ca discuss
Office: EKA
FXUS66 KEKA 272104
AFDEKA
AREA FORECAST DISCUSSION
National Weather Service Eureka CA
104 PM PST Thu Nov 27 2025
.SYNOPSIS...A weakening front may generate light showers tonight
through Friday morning, primarily for Del Norte and northern
Humboldt. Otherwise, dry and seasonably cool weather is forecast
for the next 7 days. A highly energetic long period west swell
will bring an increased risk for hazardous beach conditions Monday
through Tuesday next week.
&&
.DISCUSSION...Decaying frontal boundary trailing southwestward
from a surface low offshore the Pacific NW has been slowly
moving toward the North Coast this afternoon. So far only 0.01 to
0.04 inches of rain has occurred, mostly in Del Norte. High
resolution models continue to depict a shallow moist layer pushing
onshore this evening and overnight for perhaps additional light
rain on the order of a few hundredths in the Humboldt Bay area.
High resolution ensemble guidance indicates highest chances for
0.10 to 0.20 inches in 24 hours ending 4 AM Fri over Del Norte
County and coastal areas of northern Humboldt north of Trinidad.
Above normal 500mb heights will most likely (80% chance) keep much
of Northwest California in a long stretch of dry weather all next
week.
There are a couple of caveats for light spotty precip, however.
A trailing trough and surface low south of 40N will approach 130W
on Fri, and then drift southward through the day. All models keep
this low too far offshore for precip concerns. Another shortwave
trough will swoop down across the Pacific NW into the Great Basin
over the weekend. This trough has an overland trajectory and will
most likely serve to reinforce the dry offshore flow across our
forecast area. Overnight frost and freezing morning temperatures
will once again be prime concern for those with sensitive plants.
A third shortwave trough may (10% chance) generate fleeting
showers for Del Norte and mountains of Trinity Mon or Tue. This
second insider slider trough will carve out a larger scale trough
that will promote blustery N and NE winds around mid week. With
lower dew points, calm winds in the valleys, clear skies and long
nights, the threat for frost or freezing temperatures will once
again crop up. A killing freeze has already occurred multiple
times in Trinity, northern interior Mendocino and northern Lake
Counties. We have suspended issuing frost and freeze products for
these areas until spring. Cold weather products for wind chill may
be necessary if an unseasonably cold air mass settles over the
area around mid next week. There are subtle signs of omega block
break down or a westward shift in the longwave the following
weekend of Dec 6-7 and consequential precip will be possible.
&&
.AVIATION...(18Z TAFS)...General overcast skies will continue to
move through the region as a dry weak front progresses east. Chances
for light rain will diminish greatly by late this evening for
coastal terminals in northern Humboldt and Del Norte counties. MVFR
ceilings will continue for coastal terminals through this TAF period
with ceilings approaching IFR conditions overnight and into early
Friday morning. General cloudiness will continue into late Friday
morning. /JLW
&&
.MARINE...Winds are shifting northerly this afternoon in the wake of
the passing front. Northerlies will increase into Friday, especially
in the southern waters. Models support that the strongest winds will
be south of Cape Mendocino, with potential gusts up to 20 kts. For
the weekend, northerly winds are anticipated to expand northward
with gusts to 25 kts across the outer waters by Sunday.
A forerunner mid-period WNW swell around 8 to 12 feet at 11 to 12
seconds will continue to build in this afternoon/evening. Wind waves
around 6 to 9 feet at 8 seconds expected on Sunday.
&&
.BEACH HAZARDS...A highly energetic long period westerly swell
group generated from a Hurricane Force low pressure system near
the international dateline (180th meridian) will arrive Sunday
night and build through the day on Monday. This high energy swell
will bring a high risk for sneaker waves to Northwest California
beaches on Monday. The sneaker wave risk will probably persist
Monday night and Tuesday, though should decay to moderate levels
as swell heights increase to 10 feet or more. 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! /ZVS
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
Small Craft Advisory from 3 PM this afternoon to 9 AM PST
Friday for PZZ450-470.
Small Craft Advisory from 11 PM this evening to 9 AM PST
Friday for PZZ455-475.
