| |
|
NWS Technical
Weather Discussion |
|
|
FXUS66 KMTR 131912
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1212 PM PDT Sat Jun 13 2026
...New AVIATION...
.KEY MESSAGES...
Updated at 1201 AM PDT Sat Jun 13 2026
- Continued hot and dry today for interior communities with Moderate
HeatRisk.
- Minor coastal flooding due to higher than normal high tides
anticipated across coastal regions of the San Francisco Bay
Area and Central California Coast.
- Hazardous beach conditions return by Sunday with increased risk
of sneaker waves and strong rip currents.
&&
.UPDATE...
Issued at 940 AM PDT Sat Jun 13 2026
The short term forecast is on track, no changes anticipated.
Overcast conditions that blanketed the area overnight is beginning
to clear out of the inner coastal valleys such as San Jose and
Salinas. Clearing will continue this morning over land returning
to the marine environment by around 12 PM PDT. Warm temperatures
on track again today for Santa Clara Valley and eastern counties
such as Alameda and Contra Costa with a moderate risk for heat
related illnesses.
&&
.SHORT TERM...
Issued at 1201 AM PDT Sat Jun 13 2026
(Sunday night through next Friday)
Overcast conditions are blanketing the entire Pacific coast along
Sonoma County through Monterey County this early Saturday morning.
The stratus has spilled through the Golden Gate, and is also
expanding through the Salinas Valley. Nearly all airports are
running cooler compared to this time 24 hours ago throughout the
region, including inland terminals such as Livermore and Concord.
The healthy onshore gradient of +3.4 mb from SFO to SAC will help
expand the stratus as he night progresses.
Upper-level ridge remains over the eastern Pacific with northwest
flow aloft prevailing over the Golden State. For this afternoon,
expect seasonable temperatures along the immediate Pacific coast
with temperatures in the 60s and 70s, while communities away from
the oceanic influence will be much warmer in the 80s to near 100
degrees for far inland locations. While there will be a few
degrees of cooling realized today, HeatRisk for the interior East
Bay and South Bay will remain in the Moderate category. As a
result, a Heat Advisory continues for these locations through 7 PM
PDT this evening.
High tide flooding will continue to occur nightly along the low-
lying areas of the Bayshore and the Pacific Coast through the
middle of next week. The combination of an upcoming new moon and
lunar perigee on Sunday, about 7 inches of additional tidal
anomaly from a combination of storm surge, thermal expansion of
the Eastern Pacific, and about 2 inches inches of Sea Level Rise
since the vertical datums were established in the 80s and 90s will
add up to bring tides up to 2.0 feet above normal through early
next week. While lower than the historic tidal flooding in January
(peaked at 2.6 ft) the tides this weekend could end up being the
highest observed in the Summer, beating the current record of 1.7
ft from July 2022.
&&
.LONG TERM...
Issued at 1201 AM PDT Sat Jun 13 2026
(Sunday night through next Friday)
By Sunday and Monday, the grasp of the eastern Pacific ridge will
fade as it flattens, courtesy of an Aleutian low. The end result
for us will be a subtle (and welcomed) day-to-day cooling for
interior communities and the usual June stratus along the Pacific
Coast. The ridge will attempt to rebuild around Tuesday/Wednesday,
which may mark the end of the cooling trend for inland areas.
&&
.AVIATION...
(18Z TAFS)
Issued at 1205 PM PDT Sat Jun 13 2026
Stratus and fog impacted the coastal and Bay Area terminals this
morning. Daytime heating has allowed for that to burn off with the
marine layer retreating as well. Some of the inland terminals
also were impacted, such as KSTS, KAPC, and KSNS. VFR conditions
will continue through the afternoon and into the evening hours
before the marine layer pushes back inland bringing stratus and
fog back to the region. High resolution modeling continues to
show coastal stratus and fog (IFR-LIFR) to redevelop tonight and
tomorrow morning. Similar conditions from this morning are
expected again tomorrow morning. Winds will follow similar
patterns to the past 24 hours with speeds increasing to moderately
breezy this afternoon, but diminishing around sunset.
