ca discuss
Office: EKA
FXUS66 KEKA 012218
AFDEKA
AREA FORECAST DISCUSSION
National Weather Service Eureka CA
218 PM PST Mon Dec 1 2025
.SYNOPSIS...High risk for sneaker waves Monday through Tuesday.
King Tides return on Tuesday and then peak Thursday and Friday.
Chances for frost and freezing temperatures increase for areas
closer to the coast again starting Tuesday night. Dry weather
expected to prevail for this week, followed by a chance for rain
late Friday and over the weekend.
&&
KEY MESSAGES:
* High risk of sneaker waves is expected along the Northwest
California beaches through Tuesday morning.
* King Tides from December 2nd-7th, and may lead to minor coastal
flooding in low-lying areas around Humboldt Bay, Crescent City and
Arena Cove.
* Dry and seasonably cool weather expected through Friday, followed
by a chance of rain over the weekend.
&&
.DISCUSSION...High pressure is forecast to remain parked over the
northeastern Pacific through Friday. Dry weather is highly probable
for NW California.
Offshore flow (E-NE winds) has been increasing across the interior
ridges overnight, especially in Lake County. Gusts from 25 to 35 mph
verified into Monday morning over the exposed ridges in the eastern
portion of Lake County. These winds are continuing to diminish
throughout the day as the surface pressure gradient relaxes.
Satellite imagery depicts only patchy low clouds near the Mendocino
coastal areas Mendocino this afternoon while sunshine remains
elsewhere.
Another "insider trough" will drive southward across the Great Basin
toward southern California Tuesday through Wednesday. This will
bring increasing high clouds across the area on Tuesday.
Ridging strengthen and upper-level heights rises across the Pacific
Northwest in the wake of the "insider trough". Stronger and blustery
coastal northerly winds are expected in the wake of this trough by
Tuesday afternoon. Gusts around 20-30 mph are forecast. East-
northeast winds will also develop Tuesday night into Wednesday for
the higher terrain and over Lake County, where gusts from 30-40 mph
will be possible over the ridges. Ridge level gusts to 40-45 mph are
on the limbs of the distribution (95th percentile and ensemble max)
over the high mountain peaks.
Chance for frost around Humboldt Bay area Tuesday morning decreases
to around 30% as another shortwave trough generates more cloud cover
tonight. Offshore flow resumes Tuesday night into Wednesday morning
and the chance for frost increases again to around 40-80% for the
Humboldt Bay area. Chance for 32F in the north of Humboldt Bay
increase to about 30-50% Wednesday morning. Meaningful chances for
early morning frost for the North Coast is expected to continue
Thursday morning.
The air mass is not forecast to be exceptionally cold next week.
With dew points in the 20s, calm winds in the valleys and clear
skies overnight, frost and freezing temperatures will once again be
a forecast challenge for inland areas that have not had a freeze
yet. Cold weather advisories for wind chill may also be a factor
with winds around around 5-10 mph and minimum temperatures in the
lower to mid 30s. Fog and low clouds will form each and every night
(100% chance), though the coverage will decrease as the air mass
slowly dries out each day this week.
Massive 500mb ridge appears to flatten out Friday and into next
weekend. All global ensemble prediction systems continue to indicate
increasing chances for 0.10 to 0.25 inches of rain in 24 hours
through the weekend. 24 hour chance for > 1 inch is no more than
20%. It is interesting to note that the majority of WPC ensemble
clusters are drier than the grand ensemble. The ensemble mean is by
no stretch very wet either. It could be wet or it could be dry or
both over multiple days. Stay tuned.
&&
.AVIATION...VFR conditions are expected through the afternoon into
the evening. There is a hint of valley fog forming inland possibly
bringing IFR/LIFR conditions to the Russian River Valley (KUKI).
