Area Forecast Discussion
FXUS66 KMTR [Monterey CA] 091715 AFDMTR ∨
FXUS66 KMTR 091715 AFDMTR [HEAD]
National Weather Service San Francisco California 9:15am PST Sat Dec 9 2023 ∨
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN FRANCISCO CA 915 AM PST SAT DEC 9 2023 [HEAD]
New update. ∨
...NEW UPDATE... [DISC]
Synopsis. Issued at 12:23am PST Sat December 9 2023 ∨
.SYNOPSIS... ISSUED AT 1223 AM PST SAT DEC 9 2023 [DISC]
High pressure will bring quiet weather over the next several days. Cold overnights and interior frost/freezing conditions are expected this weekend before a gradual warming trend occurs early next week. ∨
HIGH PRESSURE WILL BRING QUIET WEATHER OVER THE NEXT SEVERAL DAYS. COLD OVERNIGHTS AND INTERIOR FROST/FREEZING CONDITIONS ARE EXPECTED THIS WEEKEND BEFORE A GRADUAL WARMING TREND OCCURS EARLY NEXT WEEK. [DISC]
Update. Issued at 9:15am PST Sat December 9 2023 ∨
.UPDATE... ISSUED AT 915 AM PST SAT DEC 9 2023 [DISC]
To start the weekend, upper level ridging is nosing in from the SW. A few high clouds are riding the periphery of the ridge this morning, but for the most part sunny skies to start the day. Despite a few clouds overhead this morning conditions were good enough for some radiational cooling. Interior portions of the North Bay valleys and interior Monterey/San Benito are currently under a Freeze Warning and also the coldest locations. A few spots in the Salinas Valley reached the mid to upper 20s. Bradley for instance hit 25° this morning. While other areas were not in a frost/freeze product it was still chilly. Even a few coastal locations hits the mid to upper 30s. No updated needed this morning. ∨
TO START THE WEEKEND, UPPER LEVEL RIDGING IS NOSING IN FROM THE SW. A FEW HIGH CLOUDS ARE RIDING THE PERIPHERY OF THE RIDGE THIS MORNING, BUT FOR THE MOST PART SUNNY SKIES TO START THE DAY. DESPITE A FEW CLOUDS OVERHEAD THIS MORNING CONDITIONS WERE GOOD ENOUGH FOR SOME RADIATIONAL COOLING. INTERIOR PORTIONS OF THE NORTH BAY VALLEYS AND INTERIOR MONTEREY/SAN BENITO ARE CURRENTLY UNDER A FREEZE WARNING AND ALSO THE COLDEST LOCATIONS. A FEW SPOTS IN THE SALINAS VALLEY REACHED THE MID TO UPPER 20S. BRADLEY FOR INSTANCE HIT 25 DEGREES THIS MORNING. WHILE OTHER AREAS WERE NOT IN A FROST/FREEZE PRODUCT IT WAS STILL CHILLY. EVEN A FEW COASTAL LOCATIONS HITS THE MID TO UPPER 30S. NO UPDATED NEEDED THIS MORNING... [DISC]
After the chilly start today will be a mild and in the 60s. ∨
AFTER THE CHILLY START TODAY WILL BE A MILD AND IN THE 60S. [DISC]
Short term. (today and tonight) issued at 12:23am PST Sat December 9 2023 ∨
.SHORT TERM... (TODAY AND TONIGHT) ISSUED AT 1223 AM PST SAT DEC 9 2023 [DISC]
The storm track will be diverted well to our north as high pressure aloft noses into our area from the southwest. This will support surface ridging as it expands to encompass the Great Basin and provide a light offshore wind regime to the area. After a cold and frosty (for some) start this morning look for temperatures to reach the lower to mid 60s across the region today with plenty of sunshine. Tonight will be cool, but not quite as cold as the previous nights have been. That said, the coldest portions of the inland Central Coast and North Bay valleys will still see temperatures at or below 35° or so. Therefore the Freeze Watch was converted to a Frost Advisory for these areas from late tonight into Sunday morning. Remember to protect people, pets, plants and pipes from the cold. ∨
