ca discuss
Office: EKA
FXUS66 KEKA 050929
AFDEKA
AREA FORECAST DISCUSSION
National Weather Service Eureka CA
129 AM PST Fri Dec 5 2025
.SYNOPSIS...A deepening marine layer will return along the coast
with patchy drizzle. King tides combined with tidal anomaly will
continue to bring the threat of coastal flooding in low-lying
areas around Humboldt Bay today. A series of frontal systems
moving north of the area will bring a chance of light rain or
sprinkles across the northern portion of the area through the
weekend, especially for Del Norte and Humboldt counties.
&&
.DISCUSSION...High pressure over the Northeastern Pacific has
slightly "flattened" as a series of shortwaves and associated
frontal systems move around the northern periphery of the ridge
towards the Pacific Northwest.
Downstream flow aloft will continue to bring increasing
cloudiness to the area as a weak cold front traverses the Pacific
Northwest. This should aid in a deep marine layer along the North
Coast. Patchy drizzle has already been observed as of 09z this
morning as the deepening marine layer and saturated profile
confirms the previous model data. Overnight temperatures are
forecast to run up to 5 degrees warmer compared with Thursday's
morning. High dew points in the mid 30s to mid 40s will preclude
frost conditions across much of the interior valleys.
With fronts approaching the area from the north, chances increase
for light rain or sprinkles across Del Norte, Humboldt and
Trinity counties this afternoon and well into the evening. Dry
weather conditions are expected to prevail in Mendocino and Lake
counties. Some blustery winds will continue over the coastal
headlands and exposed ridges in Humboldt and Mendocino counties.
Lingering light showers will continue across the northern portion
of the forecast area on Saturday.
On Sunday, another shortwave and frontal system is expected to move
north of our area. The flow aloft will become more zonal, bringing
additional chances of light rain across the northern portion,
especially for Del Norte and northern Humboldt counties.
Elsewhere, partly to mostly cloud skies are expected.
The 500 mb ridge appears to slowly build back early next through mid
next week. WPC ensemble clusters do show about an even split (50%)
of clusters that are "drier" (at least for the North Coast) than the
grand ensemble mean. The ensemble mean is by no stretch very wet
with 0.10-0.25 inches of rain in 24 hours everyday from Monday
through Wednesday, mostly for Del Norte. It could be wet or it could
be dry or both. Stay tuned. -ZVS
&&
.AVIATION...(06Z TAFS)...Ceilings will continue to lower for coastal
terminals into early Friday morning as a weather system passes to
the north of the area. The marine stratus will deepen, with ceilings
in the IFR to high LIFR range. Some drizzle may occur at coastal
terminals early Friday. Interior valleys may also experience low
clouds/fog. It is still unclear if lower ceilings will make it to
KUKI, but there is a definite possibility early Friday. Through the
day Friday ceilings are expected to raise and stratus is anticipated
to push back toward the immediate coast. However, MVFR ceilings may
persist through the day for coastal terminals.
&&
.MARINE...Into Friday morning, northerly winds are expected to move
closer to the Mendocino coast, but remain 15 to 20 kt with the
strongest winds in the lee of Cape Mendocino. The swell remains
fairly low, currently around 2 to 4 feet at 12 seconds and this is
generally expected to continue through Friday.
Friday afternoon and overnight a front approaching the area will
bring a short period of light southerly winds to the northern inner
waters with the outer waters turning westerly. Farther south, winds
will remain northerly around 10 to 18 kt. Over the weekend winds
become southerly north of Cape Mendocino, but only around 5 to 10
kt. Farther south, the northerly winds persist and are around 10 to
15 kt. This pattern is expected to generally continue through
Wednesday with winds remaining fairly light as a series of weather
systems moves by to the north of the area.
Saturday, a larger northwest swell builds into the waters. Currently
it looks to be around 6 to 9 feet at 10 to 12 seconds. This is
expected to diminish to around 5 to 7 feet on Sunday and generally
fluctuate around 5 to 7 feet at 12 seconds into early next week.
