-- Discussion containing changed information from previous version are highlighted. --
286
FXUS66 KMTR 130559
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1059 PM PDT Wed Jun 12 2024

...New AVIATION...

.SYNOPSIS...
Issued at 1234 PM PDT Wed Jun 12 2024

Quiet through the rest of the week. Near normal temps by the
weekend. Increasing confidence for high wind potential and
increased fire danger Sunday into early next week.

&&

.UPDATE...
Issued at 856 PM PDT Wed Jun 12 2024

No changes to the forecast were require attm. Temperatures
will return to near normal for the end of the week through
the weekend. Gusty west/northwest surface winds will spread
across our area over the weekend into the beginning of next
week, with elevated fire weather concerns likely following
suit.

&&

.SHORT TERM...
(This evening through Thursday)
Issued at 1234 PM PDT Wed Jun 12 2024

Noticeably cooler temps today across the area as the upper level
ridge moves out and the marine layer deepens in response to a weak
mid level shortwave trough. Additionally, more robust marine
stratus associated with moisture from a weak disturbance off the
coast of southern CA will continue to linger for areas from around
Santa Cruz to the Big Sur coast. A few degrees warmer for
Thursday as the shortwave kicks out. Overall not much in the way
of impactful changes in the short term. Pleasant day ahead on
Thursday with little in the way of heat risk.

&&

.LONG TERM...
(Thursday night through next Tuesday)
Issued at 1234 PM PDT Wed Jun 12 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...
-- Changed Discussion --
(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.
-- End Changed Discussion --

&&

.MARINE...
(Tonight through next Monday)
Issued at 434 PM PDT Wed Jun 12 2024

Northwesterly winds persist over the northern waters through the
end of the week with gale force gusts possible over the northern
waters through early Thursday. Widespread strong northwesterly
winds with gale force gusts will build by the weekend and
continue into next week. 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 Thursday for Pt Arena to Pt
     Reyes 0-10 nm.

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

     Gale Warning until 9 AM PDT Thursday for Pt Arena to Pt Reyes 10-
     60 NM.

&&

$$

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

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