Technical NOAA Weather Discussion

FXUS66 KMTR 240720
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1220 AM PDT Wed Jun 24 2026

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

.KEY MESSAGES...
Updated at 1215 AM PDT Wed Jun 24 2026

 - Hazardous beach conditions along the Pacific Coast through 
   Wednesday

 - Warming peaks Wednesday with Minor HeatRisk

 - An upper trough settles over the West Coast by late week, 
   bringing cooler temperatures and breezy to gusty winds

&&

.SHORT TERM...
Updated at 1215 AM PDT Wed Jun 24 2026
(Today through Thursday)

The marine layer remains roughly 1000 to 1500 ft with stratus 
building back inland early this morning, although slightly less 
inland push than yesterday morning.

The marine layer will continue to slowly compress through the short 
term with a slow reduction in stratus, along with warmer and dry
conditions continuing. The more compressed marine layer will 
allow patchy fog to develop along the coast and in wind-sheltered 
valleys this morning and again tonight/Thursday morning.

Subtle ridging will allow for temperatures to peak this 
afternoon. Highs will climb into the 80s for inland areas, while 
far interior areas will reach the 90s. Continued cooler along with
coast with highs in the upper 50s to lower 60s, with 70s for 
near-coast areas. An upper-level trough will begin to build over 
the western US by Thursday as a large upper-level low drop south 
along the Canadian coastline. Temperatures will still be similar 
to Wednesday, with a few spots seeing their afternoon highs 
slightly lower than Wednesday, mainly south of the Bay Area.

The other primary concern remains the long-period southerly swell 
impacting the Pacific Coast beaches into Wednesday afternoon. There 
is a high risk for sneaker waves and strong rip currents...never 
turn your back to the ocean. Additional information can be found in 
the Beach Hazard Statement and the Beaches discussion section
below.

&&

.LONG TERM...
Updated at 1215 AM PDT Wed Jun 24 2026
(Thursday night through next Tuesday)

The cooling trend will become more pronounced Friday into Saturday 
as a large upper-level low pushes into the PacNW and upper-level 
troughing deepens over the region, leading to a resurgence of the 
marine layer and much cooler temperatures. Temps will be roughly 
4-8 degrees cooler Friday as compared to Thursday for inland 
spots with highs along and near the coast in the 60s and inland
areas in the 70s to low 80s. Further cooling continues into 
Saturday as heights to fall with the approach of the low. By 
Saturday morning, the marine layer will be deep enough to support 
patchy drizzle, primarily for the coastal areas. A slight warming
trend is still favored for Sunday into early next week, but 
overall confidence is still low as some long-range models keep a 
prevailing troughing pattern lingering over the West that may 
limit warming into early next week, but temperatures should 
improve a bit as compared to the Friday/Saturday cooldown.

Onshore winds will begin to increase on Thursday as the low
approaches and gradient tightens, peaking Friday and Saturday 
with a frontal passage. Expects gusts of 25 to 35 mph. Gusts may 
exceed 40 mph at times, especially for wind-prone areas and 
mountain passes. Winds should subside Sunday into early next week
with the gradient relaxes as the low departs.

&&

.AVIATION...
(06Z TAFS)
Issued at 903 PM PDT Tue Jun 23 2026

It's VFR except for stratus /MVFR-IFR/ along the immediate 
coastline. Stratus /MVFR-IFR/ moves inland tonight and Wednesday 
morning. Stratus mixes out to the coastline with conditions 
improving to MVFR-VFR by late Wednesday morning and afternoon. 
Coastal stratus redevelops Wednesday night and Thursday morning.

Vicinity of SFO...Stratus /MVFR-IFR/ prevails tonight and 
Wednesday morning with mix out to VFR 19z Wednesday. Stratus
/MVFR-IFR/ returns Wednesday evening. West to northwest wind 5 to
12 knots tonight then increasing to near 15 knots beginning 19z 
Wednesday, then easing to 5 to 10 knots late Wednesday evening.

SFO Bridge Approach...Similar to SFO.

Vicinity of SJC and OAK...For SJC Airport VFR for the evening, 
then stratus /MVFR/ develops overnight then mixes out to VFR 17z 
Wednesday. Northwest wind 5 to 10 knots decreasing to light and 
variable wind early Wednesday morning then northwest near 15 knots
Wednesday afternoon. For OAK Airport stratus /MVFR-IFR/ prevails 
tonight and Wednesday morning, mixing out to VFR 19z. Stratus
/MVFR-IFR/ returns Wednesday evening. West wind 5 to 15 knots.

Monterey Bay Terminals...Stratus /MVFR-IFR/ moves inland tonight
and Wednesday morning. Conditions improving to MVFR-VFR late 
Wednesday morning and afternoon. Stratus /MVFR-IFR/ returns 
Wednesday evening and night. Onshore winds 5 to 15 knots.

&&

.MARINE...
(Tonight through next Monday)
Issued at 830 PM PDT Tue Jun 23 2026

Gentle to moderate winds will persist through midday Wednesday
with generally moderate seas. Fresh to strong breezes and rough
seas are forecast to resume over the coastal waters late in the
week. Hazardous conditions for small craft will develop Wednesday
afternoon and continue through at least Thursday for the northern
outer waters. Long period southwest swell will persist through
the extended forecast.

&&

.BEACHES...
Updated at 1215 AM PDT Wed Jun 24 2026

Long period southerly swell at around 16 to 18 seconds emanating
from energetic storms in the Southern Hemisphere continue to 
affect the California coast, 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. A 
Beach Hazards Statement for Pacific Coast beaches continues 
through Wednesday afternoon. Be sure to 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!

The southerly swell is expected to subside tonight into the 
latter half of the work week before increasing again by the 
weekend.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through Wednesday afternoon for CAZ006-
     505-509-529-530.

PZ...Small Craft Advisory from 3 PM Wednesday to 3 AM PDT Thursday 
     for Pt Arena to Pt Reyes 10-60 NM.

&&

$$

SHORT TERM...Slagle
LONG TERM....Slagle
AVIATION...Canepa
MARINE...Canepa

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Prepared by Boulder-Creek.com Weather at: Wed Jun 24 02:30:03 PDT 2026
From the National Weather Service