237
FXUS66 KMTR 061749
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1049 AM PDT Sun Jul 6 2025

...New AVIATION, MARINE...

.KEY MESSAGES...
Updated at 257 AM PDT Sun Jul 6 2025

 - Temperatures remain below seasonal averages through early next
   week.

 - The marine layer continues to deepen and expand farther inland
   through early next week, bringing widespread stratus overnight.

 - Gradual pattern change midweek remains on track with a warming
   trend to start Wednesday.

&&

.SHORT TERM...
Issued at 257 AM PDT Sun Jul 6 2025
(Today and tonight)

An upper level closed low off the coast of Northern California will
linger off the coast of the Bay Area Sunday into the early work
week. This will result in seasonal to below normal temperatures with
highs in the upper 70s to 80s across the interior and upper 50s to
60s along the coastline. The warmest locations within the interior
Central Coast and far interior East Bay Hills will reach the low 90s
today. For context, today`s forecast high temperatures are running
approximately 5 to 10 degrees below normal for this time of year
with below normal temperatures expected to continue for the first
half of the upcoming week. The marine layer has deepened to around
1000ft to 1200 ft this morning with further deepening to 1500-2000ft
expected tonight. Satellite shows stratus extending along much of
the coastline and filtering into the San Francisco Bay shoreline and
portions of the interior valleys. Conditions will start to clear by
mid to late morning but widespread stratus is expected to return
late tonight, continuing overnight into Monday. Locally breezy winds
with gusts to around 25 mph are expected across the Altamont Pass
region and Salinas Valley this afternoon and evening. Otherwise,
today remains fairly pleasant and will be a good day to get
outside.

&&

.LONG TERM...
Issued at 257 AM PDT Sun Jul 6 2025
(Monday through Saturday)

For the first portion of the Long Term (Monday-Tuesday), not much
changes compared to this weekend. The upper level closed low will
linger off the coast of the Bay Area through Tuesday, keeping
temperatures below normal and maintaining a fairly deep marine
layer. Highs across the interior will generally be in the 70s to 80s
with the warmest interior locations reaching the low 90s. Coastal
areas will continue to see cooler areas in the upper 50s to 60s. In
terms of stratus, "No Sky July" is well underway for coastal areas
with coastal locations to see stratus returning each night and
dissipating by mid to late morning. Stratus is expected to push into
the San Francisco Bay Shoreline, portions of the Santa Clara Valley,
and the North Bay Valleys Monday and Tuesday nights as the marine
layer deepens to around 1500-2000ft. Coastal drizzle is likely
overnight Monday and Tuesday with the persistent upper level closed
low and deeper marine layer.

For the second part of the Long Term (Wednesday-Saturday), the upper
level closed low begins to weaken Wednesday and progresses into far
northern CA and Oregon. As this occurs, upper level high pressure
over the Four Corners region expands and shifts into southern
California, bringing zonal flow to slight ridging over the Bay Area.
this will kick off a warming trend with highs in the 80s to 90s
across the interior. The warmest locations (portions of the East Bay
Hills, Interior North Bay Mountains, and Interior Central coast)
will reach the upper 90s to low 100s. The warmest days this week
look to be Thursday and Friday where moderate HeatRisk is set to
impact the Bay Area. Moderate HeatRisk impacts anyone who is
sensitive to heat and does not have access to adequate
cooling/hydration. Temperatures remain warm on Saturday but will be
a few degrees cooler with highs generally in the 80s to low 90s
across the interior. It is worth noting that models continue to have
trouble with if more zonal flow vs shortwave ridging will develop
which may result in changes to the forecast temperatures for next
week.

&&

.AVIATION...
(18Z TAFS)
Issued at 1048 AM PDT Sun Jul 6 2025

IFR to MVFR stratus persist at coastal sites with sky conditions
either scattering out or clearing completely across the interior.
Moderate confidence for IFR to MVFR conditions to linger at the
coast throughout the remainder of the day, yet cannot rule out a few
hours of low clouds scattering out this afternoon. Onshore winds
increase this afternoon before diminishing after sunset. Moderate to
high confidence for an early return late tonight of stratus filling
into the coastal valleys and lowering early Monday morning. Low
clouds that do develop by Monday morning will likely scatter out
and/or clear by Monday afternoon, with the exception of coastal
locations.

Vicinity of SFO...VFR. Onshore winds increase this afternoon before
gradually easing after sunset. High confidence for MVFR ceilings to
return late tonight and potentially lowering to IFR at times early
Monday morning. Stratus is forecast to scatter out between 16Z-18Z
Monday morning.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...IFR at MRY, VFR at SNS. Moderate
confidence for IFR/MVFR ceilings to linger throughout much of the
day at MRY while sky conditions have scattered out at SNS. Onshore
winds will increase this afternoon before easing after sunset.
High confidence for IFR/MVFR ceilings to return this evening and
lower to LIFR at times early Monday morning.

&&

.MARINE...
(Today through Friday)
Issued at 1048 AM PDT Sun Jul 6 2025

Fresh northwesterly breezes will continue today for the outer
waters and coastal jet regions of Point Reyes and Point Sur. Winds
gradually begin to slack Monday with moderate to fresh breezes
forecast through Wednesday with a surface low positioned over the
outer waters. Northwesterly winds increase and significant wave
heights build beginning late in the week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT Monday for Pt Arena to Pt
     Reyes 10-60 NM.

&&

$$

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

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