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FXUS66 KMTR [Monterey CA] 281744 AFDMTR ∨

FXUS66 KMTR 281744
AFDMTR [HEAD]

National Weather Service San Francisco California 10:44am PDT Fri Mar 28 2025 ∨

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
1044 AM PDT FRI MAR 28 2025 [HEAD]

New aviation, marine. ∨

...NEW AVIATION, MARINE... [DISC]

Synopsis. Issued at 3:03am PDT Friday Mar 28 2025 ∨

.SYNOPSIS...
ISSUED AT 303 AM PDT FRI MAR 28 2025 [DISC]

Cool conditions and hazardous beach conditions continue today. A brief dry period Saturday precedes several rounds of rain and wind slated for next week. ∨

COOL CONDITIONS AND HAZARDOUS BEACH CONDITIONS CONTINUE TODAY. A
BRIEF DRY PERIOD SATURDAY PRECEDES SEVERAL ROUNDS OF RAIN AND
WIND SLATED FOR NEXT WEEK. [DISC]

Short term. (today and tonight) issued at 3:03am PDT Friday Mar 28 2025 ∨

.SHORT TERM...
(TODAY AND TONIGHT)
ISSUED AT 303 AM PDT FRI MAR 28 2025 [DISC]

Rain shower activity from a surface trough with upper level support will continue to diminish through the morning. Rainfall accumulation will be beneficial with locally higher totals along the coast and in the higher terrain due to orographic lift - the primary impact expected is wet roadways. Aside from that, expect temperatures to remain below seasonal averages and clouds to lift and decrease in coverage throughout the day as the upper-level shortwave trough ejects east. While cold conditions are not anticipated to be widespread enough for a Frost Advisory tonight, isolated portions of the higher terrain in the North Bay interior mountains, eastern Santa Clara Hills, and interior Monterey and San Benito Counties are forecast to be in the 32–36° range. As always, please protect people, pets, plants, and pipes. Last but certainly not least, a High Surf Advisory remains in effect until 11pm tonight for all Pacific coast beaches (sans northern Monterey Bay as the area has a beach hazards statement in effect until 11pm tonight). If you're planning on being near the Pacific Ocean, keep pets on a leash, stay off of jetties and rocks, wear a life Jacket, and never turn your back on the ocean! ∨

RAIN SHOWER ACTIVITY FROM A SURFACE TROUGH WITH UPPER LEVEL
SUPPORT WILL CONTINUE TO DIMINISH THROUGH THE MORNING. RAINFALL
ACCUMULATION WILL BE BENEFICIAL WITH LOCALLY
HIGHER TOTALS ALONG THE COAST AND IN THE HIGHER TERRAIN DUE TO
OROGRAPHIC LIFT - THE PRIMARY IMPACT EXPECTED IS WET ROADWAYS. ASIDE
FROM THAT, EXPECT TEMPERATURES TO REMAIN BELOW SEASONAL AVERAGES AND
CLOUDS TO LIFT AND DECREASE IN COVERAGE THROUGHOUT THE DAY AS THE
UPPER-LEVEL SHORTWAVE TROUGH EJECTS EAST. WHILE COLD CONDITIONS
ARE NOT ANTICIPATED TO BE WIDESPREAD ENOUGH FOR A FROST ADVISORY
TONIGHT, ISOLATED PORTIONS OF THE HIGHER TERRAIN IN THE NORTH BAY
INTERIOR MOUNTAINS, EASTERN SANTA CLARA HILLS, AND INTERIOR
MONTEREY AND SAN BENITO COUNTIES ARE FORECAST TO BE IN THE 32 TO
36 DEGREE RANGE. AS ALWAYS, PLEASE PROTECT PEOPLE, PETS, PLANTS,
AND PIPES. LAST BUT CERTAINLY NOT LEAST, A HIGH SURF ADVISORY
REMAINS IN EFFECT UNTIL 11 PM TONIGHT FOR ALL PACIFIC COAST
BEACHES (SANS NORTHERN MONTEREY BAY AS THE AREA HAS A BEACH
HAZARDS STATEMENT IN EFFECT UNTIL 11 PM TONIGHT). IF YOU`RE
PLANNING ON BEING NEAR THE PACIFIC OCEAN, KEEP PETS ON A LEASH,
STAY OFF OF JETTIES AND ROCKS, WEAR A LIFE JACKET, AND NEVER TURN
YOUR BACK ON THE OCEAN! [DISC]

Long term. (Saturday through Thursday) issued at 3:03am PDT Friday Mar 28 2025 ∨

.LONG TERM...
(SATURDAY THROUGH THURSDAY)
ISSUED AT 303 AM PDT FRI MAR 28 2025 [DISC]

