268
FXUS66 KMTR 050355
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
855 PM PDT Fri Apr 4 2025

...New UPDATE, MARINE...

.SYNOPSIS...
Issued at 1211 PM PDT Fri Apr 4 2025

Early Spring warmth will persist into the weekend with hazardous
beach conditions and light rain expected Sunday into Monday. A
warming trend is expected to resume by the middle of the upcoming
week as a ridge of high pressure builds over the region.

&&

.UPDATE...
Issued at 849 PM PDT Fri Apr 4 2025

Forecast remains on track with no update necessary this evening.
A Beach Hazard Statement was issued this afternoon for the risk of
sneaker waves and riptides Sunday and Monday with long period
northwest swells. We`re really trying to emphasize the messaging
as this coincides with the first real warm up of the new Spring
season, which will naturally draw many people to our coastal
communities. Please read below for more information about the
anticpated minor heat risk and hazardous beach conditions.

&&

.SHORT TERM...
(This evening through Saturday)
Issued at 1211 PM PDT Fri Apr 4 2025

Temperatures this afternoon are forecast to be in the lower 70s
across the interior with upper 50s to 60s near the coast. Mainly
clear sky conditions will prevail as high pressure builds in from
the eastern Pacific. As a result, it will feel noticeably warmer
with minor HeatRisk returning to San Francisco, the San Francisco
Bay Shoreline, the Santa Clara Valley, and the Northern Salinas
Valley.

Tonight, temperatures will fall into the 40s across most of the
region with low clouds expected to return to the coast. However,
widespread inland cloud cover is not expected to persist into
Saturday.

As the high-amplitude ridge continues to build, temperatures
Saturday afternoon will warm by a few degrees to slightly above
seasonal averages (generally around 5 degrees in most locations).
HeatRisk expands slightly in coverage to the North Bay valleys and
around Santa Cruz.

NWS Minor HeatRisk:

- Heat of this type is tolerated by most; however there is a minor
risk for extremely heat-sensitive groups to experience negative heat-
related health effects.

- The risk is primarily for those who are extremely sensitive to
heat, especially when outdoors without effective cooling and/or
adequate hydration.

- Very common heat.

- For those at risk, actions that can be taken: increase hydration,
reduce time spent outdoors or stay in the shade when the sun is
strongest, and open windows at night and use fans to bring cooler
air inside buildings.

&&

.LONG TERM...
(Saturday night through next Thursday)
Issued at 1211 PM PDT Fri Apr 4 2025

The warming trend will continue into Sunday across the Central
Coast, while the North Bay cools slightly ahead of an approaching
frontal boundary. This boundary will result in increased chances for
light rain late Sunday afternoon and into early Monday morning
across the North Bay with little to no measurable rainfall south of
the Golden Gate. Rainfall from Sunday into Monday will range from
about 1/3" in far northwestern Sonoma County to just a few
hundredths to 1/10" in the North Bay valleys.

Zonal flow develops on Monday and Tuesday before a ridge of high
pressure builds is from the south. This will result in temperatures
between 5-15 degrees above average for this time of year by
Wednesday and Thursday. As we remain several days out from this warm-
up, be sure to check back for the latest forecast information as the
forecast evolves.

&&

.AVIATION...
(00Z TAFS)
Issued at 435 PM PDT Fri Apr 4 2025

VFR. Gusty west to northwest winds continue through the evening
before easing overnight. Light winds will be offshore to at times
variable overnight before moderate onshore flow returns during the
day tomorrow. High level clouds build in overnight into tomorrow
with low level CIGs not expected to spread inland. Confidence is low
to moderate that lower CIGs/VIS will impact HAF overnight with
reductions in visibility to around 4SM. Conditions look to be too
dry to support fog at STS and APC overnight but a brief period
between 12Z-16Z may allow for slight reductions in visibility at
STS.

Vicinity of SFO...VFR. Moderate onshore flow with gusts to around 20
knots are expected through late this evening before winds ease
overnight. Moderate west to northwest winds return again during the
afternoon and evening tomorrow.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR. Moderate onshore flow continues
through this evening before winds diminish and shift offshore
overnight. Winds strengthen during the day tomorrow, becoming light
to moderate, and shift west to northwesterly through the end of the
TAF period.

&&

.MARINE...
(Tonight through next Thursday)
Issued at 849 PM PDT Fri Apr 4 2025

A gentle to moderate northwest breeze will continue across the
coastal waters into early Sunday morning. A weak cold front will
move through the waters on Sunday with winds shifting more
southwesterly and light rain possible across the northern waters.
Wave heights build to between 10 to 12 feet Sunday into Monday as
long period moderate swell returns. This will result in increased
shoaling near the coast, bays, and harbor entrances.

&&

.BEACHES...
Issued at 418 AM PDT Fri Apr 4 2025

Still looking at hazardous beach conditions this weekend. A
longer period swell is still on track to reach the coast early
Sunday morning. Forerunners of 18-20 sec arrive around or shortly
before sunrise. Periods are forecast to diminish through the day
Sunday and into Monday, but swell heights will gradually increase.
Therefore, initially sneaker waves will be the main threat before
switching to larger shore break and rip currents. A Beach hazard
statement will likely be needed to cover the threat. Beachgoers
should be mindful Sunday and Monday given potential hazards.
Beachgoers should stay off of jetties and rocks, keep pets on a
leash, wear a life jacket, and never turn your back on the ocean!

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement from Sunday morning through Monday
     evening for CAZ006-505-509-529-530.

PZ...None.
&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...JM
MARINE...Kennedy

Visit us at www.weather.gov/sanfrancisco

Follow us on Facebook, X, and YouTube at:
www.facebook.com/nwsbayarea
x.com/nwsbayarea
www.youtube.com/nwsbayarea