Montara CA WX RSS feed

Area Forecast Discussion

FXUS66 KMTR [Monterey CA] 090447 AFDMTR ∨

FXUS66 KMTR 090447
AFDMTR [HEAD]

National Weather Service San Francisco California 9:47pm PDT Tue Apr 8 2025 ∨

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
947 PM PDT TUE APR 8 2025 [HEAD]

New aviation. ∨

...NEW AVIATION... [DISC]

Synopsis. Issued at 7:50pm PDT Tuesday April 8 2025 ∨

.SYNOPSIS...
ISSUED AT 750 PM PDT TUE APR 8 2025 [DISC]

Warm and dry conditions persist through the week with minor heat impacts for those extremely sensitive to heat. ∨

WARM AND DRY CONDITIONS PERSIST THROUGH THE WEEK WITH MINOR HEAT
IMPACTS FOR THOSE EXTREMELY SENSITIVE TO HEAT. [DISC]

Update. Issued at 7:50pm PDT Tuesday April 8 2025 ∨

.UPDATE...
ISSUED AT 750 PM PDT TUE APR 8 2025 [DISC]

The inherited short term forecast is in good shape with no real changes needed. Mostly clear skies are anticipated across the Bay Area and Central Coast tonight. Our 00Z [5pm PDT] evening weather balloon from Oakland has revealed that the column is beginning to dry as a more subsident airmass starts to build across the region. The drier air should mean that pockets of fog are confined to valleys and areas along the coast and the evening NWP appears to capture this well. The fog could be dense in spots, largely across river valleys and across coastal areas. While coverage is expected to be less tonight compared to Tuesday morning, motorists commuting early Wednesday morning should be cognizant of sudden changes in visibility ∨

THE INHERITED SHORT TERM FORECAST IS IN GOOD SHAPE WITH NO
REAL CHANGES NEEDED. MOSTLY CLEAR SKIES ARE ANTICIPATED ACROSS
THE BAY AREA AND CENTRAL COAST TONIGHT. OUR 00Z EVENING WEATHER
BALLOON FROM OAKLAND HAS REVEALED THAT THE COLUMN IS BEGINNING TO
DRY AS A MORE SUBSIDENT AIRMASS STARTS TO BUILD ACROSS THE REGION.
THE DRIER AIR SHOULD MEAN THAT POCKETS OF FOG ARE CONFINED TO
VALLEYS AND AREAS ALONG THE COAST AND THE EVENING NWP APPEARS TO
CAPTURE THIS WELL. THE FOG COULD BE DENSE IN SPOTS, LARGELY ACROSS
RIVER VALLEYS AND ACROSS COASTAL AREAS. WHILE COVERAGE IS
EXPECTED TO BE LESS TONIGHT COMPARED TO TUESDAY MORNING, MOTORISTS
COMMUTING EARLY WEDNESDAY MORNING SHOULD BE COGNIZANT OF SUDDEN
CHANGES IN VISIBILITY [DISC]

Otherwise, our warming trend will be in full swing tomorrow with "minor" heat risk expanding across the area. For more details, see the discussion below. ∨

OTHERWISE, OUR WARMING TREND WILL BE IN FULL SWING TOMORROW WITH
"MINOR" HEAT RISK EXPANDING ACROSS THE AREA. FOR MORE DETAILS, SEE
THE DISCUSSION BELOW. [DISC]

Short term. (this evening through Wednesday) issued at 1:11pm PDT Tuesday April 8 2025 ∨

.SHORT TERM...
(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 111 PM PDT TUE APR 8 2025 [DISC]

Longwave ridging begins to build today resulting in near normal temperatures and minor heatrisk. Let's say that your favorite team is playing a (re)match in San Jose this evening around sunset and you are concerned about the heat. Fortunately, after the maximum temperature is reached this afternoon and sun angle lowers, conditions will cool off quickly. In fact, clear and calm conditions will result in radiational cooling overnight. ∨

LONGWAVE RIDGING BEGINS TO BUILD TODAY RESULTING IN NEAR NORMAL
TEMPERATURES AND MINOR HEATRISK. LET`S SAY THAT YOUR FAVORITE TEAM
IS PLAYING A (RE)MATCH IN SAN JOSE THIS EVENING AROUND SUNSET AND
YOU ARE CONCERNED ABOUT THE HEAT. FORTUNATELY, AFTER THE MAXIMUM
TEMPERATURE IS REACHED THIS AFTERNOON AND SUN ANGLE LOWERS,
CONDITIONS WILL COOL OFF QUICKLY. IN FACT, CLEAR AND CALM CONDITIONS
WILL RESULT IN RADIATIONAL COOLING OVERNIGHT. [DISC]

NWS [National Weather Service] minor heatrisk: ∨

NWS MINOR HEATRISK: [DISC]

- heat of this type is tolerated by most; however there is a minor risk for extremely heat-sensitive groups to experience negative heat-related health effects. ∨