Blink and you might miss the shortwave ridge tomorrow. While the thermometer may read the same temperature today as it will tomorrow, the lighter winds tomorrow will have the sensible weather feeling warmer. Probably of more interest, tomorrow will be the driest day of the next seven days. While not dry for quite a 24-hour period, the first 75% of the day or so will be dry before a triple-point low starts knocking on the doorstep. Sunday's rainfall is expected to take place within the warm sector, so steady, light, stratiform rain is expected with a gradual northwest to southeast gradient of 0.50" in the North Bay mountains to 0.01" in the interior Central Coast respectively. Monday's rainfall will be in the form of a cold front so rainfall intensity can be expected to be relatively heavier over a shorter period of time as compared to Sunday with a similar (Albeit sharper) northwest to southeast gradient of 0.75" in the North Bay mountains to 0.00" in the interior Central Coast respectively. These two rounds of rainfall will not necessarily have a break in between them but overall are expected to remain beneficial with wet roadways being the primary impact. Unfortunately, confidence in the forecast drops off a cliff at this point. While the official forecast has rain the next 7 days, just how it happens is the tricky part. Global ensemble clusters are in good agreement of troughing off the West Coast up until Tuesday when there's a 45% chance for zonal flow [Large-scale atmospheric flow in which the east-west component is dominant] or even ridging to occur. This is reflected nicely by the ECMWF [European Center for Medium-Range Weather Forecasts model] and GEFS [NCEP Global Ensemble Forecast System] advertising staggering differences in terms of moisture content with the former being much drier than the latter. While there are deterministic solutions that are bullish and advertise a strong atmospheric river (I'm looking at you GFS [Global Forecast System: global spectral model used primarily for aviation weather forecasts; provides guidance out to 384 hours at 00, 06, 12 and 18UTC.]), these should be considered outliers at this time as the 80 member ensemble mean of the ECMWF [European Center for Medium-Range Weather Forecasts model] EPS [Ensemble Prediction System] and GEFS [NCEP Global Ensemble Forecast System] suggest brief periods of time between Monday and Thursday with integrated water vapor transport (IVT [GFS Integrated Water Vapor Transport ]) values at or above 250 kg/Mississippi which would suggest a weak atmospheric river at best. Wind will also be on the increase with the passage of each system and it goes without saying that the strength of the systems will undoubtedly have an impact on wind speeds. ∨

BLINK AND YOU MIGHT MISS THE SHORTWAVE RIDGE TOMORROW. WHILE THE
THERMOMETER MAY READ THE SAME TEMPERATURE TODAY AS IT WILL TOMORROW,
THE LIGHTER WINDS TOMORROW WILL HAVE THE SENSIBLE WEATHER FEELING
WARMER. PROBABLY OF MORE INTEREST, TOMORROW WILL BE THE DRIEST DAY
OF THE NEXT SEVEN DAYS. WHILE NOT DRY FOR QUITE A 24-HOUR PERIOD,
THE FIRST 75% OF THE DAY OR SO WILL BE DRY BEFORE A TRIPLE-POINT LOW
STARTS KNOCKING ON THE DOORSTEP. SUNDAY`S RAINFALL IS EXPECTED TO
TAKE PLACE WITHIN THE WARM SECTOR, SO STEADY, LIGHT, STRATIFORM RAIN
IS EXPECTED WITH A GRADUAL NORTHWEST TO SOUTHEAST GRADIENT OF 0.50"
IN THE NORTH BAY MOUNTAINS TO 0.01" IN THE INTERIOR CENTRAL COAST
RESPECTIVELY. MONDAY`S RAINFALL WILL BE IN THE FORM OF A COLD FRONT
SO RAINFALL INTENSITY CAN BE EXPECTED TO BE RELATIVELY HEAVIER OVER
A SHORTER PERIOD OF TIME AS COMPARED TO SUNDAY WITH A SIMILAR
(ALBEIT SHARPER) NORTHWEST TO SOUTHEAST GRADIENT OF 0.75" IN THE
NORTH BAY MOUNTAINS TO 0.00" IN THE INTERIOR CENTRAL COAST
RESPECTIVELY. THESE TWO ROUNDS OF RAINFALL WILL NOT NECESSARILY HAVE
A BREAK IN BETWEEN THEM BUT OVERALL ARE EXPECTED TO REMAIN
BENEFICIAL WITH WET ROADWAYS BEING THE PRIMARY IMPACT.
UNFORTUNATELY, CONFIDENCE IN THE FORECAST DROPS OFF A CLIFF AT THIS
POINT. WHILE THE OFFICIAL FORECAST HAS RAIN THE NEXT 7 DAYS, JUST
HOW IT HAPPENS IS THE TRICKY PART. GLOBAL ENSEMBLE CLUSTERS ARE IN
GOOD AGREEMENT OF TROUGHING OFF THE WEST COAST UP UNTIL TUESDAY WHEN
THERE`S A 45% CHANCE FOR ZONAL FLOW OR EVEN RIDGING TO OCCUR. THIS
IS REFLECTED NICELY BY THE ECMWF AND GEFS ADVERTISING STAGGERING
DIFFERENCES IN TERMS OF MOISTURE CONTENT WITH THE FORMER BEING MUCH
DRIER THAN THE LATTER. WHILE THERE ARE DETERMINISTIC SOLUTIONS THAT
ARE BULLISH AND ADVERTISE A STRONG ATMOSPHERIC RIVER (I`M LOOKING AT
YOU GFS), THESE SHOULD BE CONSIDERED OUTLIERS AT THIS TIME AS THE 80
MEMBER ENSEMBLE MEAN OF THE ECMWF EPS AND GEFS SUGGEST BRIEF PERIODS
OF TIME BETWEEN MONDAY AND THURSDAY WITH INTEGRATED WATER VAPOR
TRANSPORT (IVT) VALUES AT OR ABOVE 250 KG/MS WHICH WOULD SUGGEST A
WEAK ATMOSPHERIC RIVER AT BEST. WIND WILL ALSO BE ON THE INCREASE
WITH THE PASSAGE OF EACH SYSTEM AND IT GOES WITHOUT SAYING THAT THE
STRENGTH OF THE SYSTEMS WILL UNDOUBTEDLY HAVE AN IMPACT ON WIND
SPEEDS. [DISC]

