-- Discussion containing changed information from previous version are highlighted. --
654
FXUS66 KMTR 070600
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1100 PM PDT Mon May 6 2024

...New AVIATION...

.SYNOPSIS...
Issued at 124 PM PDT Mon May 6 2024

Seasonal temperatures to start the week with above normal temps
expected by Wednesday onward. Warm to end the week with minor Heat
Risk.

&&

.UPDATE...
Issued at 909 PM PDT Mon May 6 2024

Other than a few tweaks to the sky grids, the short term forecast
is in good shape. Nighttime GOES imagery reveals that marine
stratus has crept into western portions of the Bay Area and will
gradually invade parts of the East Bay, Santa Clara Valley,
Salinas Valley and Monterey Bay areas. The 00 UTC High Resolution
Rapid Refresh and a blend of other short-term guidance has
captured the evolution quite well and sky grids were updated to
account for these trends. VWP and data from our evening sounding
does suggest some potential for interior fog development across
San Benito County, but I anticipate this to be confined to the
most sheltered locations as 925mb winds still appear a bit
elevated (10-15 knots) to prevent the PBL from decoupling
completely. If winds are lighter than forecast, then the fog
potential will increase substantially.

There are signals (40-60% probabilities of visibility below 1
mile) of a greater fog threat across marine zones adjacent to the
Santa Cruz County and Monterey County shorelines this evening and
the forecast mentions this in the worded products. The chance for
fog across the land areas (e.g. SF Peninsula) diminish, though
remain around 20%...so we`ll have to monitor overnight. At this
time, low level flow (again around 10-15 knots) should favor more
in the way of low stratus than reduced visibility.

Otherwise, this week is shaping up to be rain-free, but warm.
We`ll have more details on the late week heat later tonight/early
Tuesday morning.

&&

.SHORT TERM...
(This evening through Tuesday)
Issued at 124 PM PDT Mon May 6 2024

Another mostly clear day across the area with some high clouds
streaming through and some shallow cumulus over terrain in a few
of the coastal ranges. Similar to days previous, sufficient mid-
level stability will prevent anything interesting from happening
with the cumulus. Coming off of a chilly morning today,
temperatures will be near seasonal averages the next couple of
days, warming gradually. Really not much else to talk about in the
short term, as it look like a very pleasant couple of days with
little weather risk.

&&

.LONG TERM...
(Tuesday night through next Sunday)
Issued at 124 PM PDT Mon May 6 2024

By Wednesday, high temps will be above average with afternoon
highs nearing 80 for inland areas. This trend will continue into
the weekend. Thursday and Friday look to be the warmest days where
inland locations could see their first 90 degrees of the year.
Most other will see temps in the 80s, while coastal locations will
be in the 70s. A bit of uncertainty in regard to the high temp
forecast for areas near the coast and bay shoreline, including San
Francisco. It appears we`ll have a moderate push of offshore winds
for inland areas late Wednesday into Thursday morning. We aren`t
expecting these onshore winds to completely erode the marine layer
like some strong events we see in the fall, but they could prove
to make Thursday`s high temp forecast difficult, especially for SF
and the east and north bay shorelines. Current forecast for these
areas Thursday is the upper 70s to lower 80s, but these temps may
need to be nudged upwards in the event we expect the offshore
component to last longer into Thursday. In regard to the offshore
winds, it appears to be a fairly short event (<1 day), and any
drying that occurs is not expected to reach critical levels.
Inland areas will see very limited RH recovery going into
Thursday, but should bounce back by Friday morning and into the
weekend as winds return to onshore. Guidance brings temps down
slightly into the weekend, but still above normal. All in all
should be a very nice second half of the week for everyone. That
being said, folks should still exercise caution when enjoying time
outdoors as this swing from below normal to above normal
temperatures can catch people off guard. Plan to pack some extra
water and sun protection if you`re planning to spend time
outdoors. And the most important preparation if you`re going to
the coast or relaxing poolside...SUNSCREEN!!!

&&

.AVIATION...
-- Changed Discussion --
(06Z TAFS)
Issued at 1059 PM PDT Mon May 6 2024

In the overnight hours tonight and into Tuesday morning, low clouds
will bring MVFR/IFR conditions to a select few terminals, but
otherwise widespread VFR is expected. Onshore winds continue to ease
at this hour and will do so throughout the night. Terminals around
the greater SF Bay will see low clouds intermittently bringing MVFR
conditions, however, this is expected to cease towards sunrise, with
VFR conditions returning as clouds mix out. Further south towards
Monterey Bay, IFR CIGs are expected to develop and last through
sunrise. Northwest winds increase in the afternoon Tuesday to become
moderate once more, gusting to around 20-25 knots for terminals near
coastal gaps.

Vicinity of SFO...Intermittent MVFR conditions are expected as low
clouds persist around the terminal. Have included a TEMPO in the
TAF to reflect the intermittent nature of MVFR CIGs tonight.
Otherwise, VFR is expected to return Tuesday morning right around
sunrise, to perhaps just beyond. VFR then lasts through the
remainder of the TAF period with gusty NW winds building in the
afternoon and lasting through the early evening of Tuesday.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...MVFR/IFR conditions last through sunrise as
low clouds build around the terminal, but clear to become VFR
shortly after. VFR lasts through the remainder of the TAF period.
Breezy northwest winds expected in the afternoon of Tuesday once
more, then easing into the evening to become light.
-- End Changed Discussion --

&&

.MARINE...
(Tonight through next Sunday)
Issued at 909 PM PDT Mon May 6 2024

Dry weather to continue through next weekend. West to
northwesterly  winds will gradually transition northerly overnight
tonight into  Tuesday. As the high pressure system continues to
build and move  eastward, winds will strengthen starting Tuesday
with gale force  gusts Tuesday night through Wednesday night with
the strongest gusts  located along the Big Sur Coast and northern
outer coastal waters. Significant wave heights will build to
heights to 15 to 16 feet by  mid-week. Conditions will be
extremely hazardous for all but the  largest vessels Tuesday and
Wednesday and extreme caution should be  exercised during this
time.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM to 9 PM PDT Tuesday for Mry Bay.

     Small Craft Advisory from 3 AM Tuesday to 3 AM PDT Wednesday for
     Pt Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory from 9 AM Tuesday to 3 AM PDT Wednesday for
     Pigeon Pt to Pt Pinos 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

     Small Craft Advisory until 3 AM PDT Tuesday for Pt Pinos to Pt
     Piedras Blancas 0-10 nm.

     Gale Warning from 3 AM Tuesday to 3 AM PDT Wednesday for Pt
     Pinos to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory from 3 AM to 3 PM PDT Tuesday for Pigeon Pt
     to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.

     Gale Warning from 3 PM Tuesday to 3 AM PDT Wednesday for Pigeon
     Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.

&&

$$

SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...AC
MARINE...SO

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