FXUS66 KMTR 101954
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1254 PM PDT Sun May 10 2026
...New SHORT TERM, LONG TERM...
.KEY MESSAGES...
Updated at 1252 PM PDT Sun May 10 2026
- Warming and drying trend will continue through Monday
- Moderate risk for heat-related illnesses for sensitive
populations across the interior on Monday
- Gradual cooling trend and unsettled weather midweek through
late week
&&
.SHORT TERM...
Issued at 1252 PM PDT Sun May 10 2026
(This evening through Monday)
Temperatures this afternoon are struggling to reach their forecasted
highs. This is as a deeper marine layer around 1500 ft in the North
Bay and 2000 ft in the Bay Area and Central Coast developed
overnight. Again, where cloud cover lingers or is slow to dissipate
across inland areas is where we are most likely to see cooler
temperatures than previously forecasted. That said, inland clearing
will still allow for temperatures to warm this afternoon as high
pressure to the south of the region continues to strengthen.
Overnight, temperatures will cool into the upper 40s to mid 50s
across most valley locations. Meanwhile, the higher ridges and peaks
will likely bottom out in the upper 50s to 60s. If persistence
holds, low clouds will fill back inland overnight, yet not expecting
as much of an inland penetration as the marine layer is still on
track to compress.
Monday is still on track to be the warmest day of the week, yet we
are seeing less widespread Moderate HeatRisk across the interior.
Mondays afternoon maximum temperatures are expected to be in the mid
80s to lower 90s across the interior with cooler conditions near the
coast as a shallow marine layer and onshore flow will persist.
However, these temperatures could be off by a few to several degrees
where cloud cover develops and lingers. Tricky forecast as high
pressure aloft supports warming afternoon temperatures, yet the
marine influences have been winning out.
&&
.LONG TERM...
Issued at 1252 PM PDT Sun May 10 2026
(Monday night through next Saturday)
The pattern begins to shift Monday night into Tuesday as a trough of
low pressure approaches the Pacific Northwest and northern
California. Thus, temperatures will cool by several degrees on
Tuesday, yet are likely to remain above seasonal averages. A cut-off
low pressure system is forecast to develop and move inland Tuesday
night and into Wednesday bringing even cooler and unsettled weather
to the region. We are still expecting drizzle and/or light rain
Tuesday night through Thursday morning as a result of the mid/upper
level cut-off low moving inland across northern California or the
Bay Area. Rainfall amounts generally will remain less than a few
hundredths of an inch or so.
More of a zonal flow returns by late week and will persist through
the upcoming weekend. This will result in a warming and drying trend
through this timeframe.
&&
.AVIATION...
(18Z TAFS)
Issued at 1059 AM PDT Sun May 10 2026
Stratus is receding across the region with most sites to see CIGs
clearing between 18/19Z. The question is if we will see clearing at
HAF and MRY where continuous stratus feeds may allow overcast
conditions to persist through the majority of the TAF period. Breezy
afternoon/evening winds are likely again with gusts peaking between
20-25 knots. Locally stronger gusts are possible at SFO but they
should stay below 30 knots on the higher end. Winds ease overnight.
Stratus has returned early the last few days but models have started
shifting tonight's return to be later in the TAF period with the
stratus footprint potentially not as widespread tonight compared to
previous nights. This is reflected by the marine layer dropping from
around 2000 ft to around 1000 ft. MVFR-IFR CIGs are expected tonight
but, especially on the coast, we may see further lowering and
decreases in visibility (LIFR) as the marine layer compresses.
Vicinity of SFO...IFR with stratus to clear/VFR by 19/20Z. Winds
strengthen during the afternoon/evening with gusts to around 28
knots. Model guidance keeps gusts today well below 30 knots but
confidence is low to moderate. The SFO-WMC gradient looks to peak
around +6-7 mb today which would support decently gusty winds this
afternoon and evening. The 28 knot gusts listed in the TAF are on
the higher end but SFO has seen gusts to 30-31 knots over the last
few days with a much weaker SFO-WMC gradient. There is enough
reasonable confidence given persistence and the strengthening SFO-
WMC gradient to suggest moderate to strong gusts will redevelop
again this afternoon. The stratus forecast is a little lower
confidence given the compressing marine layer. The most likely
scenario is stratus returning after 06Z and lingering through 17/18Z
tomorrow. LAMP guidance suggests some potential for stratus to
return as early as 03Z.
SFO Bridge Approach....Similar to SFO.
Monterey Bay Terminals...MVFR-IFR with stratus coverage receding
across the Salinas Valley. Similar to yesterday, stratus continues
to feed in along the Monterey Bay shoreline (including MRY). MRY is
expected to maintain overcast conditions through at least 22Z before
potentially remaining clear through 02Z. CIGs return to SNS by late
tonight but there is some potential for an early return (02-03Z)
similar to MRY. Gusty onshore winds are likely again during the
afternoon/evening before winds diminish overnight.&&
.MARINE...
(Today through Friday)
Issued at 855 AM PDT Sun May 10 2026
Moderate seas and a fresh to strong northwest breeze with
occasional near gale force gusts will continue through tonight.
Locally gusty conditions are likely across the San Pablo and San
Francisco Bays where terrain promotes wind funneling. Winds
gradually ease starting late tonight across the inner waters then
across the outer waters tomorrow becoming a moderate northwest
breeze. Winds increase and seas build mid to late week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Mry Bay.
Small Craft Advisory until 3 AM PDT Monday for Pt Arena to Pt
Reyes 0-10 nm.
Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt
to Pt Pinos 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm-
Pt Reyes to Pigeon Pt 0-10 nm.
Small Craft Advisory until 3 PM PDT Monday for Pt Arena to Pt
Reyes 10-60 NM.
Small Craft Advisory until 9 AM PDT Monday for Pigeon Pt to Pt
Pinos 10-60 NM.
&&
$$
SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Kennedy
MARINE...Kennedy
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Prepared by Boulder-Creek.com Weather at: Sun May 10 14:30:02 PDT 2026
From the National Weather Service
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