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Office: EKA
FXUS66 KEKA 090704
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
1204 AM PDT Wed Jul 9 2025

.SYNOPSIS...Near or slightly below normal temperatures are
expected again Wednesday. Warming is expected again Thursday with
additional warming Friday and hot weather continuing into early
next week.


&&

.DISCUSSION...The center of the upper low currently moves over the
area. This has the potential to bring some thunderstorms to the
area. The models aren't explicitly outputting thunderstorms, but
there is some elevated instability. This, combined with the dynamics
of the low and steep lapse rates aloft may bring some nocturnal
thunderstorms.

Wednesday during the day the upper level low is expected to move off
to the east and we will be in northwest flow. It looks like the
threat for thunderstorms will diminish through the day light hours
on Wednesday.

Wednesday night into Thursday morning offshore flow is expected in
Humboldt and Del Norte counties. This should diminish the marine
layer and allow skies to clear. Thursday is expected to be the
transition day with warmer temperatures, but highs are expected to
remain in the 90s in most inland areas with low to mid 60s possible
along the coast. Friday additional warming is expected with highs
climbing over 100 in many of the valleys. The coast may see highs in
the middle to upper 60s with continued offshore flow. This is
expected to bring moderate to major heat risk to many of the areas.
This heat is expected to persist through the weekend in some of the
interior areas. A heat advisory may be needed in some of the more
persistently hot areas. There is some uncertainty on how much the
valleys will cool off at night and that could mitigate the impact of
the heat. MKK


&&

.AVIATION...Mostly IFR conditions are expected along the North Coast
into Wednesday morning. The upper low spinning over head has
aided in the deepening of the marine layer, as well. With
southerly flow up the Russian River Valley, there is a possibility
of MVFR ceilings for KUKI a few hours before sunrise Wednesday.
There appears to be little chance for clearing through the day
Wednesday for coastal terminals with ceilings most likely lifting
into MVFR range by the afternoon. /JLW


&&

.MARINE...Light winds and low seas are currently dominating the
marine environment as an upper low spins over the coastal waters.
This low will move inland Wednesday allowing surface high pressure
to re-build toward the Northwest California coast over the Eastern
Pacific. This will enhance the pressure gradient and once again
strengthen the northerlies. Near gale to gale wind gusts are
possible Thursday through Saturday, most likely over the outer water
zones, pulling into just the northern waters this weekend as the
thermal trough builds north over land. Steep short period seas will
build in response to the gale northerlies. /RPA


&&

.FIRE WEATHER...High temperatures in the 80's and 90's are expected
for most of the interior on Wednesday. The marine layer is expected
to remain deeper through Wednesday morning as an upper-low moves
past the area, bringing slightly higher afternoon RHs. As this upper
low moves overhead there is the potential for thunderstorms to move
across Humboldt, Del Norte and Trinity counties early Wednesday, yet
as of writing this no storms have been seen via satellite/radar.
Confidence on these storms manifesting remains low and the better
chance for Thunderstorms remains to the north of the area, with
storms seen over NE Oregon. Overnight recoveries generally remain
good aside from the exposed ridges in the thermal belt.

Much hotter temperatures and drier humidity are likely in the
interior late this week. Thursday and Friday mornings offshore flow
will bring poor recoveries to the higher elevations and may push the
stratus off the coast. Triple digit temperatures are likely in most
of the interior valleys by Friday with very low afternoon RHs and
moderate overnight recoveries. JB


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory from 3 AM to 11 AM PDT Thursday for
     PZZ455-470.

     Gale Watch from Thursday morning through Thursday evening
     for PZZ455-470-475.

