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Office: EKA
FXUS66 KEKA 061002
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
202 AM PST Sat Dec 6 2025

.SYNOPSIS...Light rain possible for Humboldt and Del Norte late
through the weekend into early next week. King tides combined
with tidal anomaly will continue to bring the threat of coastal
flooding in low- lying areas around Humboldt Bay Saturday. A
series of frontal systems moving north of the area will bring a
chance of light rain across the northern portion of the area
through the weekend.



&&

.DISCUSSION...Dense fog developed Friday evening as radiational
cooling had a few hours of activity. Similar behavior is possible
Saturday morning with moisture being deposited from stratiform
saturated profiles near ground. The deep marine layer lifted as
the cold front approached as prefaced by the previous forecasts.
Light rain/drizzle is expected to continue into early next week.

High pressure continues to slowly weakening and "flattening",
while a series of shortwaves trough and frontal systems embedded
to the Aleutian Low continues to move toward the Pacific Northwest
this weekend. Northwest flow aloft will bring additional light
showers across Del Norte and Humboldt counties on Saturday. On
Sunday, another shortwave and frontal system is expected to move
north of our area. The flow aloft will become more zonal, bringing
additional chances of light rain across the northern portion,
especially for Del Norte and northern Humboldt counties.
Elsewhere, partly to mostly cloud skies is expected to continue.

The 500 mb ridge appears to slowly build back early next through
mid next week. WPC ensemble clusters do show about an even split
(50%) of clusters that are "drier" (at least for the North Coast)
than the grand ensemble mean. The ensemble mean is by no stretch
very wet with 0.10-0.25 inches of rain in 24 hours everyday from
Monday through Wednesday, mostly for Del Norte. It could be wet
or it could be dry or both. Stay tuned. -ZVS /EYS



&&

.AVIATION...(06Z TAFS)...A front will continue through Northwest
California early Saturday morning. Most of the drizzle and light
rain has moved through the area, but IFR/LIFR ceilings will continue
for coastal terminals of Humboldt and Del Norte counties.
Southeast flow ahead of another frontal passage to the north may
aide in lifting ceilings and visibilities around sunrise. For
areas to the south and east, including UKI, only a few high clouds
are expected with generally light winds. There is around a slight
chance for MVFR stratus impacts early Saturday to around sunrise
at UKI Saturday. Any low clouds and fog will lift and scatter
shortly after sunrise. JB


&&

.MARINE...Winds and seas continue to ease north of Cape Mendocino as
a weak front moves through the area. Winds and steep seas will
continue to ease early Saturday morning. Generally light winds are
forecast this weekend, with south winds forecast north of Cape
Mendocino and west-northwest winds forecast south of the Cape.
Despite light winds, seas will elevate as a mid-period northwest
swell fills in Saturday. This will peak at around 7-9 ft at 12
seconds. Wave heights peak Saturday night and early Sunday morning,
and combined seas could briefly reach or exceed 10 ft. 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

&&


.COASTAL FLOODING...King tides are predicted to continue this
weekend. High tides are forecast to be at 8.63 feet at the North
Spit tide gauge at around 11:44 AM local time. High tides
combined with surge and tidal anomaly will result in water levels
between 8.9 to 9.2 feet MLLW (Mean Lower Low Water). Minor
coastal flooding around Humboldt Bay, including King Salmon and
Jackson Ranch Road in the Arcata Bottoms, will be likely between
10 AM and 1 PM. A Coastal Flooding Advisory will be in effect
from 10 AM to 1 PM on Saturday. High tides are predicted to be at
8.24 feet at 12:35 PM on Sunday. At this point, coastal flooding
looks marginal for Sunday with high tides diminishing. -ZVS


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Coastal Flood Advisory from 10 AM this morning to 1 PM PST
     this afternoon for CAZ103.

NORTHWEST CALIFORNIA COASTAL WATERS...
     Coastal Flood Advisory from 10 AM this morning to 1 PM PST
     this afternoon for PZZ415.

