539
FXUS66 KMTR 180842
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
142 AM PDT Wed Sep 18 2024

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

.SYNOPSIS...
Issued at 1252 AM PDT Wed Sep 18 2024

Chance of scattered showers today, tapering off from north to
south gradually through Thursday morning. A warming trend is on
tap for the rest of the week with seasonal normal temps expected
by the weekend.

&&

.SHORT TERM...
(Today and Thursday)
Issued at 1252 AM PDT Wed Sep 18 2024

The next system is currently moving in, made noticeable by the
influx of higher cloud cover through the evening. As of about
midnight, the surface low was located just off the coast of
Oregon. The low will move southward through this morning, bringing
light rain chances to the Bay Area by mid-to-late morning. There
is a slight chance (~15%) of thunder during this time period,
mainly in the North Bay. As the low moves through, moisture
wrapping around the back side will affect areas south of the Bay
Area, including the Central Coast, by the middle of Thursday
morning. There is also a slight chance of thunder here during this
time. Though a small chance, there could be some terrain
enhancement over the Santa Lucia, resulting in isolated, brief
heavier rain than what will be seen elsewhere. Shower activity
ends gradually Thursday evening as the low moves inland.

&&

.LONG TERM...
(Friday through Tuesday)
Issued at 1252 AM PDT Wed Sep 18 2024

A warming trend will kick off Friday into the weekend as the upper
low exits and confidence grows in an a broad upper level ridge
situated off the west coast. Temperatures through the weekend are
expected to be near seasonal normals. Warming continues into early
next week where we will begin to see slightly above normal
temperatures.

&&

.AVIATION...
(06Z TAFS)
Issued at 1122 PM PDT Tue Sep 17 2024

Mid-level clouds as well as IFR and MVFR CIGs build through the
night last into the mid to late morning with light rain expected in
the mid to late morning. Pockets of drizzle and mist will affect the
coast as well as the Bays and STS in the late night ahead of the
rain chances and lingering slightly after. Winds stay light to
moderate through the morning. Widespread VFR returns for the TAF
sites into Wednesday afternoon, but status lingers on the immediate
coast. Expect moderate winds to build into the afternoon and linger
into the evening. Coastal cloud cover moves slightly early Tuesday
evening, affecting both bays with IFR and MVFR CIGS becoming
widespread later that night.

Vicinity of SFO...MVFR CIGs build into the late night and last into
the late morning with some shower activity in the mid morning.
Expect light to moderate winds overnight. CIGs erode as winds build
in the early afternoon. Winds will reduce slightly into Tuesday
evening and MVFR CIGs return in the late evening and early night.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...MVFR/IFR CIGs  with mist and drizzle ahead
of light scattered showers in the mid morning. CIGs scatter and
winds become more moderate into Wednesday afternoon. MVFR CIGs
return early Wednesday evening as winds reduce.

&&

.MARINE...
(Tonight through next Monday)
Issued at 1122 PM PDT Tue Sep 17 2024

Northwesterly breezes will be gentle to moderate, increasing to
become moderate to fresh over the outer waters by Thursday. Seas
will be moderate, building to become rough in the outer waters by
Thursday. There`s up to a 15% chance for thunderstorms tomorrow
which could produce lightning, locally heavy rainfall, locally
gusty winds, and small hail.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM Thursday to 3 AM PDT Friday for
     Pt Arena to Pt Reyes 10-60 NM.

&&

$$

SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...Murdock
MARINE...Sarment

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