&&
$$
NOTE: The full forecast discussion is now regularly issued between
10 am/pm and 1 pm/am. Additional updates will be issued as needed.
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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 270841
AFDHNX
Area Forecast Discussion
National Weather Service Hanford CA
1241 AM PST Thu Nov 27 2025
&&
.KEY MESSAGES...
1. Dense Fog Advisory issued for the San Joaquin Valley valid
through 1 PM Thursday due to persistent chances for fog each
night and morning through that timeframe.
2. Temperatures near to just below season averages through the
week.
3. Indications for back-to-back dry low pressure systems sliding
in over the weekend to end the month and Tuesday into Wednesday
to begin December.
&&
.DISCUSSION...
Stratus lingered around again yesterday which helped keep
things cool. This was due to the ridge of high pressure over the
West Coast. The stratus is anticipated to break today due to
warmer temperatures with the higher cloud deck and the change
over the weekend. Yet, we have a 70 to 95 percent chance of
highs of at least 60 degrees for most of the Valley in the NBM.
However, latest model ensembles have changed as a shortwave
trough that has been monitored the past few days remains weak in
the latest runs and goes over the Rockies instead. However, two
new troughs are of note. The first one is a faster moving
trough to the west of the ridge which will cutoff early Friday
before shifting well south and parks itself between Hawaii and
Baja California. At the same time, a new shortwave slides in
from Alaska on Saturday as an inside slider through Sunday into
Monday. However, the models continue to back off with any
precipitation as there is now a less than 10 percent chance of
any rain in the Valley and even a 20 percent or less chance of
any snow accumulation.
The ensembles have another shortwave trough sliding down Tuesday
into Wednesday. Both have it being an inside slider but the
precip chances are still low with this one as it will have a
drier flow from Alaska and interior Canada than from the Gulf of
Alaska or the Central Pacific.
&&
.AVIATION...
IFR to MVFR ceilings and visibilities will persist in most
Valley locations through 18Z Thursday. After 18Z, conditions
will improve especially after 20Z. However, MVFR to IFR
conditions return around 06Z Friday for the overnight hours.
&&
.AIR QUALITY ISSUES...
ISSUED: 11/26/2025 13:52
EXPIRES: 11/27/2025 23:59
On Thursday November 27 2025, Fireplace/Wood Stove Burning
Status is: No Burning Unless Registered in Fresno, Kern, Kings,
Madera, and Tulare Counties. Burning Discouraged in Merced
County, and Kern (Greater Frazier Park Area) and Sequoia
National Park and Forest.
&&
.CERTAINTY...
The level of certainty for days 1 and 2 is high.
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 1 PM PST this afternoon for
CAZ301>303-305>307-309>312-314-315.
&&
$$
JPK
weather.gov/hanford
Office: LOX
FXUS66 KLOX 280430
AFDLOX
Area Forecast Discussion
National Weather Service Los Angeles/Oxnard CA
830 PM PST Thu Nov 27 2025
.SYNOPSIS...27/625 PM.
Dry weather will continue at least through the middle of next
week. A cooling trend will begin Friday and continue into next
week as an upper low approaches the area.
&&
.SHORT TERM (THU-SUN)...27/643 PM.
***UPDATE***
After a couple of warm days west of the mountains thanks to Santa
Ana winds, temperatures will cool significantly across the coast
and valleys as gradients trend from offshore to weakly onshore.
Highs should decrease by 5 to 10 degrees on average for these
areas on Friday. At the same time, across the mountains and
interior sections, including the Antelope Valley, highs will warm
by around the same amount. Further cooling is expected on Sunday,
then a slight rebound on Monday with a return of weak offshore
flow.
Meanwhile, under the onshore flow regime, low clouds are expected
to return to coastal areas Saturday and Sunday.
***From Previous Discussion***
Offshore flow peaked Wednesday and while temperatures are warming
up today and some areas, especially in the valleys, will be just
as worm as yesterday, coastal areas should feel an earlier sea
breeze this afternoon.
A rapid return to onshore flow will take place over the next
couple days, leading to much cooler temperatures, back to within a
few degrees of normal by Saturday. Could see a return of the
marine layer to the beaches by then as well.