     Small Craft Advisory from 9 PM this evening to 11 AM PDT
     Thursday 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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see the forecast zone map online:
https://www.weather.gov/images/eka/zonemap.png



Office: HNX FXUS66 KHNX 090458 AFDHNX Area Forecast Discussion National Weather Service Hanford CA 958 PM PDT Tue Jul 8 2025 .UPDATE... Updated Aviation Section. && .KEY MESSAGES... 1. Temperatures near season averages across the region today before a gradual warm up into the triple digits later this week. 2. Low RH values 15 to 25 percent will stretch across much of the San Joaquin Valley and Sierra Nevada with values 5 to 10 percent in the Mojave Desert. RH will decrease over the region later in the week with warming temperatures. && .DISCUSSION... High pressure ridge pattern becoming the dominate feature over the West Coast during the latter half the week. With this, will expect a continuation of the warming trend as widespread triple digits will be seen by Thursday and Friday. In addition to the rise in temperatures, the ridge pattern will allow for monsoonal moisture to surge northward as a potential for convection will exist across the Mojave Desert later this week. With little change in the overall pattern, will expect the duration of the heat wave to last from near Friday through at least next Tuesday. Ensemble Probability of Exceedance (PoE) of reaching 100 degrees starts off below 30% over the next few days. Thursday marks the transition period at which time the PoE jumps up to a range between 50% and 90%, with the higher end on the west side of the San Joaquin Valley along the Interstate-5 corridor. Also, by Thursday, the Kern Desert max’s out its PoE with values above 90% for the duration of the period. Friday shows both the San Joaquin Valley and Kern Desert having probabilities in the 90% and above range. At that point, confidence in widespread triple digits increases for the start of the next heat wave. Little change in PoE values observed through the weekend as triple digits will be here to stay through the early part of next week. Ensemble Cluster analysis of Precipitable-Water is showing good consensus in attempting to push monsoonal moisture northward toward Central California later this week. While the southwesterly flow aloft will hinder its surge toward Central California. Yet, ensemble analysis does show a very slight chance of development toward Friday and Saturday across the Kern Desert. Otherwise, dry and hot across Central California with afternoon wind breezes over the favored locations. && .AVIATION... 06Z Update: VFR conditions will prevail for the next 24 hours across the Central California Interior. && .AIR QUALITY ISSUES... None. && .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... None. && $$ Public/Aviation....Molina/EW weather.gov/hanford weather.gov/hanford
Office: LOX FXUS66 KLOX 091114 AFDLOX Area Forecast Discussion National Weather Service Los Angeles/Oxnard CA 414 AM PDT Wed Jul 9 2025 .SYNOPSIS...09/300 AM. A warming trend affecting Southwest California will peak Today and Thursday, with many areas 5 to 10 degrees above normal. Temperatures will return to near normal over the weekend. && .SHORT TERM (TDY-FRI)...09/259 AM. High confidence in a significant warm up into today with similarly hot temperatures and moderate heat risk focused away from the coast into Thursday. The warm up is attributed to a rapidly building ridge from the east through today and offshore trends from the north during this period as well. Coastal areas will likely see highs around 70 degrees, with interior coastal areas like Los Angeles reaching near 90 degrees. Warmer valleys will experience highs between 95 and 105 degrees. Heat Advisories are unlikely due the relatively short duration of the heat as well as relatively cool overnight temperatures providing some relief. Night to morning clouds will likely continue near the coast each day with the potential for dense fog this and Thursday morning in particular. Monsoon moisture could limit low cloud development in Los Angeles and Ventura Counties, leading to mostly clear skies with only mid to high clouds today and Thursday. There is a small (5 percent) chance of a shower or two in the higher mountains of Ventura and Los Angeles Counties this afternoon to early evening. Breezy northwest to onshore winds will continue through Thursday with advisory level Sundowners becoming likely (60 percent chance) for southwest Santa Barbara County this and Thursday evening. The ridge breaks down and supports