613
FXUS66 KMTR 100901
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
201 AM PDT SUN AUG 10 2025
..NEW SHORT TERM, LONG TERM
KEY MESSAGES
UPDATED AT 200 AM PDT SUN AUG 10 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 GIVEN THE WARM AND DRY
CONDITIONS, WITH BREEZY WINDS EACH AFTERNOON AND EVENING.
- PATTERN CHANGE TUESDAY, WITH COOLER WEATHER AND COASTAL DRIZZLE
RETURNING TO THE FORECAST.
SHORT TERM
ISSUED AT 200 AM PDT SUN AUG 10 2025
(TODAY AND TONIGHT)
STARTING ANOTHER FORECAST DISCUSSION, WITH YOU GUESSED IT, SATELLITE
OBSERVATION! THE PICTURE FROM SPACE SHOWS THE STRATUS HAS SPREAD
SUBSTANTIALLY FARTHER INLAND, INFILTRATING PORTIONS OF THE NORTH,
EAST, AND SOUTH BAY REGIONS AND A GOOD PORTION OF THE CENTRAL COAST.
STRATUS WILL CONTINUE TO SNAKE IT'S WAY INTO THE REGION THIS MORNING,
BEFORE QUICKLY RETREATING BACK TO THE COAST AFTER SUNRISE. IT'S
ANOTHER, WASH, RINSE, REPEAT FORECAST! SUNNY SKIES AND SUMMER HEAT
RETURNS FOR INTERIOR LOCATIONS, AS TEMPERATURES RISE INTO THE LOW
90S TO NEAR 103. IF YOU PLAN ON BEING OUTDOORS IN THIS HEAT, WHETHER
FOR WORK OR FOR PLAY, PLEASE CONSIDER TAKING SOME HEAT SAFETY
ACTIONS. CONSIDER WEARING SUNSCREEN, TAKING BREAKS, STAYING
HYDRATED, REDUCING YOUR TIME OUTDOORS, OR WEARING LIGHTER AND/OR
LOOSER FITTED CLOTHING.
LONG TERM
ISSUED AT 200 AM PDT SUN AUG 10 2025
(MONDAY THROUGH SATURDAY)
WARMER INLAND WEATHER CONTINUES THROUGH MONDAY, WITH A PATTER CHANGE
BEGINNING ON TUESDAY. UPPER LEVEL RIDGING BREAKS DOWN AS AN UPPER
LEVEL TROUGH MOVES INTO THE PACNW. WIDESPREAD COOLING IS EXPECTED BY
WEDNESDAY AND WILL CONTINUE THROUGH FRIDAY, MODERATING SOME BY THE
WEEKEND. TROUGHING WILL LEAD TO WIDESPREAD STRATUS AND DRIZZLE
DURING THE OVERNIGHT AND EARLY MORNING HOURS.
AVIATION
(06Z TAFS)
ISSUED AT 1002 PM PDT SAT AUG 9 2025
IFR-LIFR CONDITIONS EXPECTED TONIGHT WITH DECREASES IN VISIBILITY
POSSIBLE OVERNIGHT. SOME POTENTIAL FOR FOG AT STS, HAF, MRY, AND SNS
DURING THE EARLY MORNING HOURS WITH HIGHEST CONFIDENCE IMPACTING STS
AFTER 13Z. STRATUS LOOKS TO PUSH INTO SJC LATER TONIGHT BUT IS NOT
ANTICIPATED TO REACH LVK. STRATUS COVERAGE IS EXPECTED TO DISSIPATE
BY MID TO LATE MORNING WITH VFR TO PREVAIL THROUGH THE REMAINDER OF
THE AFTERNOON. CONFIDENCE IS LOW THAT HAF WILL CLEAR BUT SOME
GUIDANCE INDICATES A BRIEF PERIOD OF CLEARING FROM ~20Z-00Z IS
POSSIBLE. IFR-LIFR CONDITIONS RETURN DURING THE EARLY EVENING ALONG
THE COASTLINE (HAF, MRY, SNS) WITH STRATUS RETURNING TO MORE
INTERIOR SITES LATER OVERNIGHT.