Aviation. (18Z [11am PDT] TAFs [Terminal Aerodrome Forecasts]) issued at 10:42am PDT Friday Mar 28 2025 ∨

.AVIATION...
(18Z TAFS)
ISSUED AT 1042 AM PDT FRI MAR 28 2025 [AVIA]

Seeing a mix of MVFR [Marginal Visual Flight Rules] to VFR [Visual Flight Rules] conditions across the region late this morning, yet conditions are forecast to improve to VFR [Visual Flight Rules] as we move into the afternoon and lingering showers dissipate. Onshore winds will increase to a moderate westerly breeze this afternoon before diminishing overnight. There is about a 40% potential of low ceilings developing late tonight and into Saturday morning at MRY [Monterey CA], SNS [Salinas CA], Livermore and SJC [San Jose CA]. Thus, am hinting at it with scattered at this time. Ceilings will lift to VFR [Visual Flight Rules] by midday Saturday. ∨

SEEING A MIX OF MVFR TO VFR CONDITIONS ACROSS THE REGION LATE THIS
MORNING, YET CONDITIONS ARE FORECAST TO IMPROVE TO VFR AS WE MOVE
INTO THE AFTERNOON AND LINGERING SHOWERS DISSIPATE. ONSHORE WINDS
WILL INCREASE TO A MODERATE WESTERLY BREEZE THIS AFTERNOON BEFORE
DIMINISHING OVERNIGHT. THERE IS ABOUT A 40% POTENTIAL OF LOW
CEILINGS DEVELOPING LATE TONIGHT AND INTO SATURDAY MORNING AT MRY,
SNS, LVK AND SJC. THUS, AM HINTING AT IT WITH SCT AT THIS TIME.
CEILINGS WILL LIFT TO VFR BY MIDDAY SATURDAY. [AVI2]

Vicinity of SFO [San Francisco CA]… MVFR [Marginal Visual Flight Rules] to VFR [Visual Flight Rules] ceilings will continue to lift through late morning. A moderate westerly breeze will develop in the afternoon before diminishing overnight. VFR [Visual Flight Rules] conditions are expected through Saturday with a gentle northwesterly breeze developing by Saturday afternoon. ∨

VICINITY OF SFO...MVFR TO VFR CEILINGS WILL CONTINUE TO LIFT THROUGH
LATE MORNING. A MODERATE WESTERLY BREEZE WILL DEVELOP IN THE
AFTERNOON BEFORE DIMINISHING OVERNIGHT. VFR CONDITIONS ARE EXPECTED
THROUGH SATURDAY WITH A GENTLE NORTHWESTERLY BREEZE DEVELOPING BY
SATURDAY AFTERNOON. [AVI2]

SFO [San Francisco CA] bridge approach… similar to SFO [San Francisco CA]. ∨

SFO BRIDGE APPROACH...SIMILAR TO SFO. [AVI2]

Monterey Bay terminals… MVFR [Marginal Visual Flight Rules] to VFR [Visual Flight Rules] ceilings will continue to lift through late morning as passing rain showers exit the region. A sea breeze will bring moderate onshore winds through the afternoon before diminishing overnight. There is about a 40% potential of MVFR [Marginal Visual Flight Rules] ceilings to develop early Saturday morning, however will cover with scattered at this time. ∨

MONTEREY BAY TERMINALS...MVFR TO VFR CEILINGS WILL CONTINUE TO LIFT
THROUGH LATE MORNING AS PASSING RAIN SHOWERS EXIT THE REGION. A SEA
BREEZE WILL BRING MODERATE ONSHORE WINDS THROUGH THE AFTERNOON
BEFORE DIMINISHING OVERNIGHT. THERE IS ABOUT A 40% POTENTIAL OF MVFR
CEILINGS TO DEVELOP EARLY SATURDAY MORNING, HOWEVER WILL COVER WITH
SCT AT THIS TIME. [AVI2]

Marine. (today through Wednesday) issued at 10:42am PDT Friday Mar 28 2025 ∨

.MARINE...
(TODAY THROUGH WEDNESDAY)
ISSUED AT 1042 AM PDT FRI MAR 28 2025 [AVIA]

Very high swell will gradually subside through the day as a low amplitude short wave ridge builds. Moderate westerly winds will diminish through Friday night and become more northwesterly on Saturday. By Sunday, an approaching low pressure system will shift the winds to a strong southerly breeze with possible gale force gusts and periods of rain. ∨

VERY HIGH SWELL WILL GRADUALLY SUBSIDE THROUGH THE DAY AS A LOW
AMPLITUDE SHORT WAVE RIDGE BUILDS. MODERATE WESTERLY WINDS WILL
DIMINISH THROUGH FRIDAY NIGHT AND BECOME MORE NORTHWESTERLY ON
SATURDAY. BY SUNDAY, AN APPROACHING LOW PRESSURE SYSTEM WILL
SHIFT THE WINDS TO A STRONG SOUTHERLY BREEZE WITH POSSIBLE GALE
FORCE GUSTS AND PERIODS OF RAIN. [AVI2]

Beaches… issued at 4:41am PDT Friday Mar 28 2025 ∨

.BEACHES...
ISSUED AT 441 AM PDT FRI MAR 28 2025 [DISC]

