Red Flag Warning 2, NWS San Francisco Bay Area, CA

253 
WWUS86 KMTR 280546
RFWMTR

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Francisco CA
1046 PM PDT Thu Aug 27 2026

...RED FLAG WARNING REMAINS IN EFFECT FROM 5 AM TO 3 PM PDT FRIDAY
DUE TO LIGHTNING FOR SANTA CRUZ MOUNTAINS, SOUTHERN SALINAS
VALLEY/ARROYO SECO AND LAKE SAN ANTONIO, SANTA LUCIA MOUNTAINS AND
LOS PADRES NATIONAL FOREST, NORTHERN SALINAS VALLEY/HOLLISTER VALLEY
AND CARMEL VALLEY, NORTHERN MONTEREY BAY, AND SOUTHERN MONTEREY BAY
AND BIG SUR COAST...

....The potential for isolated thunderstorms across the Central Coast
continues to increase from Friday morning through Friday afternoon...

CAZ512-516-517-528>530-281500-
/O.CON.KMTR.FW.W.0002.260828T1200Z-260828T2200Z/
Santa Cruz Mountains-Southern Salinas Valley/Arroyo Seco and Lake
San Antonio-Santa Lucia Mountains and Los Padres National Forest-
Northern Salinas Valley/Hollister Valley and Carmel Valley-
Northern Monterey Bay-Southern Monterey Bay and Big Sur Coast-
1046 PM PDT Thu Aug 27 2026

...RED FLAG WARNING REMAINS IN EFFECT FROM 5 AM TO 3 PM PDT FRIDAY...

* AFFECTED AREA...The Salinas and Carmel Valleys and Hollister Area,
  Monterey Bay and the Big Sur Coast, The Santa Cruz Mountains, and
  Interior Monterey County and the Santa Lucia Range.

* TIMING...From 5 AM to 3 PM PDT Friday.

* THUNDERSTORMS...Lightning strikes with little precipitation and
  gusty and erratic outflow winds of 40 to 50 mph.

* IMPACTS...There will be an increased risk for power outages.
  Lightning strikes may result in new fire ignitions. Erratic outflow
  winds will result in rapid fire spread for both new and existing
  fires.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Please advise responding agencies or fire crews in the field of this
fire weather alert.

Never leave burning debris or camp fires unattended; extinguish them
completely. Avoid using equipment or machinery that could create a
spark. Secure tow chains to avoid dragging and subsequent sparks.
Never toss cigarette butts out of your vehicle's window. Remember,
one less spark, one less flame.

Familiarize yourself with your emergency plan! Where will you go? How
will you get there? Do you have your go kit ready to go? Who will you
call to let others know you are safe? Visit ready.gov/plan for more
information.

&&

$$

JM

336 
WWUS86 KMTR 281351
RFWMTR

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Francisco CA
651 AM PDT Fri Aug 28 2026

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 3 PM PDT THIS AFTERNOON
DUE TO LIGHTNING FOR SANTA CRUZ MOUNTAINS, SOUTHERN SALINAS
VALLEY/ARROYO SECO AND LAKE SAN ANTONIO, SANTA LUCIA MOUNTAINS AND
LOS PADRES NATIONAL FOREST, NORTHERN SALINAS VALLEY/HOLLISTER VALLEY
AND CARMEL VALLEY, NORTHERN MONTEREY BAY, AND SOUTHERN MONTEREY BAY
AND BIG SUR COAST...

....The potential for isolated thunderstorms across the Central Coast
continues from this morning through Friday afternoon...

CAZ512-516-517-528>530-282200-
/O.CON.KMTR.FW.W.0002.000000T0000Z-260828T2200Z/
Santa Cruz Mountains-Southern Salinas Valley/Arroyo Seco and Lake
San Antonio-Santa Lucia Mountains and Los Padres National Forest-
Northern Salinas Valley/Hollister Valley and Carmel Valley-
Northern Monterey Bay-Southern Monterey Bay and Big Sur Coast-
651 AM PDT Fri Aug 28 2026

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 3 PM PDT THIS
AFTERNOON...