However, the North coast looks to have enough of an offshore flow to
keep any developing marine stratus trapped in an eddy south of Cape
Mendocino. Light variable winds and the passage of high clouds are
expected for coastal terminals. /DS
&&
.MARINE...Moderate northerly winds have pull away from the coast
this afternoon. Steep seas will largely be confined to the outer
waters for much of the day. Wind waves are combining with a long
period westerly swell which will gradually build to up to 8 ft @ 18
seconds by Tuesday. Combined seas of 8-13 ft are expected. Stronger
northerly winds return tomorrow afternoon, with increasing forecast
confidence in gale force gusts in the outer waters south of Cape
Mendocino and Pt. St. George. Nearshore winds will be lighter, but
peak gusts of 15-25 kts are still possible as are propagating steep
wind waves making conditions hazardous for Small Crafts. North winds
ease slightly and pull offshore by Wednesday. Conditions gradually
improve through the end of the week. JB/DS
&&
.BEACH HAZARDS...A long period swell, up to 22 seconds, will
continue to build in on Monday. This energetic swell is bringing a
high risk for sneaker waves, with surf breakers up to 15ft. The
threat will last through Tuesday. High astronomical tides will
increase the danger, especially over rocks and jetties.
Sneaker waves are a unique hazard, with up to 30 minutes between
waves. Large, unexpected waves can sweep across the beach without
warning, sweeping people into the sea from rocks, jetties, and
beaches. These sneaker waves can also move large objects such as
logs, crushing anyone caught underneath. Even ankle to knee deep
water can knock you down and drag you out when a sneaker wave hits.
Pay attention and stay above the high water line and any wet sand to
stay safe. If the ground is wet, waves have surged there recently.
Stay safe and never turn your back on the ocean! /JJW
&&
.COASTAL FLOODING...King Tides return on Tuesday. High astronomical
tides are predicted from Tuesday through Sunday for Northwest
California. The combination of a high astronomical tides, a positive
tidal anomaly, and a long- period swell will increase the risk of
minor coastal flooding around Humboldt Bay, including King Salmon
and low-lying roads near Arcata Bottoms. /JJW
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
Beach Hazards Statement through Tuesday morning for CAZ101-
103-104-109.
NORTHWEST CALIFORNIA COASTAL WATERS...
Small Craft Advisory from 4 PM Tuesday to 3 AM PST
Wednesday for PZZ450-455.
Small Craft Advisory until 4 PM PST Tuesday for PZZ470-475.
Gale Warning from 4 PM Tuesday to 8 AM PST Wednesday for
PZZ470-475.
&&
$$
NOTE: The full forecast discussion is now regularly issued between
10 am/pm and 1 pm/am. Additional updates will be issued as needed.
Visit us at https://www.weather.gov/eureka
Follow us on Facebook and Twitter at:
https://www.facebook.com/NWSEureka
https://www.twitter.com/NWSEureka
For forecast zone information
see the forecast zone map online:
https://www.weather.gov/images/eka/zonemap.png
Office: HNX
FXUS66 KHNX 020429
AFDHNX
Area Forecast Discussion
National Weather Service Hanford CA
829 PM PST Mon Dec 1 2025
&&
.KEY MESSAGES...
1. Clearing this afternoon will lead to fog development tonight
into tomorrow morning in the San Joaquin Valley.
2. A dry disturbance will introduce increasing winds the deserts
and mountain peaks Wednesday into Thursday.
&&
.DISCUSSION...
Tule Fog may make its return tonight into tomorrow morning due
to the clearing of the stratus this afternoon and the lingering
moisture in the atmosphere near the surface of the Valley. A
Dense Fog Advisory has been issued for the majority of the
Valley from 11 PM tonight through 11 AM tomorrow morning. Take
caution while driving and slow down, especially on the highways
and state routes as vehicles may be difficult to see in the fog.
This fog potential is expected to return by Friday if the
stratus that formed last week makes an appearance again.
A system is then expected to move through the Great Basin
Wednesday into Thursday, which may bring strong winds to the
desert and mountain peaks during that time. This system is not
expected to cause any precipitation, due to the fact that it
will be moving out of western Canada and not offshore where it
would otherwise pick up some marine air. The dry pattern is
expected to continue through the weekend as a ridge builds in
from the Pacific.
&&
.AVIATION...
IFR/LIFR visibilities are expected to form for all TAF sites
from 07Z Tuesday through at least 19Z Tuesday, then conditions
are expected to improve into MVFR/VFR conditions through the
rest of the daylight hours tomorrow.
&&
.AIR QUALITY ISSUES...
ISSUED: 12/01/2025 13:56
EXPIRES: 12/02/2025 23:59
On Tuesday December 2 2025, Fireplace/Wood Stove Burning Status
is: No Burning Unless Registered in Fresno, Kern, Kings,
Madera, Merced, and Tulare Counties. Burning Discouraged in
Kern (Greater Frazier Park Area) and Sequoia National Park and
Forest.
