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Office: EKA
FXUS66 KEKA 070826
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
1226 AM PST Sun Dec 7 2025

.SYNOPSIS...Cloudy and misty conditions expected this morning. A
warm front with light rain and drizzle passes over Del Norte and
Humboldt counties today. Generally dry weather conditions is
expected to prevail across NW CA this coming week, with periods of
light rain/drizzle for the North Coast.

&&

.DISCUSSION...A stubborn high pressure center has been sitting off
the California coast for a few weeks now. The strength of the high
pressure has been keeping the storm track far to the north of NW CA
for the last few weeks. This slower start to winter will continue
this week with increased moisture, yet not enough forcing will be
present to create meaningful precipitation amounts as most of the
vertical vorticity of a frontal system to the north will be
focused in Oregon, only briefly and periodically clipping NW CA.
The increased atmospheric moisture will create fog and low clouds
along the coast and in the inland valleys. Increased cloud
coverage will keep nighttime temperatures on the warmer side for
the season.

A passing warm front will bring light rain and/or drizzle across
mostly Del Norte and Humboldt counties later today. Total storm
precipitation amounts will be minimal and mostly north of Humboldt
Bay and West of the Klamath River. REFS probabilities shows only a
20-30% chance of wetting rain in Del Norte and a 0-15% chance of
wetting rain in northern Humboldt Co. Elsewhere, drier weather
conditions will prevail with morning valley fog, mist and low
clouds.

High pressure slowly builds back over the area next week in the wake
of the frontal passages. The general consensus between the ensemble
and operational models is dry weather conditions across much of
Northwest California, with intermittent light rain/drizzle in Del
Norte County through Thursday at the earliest. The dry weather
allows for a gradual warming trend through the week, with interior
high temperatures warming up to mid 60s to mid 70s late in the week
peaking on Thursday.

Some ensembles are indicating a pattern change by mid December but
there is a large amount of uncertainty as it is too far out in time
to have any true meaning for the forecasts.
-ZVS/DES


&&

.AVIATION...(06Z TAFS)...Periods of LIFR to IFR stratus will
continue into early Sunday for coastal areas ahead of an approaching
front. Light rain is possible over Humboldt and Del Norte starting
early Sunday morning around 12Z. Some interior valleys may see
stratus and fog again tonight, but confidence at UKI is lower. JB


&&

.MARINE...Northerly winds and seas have eased as front moves in
north of our area. Generally light winds are forecast this weekend,
with south winds forecast north of Cape Mendocino and west-northwest
winds forecast south of the Cape. A mid period northwest swell will
continue and peak at around 7-9 ft at 12 seconds. Wave heights peak
early Sunday morning. Combined seas could briefly reach or exceed 10
ft, especially if the swell fills in higher than forecast. Seas
subside Sunday and Monday as this swell decays. Light winds continue
into early next week, but seas will remain elevated as a series of
mid-period northwest swells fill in from systems to the north. JB


