084
FXUS66 KMTR 201618
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
918 AM PDT Fri Sep 20 2024

...New UPDATE, MARINE...

.SYNOPSIS...
Issued at 350 AM PDT Fri Sep 20 2024

Warmer temperatures today mark the beginning of a steady warming
trend that will persist through the weekend into the beginning of
next week. Moderate heat risk conditions are still possible for many
interior locations Monday and Tuesday, but forecast trend has been
slightly cooler.

&&

.UPDATE...
Issued at 912 AM PDT Fri Sep 20 2024

Stratus is just starting to break up across the region, with the
interior East Bay and the Carmel Valley clearing out the most
visibly on satellite imagery. Some coastal drizzle was observed
earlier this morning, with accumulations ranging from a trace to a
few hundredths of an inch. Progressive clearing of stratus is
expected inland with the immediate coast and parts of Monterey Bay
remaining socked in through the day. No updates to the forecast at
this time.

DialH

&&

.SHORT TERM...
(Today and tonight)
Issued at 350 AM PDT Fri Sep 20 2024

Low stratus clouds have filled in along the coastline and interior
gaps and valleys overnight and will begin to erode by mid/late
morning except along the immediate coastline, especially Monterey
Bay, where the marine boundary layer is reestablished with light
onshore flow throughout the day. Gradual but steady H50 height
increases in the wake of the upper low moving inland over SOCAL this
afternoon will lift temperatures up about 5 degrees over inland
locations from yesterdays high temperatures. High pressure continues
to build offshore tomorrow, driving temperatures warmer on Saturday
to around normal values for this time of year.

&&

.LONG TERM...
(Saturday through Thursday)
Issued at 350 AM PDT Fri Sep 20 2024

Temperatures will gradually warm through the weekend into the
beginning of next week. The forecasted max temperatures have trended
slightly cooler but moderate heat risk across many inland locations
Monday and Tuesday may still lead to the need for a Heat Advisory
for those two days. There is poor consensus for the evolution of the
synoptic pattern west of the Rockies for the first half of next
week, as a weak upper level low develops off the coast of SOCAL.
Nonetheless, temperatures moderate somewhat for the second half of
next week from Monday and Tuesdays peak. We appear to remain dry
through the extended forecast after some welcomed rainfall over
southern Monterey County yesterday.

&&

.AVIATION...
(12Z TAFS)
Issued at 404 AM PDT Fri Sep 20 2024

Stratus and fog /VLIFR-IFR-MVFR/ are moving inland on onshore winds
this morning. Stratus and fog mixing out back to near the coast and
bays by late morning and afternoon today.

Vicinity of SFO...IFR prevailing to 1700z today, MVFR 1700z to 1830z
today then VFR. IFR returning late tonight. West to southwest wind
5 to 15 knots.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VLIFR-IFR due to stratus and fog this morning,
conditions improving to MVFR-VFR by late morning and afternoon today.
MVFR-IFR in stratus and fog returning tonight. Onshore winds mainly
5 to 15 knots.

&&

.MARINE...
(Today through Wednesday)
Issued at 912 AM PDT Fri Sep 20 2024

Moderate northwesterly winds continuing through Monday, then
decrease to become gentle towards Tuesday. Seas will continue to
build through the weekend, with wave heights up to 13 feet in the
far northern outer waters as large, and shorter period
northwesterly swell continues to move into the waters. Seas begin
to abate Tuesday through the end of the forecast period.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 PM PDT Saturday for Pt Arena to Pt
     Reyes 10-60 NM.

&&

$$

SHORT TERM...JM
LONG TERM....JM
AVIATION...Canepa
MARINE...AC

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