-- Discussion containing changed information from previous version are highlighted. --
561
FXUS66 KMTR 191810
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1110 AM PDT Wed Jun 19 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 155 PM PDT Tue Jun 18 2024

Upper level trough will dig over California through midweek, with
breezy onshore winds continuing and temperatures near seasonal
averages prevailing through Thursday. The trough will remain in
place, but weaken for Friday and the weekend, with warmer
conditions developing once again across the inland areas.

&&

.SHORT TERM...
(Today and tonight)
Issued at 102 AM PDT Wed Jun 19 2024

Generally clear so far tonight with some patchy stratus near Half
Moon Bay and around the southern Monterey Bay region. An upper level
trough is digging into the region, helping to promote an expanding
marine layer today. Low temperatures this morning range from the mid
40s to the mid 50s across the lower elevations, perhaps near 60 in
the higher elevations. High temperatures are expected to cool a few
degrees from yesterday across most of the region, helped by breezy
onshore flow this afternoon. High temperatures range from the mid
50s to lower 60s along the coast, the mid 60s to lower 70s in the
Bayshore, and the upper 70s to mid 80s in the inland valleys.

&&

.LONG TERM...
(Thursday through Tuesday)
Issued at 102 AM PDT Wed Jun 19 2024

Thursday should be a little warmer across the region as the upper
level trough begins to erode and fill in, with temperatures in the
inland regions rising by a few degrees. More dramatic warming is
expected by Friday as the trough continues to erode, and a ridge
begins to build across the Intermountain West. The warmest
temperatures are expected on Saturday, where highs will range from
the 90s to lower 100s for the inland regions, the mid 70s to low 80s
for the Bayshore, and the low to mid 60s for the coast. Model
ensembles suggest that the ridge stays in place through the early
part of next week, with warm conditions continuing inland. CPC
outlooks suggest that temperatures above seasonal averages, and
precipitation around or below the seasonal average, continue into
the beginning of July.

&&

.AVIATION...
-- Changed Discussion --
(18Z TAFS)
Issued at 1109 AM PDT Wed Jun 19 2024

VFR through the afternoon for terminals with breezy onshore winds
generally out of the W/NW. Not expecting much in the way of gusts
this afternoon at coastal terminals like previous days, though the
occasional gust cannot be ruled out. Stratus begins to push inland
in the early evening for Monterey and SF bay terminals, bringing
MVFR CIGs that last through sunrise of Thursday.

Vicinity of SFO...VFR through the early evening today with moderate
W/NW winds, gusts nearing 25 kt possible. Stratus returns in the
evening as winds begin to ease. MVFR CIGs are expected to last
through sunrise Thursday morning. A few models suggest CIGs
lowering overnight to become IFR, however, highest confidence is
in CIGs maintaining MVFR through the night.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR lasts through the early evening.
Towards the 03-06Z timeframe, expecting stratus to begin advecting
inland bringing MVFR CIGs. Moderate confidence on CIGs lowering to
become IFR in the early morning of Thursday, as dry air aloft
(visible in Wednesday KOAK 12Z sounding) may help to compress and
"sink" the cloud layer. Regardless, stratus and low CIGs persist
through the late morning of Thursday. Clearing to VFR is not
expected until well beyond sunrise.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
(Today through Monday)
Issued at 1109 AM PDT Wed Jun 19 2024

  Northwest winds increase again late this afternoon across the
northern waters, remaining gusty through the weekend and into the
next work week. Significant wave heights stay around 6-8 feet,
will build back up to 10-12 feet towards the end of the the
weekend as larger northwesterly swell returns.
-- End Changed Discussion --

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CA...None.
PZ...Small Craft Advisory from 3 PM Thursday to 3 AM PDT Friday for
     Pt Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory from 9 PM this evening to 3 AM PDT Friday
     for Pt Arena to Pt Reyes 10-60 NM.
-- End Changed Discussion --

&&

$$

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

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