The long period northwest swell will continue to produce large breaking waves up to 35 ft along the coast through the day today. Buoys are currently reporting a 15 ft NW swell with a period of around 15 seconds. The breaking waves will gradually diminish through the day, although the hazard will peak around the mid-day high tide. Large breaking waves will be focused on west and northwest facing beaches, with enhanced rip currents expected on all beaches. Inexperienced swimmers should stay out of the water. Beachgoers should maintain a further stand-off distance from the water than normal. Stay off of jetties and rocks, keep pets on a leash, wear a life Jacket, and never turn your back on the ocean! ∨

THE LONG PERIOD NORTHWEST SWELL WILL CONTINUE TO PRODUCE LARGE
BREAKING WAVES UP TO 35 FT ALONG THE COAST THROUGH THE DAY TODAY.
BUOYS ARE CURRENTLY REPORTING A 15 FT NW SWELL WITH A PERIOD OF
AROUND 15 SECONDS. THE BREAKING WAVES WILL GRADUALLY DIMINISH
THROUGH THE DAY, ALTHOUGH THE HAZARD WILL PEAK AROUND THE MID-DAY
HIGH TIDE. LARGE BREAKING WAVES WILL BE FOCUSED ON WEST AND
NORTHWEST FACING BEACHES, WITH ENHANCED RIP CURRENTS EXPECTED ON
ALL BEACHES. INEXPERIENCED SWIMMERS SHOULD STAY OUT OF THE WATER.
BEACHGOERS SHOULD MAINTAIN A FURTHER STAND-OFF DISTANCE FROM THE
WATER THAN NORMAL. STAY OFF OF JETTIES AND ROCKS, KEEP PETS ON A
LEASH, WEAR A LIFE JACKET, AND NEVER TURN YOUR BACK ON THE OCEAN! [DISC]

MTR Watches/Warnings/Advisories

California: High Surf Advisory until 11pm PDT this evening for CAZ006–505–509–530. ∨

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...HIGH SURF ADVISORY UNTIL 11 PM PDT THIS EVENING FOR CAZ006-505-
509-530. [WARN]

Beach hazards statement through this evening for CAZ529. ∨

     BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR CAZ529. [WRN2]

Pacific Ocean: Small Craft Advisory until 9pm PDT this evening for Monterey Bay. ∨

PZ...SMALL CRAFT ADVISORY UNTIL 9 PM PDT THIS EVENING FOR MRY BAY. [WRN2]

Small Craft Advisory until 9am PDT Saturday for Pigeon Pt [Pescadero CA] to Pt Pinos [Monterey CA] 10–60 nm [69 miles]-Pt Arena [Mendocino CA] to Pt Reyes [San Francisco CA] 0–10 nm [11 miles]-Pt Arena [Mendocino CA] to Pt Reyes [San Francisco CA] 10–60 nm [69 miles]-Pt Pinos [Monterey CA] to Pt Piedras Blancas [San Simeon CA] 0–10 nm [11 miles]. ∨

     SMALL CRAFT ADVISORY UNTIL 9 AM PDT SATURDAY FOR PIGEON PT TO PT
PINOS 10-60 NM-PT ARENA TO PT REYES 0-10 NM-PT ARENA TO PT
REYES 10-60 NM-PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM. [WRN2]

Small Craft Advisory until 3am PDT Saturday for Pigeon Pt [Pescadero CA] to Pt Pinos [Monterey CA] 0–10 nm [11 miles]-Pt Reyes [San Francisco CA] to Pigeon Pt [Pescadero CA] 0–10 nm [11 miles]. ∨

     SMALL CRAFT ADVISORY UNTIL 3 AM PDT SATURDAY FOR PIGEON PT TO PT
PINOS 0-10 NM-PT REYES TO PIGEON PT 0-10 NM. [WRN2]

Short term…sarment long term…sarment aviation…rgass marine…rgass ∨

SHORT TERM...SARMENT
LONG TERM....SARMENT
AVIATION...RGASS
MARINE...RGASS [WRN2]

VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO [LINK]

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X.COM/NWSBAYAREA
WWW.YOUTUBE.COM/NWSBAYAREA [DISC]