THE STORM TRACK WILL BE DIVERTED WELL TO OUR NORTH AS HIGH PRESSURE ALOFT NOSES INTO OUR AREA FROM THE SOUTHWEST. THIS WILL SUPPORT SURFACE RIDGING AS IT EXPANDS TO ENCOMPASS THE GREAT BASIN AND PROVIDE A LIGHT OFFSHORE WIND REGIME TO THE AREA. AFTER A COLD AND FROSTY (FOR SOME) START THIS MORNING LOOK FOR TEMPERATURES TO REACH THE LOWER TO MID 60S ACROSS THE REGION TODAY WITH PLENTY OF SUNSHINE. TONIGHT WILL BE COOL, BUT NOT QUITE AS COLD AS THE PREVIOUS NIGHTS HAVE BEEN. THAT SAID, THE COLDEST PORTIONS OF THE INLAND CENTRAL COAST AND NORTH BAY VALLEYS WILL STILL SEE TEMPERATURES AT OR BELOW 35 DEGREES OR SO. THEREFORE THE FREEZE WATCH WAS CONVERTED TO A FROST ADVISORY FOR THESE AREAS FROM LATE TONIGHT INTO SUNDAY MORNING. REMEMBER TO PROTECT PEOPLE, PETS, PLANTS AND PIPES FROM THE COLD. [DISC]
Long term. (Sunday through Friday) issued at 12:23am PST Sat December 9 2023 ∨
.LONG TERM... (SUNDAY THROUGH FRIDAY) ISSUED AT 1223 AM PST SAT DEC 9 2023 [DISC]
Relatively quiet weather will prevail for the remainder of the week with gradually warming daytime temperatures. Overnight readings will remain cool however with the coldest interior locations dipping into the upper 30s and 40s. Daytime highs will be mostly in the 60s. ∨
RELATIVELY QUIET WEATHER WILL PREVAIL FOR THE REMAINDER OF THE WEEK WITH GRADUALLY WARMING DAYTIME TEMPERATURES. OVERNIGHT READINGS WILL REMAIN COOL HOWEVER WITH THE COLDEST INTERIOR LOCATIONS DIPPING INTO THE UPPER 30S AND 40S. DAYTIME HIGHS WILL BE MOSTLY IN THE 60S. [DISC]
Looking ahead deterministic models and their ensembles suggest a more unsettled pattern developing around December 16th-18th. Still some fine tuning of the details but it does appear that rain will re-enter the forecast picture around this time. ∨
LOOKING AHEAD DETERMINISTIC MODELS AND THEIR ENSEMBLES SUGGEST A MORE UNSETTLED PATTERN DEVELOPING AROUND DECEMBER 16TH-18TH. STILL SOME FINE TUNING OF THE DETAILS BUT IT DOES APPEAR THAT RAIN WILL RE- ENTER THE FORECAST PICTURE AROUND THIS TIME. [DISC]
Aviation. (12Z [4am PST] TAFs [Terminal Aerodrome Forecasts]) issued at 3:29am PST Sat December 9 2023 ∨
.AVIATION... (12Z TAFS) ISSUED AT 329 AM PST SAT DEC 9 2023 [AVIA]
High pressure dominates the pattern. The terminals will remain mostly VFR [Visual Flight Rules] with few to scattered high clouds and light to gentle winds through the day. The only exception is STS [Santa Rosa CA], where some morning mist/fog will reduce the visibility to MVFR [Marginal Visual Flight Rules]/IFR [Instrument Flight Rules]. It's also worth noting that the temperature is approaching freezing and some aircraft icing is expected before the mist/fog clears after sunrise. There is also a low to moderate chance for dense fog and LIFR [Low Instrument Flight Rules] conditions to develop at STS [Santa Rosa CA] later this morning. ∨
HIGH PRESSURE DOMINATES THE PATTERN. THE TERMINALS WILL REMAIN MOSTLY VFR WITH FEW TO SCATTERED HIGH CLOUDS AND LIGHT TO GENTLE WINDS THROUGH THE DAY. THE ONLY EXCEPTION IS STS, WHERE SOME MORNING MIST/FOG WILL REDUCE THE VISIBILITY TO MVFR/IFR. IT`S ALSO WORTH NOTING THAT THE TEMPERATURE IS APPROACHING FREEZING AND SOME AIRCRAFT ICING IS EXPECTED BEFORE THE MIST/FOG CLEARS AFTER SUNRISE. THERE IS ALSO A LOW TO MODERATE CHANCE FOR DENSE FOG AND LIFR CONDITIONS TO DEVELOP AT STS LATER THIS MORNING. [AVI2]