&&
.CERTAINTY...
The level of certainty for days 1 and 2 is medium.
The level of certainty for days 3 through 7 is medium.
Certainty levels include low...medium...and high. Please visit
www.weather.gov/hnx/certainty.html for additional information
and/or to provide feedback.
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
Freeze Warning until 9 AM PST Tuesday for CAZ337>339.
Dense Fog Advisory until 11 AM PST Tuesday for CAZ301>303-
305>307-309>316.
&&
$$
public/aviation...EW
weather.gov/hanford
Office: LOX
FXUS66 KLOX 012301
AFDLOX
Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
301 PM PST Mon Dec 1 2025
.SYNOPSIS...01/156 AM.
Warmer temperatures are expected today as offshore flow returns
with areas of gusty Santa Ana winds. A cooling trend will develop
Tuesday and Wednesday before Santa Ana winds return Thursday with
warmer temperatures into early next week.
&&
.SHORT TERM (TDY-THU)...01/100 PM.
The moderate Santa Ana event was waning early this afternoon with
most places within the Santa Ana Wind corridor likely falling
below wind advisory thresholds by 3 pm, the expiration time of the
Wind Advisory. The break in the wind will be quite short lived as
a second moderate Santa Ana event is likely by around noon
Wednesday and continuing into early Thursday. Slightly stronger
upper level support with this event may bring a bit more
widespread 50 to locally 60 mph gusts across prone mountain and
foothill areas. Elsewhere, gusts of 30 to 50 mph will be common,
potentially extending into the Antelope valley (Wednesday).
Where and when winds drop off the dry air mass will support some
of the coolest overnight lows we have experienced this season
with lows in the 30s and 40s common on colder nights with a
smattering of 20s for the far interior and at high elevations.
Freeze Warnings are in place for tonight for the Antelope Valley
and Interior San Luis Obispo with a Frost Advisory in place for
the Cuyama Valley. If you live in these areas, take steps to
protect any vulnerable animals or plants. Additional Frost/Freeze
products will likely be needed in the next few days, especially
Thursday and Friday mornings, in the wake of the second Santa Ana
Wind event.
Near to below normal temperatures will continue through Thursday.
Mostly sunny skies will prevail, outside of possible push of low
clouds and fog to coastal areas Tuesday night into Wednesday
morning ahead of the second Santa Ana wind event.
.LONG TERM (FRI-MON)...01/100 PM.
Rain free conditions look to continue well into next week. There
is a 50-60 percent chance of a strong ridge building overhead into
early next week with weak to moderate Santa Ana conditions at
times. In this scenario, widespread highs in the mid 70s to mid
80s would be in play for coasts and coastal valleys. If the ridge
is weaker or offshore flow does not materialize (40-50 percent
chance), more seasonably warm temperatures (60s and 70s) would be
common.
&&
.AVIATION...01/1721Z.
At 1642Z at KLAX, there was no marine layer nor an inversion.
Overall, moderate to high confidence in 18Z TAF Package.
VFR conditions are expected at all sites. NE offshore winds are
expected to impact: KOXR, KCMA, KVNY, KPMD, & KWJF. Wind gusts
could be off by 5 kts.
Light LLWS and turbulence is possible over and near mountainous
terrain across Ventura and LA Counties through the period.
KLAX...High confidence in TAF. VFR conditions are expected.
No significant east wind component expected.
KBUR...Moderate to high confidence in TAF. MVFR VSBYs are possible
through 20Z. Otherwise, VFR conditions are expected thru fcst pd.
&&
.MARINE...01/101 PM.
For the Outer Waters, moderate to high confidence in current
forecast. This afternoon through Tuesday afternoon, high
confidence in winds and seas below SCA levels. For Wednesday,
there is a 30% chance of SCA conditions beyond 30 NM from shore.
Winds and seas should remain below SCA levels Friday and Saturday
with a chance of SCA conds on Sunday.
For the Inner Waters north of Point Sal, high confidence in
current forecast. Conditions are expected to remain below SCA
levels through Friday. However, nearshore from Cayucos to Morro
bay offshore wind gusts could approach SCA levels at times.
