-- Discussion containing changed information from previous version are highlighted. --
011
FXUS66 KMTR 032016
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
116 PM PDT Fri May 3 2024

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

.SYNOPSIS...
-- Changed Discussion --
Issued at 1237 PM PDT Fri May 3 2024

Cold front on track to bring widespread rain, cooler temperatures,
and gusty winds this weekend. Dry weather returns Sunday with a
gradual warming trend through next week.
-- End Changed Discussion --

&&

.SHORT TERM...
-- Changed Discussion --
(This evening through Saturday)
Issued at 1237 PM PDT Fri May 3 2024

Mostly clear skies over the region today ahead of the next cold
front. Ample cloud cover associated with the front now moving into
the northern portions of the state will continue to move southward
through tonight. Areas of light rainfall are expected to begin
early Saturday morning along favored west-facing upslope areas
in the coastal ranges as moist low-level westerly flow increases
ahead of the front. Much of the surface front should be through
the Bay Area by mid-morning, and late morning for areas further
south along the Central Coast. Aided by a robust 150 kt NW-SE
oriented jet on the back side of the low, this will be a rather
quick-moving front with little-to-no chance of stalling. However,
this jet and continued support of an enhanced northwesterly Eastern
Pacific jet along the West Coast will support gusty northwest
winds to 25-35 mph along coastal areas and NW-SE oriented valleys
through the weekend. Rainfall amounts Saturday will be in the ball
park of 0.4-0.75" for most locations, with a few seeing upwards of
1-1.25" in the coastal ranges of the North Bay and the Santa Cruz
Mtns.

Behind the cold front Saturday afternoon and evening, there is a
slight chance for isolated thunderstorms across the area.
Scattered showers will persist into Saturday evening, but
conditions appear favorable for a few locally strong updrafts that
would support a rumble of thunder or two, as well as small hail.
Deep convection would not be supported, given limited cooling
aloft, promoting a more stable environment aloft. Thus, any storms
that do develop would be relatively short-lived. Really nothing
out of the ordinary for us during these typical cold core systems,
just more resemblant of a system we`d see in January rather than
May.
-- End Changed Discussion --


&&

.LONG TERM...
-- Changed Discussion --
(Sunday through next Thursday)
Issued at 1237 PM PDT Fri May 3 2024

Sunday looks to be on the drier side with the low departing.
Temperatures the next few days will be on the cool side with
afternoon high temps dropping by as much as 18 degrees for inland
locations. Low temps Sunday morning will be in the 40s for most,
with a few pockets of upper 30s for inland and high elevation
areas. Otherwise, a warm up is on tap for the rest of next week as
the pattern becomes more ridge-dominant. By Wednesday, expect
afternoon highs in the 70s to near 80, and the mid-to-upper 60s
along the coast.
-- End Changed Discussion --

&&

.AVIATION...
(18Z TAFS)
Issued at 1126 AM PDT Fri May 3 2024

VFR prevails through the daytime today, though stratus makes a
return in the early to mid evening for most terminals, bringing
largely IFR/LIFR conditions as ridging continues to squash cloud
decks. Winds generally W/NW and strong today, with gusts around 20-
25 knots, higher at SFO. As stratus approaches in the evening, winds
ease, but remain close to 10 knots through much of the night, and
slowly turn to become more S/SW ahead of the approaching low
pressure system. By the mid morning hours of Saturday, most
terminals will see winds increase once more to become breezy and
gusty out of the SW, and rain begins, lowering visibilities at
terminals. Cloud decks are expected to improve to become MVFR around
the same time to slightly after when rain approaches as greater
lifting from associated low pressure is enabled. Rain continues
through the end of the TAF period for most terminals, with winds
turning to become N/NW and breezy.

Vicinity of SFO...VFR conditions last through the afternoon today,
with strong and gusty onshore winds. Max gusts up to 35 knots are
expected. Stratus makes an early return in the evening, bringing IFR
conditions. Models suggest a reduction to LIFR conditions in the
overnight hours, but at this time, confidence in that development
is low. Have kept CIGS IFR and then improving to MVFR in the later
morning for now. Rain and gusty SW winds begin just prior to
sunrise Saturday for KSFO. Winds turn to become W/NW in the later
morning, but rain lasts through the afternoon.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Conditions improve to VFR in the early
afternoon today, though only for a few hours before stratus and
IFR/LIFR CIGs make a quick push inland in the early evening. Winds
NW and breezy this afternoon, but easing into the evening to below
10 knots. IFR/LIFR CIGs last through the majority of the overnight
hours. Towards the late morning of Saturday, rain begins and CIGs
lift to become IFR. Some model solutions hint at CIGs lifting enough
to become MVFR by the end of the TAF period. However, confidence in
this outcome is low at this time. For now, have left CIGs as
lifting, but remaining in IFR through the end of the TAF period.

&&

.MARINE...
(Today through Wednesday)
Issued at 457 AM PDT Fri May 3 2024

Strong and gusty northwesterly winds will persist for yet another
day as the region remains in between high pressure over the
Eastern  Pacific Ocean and low pressure over the Southwest. Gale
force gusts  will be possible, especially over the coastal waters
and  southernmost zones. Tonight, a cold front will drop down from
the  Pacific Northwest bringing rain and moderate to fresh breezes
across  the waters. As the low pressure system exits to the east
and the  pressure gradient is allowed to relax, winds will
diminish going  into next week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT this evening for Mry Bay-
     Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60
     NM-Pt Arena to Pt Reyes 0-10 nm-Pt Reyes to Pigeon Pt 0-10
     nm.

     Gale Warning until 3 AM PDT Saturday for Pt Pinos to Pt Piedras
     Blancas 0-10 nm.

     Small Craft Advisory until 3 PM PDT this afternoon for Pt Arena
     to Pt Reyes 10-60 NM.

     Small Craft Advisory from 3 AM to 9 AM PDT Saturday for Pt Arena
     to Pt Reyes 10-60 NM.

&&

$$

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

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