* AFFECTED AREA...The Salinas and Carmel Valleys and Hollister Area,
  Monterey Bay and the Big Sur Coast, The Santa Cruz Mountains, and
  Interior Monterey County and the Santa Lucia Range.

* TIMING...Until 3 PM PDT this afternoon.

* THUNDERSTORMS...Lightning strikes with little precipitation and
  gusty and erratic outflow winds of 40 to 50 mph.

* IMPACTS...There will be an increased risk for power outages.
  Lightning strikes may result in new fire ignitions. Erratic outflow
  winds will result in rapid fire spread for both new and existing
  fires.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Please advise responding agencies or fire crews in the field of this
fire weather alert.

Never leave burning debris or camp fires unattended; extinguish them
completely. Avoid using equipment or machinery that could create a
spark. Secure tow chains to avoid dragging and subsequent sparks.
Never toss cigarette butts out of your vehicle's window. Remember,
one less spark, one less flame.

Familiarize yourself with your emergency plan! Where will you go? How
will you get there? Do you have your go kit ready to go? Who will you
call to let others know you are safe? Visit ready.gov/plan for more
information.

&&

$$

RGass

454 
WWUS86 KMTR 282156
RFWMTR

URGENT - FIRE WEATHER MESSAGE
National Weather Service San Francisco CA
256 PM PDT Fri Aug 28 2026

CAZ512-516-517-528>530-282300-
/O.EXP.KMTR.FW.W.0002.000000T0000Z-260828T2200Z/
Santa Cruz Mountains-Southern Salinas Valley/Arroyo Seco and Lake
San Antonio-Santa Lucia Mountains and Los Padres National Forest-
Northern Salinas Valley/Hollister Valley and Carmel Valley-
Northern Monterey Bay-Southern Monterey Bay and Big Sur Coast-
256 PM PDT Fri Aug 28 2026

...RED FLAG WARNING WILL EXPIRE AT 3 PM PDT THIS AFTERNOON...

The threat for thunderstorms has diminished. Therefore the Red Flag
Warning will expire at 3 pm.

$$

Canepa

Area Forecast Discussion
National Weather Service San Francisco CA
726 AM PDT Thu Aug 27 2026

...New UPDATE...

.KEY MESSAGES...
Updated at 1201 AM PDT Thu Aug 27 2026

 - Slight chance of thunderstorms this morning, with shower
   chances through Friday

 - Slight cooling today, with temperatures close to seasonal averages

 - Cooling trend continues Friday into the next week

&&

.UPDATE...
Issued at 725 AM PDT Thu Aug 27 2026

Have updated the forecast to include a slight chance of
thunderstorms through 10 AM this morning for the Central Coast. This
is as we are seeing thunderstorms offshore and moving into Santa
Barbara and San Luis Obispo counties. While there still appears to
be limited instability across the Central Coast, we have added them
due to the convection offshore. We will continue to monitor this
closely throughout the day.

RGass

&&

.SHORT TERM...
Issued at 1201 AM PDT Thu Aug 27 2026
(Today and tonight)

Stratus clouds are developing at the immediate coast and are
expected to generally remain confined to the coastal valleys
overnight before mixing out through Thursday morning. Zooming out
into the Pacific reveals some interesting activity off the coast as
some storm cells with frequent lightning have developed around a
moisture gradient. The latest forecast update includes a slight
chance for thunderstorms for the morning hours, around the time
that these cells would impact the coast if they hold together. As
of the time of writing, they have been dissipating as they move
towards our coastal waters, but the night shift will continue
monitoring these cells as they approach and issue any forecast
updates and products as they become necessary. Beyond the morning
hours, tropical moisture sourced from the remnants of Tropical
Storm Iselle will come into the state, and slight chances for
showers persist through the day. Low, but non-zero, chances for
thunderstorms will tick up again in the afternoon and evening
hours, but the limiting factor appears to be insufficient
atmospheric instability. Will continue to monitor the situation as
it evolves through the day.

