Issued at 854 AM PST Fri Nov 13 2026
KMUX radar is indicating a narrow cold-frontal rainband (NCFR) approaching the North Bay at this hour. Brief heavy downpours are likely with the NCFR but will ease in intensity as the front moves through the Bay Area and north Central Coast through the afternoon. Thus, expecting the strongest winds just ahead of the NCFR with gusts up to 50 mph along in the higher terrain, along the coast, and in the favored passes and gaps. Timing has't changed much from the earlier Short Term discussion. No changes anticipated at this time.
RGass
, Issued at 1200 AM PST Fri Nov 13 2026 (Today and tonight)
KMUX radar is showing echoes from pre-frontal showers across the coastal regions from Big Sur to Sonoma County with some rainfall already being reported along the coastal ranges and other favored areas. So far tonight, around 0.14" have been reported at the Big Sur RAWS and 0.05" at the Oak Ridge RAWS in the Sonoma County coastal ranges. The isolated pre-frontal showers should continue through the night.
The weather picture features a deep upper level low centered off the Pacific Northwest that will progress eastwards and bring a frontal system into the region. This frontal system will be the initial round of a series of storms that will extend through the seven-day forecast -- more on that in the next section. For this round, high resolution model output shows the main frontal rain band starting to enter the North Bay around the time of the morning commute, extending into the central Bay Area later in the morning into the early afternoon, and passing through the Central Coast in the afternoon hours. Rainfall totals will top out around half an inch to an inch across much of the Bay Area save the far interior East Bay, Santa Cruz County, and the Santa Lucia range. Rain totals in the Santa Clara Valley and the Monterey-Salinas area lie around a third of an inch to an inch while the interior parts of the Central Coast should expect a tenth to a third of an inch. Strong winds are expected to build as the front approaches with sustained winds generally around 15-30 mph and gusts of 30-40 mph across the region. Locally higher gusts to 50 mph are possible at the immediate coast, especially near Monterey Bay and the Big Sur coast, and through favored gaps and passes including the San Bruno Gap, the Altamont Pass, the Carquinez Strait, Bayshore locations along San Pablo Bay, and the Salinas Valley. Another concern will be the risk of thunderstorms embedded within the main rain band and potentially in the post-frontal environment. The cold low will be centered to our north, but will still bring cool enough air aloft to bring the MUCAPE values up to 100-300 J/kg. That would be within the top 10% of soundings at Oakland for practically any time of year. There is also strong shear aloft enhanced by the region coming within the left exit region of a jet streak visible at the 500 mb level, where the decelerating winds and vertical circulation support an area of upper level divergence, which would support convective activity in the area. A slight (15%) chance of thunder has been added to the SF Bay Area for this morning and afternoon as a result. K-Index values from the European model top out around 30 degrees C, which would support isolated thunderstorms.
Behind the main front, the rain becomes showery and winds will diminish and turn towards the west and northwest. Highs today will be remarkably cooler than yesterday's with the lower elevations seeing highs in the upper 50s to lower 60s while the higher elevations of eastern Santa Clara County and the Central Coast drop into the lower to middle 50s.
Hazardous beach conditions are forecast for the Pacific coast through the evening with dangerous conditions expected to develop into Saturday. A Beach Hazards Statement is currently in effect for the Pacific coast for breaking waves 15 to 20 feet along with an increased risk of sneaker waves and rip currents, while High Surf Warnings will go into effect 6 PM tonight into early Sunday morning due to surf heights of 25 to 35 feet accompanied by a high risk of sneaker waves and rip currents. In addition, coastal flooding concerns due to high tides persist at the bayshore locations along San Pablo, San Francisco, and southern Monterey Bays through the high tide cycle today, along with coastal flooding along the Pacific coast due to wave runup impacts on Saturday. See the BEACHES section for more details.
..issued at 1200 AM PST Fri Nov 13 2026 (Saturday through Thursday)
Saturday will feature a lull in the rain with some lingering post- frontal showers in the morning, as highs reach the lower to middle 60s across the lower elevations. Then, a second frontal system comes through Sunday into the early part of Monday. At this time, it looks like the rainfall totals will be similar to Friday's system with generally beneficial effects. Another lull in the rainfall comes later Monday into Tuesday, before a third system comes into the region later on Tuesday through Wednesday and Thursday. It's a little too early at this stage to be confident on how much rain this third system will bring.