- HEAT OF THIS TYPE IS TOLERATED BY MOST; HOWEVER THERE IS A MINOR RISK
FOR EXTREMELY HEAT-SENSITIVE GROUPS TO EXPERIENCE NEGATIVE
HEAT- RELATED HEALTH EFFECTS. [DISC]

- the risk is primarily for those who are extremely sensitive to heat, especially when outdoors without effective cooling and/or adequate hydration. ∨

- THE RISK IS PRIMARILY FOR THOSE WHO ARE EXTREMELY SENSITIVE TO HEAT,
ESPECIALLY WHEN OUTDOORS WITHOUT EFFECTIVE COOLING AND/OR
ADEQUATE HYDRATION. [DISC]

- very common heat. ∨

- VERY COMMON HEAT. [DISC]

- for those at risk, actions that can be taken: increase hydration, reduce time spent outdoors or stay in the shade when the sun is strongest, and open windows at night and use fans to bring cooler air inside buildings. ∨

- FOR THOSE AT RISK, ACTIONS THAT CAN BE TAKEN: INCREASE
HYDRATION, REDUCE TIME SPENT OUTDOORS OR STAY IN THE SHADE WHEN
THE SUN IS STRONGEST, AND OPEN WINDOWS AT NIGHT AND USE FANS TO
BRING COOLER AIR INSIDE BUILDINGS. [DISC]

Long term. (Wednesday night through next Monday) issued at 1:11pm PDT Tuesday April 8 2025 ∨

.LONG TERM...
(WEDNESDAY NIGHT THROUGH NEXT MONDAY)
ISSUED AT 111 PM PDT TUE APR 8 2025 [DISC]

Let's take a deep dive into the maximum temperature forecast for Wednesday and Thursday. The forecast may seem straightforward, but it's actually a lot more nuanced than one might think. For those of you that don't know, the National Weather Service (NWS [National Weather Service]) uses the national blend of models (NBM) as a starting point for building the forecast. There were multiple sites along the coast where the deterministic forecast fell below the whisker (10th percentile) of the box and whisker plot. Because of this, maximum temperatures for Wednesday and Thursday for areas that would be impacted by a 500 foot marine layer are a 50/50 blend of NBM/NBM 50th percentile. The marine layer will add even more complexity. As of now, HREF guidance does not show high probabilities of low clouds returning tonight, but if they do, expect them to primarily remain confined to the coast. If low clouds do form and end up sticking around for a prolonged amount of time, that'll certainly impact maximum temperatures. Think of a place like San Francisco. The maximum temperature of 2025 (80°) occurred on March 25th, but more importantly for this scenario is that it occurred at 1:43pm (before onshore flow kicked in). So hopefully I have painted the picture in your mind that if clouds linger in a coastal area for too long, the surface will not be able to warm as much as it would have without the clouds, thus a very boom or bust forecast at the immediate coast. Nonetheless, Wednesday will have the warmest conditions across the board thanks to the longwave ridge axis being overhead. The gradual cooldown begins Thursday as heights begin to ever so slightly fall as an upper-level shortwave trough in the Pacific Northwest nudges the ridge to the east. A surface low and its attendant weak, dry cold front will sweep through the region on Friday bringing with it an increase in northerly winds. Global ensemble cluster agreement begins to diverge Saturday, particularly in the amplitude and location of the upper-level shortwave trough. This lack in confidence gets compounded in the following days as the progression of the longwave pattern gets called into question. There's a very real possibility that an upper-level shortwave ridge will be undercut by an upper-level shortwave trough right across our region. All in all no widespread impacts aside from minor heatrisk are expected through the forecast period with no rain in sight. ∨