-MKK
&&
.COASTAL FLOODING...High astronomical tides are predicted to peak
on today. High tides are forecast to be at 8.80 feet at the North
Spit tide gauge at around 10:55 AM local time. High tides
combined with surge and tidal anomaly will result in water levels
between 9.1 to 9.3 feet MLLW (Mean Low Level Water). Minor coastal
flooding around Humboldt Bay, including King Salmon and Jackson
Ranch Road in the Arcata Bottoms, will be likely between 10AM and
noon. A Coastal Flooding Advisory will be in effect from 10AM to
noon on Friday. High tides are predicted to be at 8.63 feet at
11:44 PM on Saturday. This may cause minor flooding again on
Saturday, with water level remaining nearly half of a foot above
astronomical tides inside Humboldt Bay. -ZVS
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
Coastal Flood Advisory from 10 AM this morning to noon PST
today for CAZ103.
NORTHWEST CALIFORNIA COASTAL WATERS...
Small Craft Advisory until 11 PM PST this evening for
PZZ475.
&&
$$
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
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https://www.facebook.com/NWSEureka
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For forecast zone information
see the forecast zone map online:
https://www.weather.gov/images/eka/zonemap.png
Office: HNX
FXUS66 KHNX 051122
AFDHNX
Area Forecast Discussion
National Weather Service Hanford CA
322 AM PST Fri Dec 5 2025
.UPDATE...
Updated Aviation Section.
&&
.KEY MESSAGES...
1. Fog and low clouds will continue each night and morning
across the San Joaquin Valley for the remainder of this week.
Dense fog will also develop at times in the lower Sierra
foothills, coastal ranges, and the Grapevine.
2. A gradual warming trend will occur in the mountains and
desert until next week, as the high pressure pattern continues
over the region.
&&
.DISCUSSION...
The stratus deck persists over the Central Valley, although
latest satellite imagery shows at least partial clearing towards
the southern San Joaquin valley, such as in Kern County.
Visibility has been 2 miles or better throughout the Central
Valley with ceilings near 1,000 feet this morning. However,
reports of dense fog and reduced visibilities have been received
for locations within the cloud deck, including Interstate 5
through the Grapevine and Pacheco Pass. Webcams in the lower
Sierra Nevada foothills also show dense fog. Any locations where
clouds are clearing will likely become foggy by later tonight;
latest high resolution ensemble guidance shows a 60-70 percent
chance of visibility less than one quarter of a mile over the
San Joaquin Valley.
This pattern will continue for the next several days with
a gradual rise in daytime high temperatures in the mountains
and desert, or a rise to at least a few degrees above average
by the weekend. Additional warming will continue into next week
with highs rising to the lower 70's at the warmest locations in
the desert. Some rise in temperatures is shown for the San
Joaquin Valley next week, but it will depend on the presence of
fog and stratus.
The Climate Prediction Center continues to show high
probabilities (80-90%) of above average temperatures and a
50-60 percent chance of continued below average precipitation
for the next 6-10 days. The 8-14 day outlook shows up to a 40
percent probability of below average precipitation and lower
chances (60% to around 70%) for above average temperatures.
&&
.AVIATION...
LIFR visibilities are expected to continue at KBFL through at
least 18Z Friday, with MVFR/IFR ceilings throughout the rest of
the Valley through at least 19Z-20Z Friday.
&&
.AIR QUALITY ISSUES...
On Friday December 5 2025, Fireplace/Wood Stove Burning Status is:
No Burning Unless Registered in Fresno, Kern, Madera and Merced
Counties. Burning Discouraged in Kings and Tulare Counties, and 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...
Dense Fog Advisory until 10 AM PST this morning for CAZ314.
&&
$$
public...EW
aviation....EW
weather.gov/hanford
Office: LOX
FXUS66 KLOX 051058
AFDLOX
Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
258 AM PST Fri Dec 5 2025
.SYNOPSIS...04/1156 PM.
Light Santa Ana Winds will occur each morning today and Friday.