&&

$$

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 061206 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 406 AM PST Sat Dec 6 2025 .UPDATE... Updated Aviation Section. && .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... A ridge of high pressure will strengthen and move further inland. This will allow temperatures to rise, at least in the mountains and desert. However, fog and stratus will persist over the Central Valley as well as the coastal ranges, lower Sierra foothills, and the Kern County mountains for at least the next few days. Dense fog will continue at times tonight into Saturday along major highways, such as Interstate 5 through the Grapevine in Kern County and Highway 152 through Pacheco Pass. It is also possible dense fog will occur anywhere that the stratus deck touches the lower Sierra foothills and Tehachapi Mountains, including at elevations around 1,500 to 2,500 feet. Otherwise, the Central Valley may fog back up anywhere the stratus deck clears. Currently, short term high resolution guidance shows a 40-50 percent chance of dense fog anywhere in the Central Valley and lower chances (about 20-30 percent) towards the foothills and coastal ranges through the late morning hours on Saturday. This dry and stable pattern will last until next week and beyond. The latest CPC outlooks have the Valley, the Sierra Nevada, and the Mojave Desert under a 70 to 90 percent chance of above average temperatures due to the persisting ridge. However, the outlooks show a shift from a 40 to 50 percent probability of below average precipitation to a 33 to 40 percent probability of above average precipitation for the much of the Valley and Sierra Nevada. && .AVIATION... IFR ceilings and visibilities are expected to prevail through 20Z Saturday before improving to MVFR. LIFR conditions will also persist in the coastal ranges, Sierra foothills, and the Kern County mountains due to the low stratus deck. && .AIR QUALITY ISSUES... On Saturday December 6 2025, Fireplace/Wood Stove Burning Status is: No Burning Unless Registered in Fresno, Kern, 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 medium. The level of certainty for days 3 through 7 is medium. Certainty levels include low...medium...and high. Please visit www.weather.gov/hnx/certainty.html for additional information and/or to provide feedback. && .HNX WATCHES/WARNINGS/ADVISORIES... Dense Fog Advisory until noon PST today for CAZ300-335. && $$ public/aviation....BSO/EW weather.gov/hanford
Office: LOX FXUS66 KLOX 061615 AFDLOX Area Forecast Discussion...UPDATED National Weather Service Los Angeles/Oxnard CA 815 AM PST Sat Dec 6 2025 .SYNOPSIS...05/441 PM. Light offshore winds will weaken through tonight. Benign weather will continue through the weekend with a low chance of morning coastal low clouds and fog. A significant warming trend will begin Sunday with temperatures well above normal Monday through next Friday, peaking Tuesday through Thursday. Offshore winds will increase Sunday and Monday and continue into much of the week. && .SHORT TERM (TDY-MON)...06/814 AM. ***UPDATE*** Pretty quiet weather this morning with clear skies and no marine layer present. Surface observations show a few gusty ridgetops across the Santa Lucia, Sierra Madre, and La Panza ranges (20 to 30 mph). Winds will increase some this afternoon and evening across these locations, but should remain below advisory levels. There is a low to moderate chance for a return of a very shallow marine layer along the coasts south of point conception tonight through Sunday morning (mainly Ventura & LA coast). Dense fog is possible. Confidence is low on coverage if occurs. Maximum Temps will warm a few to several degrees (esp. across coasts & valleys) through Monday. By Monday, most areas will be 8 to 12 degrees above normal. East-west offshore gradients will result in gusty sub-advisory winds across the Santa Lucia and La Panza ranges through Monday. ECMWF guidance suggests LAX-DAG gradients peak around -4 mb Monday afternoon. The Santa Susana mountains will likely have the best chance for a borderline wind advisory as guidance currently depicts. ***From Previous Discussion*** A Chamber of Commerce weekend is on tap for Srn CA. A ridge poking in from the west bringing hgts around 582 dam. Weak offshore flow should keep the low clouds away, but there is about a 10 percent chc that the LA south coast and SBA county west coast will see some morning low clouds and dense fog. There may be some local canyon winds in the morning, but nothing near advisory levels. Max temps will be the main talking point. Weaker offshore flow this morning will bring some cooling to the VTA/LA csts and vlys. But the rest of the area will see warming