As we go through the week, the main point to watch will be soil saturation across the region. The initial rounds of rain will be generally beneficial, reducing our fire weather threat and recharging the snowpack across the Sierra Nevada. Flooding concerns will be minimal with nuisance flooding possible across urban areas and small streams. Outside of these areas, rainwater is absorbed into the ground, which at this time, remains rather dry. As the rain continues to arrive, local soils saturate and are no longer able to hold as much additional rainfall, thus diverting excess water onto the surface and streams and rivers. Wet soils will also increase the chance for shallow landslides across the Bay Area, leading to further damage to homes and properties. Beyond the seven-day outlook, the pattern remains active with a lean towards rainfall totals above the seasonal average through late November. We will need to monitor what this will mean for soil saturation and the possibility for landslides through the next week.
(18z TAFS) Issued at 946 AM PST Fri Nov 13 2026
Dynamic day across all terminals with impacts likely. ATTM a cold front is knocking on the door step. Steadier rain is beginning to develop over the N and then will spread across the big 3 19-21Z timeframe. Heavier rain will drop CATs to IFR. Expect IFR with the frontal passage, but looking upstream behind the front some clear is expected with MVFR to VFR CATs. In addition to rain and lower CIGs winds will be strong and gusty ahead of and during the fropa. AWW remains in effect for SFO. Tonight will transition to widely scattered showers and decreasing winds.
Vicinity of SFO, Delayed timing by an hour or so from 12Z taf. Heaviest precip is now on track for 19-21Z timeframe. Do expect a wind shift this afternoon behind the front. Winds will taper off after 00Z.
SFO Bridge Approach, Similar to SFO.
Monterey Bay Terminals, VFR and breezy until later this afternoon. Drainage/terrain flow will chance winds for SNS through this afternoon.
(today through Wednesday) Issued at 854 AM PST Fri Nov 13 2026
Dangerous conditions will exist over the coastal waters today due to strong to gale winds as a cold front sweeps through. The front will also bring a chance for thunderstorms to the waters north of the Golden Gate. Rough to very rough seas will develop today as a large swell builds. Winds will diminish tonight and Saturday with high pressure temporarily building in across the coastal waters and bays. Southerly winds will become gusty on Sunday ahead of the next cold front. Significant wave heights will build up to 25 feet by Saturday. Wave heights will decrease slightly by Sunday before increasing on Monday.
Issued at 1200 AM PST Fri Nov 13 2026
Beach Hazards Statement/High Surf Warning:
A Beach Hazards Statement is in effect through 6 PM tonight, at which point it gets replaced with a High Surf Warning through 4 AM Sunday. A series of hurricane force low pressure systems will impact the NE Pacific through early next week. These storms will produce very high NW swell that will impact the coast with very hazardous conditions. Initially the forerunners will bring strong rip currents and sneaker waves through the day, while the breaking wave amplitude builds to 15- 20 feet. As the peak of the swell arrives on Saturday, breaking waves will reach up to 35 feet. Occasional sets of 40-50 ft are likely at favored breakpoints. These waves bring tremendous power that will overpower anyone in the water and cause coastal erosion. The risk of drowning is very high this weekend. Do not go in the water, avoid climbing on the rocks or leaning over seawalls, and never turn your back on the ocean. Wave amplitude will abate somewhat on Sunday before a new round of very high swell arrives Monday.
Coastal Flood Advisory (Today):
A combination of high astronomical tides and thermal expansion from warmer than normal water will result in tidal flooding concerns across Bayshore locations in the San Francisco, San Pablo, and Monterey Bays. At the San Francisco tide gauge, high tide is expected to be 1.5 ft above normal (7.3 ft MLLW) at 12:49 PM Friday 11/13. These predictions include up to 1.8 ft of surge that will enhance the astronomical tide and flooding threat. High tide varies up to 90 minutes earlier or later along the Pacific Coast and through the San Francisco Bay, respectively. In addition, long- period swell will create hazardous conditions along the Pacific coast beaches with an increased risk of sneaker waves and rip currents.
Coastal Flood Advisory (Saturday):
The swell on Saturday brings a different variety of coastal flooding as very large breaking waves pile up along the Pacific coast. Research shows wave run-up increases the mean water level by 10-20% of the breaking wave height across exposed beaches. This higher water elevation sets the stage for large waves to crash over sea walls and run up beaches onto adjacent infrastructure, particularly during high tide.
Ca, Beach Hazards Statement until 6 PM PST this evening for CAZ006- 505-509-529-530.
Coastal Flood Advisory until 4 PM PST this afternoon for CAZ006- 506-508-530.
Coastal Flood Advisory from midnight tonight to 6 PM PST Saturday for CAZ006-505-509-529-530.
High Surf Warning from 6 PM this evening to 4 AM PST Sunday for CAZ006-505-509-529-530.
PZ, Gale Warning until 3 PM PST this afternoon for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm- SF Bay N of Bay Bridge.
Gale Warning until noon PST today for Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM.