Freezing conditions will occur across some interior areas this
morning. A significant warming trend will begin this weekend with
temperatures well above normal through next Thursday, peaking next
Tuesday and Wednesday.
&&
.SHORT TERM (TDY-SUN)...05/221 AM.
Three days of benign very nice weather on tap for Srn CA. An upper
high will nose in from the west. Hgts will rise a couple dam each
day and will end up near 584 dam by Sunday. There will be weak
offshore flow through the period, but only in the 2 to 4 mb range.
Skies will be sunny through the period. There will be light, sub
advisory winds each morning.
Low temperatures in wind sheltered locations will be below normal
each morning due to the dry airmass and clear skies which will
allow for very efficient radiational cooling. Freeze warning and
frost advisories are in effect for this morning, but a few degrees
of airmass warming will likely bring low up just enough to
preclude frost/freeze products.
Max temps will cool across the most of the csts and vlys today
and Saturday due to the weaker offshore flow. The Central Coast
will be the exception due to a decent offshore push this morning. The
inland areas will warm each day as the airmass warms. All areas
will warm Sunday as the hgts peak and there is a slight bump up
in the offshore flow. Sunday's max temps will mostly be in the mid
60s to mid 70s across the csts and vlys (mostly 3 to 6 degrees
above normal).
.LONG TERM (MON-THU)...05/255 AM.
The warm up will continue through next week. While all mdls are
warm the EC and its ensembles continue to advertise the most heat.
The east Pac ridge will continue to dominate the Srn CA weather.
There is decent agreement that on Monday and Tuesday the hgts
will be near 586 dam. After that the GFS weakens the high to about
580 dam while the EC keeps it near 586 dam on Wed and then 589 dam
on Thu. For perspective, the average Dec hgt is 571 dam.
At the sfc offshore flow will continue. The offshore flow will be
weak most of the time but will rise to moderate levels on Tuesday
when there will be gustier winds in the morning. But with no upper
level or thermal support its doubtful that there will be advisory
level winds on any of the days.
The ensembles do point to the EC's solution and the max temps have
been adjusted upwards through the period. Even with this boost
there is a 30 percent chc that they are still too low. Right now
the forecast call for 2 to 4 degrees of warming Mon and 1 to 3
degrees on Tuesday. The csts will likely cool a degree or two Wed
as Tuesday's offshore flow relaxes and allows for an earlier
seabreeze. Away from the csts max temps will rise another 1 to 2
degrees each day. Monday's max temps will be 8 to 12 degrees above
normal and by Thursday most max temps will be 12 to 18 degrees
over normal (about 8 degrees at the coasts). Thursday's highs will
be in the lower to mid 80s in the vlys and the 70s across the
csts.
&&
.AVIATION...05/1034Z.
Around 10Z, there was no marine layer depth at KLAX.
High confidence in the current forecast, except moderate
confidence in the current forecast for KPRB. VFR conditions are
expected through the period, except for a 50 percent chance of
VLIFR to LIFR conditions between 12Z and 17Z. There is a low
chance of moderate wind shear through 16Z at Los Angeles County
valley and Ventura County coastal terminals.
KLAX...VFR conditions are expected through at least 10Z Saturday,
then there is a 20 percent chance of LIFR conditions. Any
easterly winds should remain less than 7 knots, but there is a 20
percent chance of easterly winds between 7 and 10 knots through
15Z.
KBUR...VFR conditions are expected through the period. No wind
impacts are expected through the period.
&&
.MARINE...05/234 AM.
Moderate-to-high confidence in the current forecast. Less
confidence in the forecast for the outer waters versus
the nearshore and inner waters.
For the waters southwest through northwest of the Channel Islands
beyond 10 NM offshore of the Central Coast and outside the
southern California bight, there is a high-to-likely (40 to 60
percent) chance of Small SCA level winds developing as late as this
afternoon and lingering through the remainder of the period into
Tuesday. The highest chances of SCA conditions will be for the
northern and western portions (outside the buoy observations)
beyond 30 NM offshore.