a strong onshore push into Friday, bringing relief from the heat, but with increased fire weather concerns with winds locally approaching advisory levels for the interior mountains and deserts. Low clouds may push back into lower valleys by Friday morning if a moderate eddy forms in the wake of the Sundowners. .LONG TERM (SAT-TUE)...09/259 AM. The cool down will continue into Saturday with reduced heat risk across the region. There is a 30 percent chance of the ridge rebuilding early next week with another round of moderate heat risk (widespread highs in the 90s and 100s away from the coast). The ridge may wobble into a favorable position for monsoonal showers or thunderstorms at times next week, but low confidence on when and if this will happen. Gusty onshore winds may approach advisory levels for prone inland areas such as typical mountain corridors and Antelope Valley foothills through the weekend with elevated fire weather conditions continuing away from the coast with the potential for rapid fire growth with any new fire starts. && .AVIATION...09/1113Z. At 08Z, the marine layer was 500 feet deep at KLAX. The top of the inversion was near 2100 feet with a max temperature of 27 C. High confidence in KPMD, KWJF, KBUR, and KVNY. Moderate confidence in all other TAFs. There is a 10-20% chance of LIFR-IFR cigs developing at KLAX, KSMO, KLGB, KOXR, KCMA, and KSBA from 13Z-16Z and again after 08Z. For KSBP and KSMX dense fog and VSBY as low as 1/4SM will be possible from 10Z-17Z and again after 05Z. KLAX...Moderate confidence in TAF. There is a 10-20% chance of OVC003-OVC006 cigs from 13-16Z and again after 08Z. No significant east winds expected. KBUR...High confidence in TAF. && .MARINE...09/228 AM. Small Craft Advisory (SCA) level winds will continue across the outer waters south of Point Conception, spreading to the northern waters by this afternoon, and lasting through at least late Thursday night. Localized Gale Force winds are possible (30% chance) this evening across the outer waters and near Point Conception and Santa Cruz Island. SCA level winds are likely for the inner waters north of Point Sal and the Santa Barbara Channel each afternoon/evening today and Thursday. Local SCA winds may occur this evening off the coast of LA and Orange Counties, particularly across the San Pedro Channel and near Point Mugu. Steep and choppy seas are likely this afternoon through at least Thursday night. Patchy dense fog may affect the coastal waters overnight and in the morning hours, with best chances in the waters off the Central Coast through Thursday morning. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...Wind Advisory in effect from 3 PM this afternoon to 3 AM PDT Thursday for zones 349-351. (See LAXNPWLOX). PZ...Small Craft Advisory in effect from noon today to 9 PM PDT this evening for zone 645. (See LAXMWWLOX). Small Craft Advisory in effect from 3 PM this afternoon to 9 PM PDT this evening for zone 650. (See LAXMWWLOX). Small Craft Advisory in effect from noon today to 3 AM PDT Friday for zone 670. (See LAXMWWLOX). Small Craft Advisory in effect until 3 AM PDT Friday for zones 673-676. (See LAXMWWLOX). && $$ PUBLIC...Munroe AVIATION...Munroe/Schoenfeld MARINE...Schoenfeld SYNOPSIS...MW/CC weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox
Office: STO FXUS66 KSTO 082023 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 123 PM PDT Tue Jul 8 2025 .DISCUSSION... .SYNOPSIS... Mostly dry with near seasonable high temperatures today in the Valley. Widespread moderate HeatRisk is anticipated across the Valley starting Thursday, and portions of the northern Sacramento Valley will hit triple-digit highs through the weekend. Breezy winds combined with low humidity will lead to areas of elevated fire weather concerns in Shasta County through the weekend. && .KEY MESSAGES... * Today-Thursday: - Smoke from the Green wildfire visible on satellite, southerly winds continuing to move the plume north of Redding this afternoon - Offshore low is continues to promote periods of breezy southerly winds across the area today. - Continued dry and mostly clear weather today, with a warming trend starting on Wednesday as high pressure begins to build in the Desert SW/Four Corners region. - On Thursday, trough exits the area, ridge continues to build in the Desert SW, promotes a period of breezy northerly winds. - Highest gusts around 15-25 mph in the typically wind-prone areas of the Valley - Areas of elevated fire weather concerns in Shasta County into the weekend, due to low humidities and periods of breezy winds * Friday-Monday: - Continued warming, with widespread Moderate HeatRisk in the forecast for interior NorCal. Triple-digit highs in the northern and central Sacramento Valley and northern San Joaquin Valley Thursday - Sunday. - Upper level ridging looks to continue dominating our pattern into next week .Changes from previous forecast... - No significant changes to the forecast && .AVIATION... VFR conditions across interior NorCal next 24 hours. Periods of breezy onshore winds with gusts up to 15-20 knots in the Delta vicinity through 12z Wednesday, then gusts up to 15 kts. Breezy southerly/southwesterly wind gusts in the Sacramento Valley and northwesterly wind gusts in the northern San Joaquin Valley up to 15-20 kts until 06z Wednesday. Local MVFR conditions possible at times in HZ/FU vicinity of Shasta County wildfire, including KRDD. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$
Office: SGX FXUS66 KSGX 090948 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 248 AM PDT Wed Jul 9 2025 .SYNOPSIS... The heat for inland areas will peak today and Thursday with high temperatures 5 to 10 degrees above average. Not quite as hot for Friday into next week with the coast and valleys near to around 5 degrees below average with the deserts around 5 degrees above average. Patchy coastal low clouds for this morning will increase in coverage by the weekend and spread into the western valleys late each night. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .SHORT TERM (Today through Friday)... High temperatures will warm a few more degrees today with not much change for Thursday. High temperatures for today and Thursday will be a few degrees above average near the coast to 5 to 10 degrees above average for inland areas. High temperatures will range from the 70s near the coast to the 90s to 105 for the Inland Empire with 114 to 118 for the lower deserts. For Friday, high temperatures will be 4 to 8 degrees cooler than Thursday for the coast and valleys with the deserts a few degrees cooler. Friday high temperatures will range from the lower to mid 70s near the coast to the upper 80s to upper 90s for the Inland Empire with 110 to 114 for the lower deserts. The marine layer will be around 1500 feet deep into Thursday with patchy coverage of low clouds for early this morning increasing in coverage for late tonight into Thursday morning and for late Thursday night into Friday with the low clouds returning to portions of the western valleys. There will also be a few mid and high clouds today from thunderstorms well to the south across central Baja. && .LONG TERM (Saturday through Tuesday)... Not much change from Friday with high temperatures for the coast and valleys a few to around 5 degrees below average with the deserts around 5 degrees above average. Night and morning coastal low clouds will spread into the western valleys late each night. && .AVIATION... 090900Z....Coast...FEW-SCT high clouds above 15000 feet MSL. Patchy low clouds based 700-1000 feet MSL currently offshore may develop onshore, mainly at the coast of southern SD County between 11-15z. 60% for brief cigs at KSAN, 35% for KSNA and 20% for KCRQ. Scatter out of any cigs by 16Z. Slightly more extensive low clouds with similar bases to develop at the coast after 08Z Thu. Valleys/Mountains/Deserts...VFR conditions with FEW-SCT thin high clouds above 15000 feet MSL through early Thu. && .MARINE... Northwest wind gusts around 20 kts near San Clemente Island Wednesday afternoon and evening. Otherwise, no hazardous marine weather is expected through Sunday. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...Heat Advisory from 10 AM this morning to 8 PM PDT Thursday for Riverside County Mountains-San Bernardino and Riverside County Valleys-The Inland Empire-San Diego County Mountains- San Diego County Valleys. Extreme Heat Warning from 10 AM this morning to 8 PM PDT Thursday for Coachella Valley-San Diego County Deserts-San Gorgonio Pass near Banning. PZ...None. && $$ PUBLIC...17 AVIATION/MARINE...Westerink