Weather NWS glossary About NWS point forecasts Hourly Weather Graph Long-range forecast Radar Satellite Max Temps Graphical Forecast	Area Forecast Discussion FXUS66 KMTR [Monterey CA] 281744 AFDMTR ∨ FXUS66 KMTR 281744 AFDMTR [HEAD] National Weather Service San Francisco California 10:44am PDT Fri Mar 28 2025 ∨ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN FRANCISCO CA 1044 AM PDT FRI MAR 28 2025 [HEAD] New aviation, marine. ∨ ...NEW AVIATION, MARINE... [DISC] Synopsis. Issued at 3:03am PDT Friday Mar 28 2025 ∨ .SYNOPSIS... ISSUED AT 303 AM PDT FRI MAR 28 2025 [DISC] Cool conditions and hazardous beach conditions continue today. A brief dry period Saturday precedes several rounds of rain and wind slated for next week. ∨ COOL CONDITIONS AND HAZARDOUS BEACH CONDITIONS CONTINUE TODAY. A BRIEF DRY PERIOD SATURDAY PRECEDES SEVERAL ROUNDS OF RAIN AND WIND SLATED FOR NEXT WEEK. [DISC] Short term. (today and tonight) issued at 3:03am PDT Friday Mar 28 2025 ∨ .SHORT TERM... (TODAY AND TONIGHT) ISSUED AT 303 AM PDT FRI MAR 28 2025 [DISC] Rain shower activity from a surface trough with upper level support will continue to diminish through the morning. Rainfall accumulation will be beneficial with locally higher totals along the coast and in the higher terrain due to orographic lift - the primary impact expected is wet roadways. Aside from that, expect temperatures to remain below seasonal averages and clouds to lift and decrease in coverage throughout the day as the upper-level shortwave trough ejects east. While cold conditions are not anticipated to be widespread enough for a Frost Advisory tonight, isolated portions of the higher terrain in the North Bay interior mountains, eastern Santa Clara Hills, and interior Monterey and San Benito Counties are forecast to be in the 32–36° range. As always, please protect people, pets, plants, and pipes. Last but certainly not least, a High Surf Advisory remains in effect until 11pm tonight for all Pacific coast beaches (sans northern Monterey Bay as the area has a beach hazards statement in effect until 11pm tonight). If you're planning on being near the Pacific Ocean, keep pets on a leash, stay off of jetties and rocks, wear a life Jacket, and never turn your back on the ocean! ∨ RAIN SHOWER ACTIVITY FROM A SURFACE TROUGH WITH UPPER LEVEL SUPPORT WILL CONTINUE TO DIMINISH THROUGH THE MORNING. RAINFALL ACCUMULATION WILL BE BENEFICIAL WITH LOCALLY HIGHER TOTALS ALONG THE COAST AND IN THE HIGHER TERRAIN DUE TO OROGRAPHIC LIFT - THE PRIMARY IMPACT EXPECTED IS WET ROADWAYS. ASIDE FROM THAT, EXPECT TEMPERATURES TO REMAIN BELOW SEASONAL AVERAGES AND CLOUDS TO LIFT AND DECREASE IN COVERAGE THROUGHOUT THE DAY AS THE UPPER-LEVEL SHORTWAVE TROUGH EJECTS EAST. WHILE COLD CONDITIONS ARE NOT ANTICIPATED TO BE WIDESPREAD ENOUGH FOR A FROST ADVISORY TONIGHT, ISOLATED PORTIONS OF THE HIGHER TERRAIN IN THE NORTH BAY INTERIOR MOUNTAINS, EASTERN SANTA CLARA HILLS, AND INTERIOR MONTEREY AND SAN BENITO COUNTIES ARE FORECAST TO BE IN THE 32 TO 36 DEGREE RANGE. AS ALWAYS, PLEASE PROTECT PEOPLE, PETS, PLANTS, AND PIPES. LAST BUT CERTAINLY NOT LEAST, A HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 11 PM TONIGHT FOR ALL PACIFIC COAST BEACHES (SANS NORTHERN MONTEREY BAY AS THE AREA HAS A BEACH HAZARDS STATEMENT IN EFFECT UNTIL 11 PM TONIGHT). IF YOU`RE PLANNING ON BEING NEAR THE PACIFIC OCEAN, KEEP PETS ON A LEASH, STAY OFF OF JETTIES AND ROCKS, WEAR A LIFE JACKET, AND NEVER TURN YOUR BACK ON THE OCEAN! [DISC] Long term. (Saturday through Thursday) issued at 3:03am PDT Friday Mar 28 2025 ∨ .LONG TERM... (SATURDAY THROUGH THURSDAY) ISSUED AT 303 AM PDT FRI MAR 28 2025 [DISC] Blink and you might miss the shortwave ridge tomorrow. While the thermometer may read the same temperature today as it will tomorrow, the lighter winds tomorrow will have the sensible weather feeling warmer. Probably of more interest, tomorrow will be the driest day of the next seven days. While not dry for quite a 24-hour period, the first 75% of the day or so will be dry before a triple-point low starts knocking on the doorstep. Sunday's rainfall is expected to take place within the warm sector, so steady, light, stratiform rain is expected with a gradual northwest to southeast gradient of 0.50" in the North Bay mountains to 0.01" in the interior Central Coast respectively. Monday's rainfall will be in the form of a cold front so rainfall intensity can be expected to be relatively heavier over a shorter period of time as compared to Sunday with a similar (Albeit sharper) northwest to southeast gradient of 0.75" in the North Bay mountains to 0.00" in the interior Central