For the Inner Waters south of Point Conception, moderate to high
confidence in current forecast. For the nearshore waters from
Ventura to west of Santa Monica, SCA level offshore winds are
expected this morning into Tuesday morning. However, there will
likely be a brief lull in winds for a few hours late this
afternoon. There is a 30% chance of another round of offshore
winds for this same area Wednesday night through Thursday morning.
Otherwise, winds and seas are expected to generally remain below
SCA levels through Friday.
&&
.BEACHES...01/101 PM.
A long period west-northwest swell will bring elevated surf
conditions to Southwest California Tuesday through Thursday
morning. High Surf Advisories have been issued across the
Central Coast (8 to 12 feet) and Ventura coastline (7 feet).
Surf heights up to 6 feet can be expected elsewhere. Also,
Very High Tides of 7 to 7.7 (MLLW) are expected across all
beaches.
The combination of the long period swell and high tides could
result in beach erosion with isolated minor coastal flooding,
especially for west- northwest facing beaches from 4 AM to 12 PM
each day.
The Ventura coastline has the greatest overlap of high tides and
surf heights on Wednesday. Therefore, a Coastal Flood Advisory
has been issued from 3AM to 10AM for enhanced impacts. Please
see CFWLOX for more details.
Beach Hazard statements have been issued for Santa Barbara
and LA County Coastline from Tuesday through Saturday morning.
Elevated surf will be highest Tuesday through Thursday.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Frost Advisory in effect from 1 AM to 8 AM PST Tuesday for
zone 38. (See LAXNPWLOX).
High Surf Advisory in effect from 3 AM Tuesday to 3 AM PST
Thursday for zones 340-346. (See LAXCFWLOX).
Freeze Warning in effect from 1 AM to 8 AM PST Tuesday for
zone 344. (See LAXNPWLOX).
Beach Hazards Statement in effect from 3 AM PST Tuesday
through Saturday morning for zones 349-350-362-366. (See LAXCFWLOX).
High Surf Advisory in effect from 3 AM Tuesday to noon PST
Thursday for zone 354. (See LAXCFWLOX).
Coastal Flood Advisory in effect from 3 AM to 10 AM PST
Wednesday for zone 354. (See LAXCFWLOX).
Freeze Warning remains in effect from 1 AM to 8 AM PST
Tuesday for zone 383. (See LAXNPWLOX).
PZ...NONE.
&&
$$
PUBLIC...Munroe
AVIATION...Black
MARINE...Black/Lund
BEACHES...Black
SYNOPSIS...MW
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox
FXUS66 KLOX 012338
AFDLOX
Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
338 PM PST Mon Dec 1 2025
.SYNOPSIS...01/156 AM.
Warmer temperatures are expected today as offshore flow returns
with areas of gusty Santa Ana winds. A cooling trend will develop
Tuesday and Wednesday before Santa Ana winds return Thursday with
warmer temperatures into early next week.
&&
.SHORT TERM (TDY-THU)...01/100 PM.
The moderate Santa Ana event was waning early this afternoon with
most places within the Santa Ana Wind corridor likely falling
below wind advisory thresholds by 3 pm, the expiration time of the
Wind Advisory. The break in the wind will be quite short lived as
a second moderate Santa Ana event is likely by around noon
Wednesday and continuing into early Thursday. Slightly stronger
upper level support with this event may bring a bit more
widespread 50 to locally 60 mph gusts across prone mountain and
foothill areas. Elsewhere, gusts of 30 to 50 mph will be common,
potentially extending into the Antelope valley (Wednesday).
Where and when winds drop off the dry air mass will support some
of the coolest overnight lows we have experienced this season
with lows in the 30s and 40s common on colder nights with a
smattering of 20s for the far interior and at high elevations.
Freeze Warnings are in place for tonight for the Antelope Valley
and Interior San Luis Obispo with a Frost Advisory in place for
the Cuyama Valley. If you live in these areas, take steps to
protect any vulnerable animals or plants. Additional Frost/Freeze
products will likely be needed in the next few days, especially
Thursday and Friday mornings, in the wake of the second Santa Ana
Wind event.
Near to below normal temperatures will continue through Thursday.
Mostly sunny skies will prevail, outside of possible push of low
clouds and fog to coastal areas Tuesday night into Wednesday
morning ahead of the second Santa Ana wind event.