Vicinity of SFO [San Francisco CA]… VFR [Visual Flight Rules] through the TAF [Terminal Aerodrome Forecast] period. Light winds may shift erratically with no discernible steering flow through mid day. A gentle NW sea breeze will develop in the afternoon before winds return to light and variable Saturday night. ∨
VICINITY OF SFO...VFR THROUGH THE TAF PERIOD. LIGHT WINDS MAY SHIFT ERRATICALLY WITH NO DISCERNIBLE STEERING FLOW THROUGH MID DAY. A GENTLE NW SEA BREEZE WILL DEVELOP IN THE AFTERNOON BEFORE WINDS RETURN TO LIGHT AND VARIABLE SAT NIGHT. [AVI2]
SFO [San Francisco CA] bridge approach… similar to SFO [San Francisco CA]. ∨
SFO BRIDGE APPROACH... SIMILAR TO SFO. [AVI2]
Monterey Bay terminals… VFR [Visual Flight Rules] through the TAF [Terminal Aerodrome Forecast] period. Light drainage flow this morning before onshore flow resumes in the afternoon. ∨
MONTEREY BAY TERMINALS... VFR THROUGH THE TAF PERIOD. LIGHT DRAINAGE FLOW THIS MORNING BEFORE ONSHORE FLOW RESUMES IN THE AFTERNOON. [AVI2]
Marine. (tonight through next Wednesday) issued at 3:01am PST Sat December 9 2023 ∨
.MARINE... (TONIGHT THROUGH NEXT WEDNESDAY) ISSUED AT 301 AM PST SAT DEC 9 2023 [AVIA]
High pressure will bring quiet and dry conditions to the region. Light to moderate northerly breezes persist through the weekend with diminishing seas. Fresh to strong breezes return to the offshore waters by early to mid next week. ∨
HIGH PRESSURE WILL BRING QUIET AND DRY CONDITIONS TO THE REGION. LIGHT TO MODERATE NORTHERLY BREEZES PERSIST THROUGH THE WEEKEND WITH DIMINISHING SEAS. FRESH TO STRONG BREEZES RETURN TO THE OFFSHORE WATERS BY EARLY TO MID NEXT WEEK. [AVI2]
.MTR WATCHES/WARNINGS/ADVISORIES... CA...FREEZE WARNING UNTIL 10 AM PST THIS MORNING FOR CAZ506-516-518. [WARN]
FROST ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM PST SUNDAY FOR CAZ506-516-518. [WRN2]
SHORT TERM...SPM LONG TERM....SPM AVIATION...FLYNN MARINE...SPM [WRN2]
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Half Moon Bay Airport
09 Dec 09:15am PST
Today Mostly sunny, with a high near 60°. North wind around 8 mph.
Tonight Partly cloudy, with a low around 40°. NE wind around 6 mph.
Sunday Partly sunny, with a high near 60°. NE wind 6 to 8 mph.
Sunday Night Mostly cloudy, with a low around 45°. NNW wind around 7 mph.
Monday Partly sunny, with a high near 60°. NW wind 6 to 9 mph.
Monday Night Mostly cloudy, with a low around 46°.
Tuesday Mostly sunny, with a high near 60°.
Tuesday Night Partly cloudy, with a low around 44°.
Wednesday Mostly sunny, with a high near 60°.
Wednesday Night Mostly cloudy, with a low around 45°.
Thursday Partly sunny, with a high near 61°.
Thursday Night Mostly cloudy, with a low around 44°.
Friday Mostly sunny, with a high near 62°.
Mostly sunny, with a high near 60. North wind around 8 mph.
Partly cloudy, with a low around 40. Northeast wind around 6 mph.
Partly sunny, with a high near 60. Northeast wind 6 to 8 mph.
Mostly cloudy, with a low around 45. North northwest wind around 7 mph.
Partly sunny, with a high near 60. Northwest wind 6 to 9 mph.
Mostly cloudy, with a low around 46.
Mostly sunny, with a high near 60.
Partly cloudy, with a low around 44.
Mostly sunny, with a high near 60.
Mostly cloudy, with a low around 45.
Partly sunny, with a high near 61.
Mostly cloudy, with a low around 44.
Mostly sunny, with a high near 62.