Inside the southern California bight and for the nearshore waters
along the Central Coast out to 10 NM offshore, winds and seas
should remain below SCA levels through the period, but there is a
low-to-moderate (20 to 40 percent) chance of SCA level winds
this morning.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement in effect through Saturday morning
for zones 87-349-350-354-362-366. (See LAXCFWLOX).
Freeze Warning remains in effect until 8 AM PST this morning
for zones 343-344-383. (See LAXNPWLOX).
Frost Advisory in effect until 8 AM PST this morning for zone
357. (See LAXNPWLOX).
PZ...Small Craft Advisory in effect from 3 PM this afternoon to 3
AM PST Sunday for zones 670-673. (See LAXMWWLOX).
&&
$$
PUBLIC...Rorke
AVIATION...Hall
MARINE...Hall
SYNOPSIS...Lewis/Ciliberti
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox
Office: STO
FXUS66 KSTO 042134
AFDSTO
Area Forecast Discussion
National Weather Service Sacramento CA
134 PM PST Thu Dec 4 2025
.KEY MESSAGES...
- Periods of clouds, mist, or fog continue in the Central Valley
for the next few mornings
- Seasonable temperatures and light winds are forecast over the
next several days
- Weak system passes to the north this weekend, bringing the
chance for light showers across the Shasta County mountains,
dry weather continues elsewhere for at least the next week
&&
.DISCUSSION...
...Today-Friday...
Current GOES-West visible satellite imagery illustrates the
blanket of stratus in the Central Valley gradually eroding, with
some high clouds passing overhead from the north. Visibilities
have improved across the Central Valley this afternoon, however
you can expect another round of patchy dense fog and low clouds
once again tonight into Friday morning. High resolution guidance
suggests the best potential from Marysville southward. Dry weather
and seasonable temperatures are forecast for the region, with 50s
to 60s in the Valley and foothills, and 40s to 60s in the
mountains for the daytime highs.
...Friday Night-Sunday...
A weak system passing to the north over the weekend may bring
some isolated, light showers to the Shasta County mountains,
however little to no impacts or accumulations are expected.
Elsewhere, dry conditions will persist over the weekend with daily
chances for fog, mist and low clouds especially in the Valley.
High temperatures are forecast to be in the 40s to 60s across
interior NorCal.
...Next Week...
High pressure builds across the region next week, allowing for a
gradual warming trend with high temperatures warming to the 50s
to near 70 (most noticable for areas outside of stratus/fog
development). Dry conditions will continue through next week. Some
ensembles are indicating a pattern change in mid December but
there is a large amount of uncertainty as it is too far out in
time.
&&
.AVIATION...
Lingering low cigs and mist across the Central Valley this
afternoon and evening, although some sites may briefly return to
VFR conditions (mainly across the northern Sacramento Valley).
Another round of BF/FG and low stratus returns tonight after
08-15Z, with areas of MVFR/IFR conditions, locally IFR,
particularly from Sacramento southward. Light and variable surface
winds less than 12kts.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Office: SGX
FXUS66 KSGX 051247 CCA
AFDSGX
Area Forecast Discussion...Corrected
National Weather Service San Diego CA
429 AM PST Fri Dec 5 2025
.SYNOPSIS...
Weak Santa Ana winds will continue across the mountains and
foothills today, followed by weak onshore flow on Saturday. Fog,
potentially dense, could return to the coastal areas Sunday and
Monday mornings. Gradual warming through the middle of next week
and little change through the end of the week with high
temperatures as much as 10-15 degrees above normal and periods of
weak to locally moderate Santa Ana winds.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
Skies are clear this morning with any notable Santa Ana winds
confined to the Cajon Pass, where gusts are currently around 25-35
mph. Weak Santa Ana winds will continue through the morning, then
gradients and winds weaken through the afternoon. An upper level east-
west ridge axis associated with the high over the East Pacific
begins to nudge into So Cal today bringing warming across the
region. Highs will generally be in the upper 60s to low 70s across
the coastal areas, valleys, and low deserts, low 60s in the high
deserts, and 50s in the mountains - around 2 to 4 degrees above
normal.
