810
FXUS66 KMTR 261748
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1048 AM PDT Thu Sep 26 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 103 AM PDT Thu Sep 26 2024

Expect a gradual warming trend through Friday as high pressure
builds over the Desert Southwest. Temperatures return to near
seasonal averages for the upcoming weekend with a warming trend
into Tuesday.

&&

.SHORT TERM...
(Today and tonight)
Issued at 103 AM PDT Thu Sep 26 2024

Widespread cloud cover has returned, in some cases never left near
the coast, with ceilings between 700-1,500 feet. Temperatures
however are likely to cool into the low-to-upper 50`s across the
region this morning. Again, cannot rule out mist and/or light
drizzle this morning in typically favored spots in response to the
deepening marine layer at just above 2,000 feet in depth per the
Fort Ord Profiler.

Today, we kick off the warming trend with temperatures near or
slightly above seasonal averages. Low clouds will clear by late
morning or early afternoon. Afternoon maximum temperatures are
forecast to be in the mid 80`s to low 90`s in the warmest interior
locations, 70`s to low 80`s just inland, and upper 50`s to mid 70`s
near the coast.

Tonight, expecting subtle warming for most urban areas by a few
degrees but much warmer in the higher elevations as the air mass
warms in response to high pressure building over the Desert
Southwest. Thus, expecting temperatures to range from the 60`s to
mid 70`s in the higher terrain. Low clouds will be less widespread
overnight, yet pose a bit of a challenge forecast wise as the marine
layer compresses under the aforementioned high pressure.

&&

.LONG TERM...
(Friday through Wednesday)
Issued at 103 AM PDT Thu Sep 26 2024

Friday will be the warmest day as we head into the weekend with a
~590mb upper level high building over the Desert Southwest. As such,
expecting more widespread 90`s across the interior, 80`s to low 90`s
around the Bay Shoreline, and upper 60`s to mid 80`s near the coast.
The ridge will be flatten on Saturday and Sunday as an upper level
trough moves into the Pacific Northwest. However, this will only
bring temperatures back down to seasonal norms. Another warming
trend will resume on Monday with high pressure becoming the dominate
feature aloft with continued warming into Tuesday. CPC outlooks
continue to show a lean towards temperatures above, and
precipitation below, seasonal averages through the first week of
October.

&&

.AVIATION...
(18Z TAFS)
Issued at 1047 AM PDT Thu Sep 26 2024

Currently a mixed bag of LIFR-VFR as stratus is rapidly dissipating.
The marine layer is currently observed at 1,600 feet and is expected
to further compress through the TAF period as high pressure over the
Great Basin retrogrades to the west overnight. Winds will become
light and offshore overnight as the onshore gradient weakens,
resulting in further drying. All of this has lead to moderate to
high confidence in all terminals with the exception of the Monterey
Bay terminals of MRY and SNS remaining VFR through the TAF period as
a compressed/shallow marine layer remains confined to the coast.

Vicinity of SFO...Currently VFR with northerly flow. High confidence
in the terminal remaining VFR through the TAF period. Winds will
likely continue to veer towards an offshore heading before the sea
breeze kicks in this afternoon. Winds will become light overnight
and follow a backing pattern before the sea breeze kicks in tomorrow
afternoon.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently VFR with northerly flow at MRY
and VFR with drainage flow at SNS. Winds will prevail out of the
northwest today with MRY transitioning to become offshore overnight
and SNS resuming drainage flow. High confidence in both terminals
developing low-end IFR ceilings overnight. There is potential on
ceilings and/or visibilities further deteriorating to LIFR, it will
just depend on if the marine layer remains in tact or if
it completely erodes.

&&

.MARINE...
(Today through Tuesday)
Issued at 1047 AM PDT Thu Sep 26 2024

A parade of low pressure systems to the north will support
moderate to fresh northwesterly breezes. Over the outer waters,
seas will be rough and gusts will be strong.

&&

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

     Small Craft Advisory from 3 PM this afternoon to 9 AM PDT Friday
     for Pigeon Pt to Pt Pinos 10-60 NM.

&&

$$

SHORT TERM...RGass
LONG TERM....RGass
AVIATION...Sarment
MARINE...Sarment

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