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Office: EKA
FXUS66 KEKA 290858
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
1258 AM PST Sat Nov 29 2025

.SYNOPSIS...A mid period westerly swell will bring a moderate
risk for hazardous beach conditions Saturday afternoon. A much
more energetic westerly swell group will bring a high risk for
sneaker waves Monday through Tuesday next week. Otherwise, dry
and seasonably cool weather is forecast for the next 7 days.


&&

.KEY MESSAGE...

* Dry and seasonably cool weather expected through the next
  7-days, with a mix of sunshine and clouds.

* A Moderate Risk of sneaker waves risk is expected along the
  Northwest California beaches this afternoon and early evening.

* Sneaker Waves risk increases to High on Monday and continue
  through Tuesday.

* Blustery north and east-northeast winds over the ridges Tuesday
  night into Wednesday.


&&

.DISCUSSION...Latest GOES-West satellite imagery depicts stratocumulus
continuing to stream eastward across the area, while coastal low
clouds persist overnight. Despite the high-level cloud cover, chilly
overnight temperatures in the mid to low 30s have been observed
in Trinity, portions of interior Mendocino and Lake counties.
Southern Lake County have not seen a widespread killing freeze yet
this Fall. A Frost Advisory is now in effect until 9 AM this
morning for southern Lake County. Dry weather and seasonably
temperatures continue today, with a mix of sunshine and clouds.

A semi-stationay upper-level ridge over the northeastern Pacific
will act as a blocking pattern through the next 7-days, forcing
any "inside slider" weather disturbance to track southward from
the Pacific NW. A dry shortwave trough will swoop down across the
Pacific NW into the Great Basin over the weekend and serve to re-
establish an offshore wind regime across the area by Sunday. Breezy
northerly winds will develop along the coastal headlands and
exposed ridges by Sunday. Offshore winds are expected to develop
over the higher terrain across the interior Sunday evening and
increase into Monday morning, with the strongest winds anticipated
over the eastern portion of Lake County where gusts up to 25-35
mph are possible. Frost and freezing morning temperatures will
also be possible. Average low temperatures for this time of year
are in the low to mid 30s in the interior valleys and agricultural
interests have ended. Frost and freezing morning temperatures
could kill tender plants left outside in the cold.

A third shortwave trough may (18% chance) generate a few fleeting
light showers or sprinkles for Del Norte and mountains of Trinity
Monday-Tuesday. This shorter wavelength trough will carve out a
larger scale trough that will head southward over central and
southern Cal by Wednesday. Another possible outcome is for the
trough to dig much farther east over the Great Basin with a
massive ridge aloft taking hold over the forecast area by
Wednesday. Blustery N and E-NE winds will develop Tuesday night-
Wednesday for the higher terrain and perhaps Lake County. E-NE
wind gusts to 35-45 mph will be possible over the ridges. The air
mass is not forecast to be exceptionally cold next week either.
With dew points in the 20s, calm winds in the valleys and clear
skies overnight, frost and freezing temperatures will once again
crop up for areas that have not had a so called killing freeze
yet. Fog and low clouds will no doubt (a 100% chance) be a nightly
occurrence in the interior river valleys, especially Humboldt and
Trinity. Cold weather advisories for wind chill may also be
necessary for wind gusts around 10-15 mph. Our long stretch of dry
cool weather may finally come to an end late next week. All
global ensemble systems indicate increasing probabilities for 0.10
inches of precip in 24hr over multiple days from Dec 6 to Dec 8.


&&

.AVIATION...06z TAFs...Ceilings have gradually dropped through the
evening, with mostly MVFR ceilings along the coast around midnight.
There is high model disagreement on the exact evolution of conditions
into Saturday morning. Most models show at least borderline IFR to
MVFR ceilings through the early morning, especially around Humboldt
Bay, with IFR to LIFR fog for many interior valleys including Ukiah.

 Interior conditions will most likely quickly clear after sunrise.
Most ensemble members show lifting to MVFR or VFR along the coast
during the day Saturday, but about 30% of models show MVFR ceilings
more persistent through the day. A weak trough passing to the north
may help lift ceilings Saturday night, but will also promote onshore
flow conducive to marine layer formation. With those two competing
forces, ensembles continue to show uncertain and mixed conditions,
but with little potential for widespread, disruptive LIFR
conditions. /JHW


&&

.MARINE...Weak to moderate northerly winds have built in all across
the waters. Northerly winds will continue to increase in the outer
waters with near gale force gusts in the southern outer waters
Sunday gradually spreading northwards. North winds and steep short
period seas will stay restricted to the outer waters and will
briefly weaken again around Monday. There is strong agreement,
however, that north winds will push back closer to shore around mid
next week with periods of strong gale force gusts.