Pressure gradients become neutral to the east and very weakly
offshore to the north on Saturday, allowing a return of a more
prominent sea breeze in the afternoon. This won't do anything in
terms of moderating temperatures with the upper ridge continuing
to nudge in from the west, but it could lead to the redevelopment
of fog, first over the coastal waters during the afternoon
Saturday, then spreading into the coastal areas Saturday night.
Weak offshore flow develops again by Sunday morning as surface
high pressure develops over the eastern Great Basin and Rockies,
which could help push the fog back out to sea relatively early in
the morning. Winds weaken again Sunday afternoon with another
night of potential fog at the coast before offshore flow returns
again Monday morning. Otherwise warmer on Sunday with highs around
5-10 degrees above normal.
The remainder of next week will be decidedly warm and dry with
periods of weak to locally moderate Santa Ana winds. While there
is high certainty in the overall upper level pattern with the
ridge slowly shifting east, becoming directly overhead around
Thu/Fri, ensembles have a bit of spread in the amplitude of the
ridge. This will affect the track of any short waves to our north
and the subsequent surface high pressure and Santa Ana wind
strength behind them, as well as temperatures. Current forecast
has temperatures peaking at around 10-15 degrees above normal
Tuesday through Friday, reaching the low 80s in the valleys and
low deserts. The CW3E West-WRF ensemble shows Santa Ana winds
peaking Monday and Tuesday when there is around a 65% chance of a
weak-to-moderate event, lowering to around a 40% chance on
Wednesday. This translates to gusts around 30-45 mph in the wind
prone passes, canyons, and foothills, locally around 50 mph in the
favored spots. Ensembles are starting to hint at the East Pac
ridge breaking down and precipitation returning around the middle
of the month, but we'll have to see how well that holds up.
&&
.AVIATION...
051030Z....Mostly clear skies and VFR conditions are expected today
and tonight.
&&
.MARINE...
No hazardous marine conditions are expected through Wednesday.
&&
.BEACHES...
A very high tide this morning will threaten coastal flooding, minor
tidal overflow and beach erosion. Check the Coastal Hazard Message
for details.
&&
.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement until 10 AM PST this morning for Orange
County Coastal Areas-San Diego County Coastal Areas.
PZ...None.
&&
$$
PUBLIC...SS
AVIATION/MARINE/BEACHES...MM
Office: MTR
FXUS66 KMTR 051127
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
327 AM PST Fri Dec 5 2025
...New SHORT TERM, LONG TERM, MARINE...
.KEY MESSAGES...
Updated at 303 AM PST Fri Dec 5 2025
- Hazardous cold conditions through Friday morning for North and
East Bay Valleys and interior Central Coast
- Persistent forecast through the next seven days with benign
conditions and no precipitation expected
- Impacts from Tule Fog continue in the interior East Bay
&&
.SHORT TERM...
Issued at 315 AM PST Fri Dec 5 2025
(Today and tonight)
First and foremost expanded the Cold Weather Advisory to include
the North and East Bay Valleys with the existing advisory over
the Interior Central Coast. A lot less mid-hgih level clouds are
being observed overnight. The clear skies combined with relatively
light winds increased radiational cooling effectiveness
overnight. As such, seeing a lot more observations around that 36
degree threshold. Therefore, went ahead and expanded the Cold
WEather Advisory. Also seeing some radiational fog form over the
North Valleys with patchy dense fog near Santa Rosa. Additionally,
the Central Valley is still seeing some Tule Fog. Just like the
last few nights it will creep into the West Delta and far interior
East Bay Valleys.
Otherwise, the large area of upper level high pressure parked off
the CA will slowly ooze eastward. At the same time a few weak
systems will ride the north periphery of the ridge and move
through the PacNW. These weak system will bring some clouds and
decaying fronts over the NorCal Coast. Previous forecast had a
mentions of showers over the coastal waters today and tonight, but
it's looking less likely. Hi-res guidance is still picking up on
some moisture. In stead of completely removing the precip
converted it to drizzle. Regardless, no impact to land and kept
all chances over the waters.
