Pacheco, California Weather Forecast Discussion

428
FXUS66 KMTR 201150
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
450 AM PDT Sat Sep 20 2025
...New AVIATION...
.KEY MESSAGES...
Updated at 257 AM PDT Sat Sep 20 2025
- Weekend warm up starts today
- Weak offshore flow on Monday
- Rainfall chances increase again early next week
&&
.SHORT TERM...
Issued at 257 AM PDT Sat Sep 20 2025
(Today and tonight)
Water vapor satellite imagery this morning shows an upper low
sitting off the coast of CA, with fairly dry air overhead.
Additional pictures from space show pockets of stratus trying to fill
into some valleys. Outside of that, fairly quiet weather is forecast
for today with a warming trend kicking off. Highs today upper 70s to
mid 80s for most interior locations with the exception being
interior Monterey and San Benito counties where the low 90s are
possible. For those near the coast, highs will range from the 60s to
mid 70s.
&&
.LONG TERM...
Issued at 257 AM PDT Sat Sep 20 2025
(Sunday through Friday)
Some minor changes in the long term. The upper level pattern will
gradually shift late Sunday into Monday with the upper level low
deepening off the southern coast of CA and upper level ridge
trying to nose into NorCal. This will lead to continued warming
through Monday, before ridging gives way to the closed low and
moving into southern CA. As of right now, the forecast looks to be
dry into early next week, with perhaps some light offshore winds
Monday into Tuesday. The next chance for showers or isolated
thunderstorms looks to be Tuesday into Wednesday, as the low moves
onshore and pulls moisture into the region.
&&
.AVIATION...
(12Z TAFS)
Issued at 431 AM PDT Sat Sep 20 2025
Spottier low clouds have been mixing in and out across the region
as warmer air aloft has been clearing some of the lower cloud
cover. This back and forth of low cloud cover last through the
morning. Stratus looks to clear by mid to late morning as winds
build. Winds reduce again into the early to mid evening with
IFR/MVFR CIGs building along the coast and the bays.
Vicinity of SFO...MVFR CIGs and light winds last into the late
morning. Expect VFR into the afternoon as moderate winds become
breezy. Winds reduce into the late evening as MVFR CIGS fill over
SFO and last into into Sunday afternoon.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...CIGs rebuild at MRY in the mid morning
but clear again into the late morning as winds increase into the
afternoon. VFR lasts into the early evening before winds reduce
and MVFR/IFR CIGs rebuild.
&&
.MARINE...
(Today through Thursday)
Issued at 257 AM PDT Sat Sep 20 2025
Winds stay mostly light across the waters aside from locally
breezy conditions near the favored coastal jets. Winds begin to
increase in the northern waters into Sunday afternoon. These
winds spread across the coastal waters into the work week with
locally near gale force gusts across the northern outer waters.
Winds decrease to moderate to fresh across the coastal waters
Tuesday through late 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-Pt Arena to Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...KR
LONG TERM....KR
AVIATION...Murdock
MARINE...Murdock
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NWS MTR Office Area Forecast Discussion