LET`S TAKE A DEEP DIVE INTO THE MAXIMUM TEMPERATURE FORECAST FOR
WEDNESDAY AND THURSDAY. THE FORECAST MAY SEEM STRAIGHTFORWARD, BUT
IT`S ACTUALLY A LOT MORE NUANCED THAN ONE MIGHT THINK. FOR THOSE OF
YOU THAT DON`T KNOW, THE NATIONAL WEATHER SERVICE (NWS) USES THE
NATIONAL BLEND OF MODELS (NBM) AS A STARTING POINT FOR BUILDING THE
FORECAST. THERE WERE MULTIPLE SITES ALONG THE COAST WHERE THE
DETERMINISTIC FORECAST FELL BELOW THE WHISKER (10TH PERCENTILE) OF
THE BOX AND WHISKER PLOT. BECAUSE OF THIS, MAXIMUM TEMPERATURES FOR
WEDNESDAY AND THURSDAY FOR AREAS THAT WOULD BE IMPACTED BY A 500
FOOT MARINE LAYER ARE A 50/50 BLEND OF NBM/NBM 50TH PERCENTILE. THE
MARINE LAYER WILL ADD EVEN MORE COMPLEXITY. AS OF NOW, HREF GUIDANCE
DOES NOT SHOW HIGH PROBABILITIES OF LOW CLOUDS RETURNING TONIGHT,
BUT IF THEY DO, EXPECT THEM TO PRIMARILY REMAIN CONFINED TO THE
COAST. IF LOW CLOUDS DO FORM AND END UP STICKING AROUND FOR A
PROLONGED AMOUNT OF TIME, THAT`LL CERTAINLY IMPACT MAXIMUM
TEMPERATURES. THINK OF A PLACE LIKE SAN FRANCISCO. THE MAXIMUM
TEMPERATURE OF 2025 (80 DEGREES) OCCURRED ON MARCH 25TH, BUT MORE
IMPORTANTLY FOR THIS SCENARIO IS THAT IT OCCURRED AT 1:43 PM (BEFORE
ONSHORE FLOW KICKED IN). SO HOPEFULLY I HAVE PAINTED THE PICTURE IN
YOUR MIND THAT IF CLOUDS LINGER IN A COASTAL AREA FOR TOO LONG,
THE SURFACE WILL NOT BE ABLE TO WARM AS MUCH AS IT WOULD HAVE
WITHOUT THE CLOUDS, THUS A VERY BOOM OR BUST FORECAST AT THE
IMMEDIATE COAST. NONETHELESS, WEDNESDAY WILL HAVE THE WARMEST
CONDITIONS ACROSS THE BOARD THANKS TO THE LONGWAVE RIDGE AXIS
BEING OVERHEAD. THE GRADUAL COOLDOWN BEGINS THURSDAY AS HEIGHTS
BEGIN TO EVER SO SLIGHTLY FALL AS AN UPPER-LEVEL SHORTWAVE TROUGH
IN THE PACIFIC NORTHWEST NUDGES THE RIDGE TO THE EAST. A SURFACE
LOW AND ITS ATTENDANT WEAK, DRY COLD FRONT WILL SWEEP THROUGH THE
REGION ON FRIDAY BRINGING WITH IT AN INCREASE IN NORTHERLY WINDS.
GLOBAL ENSEMBLE CLUSTER AGREEMENT BEGINS TO DIVERGE SATURDAY,
PARTICULARLY IN THE AMPLITUDE AND LOCATION OF THE UPPER-LEVEL
SHORTWAVE TROUGH. THIS LACK IN CONFIDENCE GETS COMPOUNDED IN THE
FOLLOWING DAYS AS THE PROGRESSION OF THE LONGWAVE PATTERN GETS
CALLED INTO QUESTION. THERE`S A VERY REAL POSSIBILITY THAT AN
UPPER-LEVEL SHORTWAVE RIDGE WILL BE UNDERCUT BY AN UPPER-LEVEL
SHORTWAVE TROUGH RIGHT ACROSS OUR REGION. ALL IN ALL NO
WIDESPREAD IMPACTS ASIDE FROM MINOR HEATRISK ARE EXPECTED THROUGH
THE FORECAST PERIOD WITH NO RAIN IN SIGHT. [DISC]

Aviation. (06Z [11pm PDT] TAFs [Terminal Aerodrome Forecasts]) issued at 9:46pm PDT Tuesday April 8 2025 ∨

.AVIATION...
(06Z TAFS)
ISSUED AT 946 PM PDT TUE APR 8 2025 [AVIA]

While the rest of the TAF [Terminal Aerodrome Forecast] sites stay VFR [Visual Flight Rules], haf and STS [Santa Rosa CA] will see ceilings in the late night and early morning, with some fog as well at STS [Santa Rosa CA]. Winds become weak into the night with most sites becoming variable due to more localized effects. Ceilings and fog erodes into the mid morning on Wednesday, leading to widespread VFR [Visual Flight Rules]. Moderate west winds will be slow to build into Wednesday, arriving in the late morning and afternoon. Winds reduce again that evening and into the night. Ceilings build along the coast into the early night, affecting haf, and look to slowly move inland early Thursday morning. ∨

WHILE THE REST OF THE TAF SITES STAY VFR, HAF AND STS WILL SEE CIGS
IN THE LATE NIGHT AND EARLY MORNING, WITH SOME FOG AS WELL AT STS.
WINDS BECOME WEAK INTO THE NIGHT WITH MOST SITES BECOMING VARIABLE
DUE TO MORE LOCALIZED EFFECTS.  CIGS AND FOG ERODES INTO THE MID
MORNING ON WEDNESDAY, LEADING TO WIDESPREAD VFR. MODERATE WEST WINDS
WILL BE SLOW TO BUILD INTO WEDNESDAY, ARRIVING IN THE LATE MORNING
AND AFTERNOON. WINDS REDUCE AGAIN THAT EVENING AND INTO THE NIGHT.
CIGS BUILD ALONG THE COAST INTO THE EARLY NIGHT, AFFECTING HAF, AND
LOOK TO SLOWLY MOVE INLAND EARLY THURSDAY MORNING. [AVI2]