Vicinity of SFO...Similar conditions from the past 24
hours are expected for the next 24 hours. High confidence of VFR
conditions continuing into the overnight hours. Current NE winds
will go NW'rly early this afternoon (~20Z). Wind speeds will
increase into the middle teens this afternoon, but subside back
below 10 kt around or shortly after sunset. Winds will then go
westerly early tomorrow morning before going N/NE by the middle
of tomorrow morning. Radiative cooling may result in some
additional areas of patchy low stratus/fog developing during the
overnight/morning hours tomorrow.
SFO Bridge Approach...Similar to SFO.
Vicinity of SJC and OAK...Similar conditions from the past 24
hours are expected for the next 24 hours. Winds will
predominately be out of the W/NW at OAK through the period. Winds
at SJC will be out of the NW through this evening before going
S/SE during the overnight hours. Wind speeds, at both sites, will
be in the low to mid teens this afternoon through sunset,
otherwise winds will be aob 8 kt. For OAK, morning stratus/fog
(IFR) is expected to redevelop tonight and tomorrow morning,
otherwise VFR conditions are expected. At SJC, stratus is expected
to start impacting the terminal during the overnight hours
(starting ~09Z), however CIGs are not expected to develop with
this stratus over the terminal and VIS is not expected to
decrease.
Monterey Bay Terminals...Similar conditions from the past 24
hours are expected for the next 24 hours. Stratus/fog from earlier
this morning has burned off with diurnal surface heating allowing
for conditions to improve to MVFR-VFR. Stratus/fog (IFR/LIFR) is
expected to redevelop and move inland tonight and tomorrow
morning. The stratus and fog is expected to start to impact the
Monterey Bay terminals as early as 03Z. Winds will be light and
variable (but will tend to be more onshore winds) through the
majority of the period. W/NW winds are expected to increase to
7-13 kt this afternoon, then subside around sunset.
&&
.MARINE...
(Today through Thursday)
Issued at 852 AM PDT Sat Jun 13 2026
A gentle southerly breeze and moderate to rough seas with a low
south southwest swell persist across most of the coastal waters.
Fresh to strong breezes will be possible along the Big Sur coast
through this evening. Winds will remain fairly consistent through
the weekend as the seas subside.
&&
.BEACHES...
Issued at 404 AM PDT Sat Jun 13 2026
Long period southerly swell will continue through the weekend,
especially for south and southwest facing beaches. Hazardous beach
conditions are advertised, specifically for moderate to steeply
sloped beaches along the Pacific Coast of the North Bay, San Mateo,
Santa Cruz counties. A Beach Hazards Statement is in effect for
Pacific coast beaches along the central coast and the Bay Area
coast from late tonight through late Tuesday night. Be sure check
beach conditions before you head out. Sneaker waves will run up
the beach much farther than other waves, potentially catching
beachgoers by surprise and resulting in people being swept into
the water. Rip currents are strong enough to pull the strongest
swimmers away from shore. Swim near a lifeguard if possible. Stay
back from the beach, and away from jetties, piers, beachside
rocks, and other infrastructure near the water. Never turn your
back to the ocean!
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory until 3 AM PDT Wednesday for CAZ006-506-
508.
Beach Hazards Statement from late tonight through late Tuesday
night for CAZ006-505-509-529-530.
Coastal Flood Advisory from 7 PM this evening to 3 AM PDT
Tuesday for CAZ505-509-529-530.
Heat Advisory until 7 PM PDT this evening for CAZ510-513>515.
PZ...Small Craft Advisory until 9 PM PDT this evening for Pt Pinos to
Pt Piedras Blancas 0-10 nm.
&&
$$
SHORT TERM...Rowe
LONG TERM....Rowe
AVIATION...KB
MARINE...KB
Visit us at www.weather.gov/sanfrancisco
Follow us on Facebook, X, and YouTube at:
www.facebook.com/nwsbayarea
x.com/nwsbayarea
www.youtube.com/nwsbayarea
Prepared by Boulder-Creek.com Weather at: Sat Jun 13 12:30:02 PDT 2026
|
|
From the National Weather
Service |
|
|
|
Copyright © 2002 All rights
reserved Boulder-Creek.com. |
|
Revised:
29 Mar 2008 09:53 -0800 GMT
(Pacific) |
|