Coast respectively. These two rounds of rainfall will not necessarily have a break in between them but overall are expected to remain beneficial with wet roadways being the primary impact. Unfortunately, confidence in the forecast drops off a cliff at this point. While the official forecast has rain the next 7 days, just how it happens is the tricky part. Global ensemble clusters are in good agreement of troughing off the West Coast up until Tuesday when there's a 45% chance for zonal flow [Large-scale atmospheric flow in which the east-west component is dominant] or even ridging to occur. This is reflected nicely by the ECMWF [European Center for Medium-Range Weather Forecasts model] and GEFS [NCEP Global Ensemble Forecast System] advertising staggering differences in terms of moisture content with the former being much drier than the latter. While there are deterministic solutions that are bullish and advertise a strong atmospheric river (I'm looking at you GFS [Global Forecast System: global spectral model used primarily for aviation weather forecasts; provides guidance out to 384 hours at 00, 06, 12 and 18UTC.]), these should be considered outliers at this time as the 80 member ensemble mean of the ECMWF [European Center for Medium-Range Weather Forecasts model] EPS [Ensemble Prediction System] and GEFS [NCEP Global Ensemble Forecast System] suggest brief periods of time between Monday and Thursday with integrated water vapor transport (IVT [GFS Integrated Water Vapor Transport ]) values at or above 250 kg/Mississippi which would suggest a weak atmospheric river at best. Wind will also be on the increase with the passage of each system and it goes without saying that the strength of the systems will undoubtedly have an impact on wind speeds. ∨ BLINK AND YOU MIGHT MISS THE SHORTWAVE RIDGE TOMORROW. WHILE THE THERMOMETER MAY READ THE SAME TEMPERATURE TODAY AS IT WILL TOMORROW, THE LIGHTER WINDS TOMORROW WILL HAVE THE SENSIBLE WEATHER FEELING WARMER. PROBABLY OF MORE INTEREST, TOMORROW WILL BE THE DRIEST DAY OF THE NEXT SEVEN DAYS. WHILE NOT DRY FOR QUITE A 24-HOUR PERIOD, THE FIRST 75% OF THE DAY OR SO WILL BE DRY BEFORE A TRIPLE-POINT LOW STARTS KNOCKING ON THE DOORSTEP. SUNDAY`S RAINFALL IS EXPECTED TO TAKE PLACE WITHIN THE WARM SECTOR, SO STEADY, LIGHT, STRATIFORM RAIN IS EXPECTED WITH A GRADUAL NORTHWEST TO SOUTHEAST GRADIENT OF 0.50" IN THE NORTH BAY MOUNTAINS TO 0.01" IN THE INTERIOR CENTRAL COAST RESPECTIVELY. MONDAY`S RAINFALL WILL BE IN THE FORM OF A COLD FRONT SO RAINFALL INTENSITY CAN BE EXPECTED TO BE RELATIVELY HEAVIER OVER A SHORTER PERIOD OF TIME AS COMPARED TO SUNDAY WITH A SIMILAR (ALBEIT SHARPER) NORTHWEST TO SOUTHEAST GRADIENT OF 0.75" IN THE NORTH BAY MOUNTAINS TO 0.00" IN THE INTERIOR CENTRAL COAST RESPECTIVELY. THESE TWO ROUNDS OF RAINFALL WILL NOT NECESSARILY HAVE A BREAK IN BETWEEN THEM BUT OVERALL ARE EXPECTED TO REMAIN BENEFICIAL WITH WET ROADWAYS BEING THE PRIMARY IMPACT. UNFORTUNATELY, CONFIDENCE IN THE FORECAST DROPS OFF A CLIFF AT THIS POINT. WHILE THE OFFICIAL FORECAST HAS RAIN THE NEXT 7 DAYS, JUST HOW IT HAPPENS IS THE TRICKY PART. GLOBAL ENSEMBLE CLUSTERS ARE IN GOOD AGREEMENT OF TROUGHING OFF THE WEST COAST UP UNTIL TUESDAY WHEN THERE`S A 45% CHANCE FOR ZONAL FLOW OR EVEN RIDGING TO OCCUR. THIS IS REFLECTED NICELY BY THE ECMWF AND GEFS ADVERTISING STAGGERING DIFFERENCES IN TERMS OF MOISTURE CONTENT WITH THE FORMER BEING MUCH DRIER THAN THE LATTER. WHILE THERE ARE DETERMINISTIC SOLUTIONS THAT ARE BULLISH AND ADVERTISE A STRONG ATMOSPHERIC RIVER (I`M LOOKING AT YOU GFS), THESE SHOULD BE CONSIDERED OUTLIERS AT THIS TIME AS THE 80 MEMBER ENSEMBLE MEAN OF THE ECMWF EPS AND GEFS SUGGEST BRIEF PERIODS OF TIME BETWEEN MONDAY AND THURSDAY WITH INTEGRATED WATER VAPOR TRANSPORT (IVT) VALUES AT OR ABOVE 250 KG/MS WHICH WOULD SUGGEST A WEAK ATMOSPHERIC RIVER AT BEST. WIND WILL ALSO BE ON THE INCREASE WITH THE PASSAGE OF EACH SYSTEM AND IT GOES WITHOUT SAYING THAT THE STRENGTH OF THE SYSTEMS WILL UNDOUBTEDLY HAVE AN IMPACT ON WIND SPEEDS. [DISC] Aviation. (18Z [11am PDT] TAFs [Terminal Aerodrome Forecasts]) issued at 10:42am PDT Friday Mar 28 2025 ∨ .AVIATION... (18Z TAFS) ISSUED AT 1042 AM PDT FRI MAR 28 2025 [AVIA] Seeing a mix of MVFR [Marginal Visual Flight Rules] to VFR [Visual Flight Rules] conditions across the region late this morning, yet conditions are forecast to improve to VFR [Visual Flight Rules] as we move into the afternoon and lingering showers dissipate. Onshore winds will increase to a moderate westerly breeze this afternoon before diminishing overnight. There is about a 40% potential of low ceilings developing late tonight