textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 341 AM PST Sun Mar 1 2026

- A series of troughs will bring cooler weather and cloudier skies through Wednesday

- Strong winds expected along the coast and higher terrain Wednesday through Friday

- Offshore winds will bring warmer and drier weather into the weekend

SHORT TERM

Issued at 1252 AM PST Mon Mar 2 2026 (Today and tonight)

A cut-off surface low is situated just off the coast of Cape Mendocino. The associated upper level low and trough has overran the surface feature and moved inland over northern California. This forward stacking alignment signals weakening of the surface feature as the upper level convergence typically found upstream of the trough is now directly over the surface low. The WPC surface progs support this development, with the surface low weakening from 1016 mb as of 06Z to 1020 mb by 18Z. This evolution is an major hindrance to convection, and I've removed mention of thunderstorms from the forecast for today. That being said, the disturbance will still push trough over the next 12 hours, bringing some isolated areas of light rain and more widespread drizzle through the morning.

LONG TERM

Issued at 1252 AM PST Mon Mar 2 2026 (Tuesday through Sunday)

The long wave pattern is active this week. Following the trough today, a small ridge will build through Tuesday night before another, more neutrally tilted trough, moves through Wednesday. The precipitable water is probably too low to bring any appreciable rain, but this fast moving trough will bring a cold front followed by strong winds. Gale force gusts are possible along the coast and in higher terrain from Wednesday through Friday.

In addition to strong winds behind the front, the skies will quickly clear as much drier air moves in. The PW will likely drop from around 0.6" Wednesday morning to 0.3" Wednesday evening (roughly 75th percentile to 10th percentile for this time of year). This dry air mass is initially coming in from the NW behind the front. As the upper level flow evolves, an inside slider pattern is likely by Friday or Saturday. This will bring persistent northerly, offshore flow through the weekend. The combination of this dry air mass and adiabatic drying from the offshore winds will keep the relative humidity noticeably low, with mostly clear skies. Temperatures will also respond to this pattern, reaching the low to mid 70s next weekend.

Ensemble clusters more or less agree that the dry inside slider pattern will stay around in some fashion through the 9th or 10th, so we don't expect much if any rain in the long term forecast as we head towards the middle of the month.

AVIATION

(06Z TAFS) Issued at 948 PM PST Sun Mar 1 2026 The new picture from space shows low clouds infiltrating the region, with TAF sites slowly succumbing to MVFR cigs. Radar scanned a few areas of extremely light reflectivity over the water this evening; however, those never really made it to land. Any light showers or drizzle should develop later tonight, likely closer to the early morning hours. Opted to push mention of drizzle back and keep most cigs around MVFR and hinted at IFR cigs due to lower confidence in that area. Conditions improve mid to late morning, with clearing skies for the afternoon and evening.

Vicinity of SFO...A batch of stratus has made it to SFO this evening, perhaps an hour or two earlier than expected. Cigs are expected to hold at MVFR for at least a few hours, perhaps flirting with periods of VFR if they don't stay landlocked. Any chances for drizzle or light rain should happen after 9Z, if the models are right, and then wrap up mid morning. Clouds will gradually lift or mix out, leading to VFR conditions by late morning or early afternoon. There is some signal at lower clouds returning early Wednesday morning, perhaps between 10-13Z. Confidence was too low to add at this time.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Well we cleared out for a bit this evening, but that was short lived as the stratus has returned. Given the games the stratus has been playing tonight, confidence is a bit lower in whether or not it will stick around all night. Opted to keep the more pessimistic forecast of MVFR cigs and hint towards IFR later should we get any drizzle. Cigs should begin to lift by mid to late morning, with VFR conditions expected for tomorrow afternoon.

MARINE

(Tonight through next Saturday) Issued at 948 PM PST Sun Mar 1 2026

A few showers will be possible north of the Golden Gate tonight through early Monday as a weak system moves through. Seas continue to subside through Wednesday. By Thursday seas build as high pressure strengthens over the eastern Pacific. The building high will result in northwest winds to gale force and steepening seas over 12 feet.

MTR WATCHES/WARNINGS/ADVISORIES

CA...None. PZ...Small Craft Advisory from 2 PM this afternoon to 3 AM PST Tuesday for Pt Pinos to Pt Piedras Blancas 0-10 nm.