The large-scale weather pattern remains dominated by the balance
between the ridging over the Desert Southwest and the troughing over
the eastern Pacific. The ridging has generally won out over the last
few days, but today will mark the very beginnings of a transition to
a more troughing-dominated pattern. Temperatures will remain near to
slightly above the seasonal averages, but we will see a slight
cooldown as highs reach the upper 80s to middle 90s inland, the
upper 90s to the triple digits in the warmest interior locations,
the lower 70s to the lower 80s near the Bays, and the lower to
middle 60s at the Pacific coast. Breezy onshore winds will develop
in the afternoon and evening hours with gusts of 20 to 30 mph at the
coasts.

For a discussion of weather-related impacts to the fire weather
situation, see the FIRE WEATHER section.

&&

.LONG TERM...
Issued at 1201 AM PDT Thu Aug 27 2026
(Friday through Wednesday)

The progression of the trough, and with it the cooling trend and
associated tropical moisture, continue into Friday with the slight
chances for showers continuing through the day. Later on Friday into
the weekend, the tropical moisture dips to the south but the
deepening trough remains, and cooler temperatures continue into the
middle of next week. Temperatures reach their coolest on Monday,
around 5 to 15 degrees below seasonal averages, as high reach the
70s throughout the inland valleys, the 80s along the warmest
interior Central Coast regions, and the upper 50s to the 60s at the
Bays and the Pacific coast. The trough will start to flatten out,
but remains in place with temperatures slow to rise. The forecast
shows rain chances returning to the region for the middle of next
week, but this is critically dependent on how conditions evolve in
the tropical Eastern Pacific, so confidence remains low.

&&

.AVIATION...
(12Z TAFS)
Issued at 428 AM PDT Thu Aug 27 2026

VFR prevails with the exception of KHAF. The marine layer has
remained around 1000ft, unorganized and made little to no inland
push through the overnight hours. VFR is expected to prevail for
most terminals through the forecast period. Confidence is low on
the potential for IFR/LIFR ceilings developing late in the
forecast period along the coastal sites, especially KMRY and KSNS.

Vicinity of SFO...The marine layer has remained at the coastline
overnight. A fetch of offshore flow just above the marine layer
will help maintain VFR conditions now through late tonight into
early Friday morning. Will have to see how well the marine layer
recovers once flow in the lower boundary layer returns to onshore
late in the forecast period.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR with a slight chance of LIFR ceilings
until mid-morning. Offshore flow this far south is more pronounced
and expected to help maintain VFR conditions through the forecast
period. There is a slight chance of showers developing offshore
and moving through the Central Coast and Monterey Bay terminals
through the forecast period. Elevated thunderstorms are not
currently in the forecast, and chances remain low, but cannot be
ruled out entirely.

&&

.MARINE...
(Today through Tuesday)
Issued at 428 AM PDT Thu Aug 27 2026

Fresh to strong northwest winds will persist today and continue
into the weekend with moderate wind driven seas. Near gale force
gusts are possible over the northern outer and coastal waters
this afternoon into tonight. A long period southerly swell will
begin to build above 16 seconds Friday morning, peaking around
17-18 seconds by Saturday morning, and gradually decline Sunday
into Monday.

&&

.FIRE WEATHER...
Issued at 1201 AM PDT Thu Aug 27 2026

One more day of near-critical fire weather conditions above 1000
feet, especially across the Central Coast, as warm and dry
conditions continue above the marine layer inversion and overnight
humidity recoveries remain poor. One thing to note is that even
with the slight chance of rain today into Friday, we are not
expecting wetting rains to develop, while a small but non- zero
chance for thunderstorms raises the specter for a dry lightning-
induced fire start in the higher elevations. Across the Timber and
Plaskett Fires, light offshore winds overnight may lead to
nocturnal drying concerns at the higher elevations. A pattern
change Friday into the weekend will bring cooler temperatures and
likely a deeper marine layer, bringing progressively more relief
to some of the higher elevations.

DialH

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 9 AM PDT Saturday for Pigeon Pt to Pt
     Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt
     Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM-Pt Pinos to Pt
     Piedras Blancas 0-10 nm.

&&

SHORT TERM...DialH
LONG TERM....DialH
AVIATION...JM
MARINE...JM

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