and into Saturday morning at MRY [Monterey CA], SNS [Salinas CA], Livermore and SJC [San Jose CA]. Thus, am hinting at it with scattered at this time. Ceilings will lift to VFR [Visual Flight Rules] by midday Saturday. ∨ SEEING A MIX OF MVFR TO VFR CONDITIONS ACROSS THE REGION LATE THIS MORNING, YET CONDITIONS ARE FORECAST TO IMPROVE TO VFR AS WE MOVE INTO THE AFTERNOON AND LINGERING SHOWERS DISSIPATE. ONSHORE WINDS WILL INCREASE TO A MODERATE WESTERLY BREEZE THIS AFTERNOON BEFORE DIMINISHING OVERNIGHT. THERE IS ABOUT A 40% POTENTIAL OF LOW CEILINGS DEVELOPING LATE TONIGHT AND INTO SATURDAY MORNING AT MRY, SNS, LVK AND SJC. THUS, AM HINTING AT IT WITH SCT AT THIS TIME. CEILINGS WILL LIFT TO VFR BY MIDDAY SATURDAY. [AVI2] Vicinity of SFO [San Francisco CA]… MVFR [Marginal Visual Flight Rules] to VFR [Visual Flight Rules] ceilings will continue to lift through late morning. A moderate westerly breeze will develop in the afternoon before diminishing overnight. VFR [Visual Flight Rules] conditions are expected through Saturday with a gentle northwesterly breeze developing by Saturday afternoon. ∨ VICINITY OF SFO...MVFR TO VFR CEILINGS WILL CONTINUE TO LIFT THROUGH LATE MORNING. A MODERATE WESTERLY BREEZE WILL DEVELOP IN THE AFTERNOON BEFORE DIMINISHING OVERNIGHT. VFR CONDITIONS ARE EXPECTED THROUGH SATURDAY WITH A GENTLE NORTHWESTERLY BREEZE DEVELOPING BY SATURDAY AFTERNOON. [AVI2] SFO [San Francisco CA] bridge approach… similar to SFO [San Francisco CA]. ∨ SFO BRIDGE APPROACH...SIMILAR TO SFO. [AVI2] Monterey Bay terminals… MVFR [Marginal Visual Flight Rules] to VFR [Visual Flight Rules] ceilings will continue to lift through late morning as passing rain showers exit the region. A sea breeze will bring moderate onshore winds through the afternoon before diminishing overnight. There is about a 40% potential of MVFR [Marginal Visual Flight Rules] ceilings to develop early Saturday morning, however will cover with scattered at this time. ∨ MONTEREY BAY TERMINALS...MVFR TO VFR CEILINGS WILL CONTINUE TO LIFT THROUGH LATE MORNING AS PASSING RAIN SHOWERS EXIT THE REGION. A SEA BREEZE WILL BRING MODERATE ONSHORE WINDS THROUGH THE AFTERNOON BEFORE DIMINISHING OVERNIGHT. THERE IS ABOUT A 40% POTENTIAL OF MVFR CEILINGS TO DEVELOP EARLY SATURDAY MORNING, HOWEVER WILL COVER WITH SCT AT THIS TIME. [AVI2] Marine. (today through Wednesday) issued at 10:42am PDT Friday Mar 28 2025 ∨ .MARINE... (TODAY THROUGH WEDNESDAY) ISSUED AT 1042 AM PDT FRI MAR 28 2025 [AVIA] Very high swell will gradually subside through the day as a low amplitude short wave ridge builds. Moderate westerly winds will diminish through Friday night and become more northwesterly on Saturday. By Sunday, an approaching low pressure system will shift the winds to a strong southerly breeze with possible gale force gusts and periods of rain. ∨ VERY HIGH SWELL WILL GRADUALLY SUBSIDE THROUGH THE DAY AS A LOW AMPLITUDE SHORT WAVE RIDGE BUILDS. MODERATE WESTERLY WINDS WILL DIMINISH THROUGH FRIDAY NIGHT AND BECOME MORE NORTHWESTERLY ON SATURDAY. BY SUNDAY, AN APPROACHING LOW PRESSURE SYSTEM WILL SHIFT THE WINDS TO A STRONG SOUTHERLY BREEZE WITH POSSIBLE GALE FORCE GUSTS AND PERIODS OF RAIN. [AVI2] Beaches… issued at 4:41am PDT Friday Mar 28 2025 ∨ .BEACHES... ISSUED AT 441 AM PDT FRI MAR 28 2025 [DISC] The long period northwest swell will continue to produce large breaking waves up to 35 ft along the coast through the day today. Buoys are currently reporting a 15 ft NW swell with a period of around 15 seconds. The breaking waves will gradually diminish through the day, although the hazard will peak around the mid-day high tide. Large breaking waves will be focused on west and northwest facing beaches, with enhanced rip currents expected on all beaches. Inexperienced swimmers should stay out of the water. Beachgoers should maintain a further stand-off distance from the water than normal. Stay off of jetties and rocks, keep pets on a leash, wear a life Jacket, and never turn your back on the ocean! ∨ THE LONG PERIOD NORTHWEST SWELL WILL CONTINUE TO PRODUCE LARGE BREAKING WAVES UP TO 35 FT ALONG THE COAST THROUGH THE DAY TODAY. BUOYS ARE CURRENTLY REPORTING A 15 FT NW SWELL WITH A PERIOD OF AROUND 15 SECONDS. THE BREAKING WAVES WILL GRADUALLY DIMINISH THROUGH THE DAY, ALTHOUGH THE HAZARD WILL PEAK AROUND THE MID-DAY HIGH TIDE. LARGE BREAKING WAVES WILL BE FOCUSED ON WEST AND NORTHWEST FACING BEACHES, WITH ENHANCED RIP CURRENTS EXPECTED ON ALL BEACHES. INEXPERIENCED SWIMMERS SHOULD STAY OUT OF THE WATER. BEACHGOERS SHOULD MAINTAIN A FURTHER STAND-OFF DISTANCE FROM THE WATER THAN NORMAL. STAY OFF OF JETTIES AND ROCKS, KEEP PETS ON