On Sunday a weak upper trough will pass through the Great Basin.
At one time this system had a chance to bring some rain to the
area but the upper level pattern has shifted this system too far
to the east. Instead, there will be an increase in winds across
the mountains but at this point winds should remain below advisory
levels. Otherwise, just a slight cooling trend but otherwise
pleasant weather and temperatures near to slightly below normal.
.LONG TERM (MON-THU)...27/1156 AM.
On Monday the ensembles are leaning towards the development of
another offshore flow pattern following the passage of the
previous trough. The deterministic models are not quite on board
with this yet, but the ensembles are showing between a 4-6mb
offshore gradient to the east Monday and the GEFS does indicate
some light offshore flow aloft. This has a very similar look and
feel to the current offshore pattern with a strong gradient but
lacking in upper support. The main difference is that there is a
little more cold advection early next week so temperatures are not
expected to be as warm, though there should be at least a minor
warm up Monday from the downsloping winds off the Transverse
Range.
Offshore flow is expected to quickly return to onshore Tuesday
leading to a cooling trend that is expected to continue into
Wednesday as yet another inside slider trough comes through. There
are a few ensemble members indicating some light rain with this on
Wednesday and/or Thursday, mainly south of Point Conception, but
the more likely outcome is the trough staying farther east with
dry conditions locally with seasonably cool conditions.
&&
.AVIATION...28/0002Z.
At 2303Z at KLAX, the marine layer was 800 ft deep, with an
inversion up to 1500 ft and a maximum temperature of 23 C.
Moderate to high confidence in TAF package. At KPRB and KSMO
there is a 20% chance of VLIFR/LIFR conditions from 13Z to 17Z,
and a 10% chance at KOXR and KSBA.
There is 30% chance that no cigs develop KLGB and KLAX.
KLAX...Moderate confidence in TAF, there is a 30% chance of VFR
conditions through the period. Good confidence in any east wind
component remaining below 7-8 knots through forecast period.
KBUR...High confidence in VFR TAF.
&&
.MARINE...27/829 PM.
A coastal jet is expected to develop overnight into Friday with
Small Craft Advisory level winds and borderline seas across the
northern Outer Waters (PZZ670). These conditions could spread
into PZZ673 at times especially Friday afternoon and evening.
Hazardous conditions for small craft should last through early
Saturday morning. Then, conditions will struggle to meet SCA
criteria even beyond 30NM from shore through Sunday morning.
Chances do increase Sunday afternoon and evening, but still
looks unimpressive and borderline. For all Inner Waters, conds
are expected to remain below SCA levels through the weekend.
Low to moderate chances for borderline SCA conditions across the
Outer Waters beyond 30NM from shore and low to very low chances
elsewhere across coastal waters Monday through Wednesday.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect from 3 AM Friday to 3 AM PST
Saturday for zone 670. (See LAXMWWLOX).
&&
$$
PUBLIC...MW/CC
AVIATION...Black
MARINE...Black/CC
SYNOPSIS...MW/CC
weather.gov/losangeles
Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox
Office: STO
FXUS66 KSTO 272129
AFDSTO
Area Forecast Discussion
National Weather Service Sacramento CA
129 PM PST Thu Nov 27 2025
.KEY MESSAGES...
- Dry conditions and periods of morning Valley and adjacent
foothills fog continue late week into the weekend
- Seasonable temperatures and dry weather favored for
Thanksgiving Day
- Decreasing chances for precipitation but periodically breezy
north to east winds expected late weekend into next week
&&
.DISCUSSION...
...Today - Friday...
Current GOES-West imagery shows a broad stratus deck enveloping
the Delta, Valley, and adjacent lower foothills this afternoon.
Any lingering patchy fog and reduced visibilities will continue to
improve through the remainder of the day, with additional dense
fog development anticipated this evening into Friday morning.
Probabilities of visibilities less than a half-mile currently sit
around 50 to 70 percent throughout the Delta, Valley, and adjacent
foothills locations. Aside from periodic fog development, cool
and dry weather are expected to persist through the end of the
week as well.