esp the Antelope Vly where the lack of cool air advection will bring 8 to 10 degrees of warming. On Sunday, sunny skies, higher than normal hgts and the offshore flow will all combine to bring 3 to 6 degrees of warming to the csts/vly S of Pt Conception and 1 to 2 degrees of warming elsewhere. Sunday's max temps will be 3 to 5 degrees above normal at the csts and 5 to 10 degrees inland. Stronger offshore flow will bring 20 to 25 mph canyon gusts to some areas in the morning. Hgts rise to 584 dam and this along with the better offshore flow will allow max temps to rise 3 to 6 degrees to the csts/vly S of Pt Conception and 1 to 2 elsewhere. This warming will bring some max temps up into the lower 80s in the warmest LA/VTA vly areas. Most areas away from the coast will end up 10 to 12 degrees above normal. .LONG TERM (TUE-FRI)...06/255 AM. The GFS has now trended towards the warmer EC solution and it seems pretty certain that all of next week will be a very warm one. Upper level high pressure will sit atop of the state and hgts will vary between 584 dam and 586 dam. These hgts are about 15 dam higher than the normal value of 571 dam. Offshore flow will continue through the period with a peak on Tuesday. Cannot rule out some morning low clouds in the LGB-LAX area on any given morning but right now it looks like the chance of this happening is under 50 percent. There will be some canyon winds but the only chance of advisory level gusts will be Tuesday morning and they will be more from the north than the NE. Max temps will be the name of the game for the entire week. Coastal temperatures will vary the most heating or cooling depending on the sfc gradient trends. The current thinking for coastal temps is for for a 3 to 5 degree rise on Tuesday bring max temps into the mid 70s to lower 80s (lower 70s right at the beaches). A degree or two of cooling each day Wed and Thu will bring the temps down into the upper 60s and 70s. Most coastal max temps S of Pt Conception will be 4 to 8 degrees above normal. The Central Coast will exceed that with temps coming 10 to 15 degrees over normal. The interior will see two days of warming Tue and Wed and then little change Thu and Fri. People can expect to see 80s in the vlys (with a 30 to 40 percent chc of some lower 90s). The lower elevations of the mtns and all of the far interior will have max temps in the 70s. These max temps are 12 to 18 locally 20 degrees above normal. Looking further ahead it appears that there will be some cooling next weekend but max temps will remain well above normal. && .AVIATION...06/1040Z. At 0910Z, there was no marine layer depth at KLAX, but there is a surface-based inversion up to around 2000 feet with a temperature around 17 degrees Celsius. VFR conditions are expected through at least 03Z Sunday, but there is a very low chance of VLIFR to LIFR conditions through 16Z at coastal terminals. After 03Z Sunday at coastal terminals, there is a low-to-moderate chance of VLIFR to LIFR conditions through 08Z Sunday increasing to a moderate chance of VLIFR to LIFR conditions after 08Z Sunday. KLAX...There is a less than 10 percent chance of VLIFR to LIFR conditions through 16Z, otherwise VFR conditions are expected. There is a 20 percent chance of VLIFR to LIFR conditions after 03Z Sunday increasing to a 30 percent chance after 08Z Sunday. Any east winds should remain less than 7 knots. KBUR...VFR conditions are expected through the period. No wind impacts are expected at this time. && .MARINE...06/717 AM. For the waters southwest through northwest of the Channel Islands beyond 10 NM offshore of the Central Coast, low-end Small Craft Advisory conditions expected at times through much of next week, especially across the north and western portions of PZZ670/673 during the afternoon and evening hours. Inside the southern California bight, high chance of winds and seas remaining below SCA levels through Monday night. Moderate chance of offshore winds from Ventura through Santa Monica through Tuesday afternoon. Guidance suggests winds and seas should remain below SCA levels thereafter through the work week. There is a moderate chance of dense fog over the coastal waters tonight through tomorrow. Likely south of Point Conception. Confidence remains low on timing and coverage. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...Beach Hazards Statement in effect until 11 AM PST this morning for zones 87-349-350-354-362-366. (See LAXCFWLOX). PZ...Small Craft Advisory in effect until 3 AM PST Monday for zones 670-673. (See LAXMWWLOX). && $$ PUBLIC...Rorke/Black AVIATION...Hall MARINE...Black SYNOPSIS...Lewis/CMC weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox FXUS66 KLOX 061645 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 845 AM PST Sat Dec 6 2025 .SYNOPSIS...05/441 PM. Light offshore winds will weaken through tonight. Benign weather will continue through the weekend with a low chance of morning coastal low clouds and fog. A significant warming trend will begin Sunday with temperatures well above normal Monday through next Friday, peaking Tuesday through Thursday. Offshore winds will increase Sunday and Monday and continue into much of the week. && .SHORT TERM (TDY-MON)...06/814 AM. ***UPDATE*** Pretty quiet weather this morning with clear skies and no marine layer present. Surface observations show a few gusty ridgetops across the Santa Lucia, Sierra Madre, and La Panza ranges (20 to 30 mph). Winds will increase some this afternoon and evening across these locations, but should remain below advisory levels. There is a low to moderate chance for a return of a very shallow marine layer along the coasts south of point conception tonight through Sunday morning (mainly Ventura & LA coast). Dense fog is possible. Confidence is low on coverage if occurs. Maximum Temps will warm a few to several degrees (esp. across coasts & valleys) through Monday. By Monday, most areas will be 8 to 12 degrees above normal. East-west offshore gradients will result in gusty sub-advisory winds across the Santa Lucia and La Panza ranges through Monday. ECMWF guidance suggests LAX-DAG gradients peak around -4 mb Monday afternoon. The Santa Susana mountains will likely have the best chance for a borderline wind advisory as guidance currently depicts. ***From Previous Discussion*** A Chamber of Commerce weekend is on tap for Srn CA. A ridge poking in from the west bringing hgts around 582 dam. Weak offshore flow should keep the low clouds away, but there is about a 10 percent chc that the LA south coast and SBA county west coast will see some morning low clouds and dense fog. There may be some local canyon winds in the morning, but nothing near advisory levels. Max temps will be the main talking point. Weaker offshore flow this morning will bring some cooling to the VTA/LA csts and vlys. But the rest of the area will see warming esp the Antelope Vly where the lack of cool air advection will bring 8 to 10 degrees of warming. On Sunday, sunny skies, higher than normal hgts and the offshore flow will all combine to bring 3 to 6 degrees of warming to the csts/vly S of Pt Conception and 1 to 2 degrees of warming elsewhere. Sunday's max temps will be 3 to 5 degrees above normal at the csts and 5 to 10 degrees inland. Stronger offshore flow will bring 20 to 25 mph canyon gusts to some areas in the morning. Hgts rise to 584 dam and this along with the better offshore flow will allow max temps to rise 3 to 6 degrees to the csts/vly S of Pt Conception and 1 to 2 elsewhere. This warming will bring some max temps up into the lower 80s in the warmest LA/VTA vly areas. Most areas away from the coast will end up 10 to 12 degrees above normal. .LONG TERM (TUE-FRI)...06/255 AM. The GFS has now trended towards the warmer EC solution and it seems pretty certain that all of next week will be a very warm one. Upper level high pressure will sit atop of the state and hgts will vary between 584 dam and 586 dam. These hgts are about 15 dam higher than the normal value of 571 dam. Offshore flow will continue through the period with a peak on Tuesday. Cannot rule out some morning low clouds in the LGB-LAX area on any given morning but right now it looks like the chance of this happening is under 50 percent. There will be some canyon winds but the only chance of advisory level gusts will be Tuesday morning and they will be more from the north than the NE. Max temps will be the name of the game for the entire week. Coastal temperatures will vary the most heating or cooling depending on the sfc gradient trends. The current thinking for coastal temps is for for a 3 to 5 degree rise on Tuesday bring max temps into the mid 70s to lower 80s (lower 70s right at the beaches). A degree or two of cooling each day Wed and Thu will bring the temps down into the upper 60s and 70s. Most coastal max temps S of Pt Conception will be 4 to 8 degrees above normal. The Central Coast will exceed that with temps coming 10 to 15 degrees over normal. The interior will see two days of warming Tue and Wed and then little change Thu and Fri. People can expect to see 80s in the vlys (with a 30 to 40 percent chc of some lower 90s). The lower elevations of the mtns and all of the far interior will have max temps in the 70s. These max temps are 12 to 18 locally 20 degrees above normal. Looking further ahead it appears that there will be some cooling next weekend but max temps will remain well above normal. && .AVIATION...06/1645Z. At 1630Z