textproduct: San Francisco Bay Area

KEY MESSAGES

Issued at 100 PM PDT Wed Jun 10 2026

- Hot and dry through Saturday with a moderate risk of heat- related illnesses for interior locations Thursday and Friday.

- Critical fire weather threat for the interior North Bay and the East Bay Mountains late tonight into Thursday morning with critically dry conditions persisting into Thursday afternoon.

- Increased risk of sneaker waves and strong rip currents along south and southwest facing beaches through the weekend.

- Minor coastal flooding due to higher than normal high tides anticipated across coastal regions of the San Francisco Bay area this weekend.

SHORT TERM

Issued at 100 PM PDT Wed Jun 10 2026 (This afternoon through Thursday)

Our well advertised warm up is in full swing today with afternoon temperatures already climbing into the 70s and 90s. With clear skies and a dry airmass interior valley regions will experience mid to upper 90 degree heat this afternoon.

Tonight, more impactful weather is anticipated to take shape as a diffuse trough swings through Big Sky Country into the northern high plains. In the wake of this feature, 3 hour 5-7 mb surface pressure rises across the Great Basin will tighten the low level height/surface pressure gradient between building high pressure and the coastal trough. Subsequently the wind field is anticipated to respond with the latest NWP remaining consistent with a 30-40 knot 925mb jet extending from the northern Sac Valley down into the delta. Lower elevations/valleys will likely see the planetary boundary layer decouple from the free atmosphere and as a result, I'm not anticipating overly gusty winds in the population centers.

For locations at elevation (above 1500 feet), boundary layer decoupling is unlikely and this will be two fold. Firstly, temperatures will remain elevated and overnight humidity recovery will be poor (RH values likely not climbing above 40%). Secondly, the aforementioned momentum at 925mb will be transfered down to the surface (again at elevations at or above 1500 feet). This should translate to frequent gusts above 30 to 35 mph. Cross- sections from the 2km SJSU/PG&E WRF advertise tightly packed isentropes or lines of potential temperature downwind of higher terrain features such as Mt. Saint Helena. This implies a potential for mountain wave type activity as well as a greater threat for wind gusts in excess of 60 mph. Fuels intelligence reveals that grasses (more of the 1 and 10 hour or fine fuels) are largely cured and with the combination of the forecast winds and RH, a critical fire weather threat is anticipated to materialize. A Red Flag Warning is in effect to capture the most likely time period for these conditions described above from 11pm tonight into 9am Thursday across the North Bay Interior Mountains and East Bay Hills. Individuals should obey any fire restrictions/burn bans, extinguish any camp fires, secure tow chains trailers/RVs, and NEVER toss cigarette butts out the window. Remember, one less spark, one less wildfire. While winds will abate after sunrise Thursday, RH will remain critically dry, especially interior portions of the Bay Area and Central Coast. While winds remain below threshold, it's important for people to remain vigilant and avoid activities that could spark a wildfire.

The burst of offshore winds will keep the marine layer at bay (no pun intended) and result in a dry airmass. Both will promote a sharp diurnal temperature curve. With sunny skies and virtually non-existent onshore flow (except maybe at the immediate coastline). Thursday high temperatures are anticipated to soar 15 to 25 degrees above normal with widespread mid to upper 90s. Some locations may even exceed the century mark, especially across far interior valleys of the North Bay, East Bay, and South Bay. A handful of our climate sites may also flirt with or exceed daily record highs for June 11th. With the probability of moderate HeatRisk at or above 95% for these locales, a Heat Advisory is in effect for Thursday (and parts of the area on Friday). Heat of this caliber affects most individuals sensitive to heat, especially those without effective cooling and/or adequate hydration. Some impacts can be expected to health systems and in heat-sensitive industries. Be sure to hydrate with plenty of water and check on those vulnerable groups that are sensitive to heat (elderly and young). Never leave pets or children unattended in vehicles! Do your best to limit strenuous outdoor activity during peak heating. If headed to the coast, be sure to be mindful of the increased risk for sneaker waves and rip currents! More details in the beaches section below.

LONG TERM

Issued at 100 PM PDT Wed Jun 10 2026 (Thursday night through next Tuesday)

Thursday Night - Friday morning lows may cool some, with the exception being across some of the higher terrain where the thermal belt may remain somewhat active. Offshore winds are not expected to be quite as stout, however.

Uncertainty in the MaxT forecast persist on Friday. With the upper trough responsible for driving the offshore winds moving farther east, the low level height/pressure gradient should ease. In fact, a very diffuse front/trough will approach from the north and try to encourage some onshore flow. The diffuse nature of this boundary, however, means that the wind field may not be overly impressive. While some high-resoultion NWP does indicate onshore flow, magnitudes are on the lighter side with speeds of 5 to 10 knots, though terrain enhancements may result in some accelerations across the coastal range. I would anticipate a more structured sea-breeze push on Friday afternoon and areas across the North Bay may experience a very weak frontal passage. Farther east and south, however, very little in the way of onshore flow may transpire. Probability of Moderate HeatRisk remains at or above 80% for interior sections of the East Bay and South Bay and as a result, we've extended the Heat Advisory for an additional day (Friday here). I wouldn't discount the need for at least continued heat messaging into the weekend, however, more diurnal offshore/onshore flow is anticipated which may give more areas relief from the heat. Afternoon conditions will likely remain very pleasant and as noted above, be mindful if headed to the beach as the sneaker wave threat will continue. In addition, higher than normal high tides (1 to 1.5 feet above normal) are advertised through June 15th. As a result, extension of the Coastal Flood Advisory is probable in subsequent shifts.

