667
FXUS66 KMTR 111614
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
914 AM PDT MON AUG 11 2025
..NEW UPDATE
KEY MESSAGES
UPDATED AT 333 AM PDT MON AUG 11 2025
- MODERATE HEATRISK CONTINUES THROUGH MONDAY FOR PORTIONS OF NORTH,
EAST, AND SOUTH BAY COUNTIES AND INTERIOR MONTEREY AND SAN
BENITO COUNTIES.
- ELEVATED FIRE WEATHER CONCERNS PERSIST THROUGH MONDAY GIVEN THE WARM
AND DRY CONDITIONS COMBINED WITH BREEZY AFTERNOON AND EVENING
WINDS.
- PATTERN CHANGE TUESDAY, WITH COOLER WEATHER AND COASTAL DRIZZLE
RETURNING TO THE FORECAST.
UPDATE
ISSUED AT 850 AM PDT MON AUG 11 2025
MARINE LAYER RAMPED UP SLIGHTLY THIS MORNING. AS SUCH, BETTER
COVERAGE OF CLOUDS ACROSS THE INLAND VALLEYS, LESS DENSE FOG BEING
REPORTED, STILL SOME FOG BUT IN THE 3-6 MILE RANGE, AND LESS
DRIZZLE. SOUTHERLY TRANSPORT FLOW DID ALLOW FOR SOME UPPER LEVEL
SMOKE FROM THE GIFFORD FIRE TO SNEAK INTO THE FORECAST AREA.
THANKFULLY, THIS IS MAINLY HIGH LEVEL SMOKE. LATEST SMOKE
GUIDANCE SHOWS A SHIFT IN TRANSPORT FLOW SO WILL PUSH SOME OF THE
SMOKE SOUTHWARD AGAIN.
NO UPDATE NEEDED.
ONE MORE DAY OF INLAND HEAT. DETAILS BELOW...
STILL WAITING FOR ALL LATEST GUIDANCE TO COME, BUT WILL BE DOING A
DEEPER DIVE INTO IVO MOISTURE AND POTENTIAL IMPACTS. IVO DETAILS
FROM BEFORE DOWN BELOW...
SHORT TERM
ISSUED AT 333 AM PDT MON AUG 11 2025
(TODAY AND TONIGHT)
THE FORT ORD PROFILER THIS MORNING SHOWS THE MARINE LAYER AROUND
1400FT THIS MORNING, WITH THE SPREAD OF THE STRATUS LOOKING TO MATCH
A MARINE LAYER DEPTH OF 1500FT. STRATUS SHOULD TAKE A TOUCH LONGER
TO ERODE THIS MORNING, ESPECIALLY FOR THOSE CLOSER TO THE COAST.
OVERALL, ANOTHER SUNNY DAY IS EXPECTED FOR INTERIOR LOCATIONS WITH
HIGH TEMPERATURES PEAKING 90S, PERHAPS CLOSER TO THE UPPER 90S TO
NEAR 105 FOR INTERIOR CONTRA COSTA, SAN BENITIO, AND MONTEREY
COUNTIES. STRATUS RETURNS TONIGHT AND WILL SEEP INTO THE VALLEYS
LONG TERM
ISSUED AT 333 AM PDT MON AUG 11 2025
(TUESDAY THROUGH SUNDAY)
THE PATTERN CHANGE BEGINS ON TUESDAY, THOUGH BE IT, PERHAPS A BIT
MORE MINIMALLY THAN PREVIOUSLY EXPECTED. A SHORTWAVE TROUGH
APPROACHES THE PACNW WHICH WILL BEGIN TO FLATTEN THE UPPER LEVEL
RIDGE. HIGH TEMPERATURES WILL BE A FEW DEGREES COOLER THAN MONDAY,
WITH THE GRADUAL DECREASE IN TEMPERATURES CONTINUING THROUGHOUT THE
WEEK. THE MORE SUBSTANTIAL TROUGH, KICKS IN ON WEDNESDAY WHICH WILL
PAVE THE WAY FOR UPPER LEVEL TROUGHING TO DOMINATE THE FORECAST
THROUGH THE WEEKEND. LOOK FOR CLOUDY, DRIZZLY, AND FOGGY OVERNIGHTS
AND SUNNY SKIES FOR INTERIOR LOCATIONS BY THE AFTERNOON.