Aside from the winds, a minor mid period westerly swell will build
up to around 8 feet late Saturday into Sunday, but this swell will
quickly decay. Another, much longer period swell will build around
Monday into Tuesday up to around 12 feet. Neither swell will be
particularly steep but will dominate the inner water sea state where
short period seas are calm. /JHW


&&

.BEACH HAZARDS...A series of mid period westerly swells will
continue to impact the waters through the weekend. The next swell
will build up to 8 feet at 14 seconds beginning Saturday afternoon
into Sunday. With mostly calm short period seas, the forerunners of
this swell especially will pose a moderate sneaker wave risk
Saturday evening with unexpected and inconsistent surf on area
beaches Saturday afternoon.

A second, stronger sneaker wave risk is possible as longer period
swell builds Monday into Tuesday. The very long period of this swell
up to 22 seconds will make waves particularly deceiving with the
swell likely to build in rapidly with little warning. Short period
seas building closer to shore will lessen the overall risk by around
mid week. /JHW


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Beach Hazards Statement Saturday afternoon for CAZ101-103.

     Beach Hazards Statement from Saturday afternoon through
     Saturday evening for CAZ104.

     Beach Hazards Statement from Saturday afternoon through
     Saturday evening for CAZ109.

     Frost Advisory until 9 AM PST Saturday for CAZ115.

NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory from 11 AM to 11 PM PST Sunday for
     PZZ455-470.

     Small Craft Advisory from 11 PM Saturday to 5 AM PST Monday
     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.