at KLAX, there was a surface-based inversion. The top of the inversion was 2400 feet with a temperature of 17 degrees Celsius. Overall, moderate to high confidence in 18Z TAF package. Through this evening, high confidence in CAVU conditions for all sites. For late tonight/Sunday morning, there is a 30% chance of CIG/VSBY restrictions at KSMO, KLAX and KLGB. KLAX...Overall, moderate to high confidence in 18Z TAF. Through this evening, high confidence in CAVU conditions. From 10Z-17Z, there is a 30% chance of LIFR/VLIFR conditions. No significant easterly wind component is expected. KBUR...High confidence in 18Z TAF as CAVU conditions are expected through the period. && .MARINE...06/717 AM. For the waters southwest through northwest of the Channel Islands beyond 10 NM offshore of the Central Coast, low-end Small Craft Advisory conditions expected at times through much of next week, especially across the north and western portions of PZZ670/673 during the afternoon and evening hours. Inside the southern California bight, high chance of winds and seas remaining below SCA levels through Monday night. Moderate chance of offshore winds from Ventura through Santa Monica through Tuesday afternoon. Guidance suggests winds and seas should remain below SCA levels thereafter through the work week. There is a moderate chance of dense fog over the coastal waters tonight through tomorrow. Likely south of Point Conception. Confidence remains low on timing and coverage. AVDAFDLOX && .LOX WATCHES/WARNINGS/ADVISORIES... CA...Beach Hazards Statement in effect until 11 AM PST this morning for zones 87-349-350-354-362-366. (See LAXCFWLOX). PZ...Small Craft Advisory in effect until 3 AM PST Monday for zones 670-673. (See LAXMWWLOX). && $$ PUBLIC...Rorke/Black AVIATION...RAT MARINE...Black SYNOPSIS...Lewis/CMC weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox
Office: STO FXUS66 KSTO 052117 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 117 PM PST Fri Dec 5 2025 .KEY MESSAGES... - Periods of clouds, mist, or fog continue in the Central Valley for the next few mornings - Seasonable temperatures and light winds are forecast over the next several days - Tonight - Early Sat. AM's rain chances for Shasta County have lowered with only a 10-30% of measurable rain. && .DISCUSSION... ...Today... Current GOES-West visible satellite imagery illustrates the blanket of stratus in the Central Valley gradually eroding, with some high clouds passing overhead from the north. Visibilities have improved across the Central Valley this afternoon, but still see swaths of low clouds/stratus clouds over the Valley. We can expect another round of patchy dense fog and low clouds once again tonight into Saturday morning with best chances from Marysville southward again. Dry weather and seasonable temperatures are forecasted for the region, with 50s to 60s 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. ...Tonight-Sunday... A weak system passing to the north over the weekend may bring some isolated, light showers to the Shasta County mountains, however little to no impacts or accumulations are expected. Elsewhere, dry conditions will persist over the weekend with daily chances for fog, mist and low clouds especially in the Valley. High temperatures are forecast to be in the 40s to 60s across interior NorCal. ...Next Week... High pressure builds across the region next week, allowing for a gradual warming trend with high temperatures warming to the 50s to near 70 (mainly for areas outside of stratus/fog development). Dry conditions will continue through next week. Some ensembles are indicating a pattern change in mid December but there is a large amount of uncertainty as it is too far out in time. && .AVIATION... Lingering low cigs and mist across the Central Valley this afternoon and evening, although some sites may briefly return to VFR conditions. Another round of BF/FG and low stratus returns tonight after 03Z-12Z Saturday, with areas of MVFR/IFR conditions, locally IFR, particularly from Sacramento southward. Light and variable surface winds less than 12kts. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$