.LONG TERM (FRI-MON)...01/100 PM.
Rain free conditions look to continue well into next week. There
is a 50-60 percent chance of a strong ridge building overhead into
early next week with weak to moderate Santa Ana conditions at
times. In this scenario, widespread highs in the mid 70s to mid
80s would be in play for coasts and coastal valleys. If the ridge
is weaker or offshore flow does not materialize (40-50 percent
chance), more seasonably warm temperatures (60s and 70s) would be
common.
&&
.AVIATION...01/2332Z.
At 2330Z at KLAX, there was no marine layer nor an inversion.
Overall, moderate to high confidence in 00Z TAF Package. VFR
conditions are expected at all sites. NE offshore winds will
continue to weaken tonight.
Light LLWS and turbulence is possible over and near mountainous
terrain across Ventura and LA Counties through this evening.
KLAX...High confidence in TAF. VFR conditions are expected.
No significant east wind component expected.
KBUR...High confidence in TAF. VFR conditions are expected.
&&
.MARINE...01/101 PM.
For the Outer Waters, moderate to high confidence in current
forecast. This afternoon through Tuesday afternoon, high
confidence in winds and seas below SCA levels. For Wednesday,
there is a 30% chance of SCA conditions beyond 30 NM from shore.
Winds and seas should remain below SCA levels Friday and Saturday
with a chance of SCA conds on Sunday.
For the Inner Waters north of Point Sal, high confidence in
current forecast. Conditions are expected to remain below SCA
levels through Friday. However, nearshore from Cayucos to Morro
bay offshore wind gusts could approach SCA levels at times.
For the Inner Waters south of Point Conception, moderate to high
confidence in current forecast. For the nearshore waters from
Ventura to west of Santa Monica, SCA level offshore winds are
expected this morning into Tuesday morning. However, there will
likely be a brief lull in winds for a few hours late this
afternoon. There is a 30% chance of another round of offshore
winds for this same area Wednesday night through Thursday morning.
Otherwise, winds and seas are expected to generally remain below
SCA levels through Friday.
&&
.BEACHES...01/101 PM.
A long period west-northwest swell will bring elevated surf
conditions to Southwest California Tuesday through Thursday
morning. High Surf Advisories have been issued across the
Central Coast (8 to 12 feet) and Ventura coastline (7 feet).
Surf heights up to 6 feet can be expected elsewhere. Also,
Very High Tides of 7 to 7.7 (MLLW) are expected across all
beaches.
The combination of the long period swell and high tides could
result in beach erosion with isolated minor coastal flooding,
especially for west- northwest facing beaches from 4 AM to 12 PM
each day.
The Ventura coastline has the greatest overlap of high tides and
surf heights on Wednesday. Therefore, a Coastal Flood Advisory
has been issued from 3AM to 10AM for enhanced impacts. Please
see CFWLOX for more details.
Beach Hazard statements have been issued for Santa Barbara
and LA County Coastline from Tuesday through Saturday morning.
Elevated surf will be highest Tuesday through Thursday.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Frost Advisory in effect from 1 AM to 8 AM PST Tuesday for
zone 38. (See LAXNPWLOX).
High Surf Advisory in effect from 3 AM Tuesday to 3 AM PST
Thursday for zones 340-346. (See LAXCFWLOX).
Freeze Warning in effect from 1 AM to 8 AM PST Tuesday for
zone 344. (See LAXNPWLOX).
Beach Hazards Statement in effect from 3 AM PST Tuesday
through Saturday morning for zones 349-350-362-366. (See LAXCFWLOX).
High Surf Advisory in effect from 3 AM Tuesday to noon PST
Thursday for zone 354. (See LAXCFWLOX).
Coastal Flood Advisory in effect from 3 AM to 10 AM PST
Wednesday for zone 354. (See LAXCFWLOX).
Freeze Warning remains in effect from 1 AM to 8 AM PST
Tuesday for zone 383. (See LAXNPWLOX).
PZ...NONE.
&&
$$
PUBLIC...Munroe
AVIATION...Gomberg
MARINE...Black/Lund
BEACHES...Black
SYNOPSIS...MW
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox
Office: STO
FXUS66 KSTO 011941
AFDSTO
Area Forecast Discussion
National Weather Service Sacramento CA
1141 AM PST Mon Dec 1 2025
.KEY MESSAGES...
