Stanford, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

971
FXUS66 KMTR 192029
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
129 PM PDT Sat Apr 19 2025

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

.SYNOPSIS...
Issued at 127 PM PDT Sat Apr 19 2025

Slight warming trend expected Monday and Tuesday before cooler,
cloudier conditions return Wednesday into the weekend. Continuing
to monitor a slight chance for light rain Friday into the weekend.

&&

.SHORT TERM...
(This evening through Sunday)
Issued at 127 PM PDT Sat Apr 19 2025

Stratus is dissipating across the interior but persists along the
coastline. The exception to this is interior Sonoma County where a
circulation just offshore continues to feed stratus into the Sonoma
Valley. Nudged high temperatures along the coast down by 2-3 degrees
to account for continued stratus coverage along the coast with highs
forecast to reach the upper 50s to low 60s. Across the interior,
clearing skies will allow for increased radiational warming with
highs to reach the upper 60s to mid 70s. Some uncertainty remains
about high temperatures across the Sonoma Valley, if stratus
coverage is able to dissipate within the next few hours then high
temperatures are likely to reach the low 70s. If stratus coverage
persists into the mid to late afternoon, high temperatures will
struggle to reach the upper 60s. We`ll keep an eye on satellite and
evaluate if any changes need to be made for today`s forecast across
the North Bay. Light, onshore winds will persist through the
remainder of the weekend with locally breezier conditions across the
elevated terrain. A weak shortwave trough will move through the
region this evening into Sunday. This disturbance will allow the
marine layer to deepen to around 2000ft and bring widespread
overcast conditions to the Bay Area and Central Coast. High
temperatures on Sunday are forecast to be in the low to mid 70s
across the interior and upper 50s to mid 60s along the coastline.
The main question for tomorrow`s forecast is how long stratus
coverage will persist and what impact that will have on the high
temperatures. We may expect to see a similar setup to today, where
areas that have prolonged stratus coverage may struggle to reach
their forecast highs vs areas that clear faster will reach their
forecast highs more easily.

&&

.LONG TERM...
(Sunday night through next Friday)
Issued at 127 PM PDT Sat Apr 19 2025

By Sunday evening, the weak upper level disturbance will have exited
the region with high pressure and zonal upper level flow replacing
it. High resolution guidance shows the marine layer compressing to
around 500 ft starting Sunday night and remaining compressed through
Tuesday. The combination of a compressed marine layer, zonal flow,
and high pressure will result in rising temperatures Monday and
Tuesday. Temperatures across the interior will be about 5 to 10
degrees above normal in the mid to upper 70s with a few areas
possibly reaching the low 80s. Along the coast temperatures will be
cooler, more seasonal, with highs in the low to mid 60s expected.
Minor HeatRisk persists Monday and Tuesday for portions of the Bay
Area and Central Coast but this will primarily only impact
individuals who are incredibly sensitive to heat.

The pattern shifts Wednesday with interior temperatures going from
above normal to below normal as zonal upper level flow gives way to
upper level troughing. A weaker upper level trough will arrive
Wednesday, giving way to weak ridging on Thursday, before a deeper
upper level trough arrives Friday. This second trough (Friday into
the weekend) will be associated with a surface low pressure system
and a cold front moving through the region. Temperatures will cool
to the mid to upper 60s across the interior and to the upper 50s to
low 60s along the coast starting Wednesday. Cooler temperatures will
persist through the end of the forecast period with CPC guidance
highlighting below normal temperatures continuing through the end of
April. We are still monitoring potential for light rain towards the
end of the forecast period (Friday into the weekend) with ensemble
guidance indicating some potential for light rain. However, there is
still a fair amount of uncertainty regarding how deep upper level
troughing will be and how far south rain will spread. For example,
the previous forecast update showed more widespread light rain
across the Bay Area and Central Coast while this afternoon`s limited
it to the North Bay. It is likely we will see some light rain from
this system but it is still too far out for exact locations and
forecast amounts. Initial NBM guidance suggests some potential for
breezier conditions next weekend as this system moves through the
region. Guidance is likely to continue fluctuating in the short term
with forecast confidence increasing as we get closer to the end of
next week.

&&

.AVIATION...
(18Z TAFS)
Issued at 1133 AM PDT Sat Apr 19 2025

Stratus clouds /MVFR-IFR/ are steadily eroding inland under diurnal
surface warming and mixing, while stratus continues closest to the
coastline. The marine layer depth was 1600 feet on the morning
12z Oakland upper sounding, while recent profiler data at Fort Ord
and Point Sur show the marine layer depth along the north Central
Coast has deepened to 2500 feet. Weak cyclonic surface winds
prevail over the coastal waters with pressure gradients SFO-SAC
1.2 mb, STS-UKI 1.9 mb and SNS-SJC 1.7 mb supportive of onshore
winds. The highest probability of VFR will be during the afternoon
coinciding with maximum diurnal warming and mixing. For tonight
and Sunday an approaching cool front and onshore winds will usher
stratus /MVFR-IFR/ inland early and likely farther inland Sunday
morning (compared to this morning) based on recent HRRR and HREF
output.

Vicinity of SFO...VFR is forecast for the remainder of the morning
and through the afternoon. Stratus continues to mix out per recent
satellite imagery. The OAK-SFO pressure gradient is currently 0.3
mb supporting temporary light northeast wind until 20z this
afternoon. A west wind will resume with gusts near 20 knots during
the afternoon and early evening. Stratus clouds will likely
remain on the doorstep just west of the peninsula, with a return
of stratus /MVFR/ 03z this evening. MVFR in stratus tonight and
Sunday morning with mix out time forecast 1930z.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Southerly to westerly winds from the inner
coastal waters to the Monterey Bay continue to advect stratus
/MVFR-IFR/ inland while erosion of stratus continues along the
inland edges of the stratus. It`ll take up to another couple hours
for the stratus to erode to VFR at the nearby airport terminals.
Best probability for VFR is during the afternoon, then stratus
/MVFR-IFR/ returns early evening and remaining for tonight and
Sunday morning. Winds mainly onshore 5 to 12 knots.

&&

.MARINE...
(Tonight through next Thursday)
Issued at 127 PM PDT Sat Apr 19 2025

Breezy to gusty winds increase through the day specifically over
the northern outer waters, as a weak cold front approaches from
the north. The increasing winds will result in a building
northerly fresh swell. Gusty winds spread across the waters into
the next work week and look to remain through the week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM Sunday to 3 AM PDT Monday for Pt
     Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory until 3 PM PDT Monday for Pt Arena to Pt
     Reyes 10-60 NM.

     Small Craft Advisory from 9 AM Sunday to 3 PM PDT Monday for
     Pigeon Pt to Pt Pinos 10-60 NM.

&&

$$

SHORT TERM...Kennedy
LONG TERM....Kennedy
AVIATION...Canepa
MARINE...Canepa

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