846
FXUS66 KMTR 170630
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1130 PM PDT Mon Sep 16 2024

...New AVIATION...

.SYNOPSIS...
Issued at 1203 PM PDT Mon Sep 16 2024

Rain showers will taper off from north to south through this evening
with temperatures remaining below seasonal averages through late
week. Another system enters the picture Wednesday with additional
rain chances, however rainfall amounts will be light. Warming into
the weekend.

&&

.UPDATE...
Issued at 852 PM PDT Mon Sep 16 2024

Showers have tapered off this evening. We generally received a
few hundredths of an inch in the East Bay and most populated
valleys, around 1/10" in the Santa Cruz Mountains, and around 1/4"
in the Santa Lucia mountains. Skies have cleared in the North
Bay, and that could lead to some fog formation overnight. We would
have more confidence if the North Bay got any rain earlier, but
100% humidity, light winds, and clear skies could bring some
shallow fog.

&&

.SHORT TERM...
(This evening through Tuesday)
Issued at 1203 PM PDT Mon Sep 16 2024

Isolated rain showers continue over the region early this afternoon
and are expected to diminish in coverage while shifting southward
through this evening. Tonight, coastal drizzle will be possible as
moist conditions persist and troughing lingers over the region.
Temperatures overnight will be in the upper 40`s (in the coldest
interior spots) to mid 50`s for much of the region.

Tomorrow, temperatures will remain 5-15 degrees below average.
Outside coastal drizzle in the morning, tomorrow will be dry with
partial clearing of sky conditions through the afternoon.

&&

.LONG TERM...
(Tuesday through Sunday)
Issued at 154 AM PDT Mon Sep 16 2024

The next system set to come through Wednesday looks to be
very similar, but with slightly less of a wind threat. Still
looking at breezy winds in the same areas early Wednesday morning,
but more on the order of 25-35 mph as opposed to the 45-50 mph we
saw over the last 24 hours. A bit of a better chance for thunder
with the Wednesday system as well. Still a low chance (~15%), but
with a bit more cooling aloft and more lower level moisture, there
is more widespread instability late Tuesday night going into
Wednesday morning. Rain amounts still look to be on the lower
side, if any, similar to today. Beyond Wednesday there really
isn`t much noteworthy to write about. A casual warm up is on tap
going into the weekend that will bring our temperatures to around
seasonal normals. By the end of the weekend, there is some
discrepancy in ensemble guidance regarding the strength of a
possible ridge pattern. More on that in the coming days.

&&

.AVIATION...
(06Z TAFS)
Issued at 1129 PM PDT Mon Sep 16 2024

IFR and MVFR CIGs build through the night last into the mid to late
morning for most TAF sites, but last longer for coastal areas and
around the Monterey Bay. Pockets of drizzle and mist will affect the
coast as well as the Bays and STS in the late night through much of
the morning. Winds stay light to moderate through the morning.
Widespread VFR returns for the TAF sites into Sunday afternoon, but
status lingers on the immediate coast. Expect moderate winds to
build into the afternoon and linger into the evening. Coastal cloud
cover moves slightly early Tuesday evening, affecting SNS and MRY
with IFR and MVFR CIGS becoming widespread later that night.

Vicinity of SFO...IFR CIGs build into the late night and last into
the late morning with some mist and pockets of fog in the area.
Expect light to moderate winds overnight. CIGs erode as winds build
in the late morning. Wind gusts will reduce slightly into Tuesday
evening as MVFR CIGs return.


SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...MVFR/IFR CIGs  with mist and drizzle last
through the late morning. Expect visibilities to improve in the late
morning as CIGs scatter and winds become more moderate. IFR CIGs
return early Tuesday evening as winds reduce.

&&

.MARINE...
(Tonight through next Sunday)
Issued at 852 PM PDT Mon Sep 16 2024

Northwest winds continue to gradually decrease overnight in the
wake of yesterday`s cold front. Small craft warnings remain in
effect in the NW waters mainly for wind gusts more than 45 NM from
the coast. Rough seas are gradually abating in the NW waters and
will continue through the next 24 hours. There is a bit of a
break on Tuesday before a second cold front brings the return of
strong NW winds and rough seas to the exposed coastal waters.

&&

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

&&

$$

SHORT TERM...RGass
LONG TERM....Behringer
AVIATION...Murdock
MARINE...Flynn

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