A LEASH, WEAR A LIFE JACKET, AND NEVER TURN YOUR BACK ON THE OCEAN! [DISC] MTR Watches/Warnings/Advisories California: High Surf Advisory until 11pm PDT this evening for CAZ006–505–509–530. ∨ .MTR WATCHES/WARNINGS/ADVISORIES... CA...HIGH SURF ADVISORY UNTIL 11 PM PDT THIS EVENING FOR CAZ006-505- 509-530. [WARN] Beach hazards statement through this evening for CAZ529. ∨ BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR CAZ529. [WRN2] Pacific Ocean: Small Craft Advisory until 9pm PDT this evening for Monterey Bay. ∨ PZ...SMALL CRAFT ADVISORY UNTIL 9 PM PDT THIS EVENING FOR MRY BAY. [WRN2] Small Craft Advisory until 9am PDT Saturday for Pigeon Pt [Pescadero CA] to Pt Pinos [Monterey CA] 10–60 nm [69 miles]-Pt Arena [Mendocino CA] to Pt Reyes [San Francisco CA] 0–10 nm [11 miles]-Pt Arena [Mendocino CA] to Pt Reyes [San Francisco CA] 10–60 nm [69 miles]-Pt Pinos [Monterey CA] to Pt Piedras Blancas [San Simeon CA] 0–10 nm [11 miles]. ∨ SMALL CRAFT ADVISORY UNTIL 9 AM PDT SATURDAY FOR PIGEON PT TO PT PINOS 10-60 NM-PT ARENA TO PT REYES 0-10 NM-PT ARENA TO PT REYES 10-60 NM-PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM. [WRN2] Small Craft Advisory until 3am PDT Saturday for Pigeon Pt [Pescadero CA] to Pt Pinos [Monterey CA] 0–10 nm [11 miles]-Pt Reyes [San Francisco CA] to Pigeon Pt [Pescadero CA] 0–10 nm [11 miles]. ∨ SMALL CRAFT ADVISORY UNTIL 3 AM PDT SATURDAY FOR PIGEON PT TO PT PINOS 0-10 NM-PT REYES TO PIGEON PT 0-10 NM. [WRN2] Short term…sarment long term…sarment aviation…rgass marine…rgass ∨ SHORT TERM...SARMENT LONG TERM....SARMENT AVIATION...RGASS MARINE...RGASS [WRN2] VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO [LINK] Follow us on Facebook, x, and YouTube at: www.facebook.com/nwsbayarea x.com/nwsbayarea www.youtube.com/nwsbayarea ∨ FOLLOW US ON FACEBOOK, X, AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSBAYAREA X.COM/NWSBAYAREA WWW.YOUTUBE.COM/NWSBAYAREA [DISC]	Point Forecast Half Moon Bay Airport 28 Mar 11:15am PDT Today Partly sunny, with a high near 57°. West wind 8 to 11 mph. Tonight Partly cloudy, with a low around 45°. West wind 5 to 9 mph. Saturday Increasing clouds, with a high near 56°. Light NNW wind becoming WNW 5 to 10 mph in the morning. Saturday Night A 40% chance of rain after 11pm. Cloudy, with a low around 46°. WNW wind around 6 mph becoming calm. New precipitation amounts of less than a tenth of an inch possible. Sunday Rain. High near 59°. SE wind 9 to 14 mph increasing to 15 to 20 mph in the afternoon. Winds could gust as high as 29 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible. Sunday Night A 50% chance of rain. Mostly cloudy, with a low around 49°. New precipitation amounts of less than a tenth of an inch possible. Monday Rain likely. Mostly cloudy, with a high near 57°. Chance of precipitation is 70%. Monday Night A chance of rain, mainly before 11pm. Mostly cloudy, with a low around 46°. Tuesday A chance of rain. Partly sunny, with a high near 56°. Tuesday Night A chance of rain. Mostly cloudy, with a low around 45°. Wednesday A chance of rain. Partly sunny, with a high near 56°. Wednesday Night A chance of rain. Mostly cloudy, with a low around 45°. Thursday A chance of rain. Partly sunny, with a high near 56°. Today Partly sunny, with a high near 57. West wind 8 to 11 mph. Tonight Partly cloudy, with a low around 45. West wind 5 to 9 mph. Saturday Increasing clouds, with a high near 56. Light north northwest wind becoming west northwest 5 to 10 mph in the morning. Saturday Night A 40 percent chance of rain after 11pm. Cloudy, with a low around 46. West northwest wind around 6 mph becoming calm. New precipitation amounts of less than a tenth of an inch possible. Sunday Rain. High near 59. Southeast wind 9 to 14 mph increasing to 15 to 20 mph in the afternoon. Winds could gust as high as 29 mph. Chance of precipitation is 90%. New precipitation amounts between a tenth and quarter of an inch possible. Sunday Night A 50 percent chance of rain. Mostly cloudy, with a low around 49. New precipitation amounts of less than a tenth of an inch possible. Monday Rain likely. Mostly cloudy, with a high near 57. Chance of precipitation is 70%. Monday Night A chance of rain, mainly before 11pm. Mostly cloudy, with a low around 46. Tuesday A chance of rain. Partly sunny, with a high near 56. Tuesday Night A chance of rain. Mostly cloudy, with a low around 45. Wednesday A chance of rain. Partly sunny, with a high near 56. Wednesday Night A chance of rain. Mostly cloudy, with a low around 45. Thursday A chance of rain. Partly sunny, with a high near 56.
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