textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 1201 AM PDT Thu Apr 23 2026

- Seasonal temperatures and dry conditions return today

- Potential for rain/drizzle and slightly cooler temperatures this weekend into early next week

- Warming trend begins early to mid next week

SHORT TERM

Issued at 1201 AM PDT Thu Apr 23 2026 (Today and tonight)

KMUX has been allowed to transition back into clear air mode as shower activity has ended across the region. Relatively moist conditions and light winds overnight will lead to some potential for patchy fog to develop across the valleys. Latest HRRR guidance supports a slightly higher chance for patchy fog to develop within the Santa Clara Valley and potentially within North Bay Valleys. Fog development would be most likely in the early morning hours/right around sunrise. As this may run into the early morning commute, if you encounter fog remember to slow down and allow extra time to reach your destination.

Morning temperatures will be seasonable with lows generally in the 40s. Portions of the Eastern Santa Clara hills, the Gabilan Range, and the Santa Lucia Range will drop into the mid to upper 30s. High temperatures warm up well, however, as a weak, progressive ridge moves through southern and central California. High temperatures will be in the low to mid 70s across the interior and 50s to 60s along the coastline. Temperatures across the lower elevations will be seasonal to seasonally warm while temperatures across the higher terrain are below normal. No other concerns in the short term as dry weather prevails. Winds remain light and onshore today with diurnally breezy conditions expected across the valleys.

LONG TERM

Issued at 1201 AM PDT Thu Apr 23 2026 (Friday through Wednesday)

By Friday, the upper level ridge will begin its eastward exit and weak upper level troughing will return over the Western US. This trough is associated with a deep upper level low that will remain situated over Montana/the Dakotas through the weekend before exiting the region early next week. As weak troughing returns, it will allow a much cooler airmass to filter in over the West Coast Saturday through early next week. Initial guidance shows 850 mb temperatures running between 2-4 degrees Celsius which is between the 10th to 25th percentiles for 850mb temperatures recorded by OAK. For comparison the daily mean 850 mb temperatures are closer to 7 to 8 degrees Celsius. What does that look like at the surface? High temperatures on Friday will be fairly seasonal in the upper 60s to low 70s across the interior and 50s to 60s along the coast. Saturday temperatures will cool by around 5 degrees across the interior where widespread 60s are expected (coastal temperatures remain in the 50s to 60s). We can expect similar temperatures on Sunday before a slight warming trend kicks off Monday as 850mb temperatures warm (becoming more seasonal). This warming trend will see temperatures returning to the low to mid 70s across the interior with temperatures warming by a few degrees each day through the remainder of the long term forecast. Overnight low temperatures remain seasonable through the extended forecast with slightly cooler temperatures expected across the higher elevations of the eastern Santa Clara Hills, the Gabilan Range, and the Santa Lucia Range.

Another factor to consider in planning your weekend is the possibility of rain. Currently, it is looking like we might get some light rain but it will not be as impressive as the system we just had. Ensemble guidance is alternating between drizzle to a few tenths of an inch (0.1-0.2") possible. The higher chances for light rain are across the Central Coast with more drizzly conditions likely across the Bay Area. Higher precipitation totals (compared to us) are more likely across Southern California where the main moisture plume is oriented against. Either way, it is likely to be a drizzly weekend but the incoming rain will be light and beneficial. Ensembles are hinting at additional light, beneficial rain being possible mid to late next week as the upper level pattern remains unsettled.

AVIATION

(06Z TAFS) Issued at 1020 PM PDT Wed Apr 22 2026

The drying trend continues for the 06Z TAFs. Light winds persist overnight and into the early morning hours. Winds increase during the day becoming moderate. Some high clouds will move over the area late morning Thursday. An intrusion of low-level CIGs will move onshore Thursday night as winds reduce. KHAF will be the first to be impacted which is then followed by KOAK and KSFO resulting in MVFR conditions towards the end of the TAF period. All other sites will be VFR.

Vicinity of SFO...Westerly winds are forecast for the majority of the TAF period with a brief period of northerly winds in the late morning on Thursday. By the early afternoon, the winds will shift west again while becoming moderate and gusty through the night. Mainly VFR this TAF period up until 11Z Friday when CIGs lower to MVFR conditions.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR through the TAF period. Winds are becoming light and variable and cloud cover has mostly cleared. Low clouds look to form on the mountain tops in the area overnight, but don't look to affect the TAF sites. Those clouds erode into the early morning with moderate west to northwest winds affecting the region into the late morning. These last into the early night before reducing.

MARINE

(Tonight through next Tuesday) Issued at 1020 PM PDT Wed Apr 22 2026

Showers have dissipated leading to calmer and clearing conditions. A moderate north breeze will develop into a fresh northwest breeze by Thursday afternoon. Wind and seas will begin to gradually subside on Friday, continuing into the weekend.

MTR WATCHES/WARNINGS/ADVISORIES

CA...None. PZ...Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this evening for Pigeon Pt to Pt Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

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

Small Craft Advisory from 3 PM this afternoon to 3 AM PDT Friday for Pigeon Pt to Pt Pinos 10-60 NM.