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000
FXUS66 KMTR 171947
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1247 PM PDT Wed Apr 17 2024

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

.SYNOPSIS...
Issued at 1206 PM PDT Wed Apr 17 2024

Warm temps persist into the weekend with a slight cool off Friday
as a weak trough pushes through. Increased cloudiness late week
with a chance of coastal drizzle. Otherwise seasonal going into
next week.

&&

.SHORT TERM...
(This evening through Thursday)
Issued at 1206 PM PDT Wed Apr 17 2024

Mostly clear conditions today with some highs clouds streaming
across the region. Not much change going into tomorrow. High temps
Thursday look to be pretty much on par with what is being seen
today, perhaps a couple of degrees cooler near the coast as the
ridge begins to break down.

&&

.LONG TERM...
(Thursday night through next Tuesday)
Issued at 1206 PM PDT Wed Apr 17 2024

Going into late Thursday, the high pressure ridge holding us
steady for the last few days begins to break down with the
approach of a weak trough embedded in the in the northwest flow.
Guidance has been fairly consistent in depicting this disturbance
as a weak, open wave that passes through fairly quickly. The main
effects will be a slight cooling of high temperatures for Friday
and increased cloud cover, especially for coastal areas. Overall
temps look to be about 3-5 degrees cooler on Friday than they were
on Thursday. The main factors here are increase onshore flow and
cloud cover. Deepening of the marine layer will also contribute to
a slight chance for patchy drizzle Friday and Saturday mornings,
especially near favored NW facing orographic areas near the coast.
Beyond Saturday, the ridge builds again going into the early part
of next week with temperatures remaining right around seasonal
normals. In the longer term, ensemble guidance advertises another
trough affecting the region by the middle of next week, but it is
unclear if this will be an efficient rain maker or not. Currently
about 25% of ensemble members reflect any measurable rain at all
for the area, so will need to wait for future forecasts to refine
any details.

&&

.AVIATION...
(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.

&&

.MARINE...
(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.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
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.

&&

$$

SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...Bain
MARINE...Bain

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