Sensible weather today will be rather pleasant after the cool
start. Highs today will be mainly in the 60s. For tonight,
expecting less radiational cool due to some increasing clouds and
possible return of low stratus. Will hold off on extending any
Cold Weather Advisories tonight.
&&
.LONG TERM...
Issued at 320 AM PST Fri Dec 5 2025
(Saturday through Thursday)
Pretty benign weather through the long term. The ridge of high
pressure will keep the region high and dry with the exception of
drizzle over the coastal waters this weekend. The ridge of high
pressure is expected to build and strengthen over CA into early
next. As such, additional warming is expected with a general 2 to
4 degrees through the middle of next week. In fact, by next
Wednesday/Thursday interior Central Coast is forecast to reach the
mid 70s with solid 60s to near 70 elsewhere around the Bay Area.
How about rain? Longer range guidance still shows a possible
pattern change by the middle of the month. Cluster analysis of
ensembles show a majority still keeping a ridge, but a few
cluster groups show a breakdown of the ridge. FWIW CPC 8-14 day
outlook is now showing increasing chances for precip Dec 12-18.
&&
.AVIATION...
(06Z TAFS)
Issued at 953 PM PST Thu Dec 4 2025
VFR for most sites but some potential for fog and lowered
visibilities at STS, LVK, and APC. Highest confidence that STS and
LVK will see MVFR to IFR conditions with low to moderate confidence
that APC will see MVFR conditions. A tempo for lowered visibility
may need to be added to APC with guidance showing clouds moving in
and out during the early morning hours. Otherwise, winds remain
light and offshore tonight before a more sustained push of onshore
winds returns by tomorrow afternoon.
Vicinity of SFO...VFR. Winds remain light through tomorrow morning
before moderate onshore winds return during the afternoon/evening
hours.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR. Light, offshore winds continue
overnight with moderate onshore winds returning during the
afternoon/evening. Winds look to weaken and shift offshore again by
tomorrow night.
&&
.MARINE...
(Today through Wednesday)
Issued at 305 AM PST Fri Dec 5 2025
Winds are building across the waters with fresh to strong gusts
expected. These winds persist into the work week. Localized near
gale force gusts are possible across the outer waters through
Saturday. Moderate seas continue with seas building to between 6
to 8 feet Friday through Sunday.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory until 3 PM PST Sunday for CAZ006-506-508-
529-530.
Cold Weather Advisory until 8 AM PST this morning for CAZ506-510-
516-518.
PZ...Small Craft Advisory from 9 AM this morning to 3 AM PST Saturday
for Pt Arena to Pt Reyes 0-10 nm.
Small Craft Advisory from 3 PM this afternoon to 3 AM PST Sunday
for Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 9 PM PST Saturday for Pt Arena to Pt
Reyes 10-60 NM.
Small Craft Advisory until 3 AM PST Sunday for Pigeon Pt to Pt
Pinos 10-60 NM.
&&
$$
SHORT TERM...MM
LONG TERM....MM
AVIATION...Kennedy
MARINE...Murdock
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FXUS66 KMTR 051150
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
350 AM PST Fri Dec 5 2025
...New AVIATION...
.KEY MESSAGES...
Updated at 303 AM PST Fri Dec 5 2025
- Hazardous cold conditions through Friday morning for North and
East Bay Valleys and interior Central Coast
- Persistent forecast through the next seven days with benign
conditions and no precipitation expected
- Impacts from Tule Fog continue in the interior East Bay
&&
.SHORT TERM...