...This Weekend - Next Week...
While a slight chance for isolated mountain showers remains
possible late Saturday into Sunday, predominantly dry weather is
expected to continue this weekend into early next week. Breezy
north to east winds will be possible Sunday into Monday as well,
although strongest wind gusts up to 35 mph are expected along the
Sierra at this time. With a more persistent offshore wind pattern
setting up late weekend into next week, fog development is
expected to be lesser relative to this past week. Otherwise,
seasonable temperatures look to persist. Ensemble guidance then
indicates some potential for a trough retrograding toward the west
coast around the middle of the week. While uncertainty remains
high at this time, potential for breezier north to east winds and
another slight chance for mountain showers will be possible.
&&
.AVIATION...
Areas of MVFR to IFR conditions linger across the Central Valley
until around 23z Thursday, then MVFR to VFR conditions expected
until near 06z Friday before IFR to LIFR conditions return to the
Delta, Sacramento Valley, and northern San Joaquin Valleys into
18z Friday. MVFR and IFR conditions then until 23z Friday. Light
and variable winds generally less than 12 kts across interior
NorCal for the next 24 hours.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory from 10 PM this evening to 11 AM PST Friday
for Carquinez Strait and Delta-Central Sacramento Valley-
Northern Sacramento Valley-Northern San Joaquin Valley-Southern
Sacramento Valley.
&&
$$
Office: SGX
FXUS66 KSGX 280440
AFDSGX
Area Forecast Discussion
National Weather Service San Diego CA
840 PM PST Thu Nov 27 2025
.SYNOPSIS...
A cooling trend will develop from Friday into the weekend, most
notably for the mountains and western valleys, as high pressure
weakens over the region. Low clouds and fog will also return to
the coastal areas and inland valleys as onshore flow replaces the
Santa Ana winds. By the middle of next week, an area of low
pressure from the north will move over the Desert Southwest.
Though the path of this system remains uncertain, chances of
precipitation are in the forecast.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
This evening, sfc pressure gradients are still weakly offshore but
are trending onshore. The upper level ridge has been replaced by
troughing aloft. The height falls and cyclonic flow aloft will
likely cause the marine layer to deepen as onshore flow returns.
Patches of low clouds have formed over the coastal waters and have
begun to move onshore in northern San Diego County. High clouds
and drainage winds could still disrupt the formation of low clouds
so there isn't much confidence that we'll see much low cloud
coverage or fog tonight, although high resolution models indicate
significant cloud cover by sunrise Friday.
From previous discussion...
A weather system currently in the Pacific Northwest will continue
to push inland over the western part of the country, weakening and
displacing the area of high pressure over our region through the
weekend. This will lead to cooler weather with stronger onshore
flow. By the weekend, temperatures in most areas will be in the
60s and 70s, with 50s across areas above 5,000 feet. Chances for
low clouds and fog will increase over coastal areas into the
weekend as the marine layer deepens.
A low pressure system will move across the Great Basin by Sunday
and Monday, which will lead to a slight increase in offshore winds
for Monday. Depending on the strength of this pressure gradient,
temperatures may climb into the mid or even upper 70s for valleys
west of the mountains. A second weather system will move in from
the north around Wednesday of next week. Model projections show
quite a varied array of where the system will go. Some projections
point to a more inland scenario, where we would remain dry with
Santa Ana winds. Others point to a wetter scenario, where the
system moves closer to our area or off the ocean. NBM shows
increasing chances for precipitation around 15-30% by Wednesday
and Thursday of next week. Continue to keep an eye on the forecast
as our confidence grows on the path of this weather system and
how it could impact your area.
&&
.AVIATION...
280345Z....Coasts/Valleys...SCT-BKN high clouds AOA 20,000ft MSL
along with patchy cloud cover, mostly offshore, this evening. Low
cloud cover based 400-700 ft MSL will gradually spread into parts of
the coast overnight, with a 40-60% chance for CIGs at coastal sites
overnight (highest chances after 08Z KSAN, 10Z KCRQ, and 14Z KSNA).
