-- Discussion containing changed information from previous version are highlighted. --
868
FXUS66 KMTR 252127
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
227 PM PDT Tue Jun 25 2024

...New SYNOPSIS, SHORT TERM, LONG TERM...

.SYNOPSIS...
-- Changed Discussion --
Issued at 220 PM PDT Tue Jun 25 2024

Chances for elevated thunderstorms continue across the Bay Area
through this evening with chances diminishing by evening. Cooler,
seasonal to below average temperatures return Wednesday and
persist through the end of the week.
-- End Changed Discussion --

&&

.SHORT TERM...
-- Changed Discussion --
(This evening through Wednesday)
Issued at 220 PM PDT Tue Jun 25 2024

Slight (10-15%) chance of thunderstorms producing dry lightning
continues over the Bay Area before chances diminish by the late
evening. Radar continues to show elevated cells moving over
Sonoma, Napa, and Marin Counties with the potential for isolated
thunderstorms continuing into the evening hours. For lightning
activity so far today, several strikes occurred in the vicinity of
the San Jose and Livermore airports this morning. Three airports
(San Francisco, Livermore, and San Jose) observed trace
precipitation overnight and again this morning, indicating some
precipitation is making it to the surface. However, precipitation
totals greater than a few hundredths of an inch are not
anticipated as most precipitation is expected to evaporate before
reaching the ground (creating a neat phenomenon known as virga).
Remember to stay weather aware and when thunder roars, go indoors!

Tuesday continues to be the warmest day this week with temperatures
cooling down beginning Wednesday. Tonight`s overnight low
temperatures, both inland and along the coast, will range from the
low to upper 50`s. Upper level troughing will move inland tonight
into tomorrow with temperatures cooling down to seasonal to slightly
below average. Wednesday`s inland high temperatures are expected to
be 3 to 7 degrees cooler than today`s with most areas seeing highs
in the upper 70`s to mid 80`s. Favored inland hot spots may see
temperatures reach the upper 80`s. Closer to the coast, cooler
temperatures prevail with highs largely in the upper 50`s to mid
60`s. As upper level troughing moves inland, the marine layer is
expected to deepen with increasing stratus chances along the
coastline and portions of the San Francisco Bay.
-- End Changed Discussion --

&&

.LONG TERM...
-- Changed Discussion --
(Wednesday night through next Monday)
Issued at 220 PM PDT Tue Jun 25 2024

Upper level troughing will persist through late week with seasonal
to below average temperatures similar to Wednesday (upper 70`s to
mid 80`s inland and upper 50`s to mid 60`s along the coast)
continuing through Saturday. However, by Sunday, guidance continues
to indicate a warming trend will develop as upper level ridging
again builds over the West Coast. While this forecast is several
days out and subject to revision, here is a preview of what the
warming trend currently looks like. By Sunday, inland temperatures
will gradually warm into the upper 80`s to low 90`s before reaching
into the low to mid 90`s on Monday and low to upper 90`s on Tuesday.
While outside of this forecast period, longer term guidance suggests
that these warmer temperatures will prevail through most of next
week. For those along the coast, temperatures will warm into the
60`s to low 70`s beginning Sunday through the end of the forecast
period.
-- End Changed Discussion --

&&

.AVIATION...
-- Changed Discussion --
(18Z TAFS)
Issued at 1059 AM PDT Tue Jun 25 2024

High-level clouds with a few embedded storm cells are moving across
the region through the region. Chances for storms linger into the
evening but more of the focus will be to the north and east of the
region. Expect breezy conditions through the afternoon that ease into
the evening. As winds reduce, IFR/MVFR CIGs begin to move inland
affecting the Monterey Bay TAF sites this evening, with OAK and SFO
affected late into the night. Winds stay light to moderate through
Wednesday morning, with CIGs dissipating in the mid to late morning.
Expect widespread VFR by Wednesday afternoon with gusty and breezy
winds.

Vicinity of SFO...Broken high-level clouds become scattered into the
evening and exit overnight. Winds become breezy this afternoon with
gusts around 22 kts. Winds reduce into the night with MVFR CIGs
filling over the terminal. These CIGs erode into mid Wednesday
morning with gustier west winds arriving into Wednesday morning.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VF lasts into the evening with passing high
clouds. Moderate to breezy westerly winds build this afternoon.
Winds reduce into the evening as IFR CIGS move inland and fill over
MRY, with SNS filling later into the night. CIGS erode in the mid to
late morning on Wednesday as moderate to breezy winds arrive.
-- End Changed Discussion --

&&

.MARINE...
(Today through Sunday)
Issued at 1059 AM PDT Tue Jun 25 2024

Moderate to breezy northwesterly continue. Stronger northwesterly
breezes arrive into Wednesday morning creating hazardous
conditions for small crafts across all the waters. Significant
wave heights will continue to abate below 10 feet through the
period.

&&

.FIRE WEATHER...
Issued at 315 AM PDT Tue Jun 25 2024

There is a slight chance of thunderstorms this afternoon, with
limited coverage. Given the elevated nature of any storms that
may develop, any rainfall amounts, if any, will be light with
some VIRGA possible and subsequent gusty winds. Any strikes that
do occur may cause a fire start in the fine fuels.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CA...None.
PZ...Small Craft Advisory from 3 PM to 9 PM PDT Wednesday for Mry Bay.

     Small Craft Advisory from 9 AM Wednesday to 3 AM PDT Thursday
     for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-
     10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory from 3 PM Wednesday to 3 AM PDT Thursday
     for Pt Arena to Pt Reyes 10-60 NM-Pt Reyes to Pigeon Pt 0-
     10 nm.

     Small Craft Advisory from 9 AM to 9 PM PDT Wednesday for Pigeon
     Pt to Pt Pinos 0-10 nm.
-- End Changed Discussion --

&&

$$

SHORT TERM...Kennedy
LONG TERM....Kennedy
AVIATION...Murdock
MARINE...Murdock

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