Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA

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931
FXUS66 KMTR 130949
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
249 AM PDT Thu Jun 13 2024

...New SYNOPSIS, SHORT TERM, MARINE...

.SYNOPSIS...
Issued at 247 AM PDT Thu Jun 13 2024

Quiet through the rest of the week with slight warm up on Friday
across the interior. Near normal temperatures by the weekend.
Increasing confidence for high wind potential and increased fire
danger Sunday into early next week.

&&

.SHORT TERM...
(Today through Friday)
Issued at 247 AM PDT Thu Jun 13 2024

Temperatures this afternoon will be similar to those yesterday as
zonal flow conditions north of the region while an upper level low
remains parked off of southern California. Temperatures this
afternoon will range from the upper 50`s to 60`s near the coast and
bayshore, 70`s to near 80 degrees just inland and into the East Bay,
Santa Clara Valley, and southern Salinas Valley. The regions
farthest interior will reach into the upper 80`s to low 90`s.

Tonight, expecting less widespread stratus to penetrate inland as
the marine layer begins to compress. Overnight low temperatures are
forecast to be in the upper 40`s across the North Bay and San
Francisco Peninsula with low/mid 50`s elsewhere.

Friday will be slightly warmer in response to increased sunshine,
northerly winds, and weak ridging aloft. Coastal/bayshore areas will
remain cool but the interior will see more upper 80`s to low 90`s.

&&

.LONG TERM...
(Friday night through Wednesday)
Issued at 247 AM PDT Thu Jun 13 2024

Heading into the weekend will be relatively quiet as temps cool a
bit again down to around seasonal normals. The real story will be
later in the weekend and into early next week. A deep upper low
currently up in the Gulf of Alaska becomes dislodged and moves
into the Pacific Northwest, kicking off another deep disturbance
sliding into the West Coast/Great Basin. Well advertised by
ensemble cluster analysis, there is high confidence in this
pattern change taking place Sunday into Tuesday. Placement of the
upper level trough axis is key when determining where the
strongest winds will be and their direction. There is higher
confidence that the strongest winds will remain over the waters
and near coastal areas, including more inland coastal gaps such as
the Petaluma Gap, San Bruno Gap, and other NW-SE oriented valleys.
While we aren`t expecting any widespread offshore winds as of this
forecast, the positioning of the trough will ultimately be the
deciding factor, so stay tuned to future updates as confidence
gradually increases. With grasses and fine fuels drying out
rapidly, it looks like the Sunday-Monday timeframe is one to watch
when it comes to elevated fire danger, particularly in the North
Bay where fine fuels are drier than elsewhere around the Bay Area
and Central Coast. For now, moisture recovery looks decent going
into the weekend as winds should remain onshore, but we are
keeping a close eye on the positioning of the trough and will
update messaging accordingly.

&&

.AVIATION...
(06Z TAFS)
Issued at 1059 PM PDT Wed Jun 12 2024

VFR through the TAF period for SF Bay terminals, though North Bay
and Monterey Bay terminals are expected to develop or maintain
IFR/LIFR CIGs through the majority of the overnight period tonight.
For North Bay terminals, IFR conditions are expected to improve as
CIGs lift beyond sunrise, with clearing to VFR shortly after.
Meanwhile, Monterey Bay terminals are not expected to clear to VFR
during the day on Thursday. Winds light overnight tonight, but
increase to become breezy into the afternoon of Thursday.

Vicinity of SFO...VFR through the TAF period, with moderate
confidence. Stratus may hover near the terminal, but not expecting
CIGs to develop. Winds generally light overnight but increase out of
the SW in the morning to become breezy, eventually turning to flow
out of the NW in the late afternoon. Winds then decrease into the
late night of Thursday.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently IFR as stratus continues to feed
inland off of the coast. CIGs are expected to lower throughout the
night, eventually leading to the development of LIFR conditions.
Heavy mist is likely to develop as CIGs lower as well, lowering
visibilities significantly in the overnight tonight. Towards
sunrise, CIGs will begin to lift, eventually becoming MFR towards
the late morning. Not expecting clearing for KMRY or KSNS terminals
Thursday. Winds W/SW and breezy. A return to IFR conditions expected
in the late night of Thursday.

&&

.MARINE...
(Today through Tuesday)
Issued at 247 AM PDT Thu Jun 13 2024

Fresh northwesterly winds continue over the northern waters
through the end of the week. Towards the weekend, northwesterly
winds strengthen to become strong and gusting to gale-force over
much of the waters. Significant wave heights up to around 12 to
15 feet in the outer waters continue into the weekend.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 AM PDT early this morning for Pt
     Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory from 3 PM this afternoon to 9 AM PDT Friday
     for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-
     10 nm.

     Gale Warning until 3 AM PDT early this morning for Pt Arena to
     Pt Reyes 10-60 NM.

     Small Craft Advisory until 9 AM PDT Friday for Pt Arena to Pt
     Reyes 10-60 NM.

&&

$$

SHORT TERM...RGass
LONG TERM....Behringer
AVIATION...AC
MARINE...AC

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