Localized VIS reductions down to 3-5SM possible during this time as
well, 0-2 SM for elevated coastal terrain impacted by clouds. Any
low clouds clearing to the coast 15-17Z, except for parts of
northern Orange Co where clouds could persist through 18Z. More
widespread low clouds 600-900 ft MSL spreading into coastal areas up
to 15 miles from shore after Sat 02Z.
.Mountains/Deserts...VFR conditions expected through the TAF
period. High clouds SCT-BKN AOA 20,000ft MSL through tonight.
&&
.MARINE...
No hazardous marine conditions are expected through Tuesday.
&&
.SKYWARN...
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&
$$
PUBLIC...PG
AVIATION/MARINE...CSP
Office: MTR
FXUS66 KMTR 280421
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
821 PM PST Thu Nov 27 2025
...New UPDATE, MARINE...
.KEY MESSAGES...
Updated at 1235 PM PST Thu Nov 27 2025
- Warm temps for areas south of San Jose, Tule fog keeping temps
cooler further north.
- Persistence forecast for the next several days (not much change
in day-to-day)
- No precip in the forecast. Need to look towards the middle of
the month for next chance.
&&
.UPDATE...
Issued at 816 PM PST Thu Nov 27 2025
Not much to update on tonight. Fog is creeping into the East Bay
and North Bay valleys, but the temperature fluctuations from high
clouds moving into the area along a weak boundary could cause
some interruptions in fog formation further into the night.
However, the overall fog chances remain strong for those areas,
and any interruptions will be shot lived.
-Murdock
&&
.SHORT TERM...
Issued at 1235 PM PST Thu Nov 27 2025
(This evening through Friday)
~gobble gobble~
Sun for most and really frustrating stratus and Tule fog for a few
others. Forecast today remains mostly on track, except
temperatures in the North Bay and inland East Bay where I've
lowered high temps to account for the lingering fog and stratus.
Notable places like Santa Rosa, Napa, and Livermore have barely
broken 50 degrees as of 1-2pm. This pattern is likely to persist
into tomorrow.
&&
.LONG TERM...
Issued at 1235 PM PST Thu Nov 27 2025
(Friday night through next Wednesday)
The persistence forecast is a good bet for the next few days as a
very high amplitude ridge builds into the Gulf of Alaska and
promotes downstream troughing into the continental US. This
pattern results in light offshore flow for our region, which will
mostly keep temps mild and skies mostly dry. On that note, there
is no precipitation in our forecast through the next seven days.
&&
.AVIATION...
(00Z TAFS)
Issued at 425 PM PST Thu Nov 27 2025
Currently VFR with potential for fog and stratus to return tonight.
Moderate to high confidence in stratus reaching STS, APC, and LVK
tonight with some potential for lowered visibilities and ceiling
heights throughout the rest of the Bay Area. The marine layer looks
to deepen to around 1200 ft tonight which may bring in some stratus
coverage along the coastline. Highest confidence that stratus will
reach HAF but some may reach MRY early tomorrow morning as well.
Winds generally stay light and offshore overnight before becoming
light and onshore during the day tomorrow.
Vicinity of SFO...VFR through the rest of the evening. Given the
current fog/stratus setup, continued to lean towards a persistence
forecast with MVFR-IFR conditions developing at least temporarily
tomorrow morning.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR. Some potential for MVFR CIGs at MRY
early tomorrow morning as stratus returns along the coast.
Confidence is too low to include in TAFs with models keeping the
stratus directly along the coastline/away from the airport.
&&
.MARINE...
(Tonight through next Wednesday)
Issued at 816 PM PST Thu Nov 27 2025
Moderate north to northeasterly winds continue through Friday as a
weak front moves through the northern waters. Localized fresh
winds are expected south of Point Pinos tonight into Saturday.
Winds will decrease early Saturday before increasing late
Saturday into early next week. Hazardous marine conditions return
midweek as a cut-off low moves through the coastal waters with
winds increasing and wave heights building due to incoming long
period westerly swell.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM to 9 PM PST Friday for Pigeon Pt
to Pt Pinos 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.
&&
$$
SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...Kennedy
MARINE...Kennedy
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