Vicinity of SFO [San Francisco CA]… VFR [Visual Flight Rules] lasts through early Thursday. Winds have reduced and look to stay moderate through much of the night. These winds become light and variable for early Wednesday morning. Expect west winds to build again into Wednesday afternoon before reducing again into that night. IFR [Instrument Flight Rules] ceilings arrive into early Thursday morning along with a slight increase in westerly winds. ∨

VICINITY OF SFO...VFR LASTS THROUGH EARLY THURSDAY. WINDS HAVE
REDUCED AND LOOK TO STAY MODERATE THROUGH MUCH OF THE NIGHT. THESE
WINDS BECOME LIGHT AND VARIABLE FOR EARLY WEDNESDAY MORNING. EXPECT
WEST WINDS TO BUILD AGAIN INTO WEDNESDAY AFTERNOON BEFORE REDUCING
AGAIN INTO THAT NIGHT. IFR CIGS ARRIVE INTO EARLY THURSDAY MORNING
ALONG WITH A SLIGHT INCREASE IN WESTERLY WINDS. [AVI2]

SFO [San Francisco CA] bridge approach… IFR [Instrument Flight Rules] ceilings build slightly later than SFO [San Francisco CA] into Thursday morning. ∨

SFO BRIDGE APPROACH...IFR CIGS BUILD SLIGHTLY LATER THAN SFO INTO
THURSDAY MORNING. [AVI2]

Monterey Bay terminals… VFR [Visual Flight Rules] through the TAF [Terminal Aerodrome Forecast] period. Light winds look to last through the night and into Wednesday afternoon. Low-level cloud cover fills over the Monterey Bay itself in the late night but fails to make it over the terminals. Expect cloud cover to thin by the mid morning, with moderate westerly winds building that afternoon. These winds last into the mid to late evening before becoming light again. ∨

MONTEREY BAY TERMINALS...VFR THROUGH THE TAF PERIOD. LIGHT WINDS
LOOK TO LAST THROUGH THE NIGHT AND INTO WEDNESDAY AFTERNOON. LOW-
LEVEL CLOUD COVER FILLS OVER THE MONTEREY BAY ITSELF IN THE LATE
NIGHT BUT FAILS TO MAKE IT OVER THE TERMINALS. EXPECT CLOUD COVER TO
THIN BY THE MID MORNING, WITH MODERATE WESTERLY WINDS BUILDING THAT
AFTERNOON. THESE WINDS LAST INTO THE MID TO LATE EVENING BEFORE
BECOMING LIGHT AGAIN. [AVI2]

Marine. (tonight through next Monday) issued at 6:11pm PDT Tuesday April 8 2025 ∨

.MARINE...
(TONIGHT THROUGH NEXT MONDAY)
ISSUED AT 611 PM PDT TUE APR 8 2025 [AVIA]

Northerly flow will prevail over the coastal waters through the week. Winds will be locally stronger Tuesday afternoon into Wednesday south of Point Sur [Big Sur CA]. Expect a gradual improvement of the sea state as swell heights subside through midweek. A larger swell will rebuild heading into the weekend. ∨

NORTHERLY FLOW WILL PREVAIL OVER THE COASTAL WATERS THROUGH THE
WEEK. WINDS WILL BE LOCALLY STRONGER TUESDAY AFTERNOON INTO
WEDNESDAY SOUTH OF POINT SUR. EXPECT A GRADUAL IMPROVEMENT OF THE
SEA STATE AS SWELL HEIGHTS SUBSIDE THROUGH MIDWEEK. A LARGER SWELL
WILL REBUILD HEADING INTO THE WEEKEND. [AVI2]

MTR Watches/Warnings/Advisories

California: none.
Pacific Ocean: Small Craft Advisory until 3am PDT Wednesday for Pt Pinos [Monterey CA] to Pt Piedras Blancas [San Simeon CA] 0–10 nm [11 miles]. ∨

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 3 AM PDT WEDNESDAY FOR PT PINOS TO PT
PIEDRAS BLANCAS 0-10 NM. [WARN]