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
None.
&&

$$

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 070659 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 1059 PM PST Sat Dec 6 2025 .UPDATE... AQ and Aviation Updated && && .KEY MESSAGES... 1. Fog and low clouds will continue each night and morning across the San Joaquin Valley into early next 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... Overcast conditions continue to linger over the San Joaquin Valley this morning, with foggy conditions and low visibilities in the foothill areas where the cloud deck is interacting with the local terrain. Clearing is less favorable today compared to previous days due to a prominent high pressure ridge building in from the west. This ridge will maintain the low level temperature inversion currently in place for much of the day, keeping the moisture trapped around one thousand feet above ground level. With minimal clearing, fog has less potential for tomorrow morning in the valley areas, with less than a 30 percent chance for visibilities less than a quarter mile. These chances improve to 50 to 60 percent for the foothill areas of the Sierra Nevada, Kern County Mountains, and the Coastal Range. This pattern is expected to continue through the weekend as the high pressure remains present over the region. As we move into next week, cluster analysis expresses confidence in the high pressure strengthening over central California. As the high pressure builds, a warming trend will take place, especially in the area mountains and foothills where afternoon highs will rise well above season averages. By Wednesday, areas including (but not limited to) Oakhurst, Tehachapi, and Three Rivers have a 50 to 60 percent probability to exceed 65 degrees, some five to ten degrees above season average. Yosemite Valley, which averages around 45 degrees at this time of year, has a 70 to 80 percent probability to exceed 70 degrees Wednesday, Thursday, and Friday of next week. && .AVIATION... IFR to MVFR ceilings and visibilities are expected to prevail for much of the San Joaquin Valley. These conditions will continue through 18Z Sunday. LIFR conditions will also persist in the coastal ranges, Sierra foothills, and the Kern County mountains due to the low stratus deck. Otherwise, VFR conditions will prevail in the Sierra Nevada and in the Kern County Mountains and Desert over the next 24 hours. && .AIR QUALITY ISSUES... ISSUED: 12/06/2025 15:02 EXPIRES: 12/07/2025 23:59 On Sunday December 7 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 11 AM PST Sunday for CAZ300-335. && $$ public...SM aviation....JPK weather.gov/hanford
Office: LOX FXUS66 KLOX 071103 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 303 AM PST Sun Dec 7 2025 .SYNOPSIS...07/1212 AM. Benign weather will continue through the weekend with a small chance of morning low clouds and fog along the Los Angeles coast. A significant warming trend will begin today with temperatures well above normal Monday through next Friday, peaking Tuesday through Thursday. Offshore winds will increase Sunday and Monday, and are expected to persist through much of the week. && .SHORT TERM (TDY-TUE)...07/1239 AM. Benign weather on tap for the short term an beyond. Weak upper level ridging will continue and hgts will rise from 582 dam today to 586 dam on Tuesday. Offshore flow will also continue through the period, peaking on Tuesday. Skies should be mostly clear through the period with the exception of a 30 percent chc of some low clouds in the KLAX-KLGB area this morning and a more likely chc (~70 percent) chance on Monday morning. There will be local offshore winds each morning. Offshore flow increases each day and peaks on Tuesday. There is no chc of advisory level gust today and Monday but low end advisory level gusts look possible Tuesday morning through and below the Santa Lucia Range and the western LA vlys and eastern VTA vlys. Temperatures will be the main story. Rising hgts, offshore flow and sunny skies will all combine to bring 2 to 4 locally 5 degrees of warming each day. Max temps across the csts/vlys will rise from the upper 60s and 70s today to the the upper 70s to mid 80s by Tuesday. Most max temps will be 10 to 15 degrees above normal on Tuesday. Min temps will be warmer than normal in the windier areas, but the dry air and clear skies will bring lower than normal temps in the wind sheltered areas. .LONG TERM (WED-SAT)...07/300 AM. The GFS and EC as well as their ensembles all agree that the ridging from the west will continue through Friday. The upper high does weaken some and hgts will slowly fall during the 3 day period. The onshore flow which peaked on Tuesday will also slowly relax during the period. While there will be some morning canyon winds they will not be of much consequence. Still this forecast is all about the temps. Tuesday will be the warmest day for the csts of LA/VTA county as the relaxed offshore flow will lead 1 or 2 degrees of cooling on Wednesday. For the rest of the area, however, Wednesday will be the warmest day with max temps rising another 2 to 3 degrees over Tuesday's already super warm temps. Almost all areas will cool 1 to 2 degrees on Thursday as the high relaxes. Despite this cooling, most max temps will still end up 10 to 15 degrees over normal (4 to 8 for the nearshore area south of Pt Conception). Friday's temps will be similar to Thursday's. Not the best agreement on the pattern/fcst for next weekend, but in general the high should continue to weaken and offshore flow should weaken further. Some mdls show a return of the marine layer as well. Some cooling each day is likely, but how much is still a bit of a mystery. && .AVIATION...07/1019Z. Around 0815Z, there was no marine layer depth at KLAX, but there was a surface-based inversion up to around 2100 feet with a