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Office: HNX FXUS66 KHNX 290802 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 1202 AM PST Sat Nov 29 2025 && .KEY MESSAGES... 1. Stratus will continue to hang around through most of Saturday. 2. Trough slides to the east late Saturday through Tuesday. Winds increase but will bring no precipitation to the area. 3. A second trough slides down Tuesday through Thursday. Precipitation chances increase for this trough. && .DISCUSSION... Stratus has continued to hang around which kept temperatures cold again yesterday. However, ensembles show the ridge crumbling and breaking as two troughs are in play. One of them becomes a cutoff low later today but will spin offshore and move away towards Hawaii. However, the other trough we have been keeping an eye on will also begin sliding in later today through the weekend. This trough will help increase wind gusts by a few miles per hour but not to Advisory level or cause Mono winds for our area. This trough moves east quickly and will not bring any rain or snow to our area. The next chance of rain and snow is another trough which slides down late Tuesday through Thursday. However, models diverge around Thursday as to whether this trough will become a cutoff low or move east. Latest probabilities have a 5 percent chance or less of an inch of snow in the Sierra Nevada with this storm and a 20 to 25 percent chance of any rain accumulating in the Valley Thursday into Friday. && .AVIATION... IFR to MVFR ceilings and visibilities will persist in most Valley locations through 18Z Saturday. However, after 18Z, conditions are expected to improve although there is a 40 to 60 percent chance of ceilings at or below 1,000 feet until 21Z. After 21Z, there is a 35 to 45 percent chance of ceilings below 3,000 feet. && .AIR QUALITY ISSUES... ISSUED: 11/28/2025 13:33 EXPIRES: 11/29/2025 23:59 On Saturday November 29 2025, Unhealthy for Sensitive Groups in Fresno and Kern Counties. Fireplace/Wood Stove Burning Status is: No Burning For All in Fresno and Kern Counties. No Burning Unless Registered in 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 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 8 AM PST Saturday for CAZ335. && $$ JPK weather.gov/hanford
Office: LOX FXUS66 KLOX 291710 AFDLOX Area Forecast Discussion...UPDATED National Weather Service Los Angeles/Oxnard CA 910 AM PST Sat Nov 29 2025 .SYNOPSIS...28/1149 PM. Dry weather will continue at least through next Tuesday. A cooling trend will continue through the weekend as onshore flow returns. Gusty Santa Ana winds are possible Monday with warmer temperatures. Then turning cooler Tuesday followed by a chance of rain Wednesday. && .SHORT TERM (TDY-MON)...29/909 AM. Some low clouds and patchy dense fog remain across the coastal areas this morning, but clouds are starting to clear as the marine inversion lifts out. Mainly high clouds will stream over the area today as high-level moisture flows over the top of shortwave ridge. A return of low clouds and fog is expected for most coastal areas and some valley areas tonight and into Sunday as tick up of onshore flow should allow for a bit more coverage tonight. A cooling trend will likely continue into Sunday as broader troughing will replace the shortwave ridge. ***From Previous Discussion*** A weak inside slider will move over the area Sunday night and set the stage for a Santa Ana wind event Monday. There should be about 5 mb offshore flow from the east with about 3 from the north. There is some upper support at 850mb and a little cold air advection as well. These ingredients will combine to bring a moderate Santa Ana with advisory level gusts (40-50 mph) likely through the Santa Ana Wind Corridor in the morning. The cool air advection will not allow for a big warm up - only 2 to 4 degrees across the csts/vlys. The interior will see cooling as the offshore flow brings in colder air from the N and E. The Antelope Vly will see the most cooling: 5 to 10 degrees. Skies should be mostly sunny except for the Long Beach area, western SBA county and the Paso Robles area where the offshore flow will be too weak to prevent low cloud formation. .LONG TERM (TUE-FRI)...29/1231 AM. Dry NW flow sets up on Tuesday. The offshore flow in the morning will be much weaker and by afternoon there will be an onshore push to the east. There will likely be some non advisory level NE winds in the morning. The day will start off sunny but by he afternoon it will be partly clouds as some high clouds stream in. A typical post Santa Ana day as far as temps go with cooling at the csts/vlys due to weaker offshore flow and warming across the interior as the cool air advection shuts off. Still not much mdl agreement for the Wed/Thu time period. An impulse will slide out of Canada and will either turn into a fairly sharp inside slider that is a little more westward than usual (GFS) or cool cut off low that retrogrades over SBA county. Looking at all of the ensembles about 25 percent of them favor rain with the best chc over LA county. There is about a 50 percent chc that some rain will fall over the entire 2 day period. Rainfall amounts (if any) will not amount to much likely under a quarter inch. Other solutions just bring some winds to the area. Definitely cooler Wednesday. Most ensembles favor warming Thursday but if the EC verifies the max temps will not change much. Friday should be dry. It looks like another Santa Ana will develop but it will be at worst a moderate one. Max temps should warm with the offshore flow and should be close to normals. && .AVIATION...29/1707Z. At 1700Z at KLAX, the marine layer was around 600 feet deep. The top of the inversion was 1800 feet with a temperature of 16 degrees Celsius. For 18Z TAF package, moderate to high confidence in forecasts. High confidence in VFR conditions for KBUR, KVNY, KWJF and KPMD. For coastal sites, moderate confidence in current forecasts due to uncertainties with the behavior of the marine layer. Timing of flight category changes could be +/- 4 hours of current forecast with flight categories off by 1 category. KLAX...Moderate confidence in 18Z TAF. Timing of flight category changes could be +/- 4 hours of current forecasts. Also, there is a 40% chance of LIFR conditions 08Z-14Z. No significant easterly wind component is expected. KBUR...High confidence in 18Z TAF. && .MARINE...29/907 AM. For the Outer Waters, moderate to high confidence in current forecast. Through tonight, high confidence in winds and seas remaining below Small Craft Advisory (SCA) levels. For Sunday, there is a 40-50% chance of SCA level winds, mainly across PZZ670/673. For Monday through Wednesday, there is a 30-40% chance of a combination of SCA level winds and seas. For the Inner Waters north of Point Sal, high confidence in current forecast. Winds and seas are expected to remain below SCA levels through Wednesday. For the Inner Waters south of Point Conception, high confidence in current forecast. Winds and seas are expected to remain below SCA levels through Wednesday. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...Hall/Rorke AVIATION...RAT MARINE...RAT SYNOPSIS...MW/CC weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox
