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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS66 KMTR 171804 AAA
AFDMTR

Area Forecast Discussion...UPDATED
National Weather Service San Francisco CA
1104 AM PDT Wed Apr 17 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 154 PM PDT Tue Apr 16 2024

Warm, dry, and quiet this week as high pressure dominates. Onshore
flow and increased cloudiness late week as a weak trough moves
in.

&&

.SHORT TERM...
(Wednesday and Wednesday Night)
Issued at 1125 PM PDT Tue Apr 16 2024

High pressure at the surface and aloft will prevail across the
northeast Pacific. This will be the primary short-term influencer on
the weather regime across the Bay Area and Central Coast.
Temperatures early this morning are already fairly mild in the
thermal belts with readings in the 60s. And with plenty of sunshine
expect temperatures to climb rather quickly for most areas today.
Afternoon highs will generally reach the mid 70s to lower 80s for
most areas. The exception will be along the coastal interface and
within the marine-influenced valleys where a light onshore breeze
will keep temperatures in the mid 60s to around 70. There are some
vestiges of a very shallow marine layer along the coast so can`t
rule out some AM stratus or fog, but if it were to develop it should
mix out rather quickly after sunrise.

&&

.LONG TERM...
(Thursday through next Tuesday)
Issued at 1125 PM PDT Tue Apr 16 2024

After peaking on Wednesday the upper ridge will gradually lose
influence through late week in response to a weak perturbation
translating through the mean westerly flow. This wave will be
moisture-starved, so we`re not looking for any meaningful
precipitation, however we do expect more stratus, stronger
onshore flow, and cooler temperatures for Friday into the weekend.
It`s possible we could wring out a little orographically
influenced coastal drizzle, but confidence isn`t high enough to
include this in the forecast just yet.

Temperatures will cool a few degrees on Thursday, with a more
notable cooling (especially along the coast) by Friday.

The ridge rebuilds a bit over the weekend with a slight warming
trend. However onshore winds will keep things cooler by the coast.
Dry conditions should prevail.

&&

.AVIATION...
-- Changed Discussion --
(18Z TAFS)
Issued at 1033 AM PDT Wed Apr 17 2024

VFR will prevail through this evening with largely diurnal
breezes at all terminals. Tonight...MVFR and potentially IFR
ceilings and/or visibility is forecast at all terminals except LVK
and APC. Confidence is low to moderate in the ceiling/visibility
parts of the TAF.

Vicinity of SFO...VFR will prevail as the NE`ly SF Bay breezes
become more NW`ly through the afternoon. Speeds will range between
10-15 knots with moderate to high confidence in the winds
forecast. Winds subside below 5 knots around 04Z which may allow
for some flexibility for rwy configs. VFR cigs around FL200 will
continue to stream in overhead. Between 12-16Z, intermittent MVFR
cigs around FL025 are forecast as NE`ly SF Bay breezes return.
Confidence in MVFR is low to moderate. VFR is forecast to return
by 18Z Thu with NE`ly SF Bay breezes becoming NW`ly.

SFO Bridge Approach...MVFR cigs may obscure approach 11-18Z Thu.
Otherwise, similar to SFO.

Monterey Bay Terminals...VFR currently, however, the best
opportunity of IFR visibility and/or ceilings reside here.
Diurnal breezes under 15 knots are forecast to dominate through
the TAF period. The window in which the IFR probability (around
30-40%) peaks at MRY between 10-14Z with chances of IFR at SNS
under 20%. Intermittent MVFR cigs should lift by 15Z at SNS. VFR
is not forecast to return until after 18Z Thursday at MRY.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
(Today through Monday)
Issued at 1033 AM PDT Wed Apr 17 2024

Northerly wind gusts of 20 to 30 knots are forecast to continue
today before subsiding through the day on Thursday. Wind gusts on
Thursday will fall below 20 knots. Moderate period northwest swell
continues to move through the waters through the remainder of the
week. Longer period...18 seconds...southerly swell will also be
present through the week. This weekend will see a return to
increased northerly winds with near Gale force wind gusts forecast
late Saturday into Sunday in the wake of a cold front. Seas will
respond shortly thereafter with wave heights increasing to above
10 feet.
-- End Changed Discussion --

&&

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

     Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt
     to Pt Pinos 10-60 NM.
-- End Changed Discussion --

&&

$$

SHORT TERM...SPM
LONG TERM....SPM
AVIATION...Bain
MARINE...Bain

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