Office: SGX FXUS66 KSGX 061645 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 845 AM PST Sat Dec 6 2025 .SYNOPSIS... Warmer this weekend with the potential for patchy dense fog near the coast tonight and again Sunday night. Much warmer next week with highs 10-15 degrees above normal and periods of weak to locally moderate Santa Ana winds, strongest on Tuesday. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .Morning Update... Satellite is showing cloud free skies across Southern California. Temperatures this morning are starting out in the lower 40s in the wind sheltered valleys and locally in drainage basins. Coastal areas and foothills above the inversion are experiencing a milder start in the 50s. Temperatures remain on pace to reach into the lower 70s for much of the coastal basin for a few hours this afternoon. Coastal fog development tonight remains uncertain and patchy at best. No changes currently to the forecast. Previous discussion (2:20 AM Saturday)... Skies remain clear this morning with light winds across the region. Pressure gradients will be nearly neutral to the local deserts through Sunday morning, allowing for a weak sea breeze to develop this afternoon. With the return of this weak onshore flow and a forecasted weak coastal eddy tonight, we could see a development of dense fog over the coastal waters and locally into the coastal areas tonight into Sunday morning. Weak offshore flow kicks back in on Sunday morning, helping to clear out any fog. Patchy dense fog may briefly return again Sunday evening before slightly stronger offshore flow develops Sunday night. Aside from that, there will be gradual warming through the weekend as an upper level ridge of high pressure begins to build in from the west. High temperatures today will be around 3-7 degrees above normal, increasing to around 5-10 degrees above normal for Sunday. Next week can be summed up with warm and dry. The upper high slowly shifts east through the week, directly overhead by Friday. At the surface, mostly weak Santa Ana winds will prevail, becoming locally moderate on Tuesday morning as surface gradients peak. With no upper level support, winds will remain confined to the usual passes, canyons, and coastal slopes and follow a diurnal pattern, strongest in the mornings and then weakening during the afternoon. On Tuesday morning, northeast to east gusts in the wind prone locations will generally peak around 30-45 mph. Monday and Wednesday through Friday will see peak gusts closer to 20-35 mph. Only minor daily fluctuations in temperatures is expected, with highs generally 10-15 degrees above normal each day Monday through Saturday. Dry air and weak winds overnight will allow for decent cooling, so HeatRisk remains low. For the valleys and deserts it will very much be a winter in the morning, summer (highs in the low 80s) for a few hours in the early afternoon, and fall in the evening sort of pattern. The forecast becomes a little more uncertain towards next weekend with the upper high potentially beginning to weaken or break down, influencing how much cooling we'll see and whether or not onshore flow will return. Still no signs of precipitation around here until the second half of the month. && .AVIATION... 061630Z....Low clouds/fog have the potential to develop along the immediate coast after 03Z Sun. Chances are 10-20% in San Diego County through 12Z Sun and 30-40% in Orange County through 19Z. Areal coverage of any low clouds/fog will be patchy with bases less than 500 ft and visibility 1 mile or less. Confidence is not high enough in VIS restrictions to include fog in the TAFs at coastal sites at this time. VFR conditions will prevail for inland areas through the TAF period. && .MARINE... No hazardous marine conditions are expected through Thursday. && .BEACHES... Morning high tide is predicted to be 6.5 to 7 ft on Sunday at 10 AM in La Jolla and at 9:50 AM in Newport Beach. 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...Westerink AVIATION/MARINE/BEACHES...CO
Office: MTR FXUS66 KMTR 061741 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 941 AM PST Sat Dec 6 2025 ...New AVIATION... .KEY MESSAGES... Updated at 250 AM PST Sat Dec 6 2025 - Persistent forecast through the next seven days with benign conditions and no precipitation expected - Impacts from Tule Fog in the North Bay and interior East Bay valleys - Next chance for rain towards the middle of the month && .UPDATE... Issued at 845 AM PST Sat Dec 6 2025 Satellite imagery shows the stratus deck extensively covering the Bay Area valleys, extending a little bit into the corridor between northern Monterey County and the San Juan Bautista area, while most of the Monterey Bay region and the interior Central Coast remain clear. The loop shows a couple of interesting eddy patterns over the San Francisco Bay which will make come of the short-term stratus development a little harder to predict, but the overall trend should be a slow and gradual mixing out through the morning and afternoon hours. The main forecast question will be how fast the stratus mixes out over the North and East Bay valleys, as the cooler temperatures across both regions are dependent on the stratus lingering over the region. DialH && .SHORT TERM... Issued at 250 AM PST Sat Dec 6 2025 (Today and tonight) Satellite