633
FXUS66 KMTR 070425 AAA
AFDMTR

Area Forecast Discussion...UPDATED
National Weather Service San Francisco CA
925 PM PDT Mon May 6 2024

...New UPDATE, MARINE...

.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...
(00Z TAFS)
Issued at 442 PM PDT Mon May 6 2024

VFR through the TAF period for all terminals. Some models
suggest MVFR ceilings for some terminals overnight, but had low
confidence to include in TAFs at this moment and was indicated with
a SCT group. Breezy to strong W/NW will diminish overnight and
rebuild to breezy by Tuesday afternoon.

Vicinity of SFO...VFR through the TAF period. Breezy westerly winds
will becoming moderate overnight but will rebuild to breezy by
Tuesday afternoon. Models do hint at MVFR cigs building this evening
into the morning. With low confidence and model disagreement, a
SCT group was placed in TAFs to maintain VFR conditions at this
moment.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...High confidence that VFR will persist
through the evening, but models hint at MVFR conditions tonight into
the morning. With low to moderate confidence that stratus will build
to MVFR levels, a SCT group was placed to hint at the possibility of
low CIGs, and will continue to monitor for any needed amendments.

&&

.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.

&&

$$

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

Visit us at www.weather.gov/sanfrancisco

Follow us on Facebook, Twitter, and YouTube at:
www.facebook.com/nwsbayarea
www.twitter.com/nwsbayarea
www.youtube.com/nwsbayarea