855
FXUS66 KMTR 141131
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
431 AM PDT Tue May 14 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1217 PM PDT Mon May 13 2024

Relatively quiet pattern persists through the forecast period with
morning marine stratus and clear skies elsewhere. Inland
temperatures warm into the 70s and 80s each afternoon with a
persistent marine layer keeping coastal highs in the 60s.

&&

.SHORT TERM...
(Today and tonight)
Issued at 1217 AM PDT Tue May 14 2024

Low pressure aloft will migrate from SoCal into the Desert Southwest
as an expansive high pressure ridge encompasses much of the
northeast Pacific. Our area will remain on the eastern periphery of
the upper ridge with minimal changes to our sensible weather. A
relatively deep marine layer around 1.5-2 kft was evident via area
profilers early this morning, with low stratus clouds spilling
inland across most of the area. Expect the top of the marine layer
inversion to remain relatively steady this morning before
compressing slightly as high pressure gains a bit more influence.
However despite these modulations it`s mostly a rinse and repeat
forecast. Cloudy skies for the coast and marine influenced valleys
overnight with a gradual clearing towards the beaches during the
late morning to early afternoon hours. High temperatures will range
from the 60s along the coast and bays to the upper 70s and 80s for
the warmest inland locations. As mentioned in the previous
discussion some of the model temperature guidance seems a touch too
warm when compared to observations over the past few days, so
followed the previous forecast philosophy of trending slightly
cooler for readings in areas which are likely to see a stronger
marine influence. Otherwise not much else to add with overnight lows
remaining seasonal in the upper 40s and 50s.

&&

.LONG TERM...
(Wednesday through Monday)
Issued at 1217 AM PDT Tue May 14 2024

The upper level ridge will gain slight prominence through midweek,
however we will remain along its periphery with a minimal increase
in temperatures inland. Readings will range from the 60s along the
coast to the upper 80s for the warmest inland valleys. A few hot
spots may crack the 90 degree mark. Lows will be mostly in the 50s.
The daily ebb and flow of coastal clouds will continue, with
coverage spreading inland each night with a gradual retreat towards
the coast by afternoon. The upper level pattern may transition more
towards troughing by early next week but dry weather still looks to
be the most probable forecast outcome.

&&

.AVIATION...
(12Z TAFS)
Issued at 423 AM PDT Tue May 14 2024

Currently seeing a mix of LIFR-VFR at the terminals. The 2,000 feet
deep marine layer has allowed for stratus to penetrate further
inland and impact all terminals. Widespread VFR and breezy onshore
flow will prevail by this afternoon. A more compressed marine layer
will return tonight with LIFR-IFR conditions expected at the
favored locations of MRY, OAK, SFO, SNS, and STS.

Vicinity of SFO...Currently MVFR with breezy westerly flow. VFR to
prevail by late-morning. Winds will remain onshore and breezy
through the TAF period with gusts up to 25 knots to be expected this
afternoon. The terminal will likely see a ceiling overnight
somewhere in the realm of low-end MVFR-high-end IFR.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently IFR with southerly flow at MRY
and VFR with westerly flow at SNS as the stratus has temporarily
eroded. VFR to prevail by this afternoon. Winds will remain
onshore through the TAF period. MRY will quickly deteriorate to
IFR again tonight with SNS following suit a few hours later.

&&

.MARINE...
(Today through Sunday)
Issued at 423 AM PDT Tue May 14 2024

Surface high pressure over the Eastern Pacific Ocean will dominate
and dictate conditions over the coastal waters this week. Said
surface high pressure will build and move east today, allowing for
strong northerly breezes over the northernmost outer waters where
the pressure gradient is tightest with gentle to moderate
northwesterly breezes elsewhere. A brief retrograde to the west
will  allow for light to gentle breezes to prevail Wednesday and
Thursday.  Significant wave heights of 10-14 feet will begin an
abating trend  tonight.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Pt Arena to
     Pt Reyes 10-60 NM.

&&

$$

SHORT TERM...SPM
LONG TERM....SPM
AVIATION...Sarment
MARINE...Sarment

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