temperature around 17 degrees Celsius. High confidence in the current forecast for valley and desert terminals. Moderate confidence in the current forecast for coastal terminals. There is a moderate chance of VLIFR to LIFR conditions at Los Angeles County coastal terminals through 16Z. There is a moderate chance of VLIFR to LIFR conditions for coastal terminals after 08Z Monday. KLAX...There is a 30 percent chance of VLIFR to LIFR conditions through 16Z, and again after 08Z Monday. Any easterly winds will remain less than 7 knots. KBUR...VFR conditions are expected through the period. No wind impacts are expected at this time. && .MARINE...07/218 AM. Moderate confidence in the current forecast. Higher confidence exists in the forecast for winds versus seas. For the waters southwest through northwest of the Channel Islands beyond 10 NM offshore of the Central Coast, there is a high to likely (40 to 60 percent) chance of low-end Small Craft Advisory (SCA) conditions through the week, especially across the western portions during the afternoon and evening hours. Inside the southern California bight and for the nearshore waters along the Central Coast, there is a moderate to high chance (30 to 50 percent) of northeast SCA level winds from Ventura through Santa Monica and from Pismo Beach to Point Piedras Blancas each night and morning through Tuesday. Otherwise, winds and seas should remain below SCA levels. There is a moderate chance of dense fog over the coastal waters through Monday morning. Confidence remains low on timing and coverage. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...Small Craft Advisory in effect until 3 AM PST Tuesday for zones 670-673. (See LAXMWWLOX). && $$ PUBLIC...Rorke AVIATION...Hall MARINE...Hall SYNOPSIS...Black/Ciliberti weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox
Office: STO FXUS66 KSTO 062110 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 110 PM PST Sat Dec 6 2025 .KEY MESSAGES... - Periods of low 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 && .DISCUSSION... ...Today - Sunday... Stratus/Low clouds were more of the story this morning vs. fog dominating the forecast yesterday but still impacting much of the Central Valley and adjacent lower foothills. Out forecast remains on repeat with another round of low clouds/fog tonight into tomorrow morning with best chances Sacramento northward although fog is possible throughout all of the Valley. Dry weather and seasonable temperatures are forecasted for the region, with upper 40s to 50s in the Valley and foothills, and 40s to 60s in the mountains for the daytime highs. Highs are trending several degrees cooler than initially forecasted due to the persistence of the fog/low clouds, keeping max temperatures from being fully actualized. ...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 (mainly for areas outside of stratus/fog development). Dry conditions will continue through next week. Some ensembles are indicating a weak 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 continues into this evening, although some sites may very briefly return to VFR conditions around 22-24Z. Another round of BF/FG and low stratus returns tonight after 03Z and continues through Sunday, with areas of MVFR/IFR conditions. Areas of LIFR in fog and low ceilings around 12-18Z, particularly in the Central Valley from Sacramento southward. Lingering low ceilings in stratus expected to persist through the day. Light and variable surface winds less than 12kts. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$
Office: SGX FXUS66 KSGX 070954 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 154 AM PST Sun Dec 7 2025 .SYNOPSIS... Patchy low clouds and fog possible near the coast this morning and again tonight. Warm and dry through the week with periods of weak to locally moderate Santa Ana winds. Tuesday will likely be the warmest day with temperatures 15 to 20 degrees above seasonal averages in the inland valleys. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... A few thin patches of fog are developing over the coastal waters this morning with clear skies elsewhere. Surface dew points have been trending downwards along the coast with weak drainage flow, so chances of fog forming right along the coast are diminishing. The HREF has a 20-40% chance of dense fog over the coastal waters tonight into Monday morning, but coverage of any fog would be sparse. The upper level ridge of high pressure over the East Pac will strengthen but remain relatively stationary through Tuesday, then weaken slightly as it shifts eastwards over Western US through the end of the week. At the surface, persistent surface high pressure over the Great Basin will drive Santa Ana winds across So Cal through Saturday. Gradual warming takes place through Tuesday with the strengthening winds and increasing offshore flow, when highs will be as much as 10-20 degrees above normal. Widespread highs in the low to mid 80s is forecast across the inland coastal areas into the valleys as well as the low deserts. With winds being purely gradient-driven, they will be confined to the usual passes, canyons, and coastal slopes each night through early afternoon. The first peak in the winds is still forecast to be on Tuesday, though models have trended weaker with peak gusts now around 25-40 mph in the wind-prone areas. Weaker Santa Ana winds and the weakening high will allow for minor cooling Wednesday and Thursday, though highs remain around 10-15 degrees above normal inland. Ensembles are now showing another peak in Santa Ana winds on Friday, when surface pressure gradients are now forecast to be strongest this week. This will bring another bump up in high temperatures, mainly west of the mountains with highs once again nearing 20 degrees above normal in the valleys. Nights and mornings will remain cool, especially in the wind-sheltered areas, minimizing any heat impacts. The upper ridge continues to weaken next weekend, and weak offshore flow on Saturday will transition back to onshore flow on Sunday, bringing slow cooling through the weekend. By Sunday high temperatures will "only" be 8-13 degrees above normal inland. && .AVIATION... 