Issued at 315 AM PST Fri Dec 5 2025
(Today and tonight)
First and foremost expanded the Cold Weather Advisory to include
the North and East Bay Valleys with the existing advisory over
the Interior Central Coast. A lot less mid-hgih level clouds are
being observed overnight. The clear skies combined with relatively
light winds increased radiational cooling effectiveness
overnight. As such, seeing a lot more observations around that 36
degree threshold. Therefore, went ahead and expanded the Cold
WEather Advisory. Also seeing some radiational fog form over the
North Valleys with patchy dense fog near Santa Rosa. Additionally,
the Central Valley is still seeing some Tule Fog. Just like the
last few nights it will creep into the West Delta and far interior
East Bay Valleys.
Otherwise, the large area of upper level high pressure parked off
the CA will slowly ooze eastward. At the same time a few weak
systems will ride the north periphery of the ridge and move
through the PacNW. These weak system will bring some clouds and
decaying fronts over the NorCal Coast. Previous forecast had a
mentions of showers over the coastal waters today and tonight, but
it's looking less likely. Hi-res guidance is still picking up on
some moisture. In stead of completely removing the precip
converted it to drizzle. Regardless, no impact to land and kept
all chances over the waters.
Sensible weather today will be rather pleasant after the cool
start. Highs today will be mainly in the 60s. For tonight,
expecting less radiational cool due to some increasing clouds and
possible return of low stratus. Will hold off on extending any
Cold Weather Advisories tonight.
&&
.LONG TERM...
Issued at 320 AM PST Fri Dec 5 2025
(Saturday through Thursday)
Pretty benign weather through the long term. The ridge of high
pressure will keep the region high and dry with the exception of
drizzle over the coastal waters this weekend. The ridge of high
pressure is expected to build and strengthen over CA into early
next. As such, additional warming is expected with a general 2 to
4 degrees through the middle of next week. In fact, by next
Wednesday/Thursday interior Central Coast is forecast to reach the
mid 70s with solid 60s to near 70 elsewhere around the Bay Area.
How about rain? Longer range guidance still shows a possible
pattern change by the middle of the month. Cluster analysis of
ensembles show a majority still keeping a ridge, but a few
cluster groups show a breakdown of the ridge. FWIW CPC 8-14 day
outlook is now showing increasing chances for precip Dec 12-18.
&&
.AVIATION...
(12Z TAFS)
Issued at 349 AM PST Fri Dec 5 2025
Patches of fog and low clouds are affecting portions of the North
Bay and the East Bay. Expect mostly light to moderate winds through
the morning with fog and lower clouds clearing into the mid to late
morning. Winds increase turn northwest into the afternoon for all
but the North Bay and East Bay, which will see southerly and
easterly winds. Expect winds to reduce into the evening and
overnight with fog and low clouds building along the coast and
interior valleys later into the night.
Vicinity of SFO...VFR through the TAF period. Light and variable
winds last into the afternoon. Expect winds to turn northwest and
become moderate in the mid to late afternoon, and reduce into the
late night.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR through the TAF period. Light to
moderate easterly winds last through the afternoon before becoming
northwesterly . Winds weaken and become light into the evening.
Southeast drainage winds look to affect SNS into the late night,
while winds at MRY stay light and variable.
&&
.MARINE...
(Today through Wednesday)
Issued at 305 AM PST Fri Dec 5 2025
Winds are building across the waters with fresh to strong gusts
expected. These winds persist into the work week. Localized near
gale force gusts are possible across the outer waters through
Saturday. Moderate seas continue with seas building to between 6
to 8 feet Friday through Sunday.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory until 3 PM PST Sunday for CAZ006-506-508-
529-530.
Cold Weather Advisory until 8 AM PST this morning for CAZ506-510-
516-518.
PZ...Small Craft Advisory from 9 AM this morning to 3 AM PST Saturday
for Pt Arena to Pt Reyes 0-10 nm.
Small Craft Advisory from 3 PM this afternoon to 3 AM PST Sunday
for Pt Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 9 PM PST Saturday for Pt Arena to Pt
Reyes 10-60 NM.
Small Craft Advisory until 3 AM PST Sunday for Pigeon Pt to Pt
Pinos 10-60 NM.
&&
$$
SHORT TERM...MM
LONG TERM....MM
AVIATION...Murdock
MARINE...Murdock
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