- Periods of clouds, mist, or fog continue in the Central Valley
for the next few mornings.
- Breezy north to east winds Wednesday into Thursday, strongest
in the Valley and Delta.
- Weak system brushes by the area this weekend, bringing the
chance for showers, mainly across Shasta County. Dry weather
continues elsewhere for the foreseeable future.
&&
.DISCUSSION...
...Tonight - Tuesday...
Morning fog and stratus have begin to break up early this
afternoon (finally!), more so than we've seen the past few days.
Latest hi-res guidance attempts to clear out the entire Sac and
northern San Joaquin valleys by this evening before sunset. The
set-up for tonight will be a battle between how much we clear out
over the next several hours and an incoming cloud shield from
inside-slider system over the the Great Basin that will drop south
across the area tonight. There may be enough clearing across the
southern Sac Valley and northern San Joaquin before the clouds
arrive to allow for the development of fog again by Tuesday
morning. Certainly will be something to watch in the near-term.
...Wednesday - Friday...
Aforementioned inside-slider will skirt southeast of the state on
Wednesday and into the Four Corners region by Wednesday night
into Thursday. Tightened gradient will allow for breezy north to
northeast winds across the area during the period. Winds will be
strongest in the typical spots with a northerly pattern: across
the western side of the Sac Valley and into the Delta (gusts 20-35
mph), and over the Sierra crest (up to 45 mph). Not expecting too
much in the way of impacts with the wind but it should be enough
to scour out persistent Valley stratus and fog. Ridging then
rebuilds over the area for the end of the work week with near-
normal temperatures.
...Saturday - Sunday...
A weak shortwave will move across the Pacific Northwest this
weekend leading to more zonal flow across the area. Also brings
about the potential for light showers, mainly across Shasta County
and northern Sierra but ensembles aren't too excited about much in
the way of accumulation or any impacts. Elsewhere dry weather will
continue. The next hint at a potential pattern change comes by the
following weekend but we'll see how that develops over the next
week or so.
&&
.AVIATION...
Gradually improving ceilings across the Central Valley this
afternoon and evening, should improve back to VFR. Depending on
degree of clearing, will likely see another round of BF/FG and low
stratus for most sites returning tonight after 08-12Z. Potential
for period of IFR/LIFR cigs, especially from Sacramento southward.
Generally light and variable surface winds less than 10 kts for
TAF sites thru Tuesday afternoon.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Office: SGX
FXUS66 KSGX 012143
AFDSGX
Area Forecast Discussion
National Weather Service San Diego CA
143 PM PST Mon Dec 1 2025
.SYNOPSIS...
Weak to locally moderate Santa Ana winds continuing today, waning
this evening with onshore flow returning Tuesday afternoon.
Chances increase for another round of weak to moderate Santa Ana
winds late Wednesday into Friday, peaking late Wednesday into Thursday.
Gradual warming Thursday into next weekend with highs near
seasonal normals.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
On the heels of the inside sliding upper trough now ejecting into
the Great Plains, a 1032 mb surface high pressure has pushed through
the Great Basin, establishing our offshore pressure gradient with
weak to moderate Santa Ana winds already in place. The strongest
winds remain primarily through mountain and just below passes where
wind gusts of 30-50 mph have been observed with 20-30 mph gusts
stretching into inland valleys. The offshore pressure gradient
quickly relaxes later today with offshore gusts ceasing by midnight.
Onshore flow resumes by Tuesday afternoon. Temperatures today should
reach the mid 70s for most locations beyond 10 miles inland due to
the offshore winds. The marine layer has also been completely pushed
out today, but could low marine clouds/fog sneak into portions of
southern coastal San Diego County Tuesday morning. With onshore flow
resuming tomorrow and ahead of the next trough coming Tuesday night,
the marine layer deepens, likely stretching well into inland valleys
come Wednesday morning. High temperatures cool a few degrees for
Tuesday afternoon as well.