Short term…sarment long term…sarment aviation…murdock marine…MM ∨

SHORT TERM...SARMENT
LONG TERM....SARMENT
AVIATION...MURDOCK
MARINE...MM [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 [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] 090447 AFDMTR ∨ FXUS66 KMTR 090447 AFDMTR [HEAD] National Weather Service San Francisco California 9:47pm PDT Tue Apr 8 2025 ∨ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN FRANCISCO CA 947 PM PDT TUE APR 8 2025 [HEAD] New aviation. ∨ ...NEW AVIATION... [DISC] Synopsis. Issued at 7:50pm PDT Tuesday April 8 2025 ∨ .SYNOPSIS... ISSUED AT 750 PM PDT TUE APR 8 2025 [DISC] Warm and dry conditions persist through the week with minor heat impacts for those extremely sensitive to heat. ∨ WARM AND DRY CONDITIONS PERSIST THROUGH THE WEEK WITH MINOR HEAT IMPACTS FOR THOSE EXTREMELY SENSITIVE TO HEAT. [DISC] Update. Issued at 7:50pm PDT Tuesday April 8 2025 ∨ .UPDATE... ISSUED AT 750 PM PDT TUE APR 8 2025 [DISC] The inherited short term forecast is in good shape with no real changes needed. Mostly clear skies are anticipated across the Bay Area and Central Coast tonight. Our 00Z [5pm PDT] evening weather balloon from Oakland has revealed that the column is beginning to dry as a more subsident airmass starts to build across the region. The drier air should mean that pockets of fog are confined to valleys and areas along the coast and the evening NWP appears to capture this well. The fog could be dense in spots, largely across river valleys and across coastal areas. While coverage is expected to be less tonight compared to Tuesday morning, motorists commuting early Wednesday morning should be cognizant of sudden changes in visibility ∨ THE INHERITED SHORT TERM FORECAST IS IN GOOD SHAPE WITH NO REAL CHANGES NEEDED. MOSTLY CLEAR SKIES ARE ANTICIPATED ACROSS THE BAY AREA AND CENTRAL COAST TONIGHT. OUR 00Z EVENING WEATHER BALLOON FROM OAKLAND HAS REVEALED THAT THE COLUMN IS BEGINNING TO DRY AS A MORE SUBSIDENT AIRMASS STARTS TO BUILD ACROSS THE REGION. THE DRIER AIR SHOULD MEAN THAT POCKETS OF FOG ARE CONFINED TO VALLEYS AND AREAS ALONG THE COAST AND THE EVENING NWP APPEARS TO CAPTURE THIS WELL. THE FOG COULD BE DENSE IN SPOTS, LARGELY ACROSS RIVER VALLEYS AND ACROSS COASTAL AREAS. WHILE COVERAGE IS EXPECTED TO BE LESS TONIGHT COMPARED TO TUESDAY MORNING, MOTORISTS COMMUTING EARLY WEDNESDAY MORNING SHOULD BE COGNIZANT OF SUDDEN CHANGES IN VISIBILITY [DISC] Otherwise, our warming trend will be in full swing tomorrow with "minor" heat risk expanding across the area. For more details, see the discussion below. ∨ OTHERWISE, OUR WARMING TREND WILL BE IN FULL SWING TOMORROW WITH "MINOR" HEAT RISK EXPANDING ACROSS THE AREA. FOR MORE DETAILS, SEE THE DISCUSSION BELOW. [DISC] Short term. (this evening through Wednesday) issued at 1:11pm PDT Tuesday April 8 2025 ∨ .SHORT TERM... (THIS EVENING THROUGH WEDNESDAY) ISSUED AT 111 PM PDT TUE APR 8 2025 [DISC] Longwave ridging begins to build today resulting in near normal temperatures and minor heatrisk. Let's say that your favorite team is playing a (re)match in San Jose this evening around sunset and you are concerned about the heat. Fortunately, after the maximum temperature is reached this afternoon and sun angle lowers, conditions will cool off quickly. In fact, clear and calm conditions will result in radiational cooling overnight. ∨ LONGWAVE RIDGING BEGINS TO BUILD TODAY RESULTING IN NEAR NORMAL TEMPERATURES AND MINOR HEATRISK. LET`S SAY THAT YOUR FAVORITE TEAM IS PLAYING A (RE)MATCH IN SAN JOSE THIS EVENING AROUND SUNSET AND YOU ARE CONCERNED ABOUT THE HEAT. FORTUNATELY, AFTER THE MAXIMUM TEMPERATURE IS REACHED THIS AFTERNOON AND SUN ANGLE LOWERS, CONDITIONS WILL COOL OFF QUICKLY. IN FACT, CLEAR AND CALM CONDITIONS WILL RESULT IN RADIATIONAL COOLING OVERNIGHT. [DISC] NWS [National Weather Service] minor heatrisk: ∨ NWS MINOR HEATRISK: [DISC] - heat of this type is tolerated by most; however there is a minor risk for extremely heat-sensitive groups to experience negative heat-related health effects. ∨ - HEAT OF THIS TYPE IS TOLERATED BY MOST; HOWEVER THERE IS A MINOR RISK FOR EXTREMELY HEAT-SENSITIVE GROUPS TO EXPERIENCE NEGATIVE HEAT- RELATED HEALTH