Office: STO FXUS66 KSTO 282219 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 219 PM PST Fri Nov 28 2025 .KEY MESSAGES... - Dry conditions and possible periods of morning Valley and adjacent foothills fog and mist continue through the weekend - Below normal temperatures and low clouds continue in the Valley, Delta and lower foothills through the weekend, with sunny skies and above normal temperatures in the upper foothills and mountains - Decreasing chances for precipitation with just a slight chance of showers south of I-80 mid week. - Periodically breezy north to east winds expected late Sunday and again Wednesday && .DISCUSSION... ...Today - This Weekend... Current GOES-West imagery shows a broad stratus deck continuing to cover the Delta, Valley, and adjacent lower foothills this afternoon. This cloud coverage has kept temperatures quite cool in those areas today, 10-15 degrees below normal for this time of year, while higher elevations have been sunny and mild. The low clouds also greatly limited the development of fog last night into this morning. The patchy fog that developed over the lower Motherlode foothills and for portions of the northern Sacramento Valley diminished by mid- morning, with some mist and haze persisting into the afternoon. Dense fog may return to some portions of the area this evening into Saturday morning, but the persistent low cloud cover will likely be a limiting factor again for fog development. Probabilities of fog (visibilities less than a half-mile) currently sit around 50 to 70 percent for the northern and central Sacramento Valley and the lower foothills, while the Delta, southern Sacramento Valley, northern San Joaquin have probabilities around 30 to 40 percent. Aside from periodic fog development and low clouds, cool Valley/Delta temperatures and dry weather are expected to persist through the weekend. ...Next Week... Breezy north to east winds will be possible late Sunday into Monday, around 20 mph in the Valley, with the strongest wind gusts up to 35 mph expected along the Sierra. With a more persistent offshore(north-east) wind pattern setting up late weekend into next week, fog development is expected to be less relative to this past week. More normal temperatures are expected with less low cloud coverage over the Valley. Ensemble guidance then indicates some potential for an inside slider type system dropping into the Great Basin, bringing the potential for breezier north to east winds and another slight chance for mountain showers will be possible. Currently these showers look light and limited to the Sierra south of I-80. && .AVIATION... MVFR conditions linger at TAF sites in BR/low stratus through the afternoon and early evening, with IFR/LIFR conditions returning in areas of FG/BR and low stratus cigs after 06z. Light and variable winds expected to persist at low elevations next 24 hours, with breezy, downsloping east winds along the Sierra after 06z. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$
Office: SGX FXUS66 KSGX 291658 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 858 AM PST Sat Nov 29 2025 .SYNOPSIS... Cooler and dry this weekend. Patchy fog along the coast this morning, then increasing coverage tonight into Sunday morning. Weak Santa Ana winds develop Monday and weaken Tuesday for warmer and drier weather. There is a 20-35% chance of light precipitation Wednesday into Thursday, though confidence remains low. Another round of offshore winds will follow this system late in the week. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... Morning Update... While lingering marine layer clouds are present in Orange County this morning, these should continue to clear out over the next hour or so as the clouds across coastal San Diego County have. Other than some high clouds this afternoon, mostly sunny skies expected across the region today with temperatures right around normal for late November. For more details about the forecast through mid-next week, refer to the previous discussion. Previous Discussion... An upper level trough will drop out of the Pac NW and into the Great Basin late today into Sunday. This will bring cooling with highs returning closer to seasonal normals. Gusty west winds will also develop as onshore pressure gradients strengthen, with gusts around 35-45 mph in the wind prone passes and the desert slopes of the mountains. Gradients quickly turn offshore on Monday as high pressure settles into the Great Basin behind the trough. There will be modest upper level support in the form or northerly winds behind the digging trough (850 mb winds of 15-20 kt), albeit briefly. Winds are currently forecast to peak on Monday when gusts of 30-45 mph are likely below the passes and canyons and into the valleys, with isolated gusts around 50 mph near the Cajon Pass and Santa Ana Mountains. Otherwise warmer west of the mountains but cooler elsewhere on Monday. Offshore flow weakens and turns back onshore on Tuesday ahead of the next system for cooling and lighter winds. The upper level pattern is still questionable beyond Wednesday with the next trough dropping down from the north. Ensembles remain inconsistent with how far southwestward the trough digs, which impacts how much (if any) precipitation we'll see. For Wednesday, around 58% of the ensemble members bring the low far enough west for at least light precipitation late the evening. By Thursday, 32% keep a weak positively tilted trough over the area (light precipitation), 25% have the track inside (dry), 22% develop a closed low off the coast (relatively heavier precipitation), and 21% have a weaker low closer to the Colorado River Valley (lighter precipitation at the coast but heavier inland). Even into Friday, 48% of the members keep a closed low somewhere in the vicinity of So Cal while the remaining 52% have a weaker open wave inland. With the closed low solution, we could continue to see cooler weather and light precipitation if the low is close enough, or with the more progressive/inside track it'll be another round of Santa Ana winds and warmer and drier weather. For what it's worth, the ECMWF AIFS ensemble, which has been performing fairly well, is much drier on Friday than its EPS and deterministic counterparts. For now just have the slight chance to chance (15-35%) PoPs limited to Wednesday morning through Thursday evening, then slightly warmer and dry weather Friday and Saturday. && .AVIATION... 291600Z....Coasts/Valleys...Very patchy areas of low clouds based 300-700ft MSL remain across coastal regions with VIS between 1/4-2SM but are quickly clearing, with VFR everywhere expected beyond 18z. Very patchy low clouds with similar bases and VIS will redevelop and move ashore after 02Z Sunday with similar to slightly more inland extent. A weak eddy may allow bases to rise a bit and clear out quicker Sunday morning, possibly by 13z. .Mountains/Deserts...VFR conditions expected through the TAF period. && .MARINE... No hazardous marine conditions are expected through Thursday. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...None. && $$ PUBLIC...Munyan AVIATION/MARINE...Zuber
Office: MTR FXUS66 KMTR 291807 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 1007 AM PST Sat Nov 29 2025 ...New AVIATION, MARINE... .KEY MESSAGES... Updated at 139 AM PST Sat Nov 29 2025 - Mild and quiet, beautiful weather through the weekend. - Pattern continues into much of next week. Breezy offshore winds in the North Bay interior Wed/Thu. Minimal impact. - Hazardous beach conditions through early next, which will include sneaker waves, rip currents, and breaking waves 13 to 18 feet. - King Tides arrive December 2 - 7 and may lead to coastal flooding. && .SHORT TERM... Issued at 139 AM PST Sat Nov 29 2025 (Today and tonight) No major changes to the forecast for today outside of high temperatures in the North and East Bay. The reason being, we're expecting stratus and Tule fog to persist across the region, keeping temperatures regulated. Highs on Friday for these regions peaked in the upper 40s to low 50s, though if there was clearing, the mid to upper 50s were observed. Expect that to the be the case again today for those regions and San Francisco, with warmer temperatures elsewhere especially the Central Coast, where some upper 60s to low 70s will be possible. Stratus and fog should return again tonight, leading to another mild night with temperatures near or just above normal for this time of year. && .LONG TERM... Issued at 139 AM PST Sat Nov 29 2025 (Sunday through Friday) More quiet weather is on tap through the extended forecast, with cluster analysis showing weak ridging to semi-zonal flow through Tue. Guidance then shows an upper level low, similar to an inside slider type situation Wed into Thu favoring breezy offshore winds for interior N Bay counties. Models then struggle for the late portion of the work week and weekend and where that low goes and if upper level high pressure can nose into the area. Right now, guidance continues to keep us dry. && .AVIATION... (18Z TAFS) Issued at 1005 AM PST Sat Nov 29 2025 A mix bag of LIFR to VFR conditions this morning depending on where you are. Conditions are forecast to gradually improve to VFR by late morning or early afternoon, the exception being across the North Bay and far interior portions of the East Bay. There is a low potential for IFR/MVFR ceilings and/or visibilities to linger through much of the day across the North Bay and East Bay. Also, passing high clouds will persist through much of the TAF period. Low ceilings and/or visibilities return late tonight and into Sunday morning before clearing by midmorning or early afternoon. Vicinity of SFO...MVFR (KSFO) to VFR (KOAK) currently. Conditions are forecast to improve to VFR by late morning and continue through the evening. IFR/MVFR ceilings expected to return across KSFO early Sunday morning with a later return to KOAK. Ceilings and/or visibilities improve to VFR by midmorning or early afternoon Sunday. SFO Bridge Approach...Expecting an earlier return across the approach of IFR/MVFR ceilings Sunday morning. Otherwise, similar to SFO. Monterey Bay Terminals...VFR. Onshore winds will increase slightly this afternoon before diminishing after sunset. There is low confidence for sub-VFR conditions early tomorrow morning. Drainage winds likely in the Salinas Valley early Sunday morning before turning onshore by Sunday afternoon. && .MARINE... (Today through Thursday) Issued at 1005 AM PST Sat Nov 29 2025 Gentle to moderate northerly breezes will gradually develop by Sunday with strong gusts over the outer waters. Hazardous marine conditions return Sunday with building swell heights. Winds increase and wave heights build due to incoming long period westerly swell in the mid work week. && .BEACHES... Issued at 139 AM PST Sat Nov 29 2025 Moderate to long period northwesterly swell will result in an increased risk for sneaker waves and rip currents. Breaking waves of 13 to 18 feet are expected. A beach hazards statement is in effect for the coastline from Sonoma County to Monterey County through 10 PM PST Sunday evening. 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. Dangerous beach conditions look to continue into early next week, though there is some uncertainty as breaking wave heights flirt with High Surf Advisory criteria. Stay tuned, as and remember, never turn your back to the ocean. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...Beach Hazards Statement through Sunday evening for CAZ006-505- 509-529-530. PZ...Small Craft Advisory from 3 AM Sunday to 3 AM PST Monday for Pt Arena to Pt Reyes 10-60 NM. Small Craft Advisory from 3 PM Sunday to 3 AM PST Monday for Pigeon Pt to Pt Pinos 10-60 NM. && $$ SHORT TERM...KR LONG TERM....KR AVIATION...RGass MARINE...RGass 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