Morning fog/drizzle may need to be added as we get a little closer to the weekend. Ridging is expected across the Pacific Northwest into British Columbia through next week. There's some degree of broad troughing that is advertised in the ensemble means. Given the orientation of this upper trough (positively titled), we cannot discount a few more burst of offshore winds. Deterministic NBM guidance does appear to support this with a warming trend advertised for next week.

AVIATION

(12Z TAFS) Issued at 457 AM PDT Wed Jun 10 2026

Strong high pressure remains over the forecast area. The ACV-SFO pressure gradient is 8.5 mb and SFO-SAC is 1.8 mb. Gusty northwest winds over the coastal waters are stirring up sea spray aerosols resulting in mist/fog/haze/hazy conditions beneath a shallow marine layer temperature inversion. Sea spray aerosols are condensation nuclei for stratus and fog. Satellite shows a patch of low stratus and fog /LIFR-IFR/ has developed near KMRY otherwise it's VFR across the forecast area. Patches of stratus and fog will mix out during the morning under increasing diurnal warming and mixing. Increasing north-northeast winds in the lower levels develop tonight and Thursday morning resulting in areas of low level wind shear.

Vicinity of SFO...VFR. Wind variable 5 knots becoming west 15 knots in the afternoon and evening. Northeast surface wind 5 knots tonight and Thursday morning. Low level wind shear develops tonight and Thursday morning.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR except for temporary BKN-OVC stratus and fog /LIFR-IFR/ vicinity KMRY early this morning. Variable winds 5 knots becoming west-northwest 5 to 15 knots today. Light and variable winds tonight and Thursday morning.

MARINE

(Today through Monday) Issued at 1142 AM PDT Wed Jun 10 2026

Gale force gusts will continue across the northern waters, with gusty northwest winds continuing across the rest of the waters, resulting in hazardous conditions for small craft. Winds and seas begin to ease by Thursday evening and are expected to stay light through the remainder of the forecast period.

FIRE WEATHER

Issued at 100 PM PDT Wed Jun 10 2026

Increasing northerly 20 foot winds of 10 to 20 mph with gusts to 45 mph are forecast late tonight into Thursday morning. With energy release components trending above the 85th percentile and overnight humidity recovery anticipated to be below 40 percent, a critical fire weather threat is expected to unfold. The threat will be greatest across the North Bay Interior Mountains and East Bay Hills. Pending ignitions, extreme fire behavior and/or spread is likely during the overnight hours into Thursday morning. Winds will subside after 9am Thursday, however, afternoon humidity values in the teens to near single digits are forecast across interior regions. Minimal shading will help to cure fuels further in the afternoon and while wind speeds are largely anticipated to fall below 10 mph, fire spread will remain a possibility, particularly in areas with the favorable alignment of weather, fuels, and topography.

BEACHES

Issued at 100 PM PDT Wed Jun 10 2026

Long period swell will continue, likely during the weekend, 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. Be sure 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!

CLIMATE

Issued at 1235 AM PDT Wed Jun 10 2026

The following are the record highs for June 11th.

Station Record Highs June 11th

Santa Rosa 100 in 2019 San Rafael 97 in 1985 Napa 102 in 2019 Livermore 105 in 1985 San Francisco 92 in 2019, 1877 SFO Airport 98 in 2019 Redwood City 102 in 2019 Oakland Museum 99 in 2019 Half Moon Bay 85 in 2019 San Jose 99 in 2019 Monterey Airport 92 in 2019 Salinas Airport 104 in 2019

MTR WATCHES/WARNINGS/ADVISORIES

CA...Coastal Flood Advisory from 7 PM Thursday to 1 AM PDT Saturday for CAZ006-508.

Heat Advisory from noon to 11 PM PDT Thursday for CAZ503-504-506- 508.

Red Flag Warning from 11 PM this evening to 9 AM PDT Thursday for CAZ504-515.

Beach Hazards Statement through late tonight for CAZ505-509-529.

Coastal Flood Advisory from 6 PM this evening to 1 AM PDT Saturday for CAZ506.

Heat Advisory from noon Thursday to 7 PM PDT Friday for CAZ510- 513>515.

PZ...Gale Warning until 9 PM PDT this evening for Pt Arena to Pt Reyes 0-10 nm.

Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt to Pt Pinos 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

Small Craft Advisory until 3 AM PDT Thursday for Pt Pinos to Pt Piedras Blancas 0-10 nm.

Gale Warning until 3 AM PDT Friday for Pt Arena to Pt Reyes 10- 60 NM.

Small Craft Advisory until 9 AM PDT Thursday for Pigeon Pt to Pt Pinos 10-60 NM.