textproduct: San Francisco Bay Area

KEY MESSAGES

Updated at 1218 AM PDT Tue May 5 2026

- Cool temperatures and cloudy with light rain ending this morning

- Warmer and drier conditions return for the middle of the week through the weekend

SHORT TERM

Issued at 504 PM PDT Tue May 5 2026 (This evening through Thursday)

Some isolated light rain has produced a few hundredths of an inch of rainfall for some elevated interior portions of the East Bay and South Bay, with drier air filling in behind the exiting system to the east early this afternoon. Expect a mix of sun and clouds through the remainder of the day and early evening. A robust marine layer will fill in across much of our area overnight, with rapid clearing by late morning into early afternoon Wednesday, as the ridging pattern takes hold. Temperatures Wednesday will increase around 5-10 degrees higher than todays values.

LONG TERM

Issued at 504 PM PDT Tue May 5 2026 (Thursday night through next Tuesday)

Confidence is high in ridging maintaining its hold on our synoptic pattern through the extended forecast and beyond. The warmup that sets in tomorrow is gradual through the remainder of the work week, with a more notable increase this upcoming weekend. As the ridge becomes more prominent by the end of the week we'll see the marine layer retreat back closer to the coast and compress, but not all the way offshore. Ensemble clusters are relatively tightly packed through mid-May wrt the ridging pattern and above normal temperatures. Our entire area is currently in Minor HeatRisk on Saturday with portions of our interior in Moderate HeatRisk Sunday and Monday. That trend should persist past the current forecast period as well. However, there are hints for some relief in the same ensemble clusters with troughing in the E Pacific at our latitude headed into the 3rd week of May.

AVIATION

(00Z TAFS) Issued at 504 PM PDT Tue May 5 2026

Moisture wrapping around the backside of the departing upper low has kept widespread strato-cu over the terminals. CIGs range from 3-4k ft. Current thinking is strato-cu will fade as the sun sets and marine layer stratus will form...there could be a brief period where some SCT occurs. The developed stratus will last through Wednesday mid to late morning.

Vicinity of SFO...VFR CIGs with MVRF CIGs developing this evening and lasting into the AM rush.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR CIGs with MVRF CIGs developing this evening and lasting into Wednesday AM.

MARINE

(Today through Sunday) Issued at 957 AM PDT Tue May 5 2026

The gradient between high pressure over the Eastern Pacific and lower pressure over the western United States will support a gentle northwest breeze and moderate seas through Wednesday. This gradient will gradually tighten from Thursday through Saturday, causing winds to increase to a strong breeze and building rough seas for the weekend.

MTR WATCHES/WARNINGS/ADVISORIES

CA...None. PZ...None.