imagery overnight reveals a different scenario than the last few nights. Tule Fog remains persistent across the Central Valley, West Delta, and far East Bay Valleys. The change is a redevelopment of the marine layer as high pressure builds overhead. There is stratus along portions of the coastal waters and Bay Area with the Central Coast remaining cloud free. There was a Cold Weather Advisory in effect for portions of the North Bay, but an influx of low level moisture/stratus limited widespread temps below 36 degrees. In fact, a few places saw an increase in temperatures once the stratus developed. Therefore, cancelled the advisory. Another interesting note are the temp spreads across the N Bay from valley to mts with upper 30s coldest in the valleys and low 50s highest peaks. The warmer temps are likely being enhanced by NE winds above the stratus deck. One weather impact that hasn't changed is patchy dense fog impacting the N Bay and E Bay Valleys. It's patchy and not widespread enough to warrant a dense fog advisory as of this writing. Rest of today and tonight: clouds across the Bay Area will be slow to clear through late morning. A cool and damp start to the day in those locations. Outside of the stratus, temperatures are colder, but not as cold as yesterday. Slightly warmer temps likely due to some weak offshore flow as well. For this afternoon expect a few clouds passing overhead as a weak front to the north washes out against the ridge of high pressure. Given lingering stratus and Tule fog went on colder side of guidance for Max Temps in the N and E Bay with Upper 50s to 60s. Elsewhere, generally 60s to a few near 70. For tonight the ridge overhead strengthens a little. This will help to compress the marine layer. In the big picture, not a lot of change expected in overall sensible weather with clouds and fog impacting N and E Bay and some of the Bay Area. && .LONG TERM... Issued at 330 AM PST Sat Dec 6 2025 (Sunday through Friday) Solid agreement with model guidance through at least Friday as high pressure dominates CA. A gradual warming trend is expected with peak warmth Wed-Fri as temperatures soar above normal with interior highs reaching the upper 60s to mid 70s. The challenge next week will be N and E Bay temps and potential Tule fog impacts keeping temperatures colder. There continues to be a few weak systems passing well to the north, which may lead to some drizzle over the coastal waters but land areas remain dry. Friday and beyond - We'll continue to monitor a lowered end chance for a pattern change. Cluster analysis has a few clusters breaking down the ridge. However, operational ensemble guidance keep the ridge locked in or flattens it with zonal flow. We'll see how this changes over the coming days. && .AVIATION... (18Z TAFS) Issued at 940 AM PST Sat Dec 6 2025 LIFR to IFR conditions across much of the Bay Area this morning, while VFR conditions prevail at the Monterey Bay terminals. Low ceilings and/or visibilities are forecast to improve by around 20Z and give way to mostly VFR conditions. Onshore winds increase by mid- to-late afternoon across the San Francisco Bay and Monterey Bay terminals. High confidence for low ceilings and/or visibilities for the North Bay and East Bay with moderate confidence for the Bay Area terminals late tonight through Sunday morning. Moderate to high confidence for VFR conditions to prevail through much of that TAF period for the Monterey Bay terminals. Low clouds and/or fog look to improve by midday Sunday. Vicinity of SFO...IFR conditions across much of the region this morning. Conditions are forecast to improve by 19Z-20Z and give way to VFR throughout the remainder of the afternoon. Moderate confidence for IFR conditions to return either late tonight or early Sunday morning as wind speeds turn more offshore. Onshore winds are forecast by Sunday afternoon with VFR conditions. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...VFR through the TAF period. Light to southerly winds prevail this morning and are forecast to become onshore by early-to-mid afternoon. Winds diminish overnight and become southerly early Sunday morning. && .MARINE... (Today through Thursday) Issued at 845 AM PST Sat Dec 6 2025 Fresh northwesterly winds persist through this weekend and into the middle of next week. Strong to near gale force gusts will be possible through this weekend. 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 Sunday for CAZ006-506-508- 529-530. PZ...Small Craft Advisory until 3 AM PST Sunday for Pt Pinos to Pt Piedras Blancas 0-10 nm. Small Craft Advisory until 9 AM PST Sunday for Pigeon Pt to Pt Pinos 10-60 NM. && $$ SHORT TERM...MM LONG TERM....MM 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