our region. High temperatures Wednesday and Thursday will be running 5-6 degrees below normal across the lower elevations and closer to 10-15 degrees below normal in the higher elevations and along the coast. This will keep interior temperatures securely in the 70s and coastal temperatures in the low to mid 60s. Favored hotspots across the interior Bay Area and Central Coast will reach the low 80s. The upper level low deepens and tries to become cut-off from the jet stream Thursday into Friday. Fortunately, it is a quick moving system and maintains a neutral tilt. If it took a more positive tilt and dug in more over NE California/Nevada then it would be more reminiscent of an inside slider which would raise offshore wind concerns. As it stands right now, this system will just bring a round of gusty onshore winds Wednesday into Thursday with gusts peaking between 20 to 30 mph. Locally higher gusts are possible at favored windy locations (Altamont Pass, higher elevations, etc.). The passage of the upper level trough will allow the marine layer to deepen and see a return of our nightly/early morning stratus along the coast and portions of the interior.
Troughing influence wanes Friday into the weekend as weak ridging builds in over California. This will see a gradual return to more seasonal temperatures in the low to mid 80s across the interior, 60s to 70s along the coast, and upper 80s to low 90s across favored hot spots in the Bay Area and interior Central Coast. Even though the ridge is weak, it will still compress the marine layer and most likely result in less stratus cover across the interior.
(18z TAFS) Issued at 1004 AM PDT Mon Sep 14 2026
VFR at all terminals this morning with onshore winds forecast to increase through the afternoon before easing after sunset. However, the forecast wind speeds will be less than previous days. Moderate confidence for the return of stratus over the Bay Area terminals tonight with higher confidence for the Monterey Bay terminals. Onshore winds increase once again by Tuesday afternoon.
Vicinity of SFO, VFR. Onshore winds are forecast to increase throughout the afternoon with gusts up to 25 kt before gradually easing late in the night. Moderate confidence for stratus at around 1500 feet to arrive around 10Z Tuesday before scattering out by 17Z. However, the HRRR does not suggest ceilings make it over SFO. Thus, leaning more on the NBM and GFS-LAMP guidance.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, VFR. Onshore winds increase this afternoon and gradually diminish after sunset. Moderate to high confidence for IFR/MVFR ceilings to return late this evening and into Tuesday
(today through Saturday) Issued at 1004 AM PDT Mon Sep 14 2026
Hazardous conditions for small craft will continue for the coastal waters and Monterey Bay early in the week due to a northwesterly moderate to fresh breeze with strong gusts. Northwest winds will ease by mid-week. Moderate to rough seas will prevail through Tuesday before subsiding Wednesday.
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 Tuesday for Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 3 AM PDT Wednesday for Pt Arena to Pt Reyes 10-60 NM.
Small Craft Advisory until 9 AM PDT Tuesday for Pigeon Pt to Pt Pinos 10-60 NM.
