textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 101 PM PDT Tue Jul 14 2026

- Moderate HeatRisk continues across the interior Wednesday

- Breezy onshore winds through Thursday

- Elevated fire weather conditions through Thursday

SHORT TERM

Issued at 1139 PM PDT Tue Jul 14 2026 (Tonight through Thursday)

It was hot Tuesday. San Francisco hit 76, Santa Rosa 97, Livermore 102, and San Jose 95. I made the mistake of baking bread in the afternoon and my house in Monterey got to 81 degrees. The highs were about 5 degrees warmer than forecast, driven by strong high pressure to the east and totally clear skies. The 03Z WPC Surface Analysis shows a mesoscale 1019 mb high over northern Nevada that was stronger than expected. The 6-member PGE WRF ensemble (POMMS EPS) predicted the SFO-WMC gradient would be between +3 and +4 mb at 04Z, and it was actually observed at -3.8 mb. In other words the weather models missed this mesoscale high pressure over Nevada. This helped keep the air dry today and discouraged the marine layer from reforming. Temperatures are going to remain relatively warm overnight, but not quite as warm as last night thanks to the clear skies and enhanced radiational cooling. Similar high temperatures are expected Wednesday afternoon with slightly stronger winds in the afternoon as a trough starts to approach the coast. The overnight temperatures will cool much more effectively Wednesday night.

With the hot temperatures, low humidity, and moderate onshore winds, fire weather conditions will be elevated Wednesday and Thursday. A few stations are currently reporting red flag conditions across the North and East Bay. This will continue over the next couple days. Wednesday is hot and dry with moderate winds. Thursday will be a little cooler, but the winds will be a bit stronger. The elevated fire weather will continue through the nights as well. The lack of marine layer and strong thermal belting will keep higher elevations warm with poor humidity recoveries.

LONG TERM

Issued at 1139 PM PDT Tue Jul 14 2026 (Thursday night through next Tuesday)

A cooling trend starts Thursday as a low pressure trough approaches the coast. There has been a slight change from yesterday however. It now looks like the Rocky Mountain 500 mb high will remain strong enough to force the incoming low north into the Pacific Northwest. The associated trough will still bring us cooler temperatures, but maybe not as drastic or quick as we thought yesterday. Temperatures will be about 5 degrees above normal Thursday, near normal Friday, and 5 degrees cooler than normal over the weekend and into early next week. The marine layer will also start to reform during this cooling trend, with low clouds likely to return to the typical gloomy areas by Friday morning.

The large scale mid level flow will stay out of the SW between the fairly stationary Eastern Pacific trough and central US ridge. This keeps the conveyer belt open for surges of tropical moisture, particularly if a recurving tropical cyclone drags some of the deep tropical moisture into the subtropics. We now have a tropical cyclone in the NE Pacific near 15N, 110W named TROPICAL DEPRESSION FIVE-E. This system is expected to become a hurricane by Thursday and continue NW through the weekend. Depending on the track and the ultimate strength of this tropical cyclone, it has the potential to bring moisture far enough north to be sucked into the conveyer belt and delivered to the Bay Area. The uncertainty is pretty high with tropical cyclone tracks, but it looks likely that there will be some moisture arriving Sunday or Monday from this system. The amount of moisture is still up in the air. The ECMWF ensemble mean has dropped from 1.0" yesterday to 0.8" today (90th percentile to 75th percentile), but the spread between members remains quite large. Why do we care about this? Elevated moisture surges bring the potential for high based thunderstorms and dry lightning that can spark wildfires.

AVIATION

(06Z TAFS) Issued at 919 PM PDT Tue Jul 14 2026

Satellite shows it's clear across much of the forecast area. KHAF reports MVFR in haze. VFR is forecast except a patch or two of coastal stratus and fog may develop tonight and Wednesday morning.

Vicinity of SFO...VFR. Northwest to west wind 10 to 15 knots tonight and Wednesday morning. West wind increasing to 20 to 25 knots Wednesday afternoon and evening.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR except patchy stratus and fog /LIFR-IFR/ possibly nearby late tonight and Wednesday morning. Winds mainly west to northwest 5 to 15 knots.

MARINE

(Tonight through next Monday) Issued at 916 PM PDT Tue Jul 14 2026

Moderate to fresh northwesterly breezes will strengthen to fresh to strong across the coastal waters this week. This will result in widespread hazardous conditions for small craft.

FIRE WEATHER

Issued at 101 PM PDT Tue Jul 14 2026

The warm temperatures we have had the past several days and continued warm weather has resulted in fuels rapidly drying this week. ERC charts are expected to exceed the 97th percentile across the Mid Coast to Mendocino zone and get close to the 97th percentile across the Central Coast. Fire weather concerns will remain elevated this afternoon through Thursday due to near critically dry conditions, gusty onshore winds, and very dry fuel conditions. This may result in additional fire starts particularly across the interior and higher elevations. Unsettled weather is possible next weekend with returning potential for dry thunderstorms and gusty, erratic winds.

RGass/Flynn

MTR WATCHES/WARNINGS/ADVISORIES

CA...Coastal Flood Advisory until 4 AM PDT Thursday for CAZ006-506- 508.

Coastal Flood Advisory until 4 AM PDT Wednesday for CAZ505-509- 529-530.

Heat Advisory from 10 AM to 10 PM PDT Wednesday for CAZ516-517.

PZ...Small Craft Advisory from 3 PM to 9 PM PDT Wednesday for Mry Bay.

Small Craft Advisory from 9 AM to 3 PM PDT Thursday for Mry Bay- Pigeon Pt to Pt Pinos 0-10 nm.

Small Craft Advisory until 3 PM PDT Thursday for Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM.

Small Craft Advisory from 9 AM Wednesday to 3 PM PDT Thursday for Pt Reyes to Pigeon Pt 0-10 nm.

Small Craft Advisory from 9 AM to 9 PM PDT Wednesday for Pigeon Pt to Pt Pinos 0-10 nm.

Small Craft Advisory until 9 AM PDT Thursday for Pt Pinos to Pt Piedras Blancas 0-10 nm.

Gale Warning from 9 AM to 3 PM PDT Thursday for Pt Pinos to Pt Piedras Blancas 0-10 nm.

Small Craft Advisory from 3 PM Wednesday to 3 PM PDT Thursday for Pigeon Pt to Pt Pinos 10-60 NM.