The trend away from light precipitation in favor of a dry offshore
wind event is now complete, with less than a 5% chance of
precipitation. If anything, the deeper marine layer will be what
ends up providing any moisture to the coasts/valleys Wednesday
morning. With fairly high confidence in another inside slider
Tuesday into Wednesday, offshore Santa Ana winds are expected to
pick up again Wednesday, likely persisting through Friday. The track
of this trough follows a very similar track to the one earlier in
the week and wind strength will be similar to today's event as a
result. Winds peak late Wednesday into Thursday with gusts of 30-50
mph in mountain passes and 20-30 mph within downstream corridors of
inland valleys. Weak offshore flow continues into Friday morning
with the return of onshore flow by Friday afternoon. Temperatures
continue to gradually warm Wednesday through the weekend with the
persistent offshore flow giving way to weak upper ridging building
this weekend.
&&
.AVIATION...
012100Z....Coasts/Valleys...Offshore northeast winds 20-30kts with
locally higher gusts will continue in the foothills and inland
valleys through 02z Tue. Very patchy low clouds based around 1200-
1500 feet MSL will develop offshore after 06z, pushing into coastal
areas on Tuesday. There is a 30% of a brief CIG at KSAN and 20%
chance at KSNA, mostly after 11z. Otherwise, mostly clear and VFR
conditions will prevail tonight and tomorrow.
.Mountains/Deserts...VFR conditions through the period. Gusty
northeast surface winds on the coastal slopes of the mountains today
exceeding 35kts at times. Mod up/down drafts possible in the
vicinity of the mountain peaks. Localized areas of BLDU possible.
Winds diminish after 06z Tue.
&&
.MARINE...
No hazardous marine conditions are expected today through Friday.
&&
.BEACHES...
Astronomical high tides are forecast during the mornings Wednesday
through Friday, threatening minor tidal overflow and beach erosion.
Chances of these impacts are higher Wednesday and Thursday mornings
as elevated surf of 4-6 feet and a period of 16 seconds combines
with the high tides, especially for San Diego County.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement from Tuesday evening through Friday
morning for Orange County Coastal Areas-San Diego County
Coastal Areas.
PZ...None.
&&
$$
PUBLIC...Munyan
AVIATION/MARINE/BEACHES...Zuber
Office: MTR
FXUS66 KMTR 020456
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
856 PM PST Mon Dec 1 2025
...New UPDATE, MARINE...
.KEY MESSAGES...
Updated at 145 PM PST Mon Dec 1 2025
- Less fog and stratus today, even less tomorrow.
- Inside slider promotes gusty offshore flow Wednesday morning
across North Bay, Bay Area, and Santa Cruz Mtns. Gusts to 45
mph possible in higher terrain. Limited fire weather concern
thanks to high fuel moisture.
- Quiet and dry after midweek into the weekend. Still looking
like the next chance for a meaningful pattern change is around
the middle of the month.
&&
.UPDATE...
Issued at 849 PM PST Mon Dec 1 2025
Satellite imagery shows mostly clear skies across the region with
lingering spillover from the Tule fog present in the far interior
reaches of southeastern Santa Clara and eastern San Benito
Counties. The North Bay is seeing wisps of high-level clouds, the
forerunners of a stream of clouds moving southwards over southern
Oregon and northern California. This feature will disrupt the
radiational cooling expected tonight, the question is how much,
and will it be enough to keep the Tule fog, in addition to patches
of fog in the Bay Area valleys from forming tonight? The latest
runs of the high resolution models suggest that it won't be enough
with the fog returning to the interior Bay Area valleys through
the night. Nevertheless, the night shift will monitor the
developing situation overnight and assess the need for a Dense Fog
Advisory as needed. No other changes to the forecast at this time.
DialH
&&
.SHORT TERM...
Issued at 145 PM PST Mon Dec 1 2025
(This evening through Tuesday)
Less cloudiness for most places today thanks to a weak upper level
disturbance and a light push of offshore winds overnight. This
helped dry the low-to-mid levels and provide enough mixing aloft
to aid in a quicker clearing to clear skies today. Some areas
still holding on to fog and low clouds in far eastern Contra Costa
and Alameda counties bordering the central valley. We can expect
this trend to continue into Tuesday with dryer and in place,
resulting in temps a couple of degrees warmer than today.
&&
.LONG TERM...