EFFECTS. [DISC] - the risk is primarily for those who are extremely sensitive to heat, especially when outdoors without effective cooling and/or adequate hydration. ∨ - THE RISK IS PRIMARILY FOR THOSE WHO ARE EXTREMELY SENSITIVE TO HEAT, ESPECIALLY WHEN OUTDOORS WITHOUT EFFECTIVE COOLING AND/OR ADEQUATE HYDRATION. [DISC] - very common heat. ∨ - VERY COMMON HEAT. [DISC] - for those at risk, actions that can be taken: increase hydration, reduce time spent outdoors or stay in the shade when the sun is strongest, and open windows at night and use fans to bring cooler air inside buildings. ∨ - FOR THOSE AT RISK, ACTIONS THAT CAN BE TAKEN: INCREASE HYDRATION, REDUCE TIME SPENT OUTDOORS OR STAY IN THE SHADE WHEN THE SUN IS STRONGEST, AND OPEN WINDOWS AT NIGHT AND USE FANS TO BRING COOLER AIR INSIDE BUILDINGS. [DISC] Long term. (Wednesday night through next Monday) issued at 1:11pm PDT Tuesday April 8 2025 ∨ .LONG TERM... (WEDNESDAY NIGHT THROUGH NEXT MONDAY) ISSUED AT 111 PM PDT TUE APR 8 2025 [DISC] Let's take a deep dive into the maximum temperature forecast for Wednesday and Thursday. The forecast may seem straightforward, but it's actually a lot more nuanced than one might think. For those of you that don't know, the National Weather Service (NWS [National Weather Service]) uses the national blend of models (NBM) as a starting point for building the forecast. There were multiple sites along the coast where the deterministic forecast fell below the whisker (10th percentile) of the box and whisker plot. Because of this, maximum temperatures for Wednesday and Thursday for areas that would be impacted by a 500 foot marine layer are a 50/50 blend of NBM/NBM 50th percentile. The marine layer will add even more complexity. As of now, HREF guidance does not show high probabilities of low clouds returning tonight, but if they do, expect them to primarily remain confined to the coast. If low clouds do form and end up sticking around for a prolonged amount of time, that'll certainly impact maximum temperatures. Think of a place like San Francisco. The maximum temperature of 2025 (80°) occurred on March 25th, but more importantly for this scenario is that it occurred at 1:43pm (before onshore flow kicked in). So hopefully I have painted the picture in your mind that if clouds linger in a coastal area for too long, the surface will not be able to warm as much as it would have without the clouds, thus a very boom or bust forecast at the immediate coast. Nonetheless, Wednesday will have the warmest conditions across the board thanks to the longwave ridge axis being overhead. The gradual cooldown begins Thursday as heights begin to ever so slightly fall as an upper-level shortwave trough in the Pacific Northwest nudges the ridge to the east. A surface low and its attendant weak, dry cold front will sweep through the region on Friday bringing with it an increase in northerly winds. Global ensemble cluster agreement begins to diverge Saturday, particularly in the amplitude and location of the upper-level shortwave trough. This lack in confidence gets compounded in the following days as the progression of the longwave pattern gets called into question. There's a very real possibility that an upper-level shortwave ridge will be undercut by an upper-level shortwave trough right across our region. All in all no widespread impacts aside from minor heatrisk are expected through the forecast period with no rain in sight. ∨ LET`S TAKE A DEEP DIVE INTO THE MAXIMUM TEMPERATURE FORECAST FOR WEDNESDAY AND THURSDAY. THE FORECAST MAY SEEM STRAIGHTFORWARD, BUT IT`S ACTUALLY A LOT MORE NUANCED THAN ONE MIGHT THINK. FOR THOSE OF YOU THAT DON`T KNOW, THE NATIONAL WEATHER SERVICE (NWS) USES THE NATIONAL BLEND OF MODELS (NBM) AS A STARTING POINT FOR BUILDING THE FORECAST. THERE WERE MULTIPLE SITES ALONG THE COAST WHERE THE DETERMINISTIC FORECAST FELL BELOW THE WHISKER (10TH PERCENTILE) OF THE BOX AND WHISKER PLOT. BECAUSE OF THIS, MAXIMUM TEMPERATURES FOR WEDNESDAY AND THURSDAY FOR AREAS THAT WOULD BE IMPACTED BY A 500 FOOT MARINE LAYER ARE A 50/50 BLEND OF NBM/NBM 50TH PERCENTILE. THE MARINE LAYER WILL ADD EVEN MORE COMPLEXITY. AS OF NOW, HREF GUIDANCE DOES NOT