Office: MTR FXUS66 KMTR 091130 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 430 AM PDT Wed Jul 9 2025 ...New AVIATION, MARINE... .KEY MESSAGES... Updated at 101 AM PDT Wed Jul 9 2025 - Warming trend begins today through the weekend, with patchy Moderate HeatRisk across the Bay Area and Central Coast Thursday and Friday. - Localized elevated fire weather threat starting today through the weekend across the higher elevations. && .SHORT TERM... Issued at 101 AM PDT Wed Jul 9 2025 (Today and tonight) Satellite imagery shows widespread marine layer stratus across the valleys of the Bay Area and Central Coast, as data from the Fort Ord profiler shows the top of the marine layer becoming more diffuse while rising to at least 3000 feet over the last evening. Low temperatures this morning will hover in the lower to middle 50s in the lower elevations, and as high as the lower 60s in the highest peaks. Today marks a pattern change from the cooler regime of the last few days to a warming pattern that (spoiler alert) looks to set up for the rest of the week. The upper level low that brought us the robust marine layer and the cool temperatures is dissipating while it meanders towards landfall in the North Coast. This will allow an ridge that's set up over the desert Southwest to edge into the state while a synoptic high pressure system develops in the east Pacific, causing temperatures to warm. Temperatures will range from the upper 70s to the middle 80s inland, with the warmest spots in southern Monterey and San Benito Counties reaching the upper 90s, while locations on the Bays reach highs in the upper 60s and the 70s. The marine layer will compress, but the coastal areas should remain rather cool with highs in the upper 50s to the lower 60s. Some elevated fire weather threat is forecast to develop today across areas above and inland of the marine layer's influence. The combination of dry daytime humidities of around 15-30% and localized gusts to 30 mp will be the main factors behind the elevated threat. However, the winds will remain onshore, leading to the fire weather threat being diurnally driven, especially in the foothills where lighter winds and good overnight recoveries are expected each night. && .LONG TERM... Issued at 101 AM PDT Wed Jul 9 2025 (Thursday through Tuesday) Temperatures continue to rise on Thursday and Friday as the high pressure systems become more established, with the inland valleys seeing highs in the middle 80s to middle 90s on both days, while the warmest interior locations see temperatures rising up to a few degrees above 100. Patches of Moderate HeatRisk are expected on Thursday and Friday across the interior North Bay, East Bay, and South Bay, in addition to the Santa Lucia mountains and the southern tip of San Benito County. Remember to take frequent cooling breaks and drink plenty of water if participating in outdoor activities on both days. As a very weak upper level disturbance passes through the state this weekend, temperatures will cool slightly to the lower 80s to lower 90s in the interior Bay Area with an shortwave trough coming through the West Coast, while the interior Central Coast remains rather warm with temperatures in the 90s. The pattern will otherwise remain rather stable through the early part of next week, with warm inland temperatures, cool coastal temperatures, light onshore winds, and localized elevated fire weather threat in the interior developing each afternoon. && .AVIATION... (12Z TAFS) Issued at 419 AM PDT Wed Jul 9 2025 MVFR to LIFR ceilings early this morning with a robust marine layer in place. Conditions will persist through most of the morning into the early afternoon for some spots. Expect some breezy periods of onshore flow this afternoon with a return of low stratus ceilings around sunset for most, after midnight for the North Bay locations. Vicinity of SFO...MVFR/IFR stratus ceilings will persist through the late morning, clear out for much of the afternoon and early evening, then returning around sunset with a 2500' marine layer in place. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...IFR/LIFR persisting through most of the morning with clearing expected around noon. HiRes guidance is anticipating a later clearing this morning than yesterday and earlier return this evening with the marine layer topping out at 2500'. Onshore flow may breezy at times this afternoon. && .MARINE... (Today through Monday) Issued at 419 AM PDT Wed Jul 9 2025 Winds will begin to increase out of the north this afternoon and continue to strengthen through Wednesday night becoming fresh to strong for Thursday into the weekend. Rough to very rough significant wave heights will also persist into the weekend for the outer waters. && .MTR WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...Small Craft Advisory from 3 PM this afternoon to 3 AM PDT Thursday for Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm. Small Craft Advisory from 3 PM this afternoon to 3 PM PDT Thursday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM. && $$ SHORT TERM...DialH LONG TERM....DialH AVIATION...JM MARINE...JM 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