Hacienda, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

083
FXUS66 KMTR 150941
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
241 AM PDT Thu May 15 2025

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

.SYNOPSIS...
Issued at 127 AM PDT Thu May 15 2025

Subtle warming trend under way with fair weather through the end
of the week. High wind potential by Saturday through Monday
morning across much of the region. Warm next week.

&&

.SHORT TERM...
(Today and Friday)
Issued at 127 AM PDT Thu May 15 2025

Evidence of fair weather and high pressure aloft in the marine
layer this morning, which has become well-formed and compressed to
about 1,000 ft. Looking at the 24 hour change in temperatures this
morning; overall, temps are about 1-3 degrees warmer than 24 hours
ago. Expecting the same in afternoon high temperatures as well,
which will be slightly above seasonal averages. Not expecting any
impacts over the next couple of days as this pattern persists
through Friday. Things start to change late Friday as we get into
the weekend and a potent upper low digs into the western US.

&&

.LONG TERM...
(Saturday through Wednesday)
Issued at 127 AM PDT Thu May 15 2025

Continued high confidence in high winds resulting in minor to
moderate impacts this weekend. By early Saturday morning, a
robust 130 kt jet begins to impinge upon the West Coast as a deep
upper low digs into the Great Basin. There is a non- zero chance
of some isolated drizzle Saturday morning as the marine layer is
lifted and eventually mixed out by the approaching trough. Lower
level flow begins to increase by midday Saturday with 700 mb flow
approaching 50 kts over the waters. The flow regime largely
remains northwesterly and parallel to the coast. This may act to
limit some of the impact to land, thus limiting the potential for
widespread advisory-level winds. However, locations along the
coast and notable NW-SE valleys (i.e. Salinas Valley and the San
Bruno Gap) are likely to see gusts into the 40-50 mph range.
Elsewhere over land we are expecting gusts in the 30-40 mph range.
Holding off on an advisory for now, but will need to keep watch on
the possibility for a targeted advisory along coastal areas and
favored valleys. As the system exits, the flow upstream of the
trough axis veers more northerly and surface high pressure builds
as large scale subsidence sets in. The result will be a brief
period of offshore winds in the North Bay late Sunday night and
early Monday morning. No major concerns regarding fire weather for
now, but will keep an eye for increased messaging, especially
inland Napa Co.

Beyond the weekend system, strong high pressure is expected to
build through the middle of next week promoting above average
temperatures.

&&

.AVIATION...
(06Z TAFS)
Issued at 1103 PM PDT Wed May 14 2025

Patchy stratus is expected tonight primarily along the coastline and
eastern portion of the SF Bay. HAF, MRY, SNS, and OAK are expected
to see MVFR to IFR conditions overnight with highest confidence in
MVFR to IFR CIGs at MRY. Current thinking is that the NBM is too
widespread in stratus coverage as it shows stratus pushing into much
of the Bay Area and Central Coast. The combination of drier air
aloft and a more compressed marine layer (~1000 ft) pushed thinking
more towards the HRRR and HREF models which supported patchy stratus
development along the coast and limited the inland extent of
stratus. Current thinking is that conditions will be too dry to
support fog at STS or APC but if any does develop it will likely be
in the 12Z-17Z timeframe. Breezy onshore winds return tomorrow
during the afternoon/evening before winds diminish overnight.

Vicinity of SFO...VFR through the TAF period. Continued to lean
towards HRRR and HREF guidance which support patchy stratus across
the Bay Area but do not show it filling in across the SF Bay region.
Confidence is moderate that conditions will stay VFR through the TAF
period but if MVFR CIGs do develop, LAMP guidance indicates 12Z-16Z
as the most likely timeframe. Current thinking is that conditions
will be too dry to support stratus developing across the SF Bay but
ensembles do show some potential for this to occur. Breezy onshore
winds continue to diminish this evening before increasing again
tomorrow during the day.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...MVFR to IFR overnight becoming VFR during
the day. Satellite shows MVFR CIGs have reached MRY and are starting
to fill in around SNS. Stratus is expected to persist at both sites
through mid to late tomorrow morning with low to moderate confidence
that IFR CIGs will develop at MRY. MVFR CIGs will fill in at SNS
over the next few hours with patchy MVFR CIGs expected through 10Z.
Light onshore flow continues overnight before moderate northwest
winds return during the day tomorrow.&&

.MARINE...
(Tonight through next Tuesday)
Issued at 1103 PM PDT Wed May 14 2025

Strong, gale force northwesterly winds continue across the outer
coastal waters while fresh to strong northwesterly winds continue
across the inner coastal waters. Moderate seas bringing steep,
fresh  swell will continue through Saturday with significant wave
heights  between 10 to 12 feet expected across the outer waters.
Sunday into  next week, gale force to near gale force winds will
become more  widespread over the coastal waters and seas will
become rough.  Hazardous conditions will continue through the end
of the forecast  period.

&&

.MARINE...
(Tonight through next Tuesday)
Issued at 1103 PM PDT Wed May 14 2025

Strong, gale force northwesterly winds continue across the outer
coastal waters while fresh to strong northwesterly winds continue
across the inner coastal waters. Moderate seas bringing steep,
fresh  swell will continue through Saturday with significant wave
heights  between 10 to 12 feet expected across the outer waters.
Sunday into  next week, gale force to near gale force winds will
become more  widespread over the coastal waters and seas will
become rough.  Hazardous conditions will continue through the end
of the forecast  period.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM Friday to 3 AM PDT Saturday for
     Mry Bay-SF Bay N of Bay Bridge.

     Small Craft Advisory from 9 AM this morning to 9 PM PDT this
     evening for Mry Bay.

     Gale Warning until 3 AM PDT Saturday for Pigeon Pt to Pt Pinos
     10-60 NM-Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes
     10-60 NM-Pt Reyes to Pigeon Pt 0-10 nm.

     Small Craft Advisory until 9 AM PDT Friday for Pigeon Pt to Pt
     Pinos 0-10 nm.

     Gale Warning from 9 AM Friday to 3 AM PDT Saturday for Pigeon Pt
     to Pt Pinos 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory until 3 AM PDT early this morning for Pt
     Pinos to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory from 3 PM this afternoon to 9 AM PDT Friday
     for Pt Pinos to Pt Piedras Blancas 0-10 nm.

&&

$$

SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...Kennedy
MARINE...Kennedy

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