AN INTERESTING NOTE IN THE FORECAST IS THAT A FEW DETERMINISTIC
MODELS ARE TRYING TO SHOW MOISTURE FROM TROPICAL DEPRESSION IVO
BEING PULLED OVER OUR COAST. CAPE SEEMS TO STRUGGLE TO MANIFEST
GIVEN THE TROUGHING, BUT MIDLEVEL LAPSE RATES ARE INTERESTING AROUND
7.5-8C/KM. FOR NOW CURRENT THINKING IS PERHAPS WE SEE SOME CUMULUS
CLOUDS OR PERHAPS SOME HIGH LEVEL CLOUDS. THUNDERSTORM DEVELOPMENT
LOOKS UNLIKELY AT THIS TIME.
AVIATION
(12Z TAFS)
ISSUED AT 358 AM PDT MON AUG 11 2025
CURRENTLY A MIXED BAG OF IFR-VFR AT THE TERMINALS WITH A MARINE
LAYER OF ABOUT 1,600 FEET. HIGH (80%) CONFIDENCE IN WIDESPREAD VFR
THIS AFTERNOON WITH LOW STRATUS STICKING CLOSE TO THE COAST. LITTLE
CHANGE IN THE OVERALL PATTERN WILL YIELD SIMILAR CONDITIONS TONIGHT
AS WHAT IS CURRENTLY UNDERWAY.
VICINITY OF SFO...CURRENTLY IFR WITH WESTERLY FLOW. HIGH (90%)
CONFIDENCE IN VFR BY THE AFTERNOON WITH MODERATE (60%) CONFIDENCE ON
AN IFR CEILING RETURNING TO THE TERMINAL TONIGHT. WESTERLY WINDS
WILL PREVAIL THROUGH THE TAF PERIOD.
SFO BRIDGE APPROACH...SIMILAR TO SFO.
MONTEREY BAY TERMINALS...CURRENTLY IFR WITH NORTHWESTERLY FLOW AT
BOTH TERMINALS. HIGH (80%) CONFIDENCE ON BRIEF VFR BEING ACHIEVED
WITH MODERATE (50-60%) CONFIDENCE ON IFR CEILINGS RETURNING TO
BOTH TERMINALS TONIGHT.
MARINE
(TODAY THROUGH SATURDAY)
ISSUED AT 333 AM PDT MON AUG 11 2025
MODERATE SEAS WILL BUILD TO BECOME ROUGH FOR INNER WATERS AND
OUTER WATERS THURSDAY. NORTHWESTERLY BREEZES WILL BE GENTLE TO
MODERATE THROUGH WEDNESDAY WITH DIURNALLY DRIVEN AFTERNOON SEA
BREEZES BRINGING LOCALIZED STRONG GUSTS THROUGH THE DELTA AND
ALONG POINT SUR. NORTHWESTERLY BREEZES INCREASE THURSDAY TO
BECOME FRESH TO STRONG, POSING HAZARDOUS CONDITIONS FOR SMALL
CRAFT.
FIRE WEATHER
ISSUED AT 908 AM PDT MON AUG 11 2025
ANOTHER NIGHT WITH POOR HUMIDITY RECOVERY ABOVE THE MARINE LAYER.
MAY SITES IN THE 15-20% RANGE. THIS IS ROUGHLY 5-7 DAYS OF THE
PATTERN SO THE HILLS ARE CRISPY. THANKFULLY, THE OVERALL FIRE
WEATHER CONCERNS THE NEXT FEW DAYS WILL BE EASING AS INTERIOR
HEAT BREAKS AND HUMIDITY BEGINS TO CREEP UPWARD. WHILE THE ERC HAD
BEEN CLIMBING AND THE FUEL MOISTURE HAD BEEN DROPPING THE 7 DAY
FORECAST SHOWS A REVERSE WITH DROPPING ERC AND RISING FUEL
MOISTURE.
MTR WATCHES/WARNINGS/ADVISORIES
CA...BEACH HAZARDS STATEMENT THROUGH TUESDAY EVENING FOR CAZ505-529.
PZ...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 11 PM PDT THIS
EVENING FOR SF BAY N OF BAY BRIDGE.
SMALL CRAFT ADVISORY FROM 1 PM TO 9 PM PDT TUESDAY FOR SF BAY N
OF BAY BRIDGE.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 3 AM PDT
WEDNESDAY FOR PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM.
SHORT TERM...KR
LONG TERM....KR
AVIATION...SARMENT
MARINE...SARMENT
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