Alviso, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

129
FXUS66 KMTR 262057
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
157 PM PDT Thu Jun 26 2025

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

.SYNOPSIS...
Issued at 157 PM PDT Thu Jun 26 2025

An inland warming trend Friday and Saturday as high pressure
builds and the marine layer compresses. By Sunday a weak low off
the coast will bring stronger onshore flow and deepen the marine
layer. The low will keep temperatures on the cool side of normal,
especially inland with a continued marine layer along the coast.

&&

.SHORT TERM...
(This evening through Friday)
Issued at 157 PM PDT Thu Jun 26 2025

Seasonal weather pattern continues this afternoon with sunny and
warm weather inland while a 1200 foot marine layer persists along
the coast with temps still hovering in the upper 50s and lower
60s. Still not seeing any real hot temps inland with lower 90s
confined to interior Monterey county. Northerly gradient from
SFO-ACV is now in excess of 4 mb with less stratus off the Sonoma
coast. Expect the shallow marine layer to slowly reorganize this
evening and spread into the coastal valleys overnight.

Building shortwave type ridge for Friday will continue to compress
the marine layer and lead to an inland warming trend Friday
afternoon. Expect to see lower 90s for the interior
North/South/East Bay for the first time this week. Microclimates
should be in full effect with temps ranging from 60 at Ocean Beach
to around 95 for the interior valleys. It`ll finally feel a
little more summer like inland Friday afternoon.

&&

.LONG TERM...
(Friday night through next Wednesday)
Issued at 157 PM PDT Thu Jun 26 2025

No big changes into Saturday with the ridge, so expect a shallow
marine layer and another day of inland temps in the 90s but the
coast and bays will remain mild to warm with temps running near
normal.

By Saturday night into Sunday the models are coming into agreement
that a weak low will spin up offshore, west of San Francisco. This
will likely induce a stronger southwesterly onshore wind pattern
on Sunday (kind of like a modified southerly surge). In addition
the upper low will likely deepen the marine layer. Therefore
expect a noted cooling trend for Sunday, especially places like
Santa Cruz (north side of Monterey Bay), Napa and Sonoma valleys
where southwesterly onshore push will be efficient for pushing up
those valleys.

Worth noting that on Sunday night the upper flow turns
southeasterly across NorCal. Gfs MUCAPE shows a few 100 J/kg but
it doesnt align with moisture. Best forecast keeps t-storms well
to our north and east but will monitor closely as it depends on
exact location of upper low. Usual scenario with these setups
would be convection over the Northern Sierra and the coastal
ranges from Mendocino northward.

The upper low looks to take up residence for much of next week per
the latest long range models. That would mean temps running near
to a few degrees below normal for late June/early July with a
fairly deep marine layer. Thus as we head towards 4th of July not
seeing any abnormally hot weather for the Bay Area with any precip
likely staying over the Sierra and southern deserts as monsoon
moisture slowly starts to eject out of AZ and Mexico.

&&

.AVIATION...
(18Z TAFS)
Issued at 1047 AM PDT Thu Jun 26 2025

MVFR currently at MRY, OAK and SFO with clearing anticipated by 19Z-
1930Z. Low ceilings (LIFR/IFR) at HAF that may linger through much
of the day. Winds increase this afternoon with gusty conditions at
most terminals, easing overnight and into Friday morning. However,
low clouds (IFR/MVFR with the greatest potential for LIFR at MRY and
SNS) are forecast to return to the Bay Area and Monterey Bay
terminals by late evening or early Friday morning. Any low ceilings
that do develop will clear out late Friday morning with increasing
onshore winds.

Vicinity of SFO...MVFR returning to VFR by late morning. Onshore
winds increase once again this afternoon with gusts currently
forecast to be 31 kt. Winds ease after sunset with a return to
IFR/MVFR ceilings. Any low clouds that do develop will
scatter out by 18Z Friday. Moderate confidence.

SFO Bridge Approach....The San Mateo Bridge Approach will likely
remain clear though the TAF period; however, low stratus clouds
between OAK, SFO, and northward through the Golden Gate Bridge are
forecast to return late this evening and into Friday morning.

Monterey Bay Terminals...MVFR at MRY returning to VFR by late
morning. Onshore winds increase this afternoon before easing late in
the evening. IFR/MVFR ceilings likely to return late this evening
and potentially lowering to LIFR early Friday morning. High
confidence.

&&

.MARINE...
(Today through Tuesday)
Issued at 1047 AM PDT Thu Jun 26 2025

Fresh to strong northwesterly breezes with near-gale force gusts
will continue through Friday. Gale force gusts can be expected
near the coastal jet regions of Point Reyes and Point Sur this
afternoon and evening. Moderate to rough seas will also continue
through Friday, with northwesterly winds easing over the weekend.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory from 11 PM this evening to 2 AM PDT
     Friday for CAZ006-506-508.

PZ...Small Craft Advisory until 9 PM PDT this evening for Mry Bay.

     Gale Warning until 9 PM PDT this evening for Pt Arena to Pt
     Reyes 0-10 nm.

     Small Craft Advisory until 3 AM PDT Friday for Pigeon Pt to Pt
     Pinos 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

     Small Craft Advisory until 3 PM PDT this afternoon for Pt Pinos
     to Pt Piedras Blancas 0-10 nm.

     Gale Warning until 3 AM PDT Friday for Pt Pinos to Pt Piedras
     Blancas 0-10 nm.

     Small Craft Advisory until 3 AM PDT Saturday for Pigeon Pt to Pt
     Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.

&&

$$

SHORT TERM...RW
LONG TERM....RW
AVIATION...RGass
MARINE...RGass

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