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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 272240 AFDLOX Area Forecast Discussion...UPDATED National Weather Service Los Angeles/Oxnard CA 240 PM PST Thu Nov 27 2025 .SYNOPSIS...27/1114 AM. 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 (TDY-SUN)...27/1135 AM. 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...27/1717Z. Around 1614Z at KLAX, there was no marine layer. There was a sfc- based inversion with a top near 800 ft and a temperature of 23 C. Overall, high confidence in 18Z TAF Package. Except for KPRB which has a 40% chc of V/LIFR conditions from 12Z to 17Z Friday, & KLGB with similar odds of LIFR conditions from 12Z to 16Z Friday. KLAX...High confidence in VFR TAF through 12Z Friday. low chance (10%) of LIFR CIGs 13Z-18Z Friday. Good confidence in any east wind component remaining below 7-8 knots through forecast period. KBUR...High confidence in VFR TAF. && .MARINE...27/239 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 AVIATION...Black MARINE...Black SYNOPSIS...MW 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 272043 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 1243 PM PST Thu Nov 27 2025 .SYNOPSIS... A cooling trend will ensue from Friday into the weekend, most notably for the mountains and western valleys, as high pressure weakens over the region. An area of low pressure from the north will move over the Desert Southwest by the middle of next week. 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... Offshore flow continues to subside with gusts mainly below 30 MPH across the mountains and adjacent foothills. High clouds this afternoon will begin to scatter out tonight with patchy shallow low clouds nearing the coast at times. A weather system currently in the Pacific Northwest will continue to push inland over the western part of the country, helping to weaken the area of high pressure over our region through the weekend. This will lead to cooler weather with greater onshore flow. By the weekend, most areas will be in the 60s and 70s, with 50s across areas above 5,000 feet. Chances for fog will increase near coastal areas into the weekend as well 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 by 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 secondary 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... 272030Z....Coasts/Valleys...VFR prevailing with SCT-BKN high clouds AOA 20,000ft MSL. Patchy low clouds develop offshore tonight, with a moderate chance (35-50%) of brief impacts at KSAN with bases around 500-800ft MSL and a 30% chance at KSNA or KCRQ. Highest chances for impacts will be between 11-17z Fri. Localized VIS reductions down to 3-5SM possible during this time as well, with possibly lower for coastal terrain. Any clouds that made it ashore will filter back to the coast by 18-19z. .Mountains/Deserts...VFR conditions expected through the TAF period. High clouds SCT-BKN AOA 20,000ft MSL prevailing 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...APR AVIATION/MARINE...Zuber
Office: MTR FXUS66 KMTR 272247 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 247 PM PST Thu Nov 27 2025 ...New SHORT TERM, LONG TERM... .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. && .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... (18Z TAFS) Issued at 1003 AM PST Thu Nov 27 2025 Another challenging morning for aviation with slow clearing of clouds and fog for the N and E Bay. Additionally, another pesky finger of clouds impacts SFO with a slow clearing there too. IFR conditions will linger for the N and E Bay into the afternoon. Other terminals will be VFR to MVFR (haze/br). For tonight, took a blend of HRRR lo clouds and persistence from the last few nights. Expect another night of IFR to MVFR most areas. Overall conf is low to medium. Vicinity of SFO...IFR cigs through 1830-19Z then VFR. Will bring IFR cigs back late tonight with a 60-70% conf. SFO Bridge Approach...Similar to SFO with cigs over the approach through 19Z. Monterey Bay Terminals... VFR. && .MARINE... (Today through Tuesday) Issued at 1003 AM PST Thu Nov 27 2025 A weak dissipating cold front will enter the coastal waters later today. As such, moderate to fresh northerly winds will develop lasting into Friday. Winds will decrease Saturday but pick up to a moderate to fresh north breeze on Sunday, with lighter winds expected for the early part of next week. && .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. Small Craft Advisory from 9 PM this evening to 9 PM PST Friday for Pt Pinos to Pt Piedras Blancas 0-10 nm. Small Craft Advisory until 9 AM PST Friday for Pt Arena to Pt Reyes 10-60 NM. Small Craft Advisory until 9 PM PST Friday for Pigeon Pt to Pt Pinos 10-60 NM. && $$ SHORT TERM...Behringer LONG TERM....Behringer AVIATION...MM MARINE...MM Visit us at www.weather.gov/sanfrancisco Follow us on Facebook, X, and YouTube at: www.facebook.com/nwsbayarea x.com/nwsbayarea www.youtube.com/nwsbayarea