SHOW HIGH PROBABILITIES OF LOW CLOUDS RETURNING TONIGHT, BUT IF THEY DO, EXPECT THEM TO PRIMARILY REMAIN CONFINED TO THE COAST. IF LOW CLOUDS DO FORM AND END UP STICKING AROUND FOR A PROLONGED AMOUNT OF TIME, THAT`LL CERTAINLY IMPACT MAXIMUM TEMPERATURES. THINK OF A PLACE LIKE SAN FRANCISCO. THE MAXIMUM TEMPERATURE OF 2025 (80 DEGREES) OCCURRED ON MARCH 25TH, BUT MORE IMPORTANTLY FOR THIS SCENARIO IS THAT IT OCCURRED AT 1:43 PM (BEFORE ONSHORE FLOW KICKED IN). SO HOPEFULLY I HAVE PAINTED THE PICTURE IN YOUR MIND THAT IF CLOUDS LINGER IN A COASTAL AREA FOR TOO LONG, THE SURFACE WILL NOT BE ABLE TO WARM AS MUCH AS IT WOULD HAVE WITHOUT THE CLOUDS, THUS A VERY BOOM OR BUST FORECAST AT THE IMMEDIATE COAST. NONETHELESS, WEDNESDAY WILL HAVE THE WARMEST CONDITIONS ACROSS THE BOARD THANKS TO THE LONGWAVE RIDGE AXIS BEING OVERHEAD. THE GRADUAL COOLDOWN BEGINS THURSDAY AS HEIGHTS BEGIN TO EVER SO SLIGHTLY FALL AS AN UPPER-LEVEL SHORTWAVE TROUGH IN THE PACIFIC NORTHWEST NUDGES THE RIDGE TO THE EAST. A SURFACE LOW AND ITS ATTENDANT WEAK, DRY COLD FRONT WILL SWEEP THROUGH THE REGION ON FRIDAY BRINGING WITH IT AN INCREASE IN NORTHERLY WINDS. GLOBAL ENSEMBLE CLUSTER AGREEMENT BEGINS TO DIVERGE SATURDAY, PARTICULARLY IN THE AMPLITUDE AND LOCATION OF THE UPPER-LEVEL SHORTWAVE TROUGH. THIS LACK IN CONFIDENCE GETS COMPOUNDED IN THE FOLLOWING DAYS AS THE PROGRESSION OF THE LONGWAVE PATTERN GETS CALLED INTO QUESTION. THERE`S A VERY REAL POSSIBILITY THAT AN UPPER-LEVEL SHORTWAVE RIDGE WILL BE UNDERCUT BY AN UPPER-LEVEL SHORTWAVE TROUGH RIGHT ACROSS OUR REGION. ALL IN ALL NO WIDESPREAD IMPACTS ASIDE FROM MINOR HEATRISK ARE EXPECTED THROUGH THE FORECAST PERIOD WITH NO RAIN IN SIGHT. [DISC] Aviation. (06Z [11pm PDT] TAFs [Terminal Aerodrome Forecasts]) issued at 9:46pm PDT Tuesday April 8 2025 ∨ .AVIATION... (06Z TAFS) ISSUED AT 946 PM PDT TUE APR 8 2025 [AVIA] While the rest of the TAF [Terminal Aerodrome Forecast] sites stay VFR [Visual Flight Rules], haf and STS [Santa Rosa CA] will see ceilings in the late night and early morning, with some fog as well at STS [Santa Rosa CA]. Winds become weak into the night with most sites becoming variable due to more localized effects. Ceilings and fog erodes into the mid morning on Wednesday, leading to widespread VFR [Visual Flight Rules]. Moderate west winds will be slow to build into Wednesday, arriving in the late morning and afternoon. Winds reduce again that evening and into the night. Ceilings build along the coast into the early night, affecting haf, and look to slowly move inland early Thursday morning. ∨ WHILE THE REST OF THE TAF SITES STAY VFR, HAF AND STS WILL SEE CIGS IN THE LATE NIGHT AND EARLY MORNING, WITH SOME FOG AS WELL AT STS. WINDS BECOME WEAK INTO THE NIGHT WITH MOST SITES BECOMING VARIABLE DUE TO MORE LOCALIZED EFFECTS. CIGS AND FOG ERODES INTO THE MID MORNING ON WEDNESDAY, LEADING TO WIDESPREAD VFR. MODERATE WEST WINDS WILL BE SLOW TO BUILD INTO WEDNESDAY, ARRIVING IN THE LATE MORNING AND AFTERNOON. WINDS REDUCE AGAIN THAT EVENING AND INTO THE NIGHT. CIGS BUILD ALONG THE COAST INTO THE EARLY NIGHT, AFFECTING HAF, AND LOOK TO SLOWLY MOVE INLAND EARLY THURSDAY MORNING. [AVI2] Vicinity of SFO [San Francisco CA]… VFR [Visual Flight Rules] lasts through early Thursday. Winds have reduced and look to stay moderate through much of the night. These winds become light and variable for early Wednesday morning. Expect west winds to build again into Wednesday afternoon before reducing again into that night. IFR [Instrument Flight Rules] ceilings arrive into early Thursday morning along with a slight increase in westerly winds. ∨ VICINITY OF SFO...VFR LASTS THROUGH EARLY THURSDAY. WINDS HAVE REDUCED AND LOOK TO STAY MODERATE THROUGH MUCH OF THE NIGHT. THESE WINDS BECOME LIGHT AND VARIABLE FOR EARLY WEDNESDAY MORNING. EXPECT WEST WINDS TO BUILD AGAIN INTO WEDNESDAY AFTERNOON BEFORE REDUCING AGAIN INTO THAT NIGHT. IFR CIGS ARRIVE INTO EARLY THURSDAY MORNING ALONG WITH A SLIGHT INCREASE IN WESTERLY WINDS. [AVI2] SFO [San Francisco CA] bridge approach… IFR [Instrument Flight Rules] ceilings build slightly later than SFO [San Francisco CA] into Thursday morning. ∨ SFO BRIDGE APPROACH...IFR CIGS BUILD