Issued at 145 PM PST Mon Dec 1 2025
(Tuesday night through next Sunday)
By Tuesday night we'll start to see a deep upper low digging into
the Great Basin in what appears as an inside slider. Surface high
pressure building in northern NV in the wake of this system
promotes a strong offshore oriented pressure gradient that will
result in gusty offshore winds. Winds set to increase going into
Tuesday night, increasing through early Wednesday morning and
peaking sometime by noon Wednesday. We're anticipating NE winds
25-35 mph with potential gusts to 40 mph across the North Bay,
East Bay Hill, and Santa Cruz Mtns. Some potential for isolated
gusts to 50 mph along the higher ridgetops of the interior North
Bay. Things will certainly dry out with this burst of offshore
flow, but we aren't expecting RH to get below the 30-40% range for
most. Isolated areas at highest elevations in the interior North
Bay may see RH as low as 25-30% Wednesday. Despite the gusty and
dry conditions, fuel moisture should mitigate most fire weather
concerns thanks to productive rainfall in early November. Beyond
the middle of the week, things look much quieter and a return to a
benign pattern with the ridiculously resilient ridge (RRR)
dominating through the weekend.
&&
.AVIATION...
(00Z TAFS)
Issued at 333 PM PST Mon Dec 1 2025
IFR-MVFR stratus lingers in the interior East bay, especially east
of the Diablo Range, through the next few hours fueled by dense
stratus across the Central Valley. VFR conditions with thin high
clouds, almost like an elevated haze, prevail everywhere else with a
generally gentle offshore flow across the region. Winds will
diminish overnight, and radiational fog and stratus development is
possible in the inland valleys and the interior East Bay. The nature
of radiational fog development makes it very hard, almost
impossible, to forecast the exact extent, but the highest
probability of impact seems to be across the North and East Bay
valleys, with some possibilities of development near SFO as well.
Stratus will dissipate through Tuesday morning with a gentle onshore
flow developing Tuesday afternoon.
Vicinity of SFO... Low confidence of MVFR-IFR stratus developing
Tuesday morning, covered by a TEMPO group in the current TAF. Gentle
southeast flow will continue through the evening hours, with light
winds overnight before onshore flow resumes Tuesday afternoon.
SFO Bridge Approach... Similar to SFO.
Monterey Bay Terminals... VFR through the TAF period. Winds remain
relatively light throughout, with generally onshore flow during the
day before turning to a drainage flow overnight.
&&
.MARINE...
(Tonight through next Sunday)
Issued at 849 PM PST Mon Dec 1 2025
Hazardous marine conditions return Tuesday afternoon as northerly
breezes increase to become fresh to strong and seas become rough
to very rough. Gale force gusts are expected over the northern
outer waters. Conditions improve Thursday with moderate northerly
breezes and moderate seas. Locally strong winds and rough seas
will remain possible over the far northwestern portion of the
northern outer waters.
&&
.BEACHES...
Issued at 1014 AM PST Mon Dec 1 2025
Hazardous beach conditions will continue into Wednesday evening with
a very energetic surf zone. A beach hazards statement remains in
effect for the coastline from Sonoma County to Monterey County
through 10 PM PST Wednesday evening. Breaking waves 10 to 14 feet,
with long lulls of 10 to 20 minutes or more between largest sets can
be expected. Some of the favored break points may exceed 20 feet at
times. Forerunners will be 18+ seconds with heights of 2-5 feet into
tonight resulting in the greatest risk for sneaker waves. This
combined with high astronomical tides in the morning hours will
increase the aforementioned risk. Sneaker waves can unexpectedly run
significantly farther up the beach than normal, including over rocks
and jetties. Rip currents are typically more frequent and stronger
in the vicinity of jetties, inlets, and piers.
RGass
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through Wednesday evening for CAZ006-505-
509-529-530.
Coastal Flood Advisory from 6 AM Tuesday to 3 PM PST Sunday for
CAZ006-506-508-529-530.
PZ...Small Craft Advisory from 3 PM Tuesday to 3 AM PST Wednesday for
Pt Arena to Pt Reyes 0-10 nm.
Small Craft Advisory from 9 AM to 3 PM PST Tuesday for Pt Arena
to Pt Reyes 10-60 NM.
Gale Warning from 3 PM Tuesday to 3 AM PST Wednesday for Pt
Arena to Pt Reyes 10-60 NM.
Small Craft Advisory from 9 PM Tuesday to 3 AM PST Wednesday for
Pigeon Pt to Pt Pinos 10-60 NM.
&&
$$
SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...DialH
MARINE...Sarment
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