070930Z....Chances for low clouds and fog development along the coastal locations have gone down from earlier with San Diego seeing chances of less than 10% and Orange County at 10-20% through 18Z this morning. Low clouds seem to be keeping their distance and staying out over the water for the time being. Chances begin to increase after 01Z Monday for patchy fog and low cloud development along the coast with the highest chances occurring after 04Z for San Diego County and after 09Z for Orange County through 18Z. Until then, VFR conditions are expected for all TAF sites. && .MARINE... Still a 10-20% chance of dense fog with visibility 1 nautical mile or less developing this morning through 11 AM. && .BEACHES... Morning high tide is predicted to be 6.5 around 10 AM this morning. Astronomically high tides may result in tidal overflow in normally dry beach areas. High tide is predicted to fall below 6 ft by Monday. && .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...SS AVIATION/MARINE/BEACHES...Villafane
Office: MTR FXUS66 KMTR 071157 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 357 AM PST Sun Dec 7 2025 ...New SHORT TERM, LONG TERM, MARINE, AVIATION... .KEY MESSAGES... Updated at 320 PM PST Sun Dec 7 2025 - Benign conditions through the next seven days with a gradual warming trend - Impacts from Tule Fog continue in the North Bay and interior East Bay valleys, with potential for expansion across the rest of the Bay Area tonight - Next chance for rain towards the middle of the month && .SHORT TERM... Issued at 321 AM PST Sun Dec 7 2025 (Today and tonight) Rinse and repeat kind of weather for the short term. Very similar to what was observed 24 hours ago in the broader scheme of things. Longwave pattern continues to show broad upper level ridging off the CA coast nosing its way into CA. A few high clouds are riding the northern periphery of the ridge. At the surface is where the impactful weather continues with and stratus covering the North Bay, East Bay, and portions of the Bay Area. Tule Fog is sneaking in from the Central Valley into the West Delta, North and East Bay. Patchy dense fog will be possible through mid morning with vsby less than one mile at times. The Central Coast on the other hand remains cloud free. Stratus didn't really clear yesterday over the North Bay so that is the question for today? Will Santa Rosa see some sunshine? Latest guidance says yes, but very late in the day. As such, undershot max temps from the NBM for the North and East Bay with highs struggling to reach 50 degrees. Other locations will see more sunshine and warming temperatures into the mid 50s and 60s. Expecting a similar pattern again tonight with some stratus and intruding Tule Fog. && .LONG TERM... Issued at 321 AM PST Sun Dec 7 2025 (Monday through Saturday) No major updates for the extended as we're locked in with this ridge of high pressure dominating the overall weather through at least next Friday. That means, some night and morning clouds like we've been having. Tule Fog will still advect into the Bay Area from time to time. The ridge is expected to build with higher heights. The stratus deck will compress with a gradual warming trend over the region. Still looking at 70 plus degrees across the Central Coast Tuesday through Friday. The amount of clouds cover over the North and East Bay will likely impact max temps and limit warming potential early in the week, but ease as the high pressure builds. Rain chances still exist for the middle of the month, but odds are decreasing. Latest CPC has backed off with near normal or below normal chances for precip through December 20. && .AVIATION... (12Z TAFS) Issued at 342 AM PST Sun Dec 7 2025 Tule fog pattern still strongly dominating the region. Based on persistence, low confidence in actually clearing for North Bay terminals. These areas have a slight chance of seeing IFR/LIFR all day again today. High confidence in clearing for Bay Area terminals (sans KLVK), but stratus and fog will be patchy through sunrise. Vicinity of SFO...Patch of stratus and fog moving along the peninsula likely to persist through sunrise, clearing to VFR in the few hours following. Otherwise quiet and clear through the afternoon with stratus returning this evening. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...High confidence in VFR through the TAF period. Light drainage offshore winds overnight with light onshore flow during the afternoons. && .MARINE... (Today through Friday) Issued at 321 AM PST Sun Dec 7 2025 Winds are reducing across the waters, but breezy northwest winds linger into the middle of next work week with the strongest winds focused on the southern waters. Moderate seas with wave heights 6 to 8 feet across the outer waters this weekend. A new, long period northwesterly swell is anticipated by Wednesday of next week. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...Coastal Flood Advisory until 3 PM PST this afternoon for CAZ006- 506-508-529-530. PZ...Small Craft Advisory from 3 PM Monday to 3 AM PST Tuesday for Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM. Small Craft Advisory from 3 PM this afternoon to 9 PM PST this evening for Pigeon Pt to Pt Pinos 0-10 nm. Small Craft Advisory from 9 AM this morning to 3 AM PST Tuesday for Pt Pinos to Pt Piedras Blancas 0-10 nm. Small Craft Advisory until 9 PM PST this evening for Pigeon Pt to Pt Pinos 10-60 NM. && $$ SHORT TERM...MM LONG TERM....MM AVIATION...Behringer MARINE...Behringer 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