SLIGHTLY LATER THAN SFO INTO THURSDAY MORNING. [AVI2] Monterey Bay terminals… VFR [Visual Flight Rules] through the TAF [Terminal Aerodrome Forecast] period. Light winds look to last through the night and into Wednesday afternoon. Low-level cloud cover fills over the Monterey Bay itself in the late night but fails to make it over the terminals. Expect cloud cover to thin by the mid morning, with moderate westerly winds building that afternoon. These winds last into the mid to late evening before becoming light again. ∨ MONTEREY BAY TERMINALS...VFR THROUGH THE TAF PERIOD. LIGHT WINDS LOOK TO LAST THROUGH THE NIGHT AND INTO WEDNESDAY AFTERNOON. LOW- LEVEL CLOUD COVER FILLS OVER THE MONTEREY BAY ITSELF IN THE LATE NIGHT BUT FAILS TO MAKE IT OVER THE TERMINALS. EXPECT CLOUD COVER TO THIN BY THE MID MORNING, WITH MODERATE WESTERLY WINDS BUILDING THAT AFTERNOON. THESE WINDS LAST INTO THE MID TO LATE EVENING BEFORE BECOMING LIGHT AGAIN. [AVI2] Marine. (tonight through next Monday) issued at 6:11pm PDT Tuesday April 8 2025 ∨ .MARINE... (TONIGHT THROUGH NEXT MONDAY) ISSUED AT 611 PM PDT TUE APR 8 2025 [AVIA] Northerly flow will prevail over the coastal waters through the week. Winds will be locally stronger Tuesday afternoon into Wednesday south of Point Sur [Big Sur CA]. Expect a gradual improvement of the sea state as swell heights subside through midweek. A larger swell will rebuild heading into the weekend. ∨ NORTHERLY FLOW WILL PREVAIL OVER THE COASTAL WATERS THROUGH THE WEEK. WINDS WILL BE LOCALLY STRONGER TUESDAY AFTERNOON INTO WEDNESDAY SOUTH OF POINT SUR. EXPECT A GRADUAL IMPROVEMENT OF THE SEA STATE AS SWELL HEIGHTS SUBSIDE THROUGH MIDWEEK. A LARGER SWELL WILL REBUILD HEADING INTO THE WEEKEND. [AVI2] MTR Watches/Warnings/Advisories California: none. Pacific Ocean: Small Craft Advisory until 3am PDT Wednesday for Pt Pinos [Monterey CA] to Pt Piedras Blancas [San Simeon CA] 0–10 nm [11 miles]. ∨ .MTR WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...SMALL CRAFT ADVISORY UNTIL 3 AM PDT WEDNESDAY FOR PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM. [WARN] Short term…sarment long term…sarment aviation…murdock marine…MM ∨ SHORT TERM...SARMENT LONG TERM....SARMENT AVIATION...MURDOCK MARINE...MM [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 Montara CA 08 Apr 11:55am PDT Overnight Partly cloudy, with a low around 50°. NNW wind around 8 mph. Wednesday Mostly sunny, with a high near 62°. NW wind 5 to 11 mph. Wednesday Night Mostly cloudy, with a low around 50°. NW wind 6 to 10 mph. Thursday Partly sunny, with a high near 61°. NW wind 7 to 11 mph. Thursday Night Mostly cloudy, with a low around 53°. NW wind around 11 mph. Friday Mostly cloudy, with a high near 60°. Friday Night Partly cloudy, with a low around 48°. Breezy. Saturday Sunny, with a high near 58°. Breezy. Saturday Night Mostly clear, with a low around 49°. Sunday Sunny, with a high near 62°. Sunday Night Mostly clear, with a low around 49°. Monday Mostly sunny, with a high near 61°. Monday Night Mostly cloudy, with a low around 50°. Tuesday Mostly sunny, with a high near 60°. Overnight Partly cloudy, with a low around 50. North northwest wind around 8 mph. Wednesday Mostly sunny, with a high near 62. Northwest wind 5 to 11 mph. Wednesday Night Mostly cloudy, with a low around 50. Northwest wind 6 to 10 mph. Thursday Partly sunny, with a high near 61. Northwest wind 7 to 11 mph. Thursday Night Mostly cloudy, with a low around 53. Northwest wind around 11 mph. Friday Mostly cloudy, with a high near 60. Friday Night Partly cloudy, with a low around 48. Breezy. Saturday Sunny, with a high near 58. Breezy. Saturday Night Mostly clear, with a low around 49. Sunday Sunny, with a high near 62. Sunday Night Mostly clear, with a low around 49. Monday Mostly sunny, with a high near 61. Monday Night Mostly cloudy, with a low around 50. Tuesday Mostly sunny, with a high near 60.
This page is generated dynamically from the National Weather Service's NWS point forecast and Area Forecast Discussion, reformatted for readability. NWS glossary; about point forecasts. For more information, visit the Lobitos Weather Project home page. Comments and corrections are welcome: