Technical NOAA Weather Discussion

FXUS66 KMTR 291957
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1257 PM PDT Wed Apr 29 2026

...New SHORT TERM, LONG TERM...

.KEY MESSAGES...
Updated at 1256 PM PDT Wed Apr 29 2026

 - Warming and drying trend continues into Friday for areas away 
   from the coast

 - Overnight and early morning stratus remains in the forecast as
   the marine layer deepens this weekend

 - Cooler conditions return this weekend with a chance of drizzle
   and/or light rain into early next week 

&&

.SHORT TERM...
Issued at 1256 PM PDT Wed Apr 29 2026
(This evening through Thursday)

The warming trend continues this afternoon with high pressure 
building in from the eastern Pacific Ocean. This afternoon will warm 
into the upper 50s to low 70s near the coast and mid 70s to near 80 
degrees F across the interior under mostly clear sky conditions.

Expecting low clouds to return to the coast and locally inland into 
the coastal adjacent valleys overnight tonight and more so into 
Thursday morning. This is especially so over the Monterey Bay Region, 
the San Francisco Peninsula, and through the Golden Gate into 
Oakland. There is a greater probability of this to occur as the 
marine layer is forecast to deepen overnight to around 1,200 feet. 
Overnight lows are forecast to range from the mid 40s (colder 
interior locations) to lower 50s. 

Thursday will feature a few degrees of warming across the interior 
(up to 6 degrees F above seasonal averages). However, coastal 
locations will remain will generally remain within a few degrees of 
normal for late April due in large part to onshore flow and the 
marine influence. 

&&

.LONG TERM...
Issued at 1256 PM PDT Wed Apr 29 2026
(Thursday night through next Tuesday)

Temperatures will be warmest Friday afternoon when we have the 
greatest probability of reaching or exceeding 85 deg F across the 
interior, with the warmest being across the interior Central Coast 
(greater than 50%). Temperatures near the coast will remain cooler 
thanks to onshore flow, coastal stratus, and the marine influence. 

A slight downward trend is expected for Saturday as a mid/upper 
level trough drops down from the Gulf of Alaska and into the eastern 
Pacific. This will help deepen the marine layer to around 2,000 
feet. Thus, expect coastal stratus to penetrate deeper into the 
valleys on both Saturday and Sunday. This low pressure system will 
eventually become a cut-off low with high pressure building across 
British Columbia late in the weekend setting up a Rex block. This 
would bring drizzle and/or light rain to the coastal waters Saturday 
night and into Sunday. Then, as the mid/upper level low shifts 
inland Monday and Tuesday, it will bring increasing chances for 
drizzle and/or light rain to the Bay Area and Central Coast. The WPC 
500 mb height-based cluster analysis shows increasing confidence in 
this pattern occuring. Rainfall amounts from this system are 
expected to remain very light, with generally a few hundredths of an 
inch expected throughout this early week event. 

&&

.AVIATION...
(18Z TAFS)
Issued at 1050 AM PDT Wed Apr 29 2026

The patchy fog has cleared and low clouds have pulled back to the 
coast. There's high confidence in VFR conditions across all 
terminals this afternoon, with the exception of HAF. While we expect 
several hours of VFR conditions there, the stratus deck is 
expected to hang around just off the coast and could make a surge 
at any time. Winds will increase to a moderate onshore breeze with
the arrival of the sea breeze this afternoon. Low clouds are 
likely to return overnight as the marine layer continues to become
better organized. While we expect a fully formed marine layer by 
Friday morning, we're still in the transition Thursday morning and
the impacts will be more scattered and temporary. As such, the 
forecast confidence is rather low through the second half of the 
TAF period.

Vicinity of SFO...VFR conditions through the afternoon and
evening. Winds will shift to westerly and increase to a strong 
breeze over the next few hours. There is a 50-70% chance of MVFR 
stratus impacts Thursday morning, with the highest likelihood 
around 15Z. The window of likely impacts is only around 4-6 hours,
however, and there's a chance the terminal dodges these ceilings.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...There's high confidence in VFR conditions
through the afternoon. The chance for MVFR impacts steadily
increases from 40% at 06Z to 80% by 14Z. If they form, there a 
50% chance these ceilings will drop into the IFR category, at
least temporarily.

&&

.MARINE...
(Today through Monday)
Issued at 1050 AM PDT Wed Apr 29 2026

NW winds will increase to a strong breeze this afternoon. These
winds will build rough seas of 8 to 12 feet. Similar conditions
will persist through Friday before winds start to decrease
Saturday and continue improving through the weekend.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT Thursday for Pigeon Pt to Pt 
     Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm.

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

     Small Craft Advisory until 9 PM PDT Thursday for Pigeon Pt to Pt 
     Pinos 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory until 9 PM PDT Thursday for Pt Arena to Pt 
     Reyes 10-60 NM.

&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Flynn
MARINE...Flynn

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Prepared by Boulder-Creek.com Weather at: Wed Apr 29 14:30:03 PDT 2026
From the National Weather Service