VICINITY OF SFO...STRATUS IS EXPECTED TO FILL IN OVERNIGHT WITH
STRATUS LIKELY TO BE ON THE IFR-LIFR BORDER. HIGHEST CONFIDENCE IN
STRATUS PERSISTING THROUGH MID TO LATE MORNING BEFORE CLOUD COVER
DIMINISHES. SOME POTENTIAL FOR STRATUS TO RETURN AS EARLY AS 09Z
TOMORROW BUT CONFIDENCE IS SLIGHTLY HIGHER IN STRATUS RETURNING JUST
AFTER THE END OF THIS TAF PERIOD. MODERATE, BREEZY NORTHWEST WINDS
RETURN DURING THE AFTERNOON/EVENING HOURS BEFORE EASING OVERNIGHT.
SFO BRIDGE APPROACH...PATCHY STRATUS IS EXPECTED TO FILL IN OVER THE
SF BAY TONIGHT AND PERSIST THROUGH MID TO LATE MORNING.
MONTEREY BAY TERMINALS...IFR-LIFR CONDITIONS OVERNIGHT AS STRATUS
PUSHES INLAND. SOME POTENTIAL FOR FOG TO DEVELOP AT MRY AND SNS
DURING THE EARLY MORNING HOURS BUT CONFIDENCE REMAINS LOW TO
MODERATE. STRATUS COVERAGE LOOKS TO DISSIPATE BETWEEN 16Z-18Z. FOR
NOW, LEANED TOWARDS STRATUS DISSIPATING CLOSER TO 18Z GIVEN MODEL
GUIDANCE AND MORE EXTENSIVE INLAND PUSH OF STRATUS BUT WORTH NOTING
THAT UNDER A PERSISTENCE FORECAST STRATUS HAS BEEN DISSIPATING
CLOSER TO 16-17Z THE LAST TWO DAYS. STRATUS RETURNS DURING THE EARLY
EVENING HOURS WITH IFR-LIFR CONDITIONS EXPECTED.
MARINE
(TONIGHT THROUGH NEXT FRIDAY)
ISSUED AT 823 PM PDT SAT AUG 9 2025
MODERATE SEAS AND A GENTLE TO MODERATE BREEZE CONTINUE THROUGH
EARLY NEXT WEEK AS HIGH PRESSURE PREVAILS ACROSS THE MARINE
ENVIRONMENT. DIURNALLY GUSTY WINDS ARE EXPECTED TO CONTINUE THIS
WEEK ACROSS THE SAN PABLO AND SUISUN BAYS WITH GUSTS TO AROUND 25
KNOTS EACH AFTERNOON AND EVENING. WINDS INCREASE AND SEAS BUILD
LATE WEEK INTO NEXT WEEKEND AS UPPER LEVEL TROUGHING RETURNS TO
THE WESTERN UNITED STATES.
FIRE WEATHER
ISSUED AT 823 PM PDT SAT AUG 9 2025
HOT AND DRY CONDITIONS CONTINUE THROUGH MONDAY, LEADING TO
ELEVATED FIRE WEATHER THREATS ACROSS THE REGION, ESPECIALLY
ACROSS THE INTERIOR MOUNTAINS WHERE OVERNIGHT HUMIDITY RECOVERIES
REMAIN POOR. THESE HOT AND DRY CONDITIONS ARE HELPING TO FURTHER
CURE FUELS (ESPECIALLY THE FINER FUELS) ACROSS THE INTERIOR
REGIONS, SHOWN BY ERC VALUES NEARING OR EXCEEDING THE 90TH
PERCENTILE. ONSHORE WINDS GUSTING TO AROUND 30-35 MPH ARE EXPECTED
TO DEVELOP EACH AFTERNOON AND EVENING THROUGH GAPS AND PASSES,
WITHIN FAVORED VALLEYS, AND ACROSS HIGHER TERRAIN. THESE FACTORS
COULD LEAD TO FIRES THAT START WITHIN THE FINER FUELS TO SPREAD
QUICKLY.
MTR WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...SMALL CRAFT ADVISORY FROM 1 PM THIS AFTERNOON TO 11 PM PDT THIS
EVENING FOR SF BAY N OF BAY BRIDGE.
SHORT TERM...KR
LONG TERM....KR
AVIATION...KENNEDY
MARINE...KENNEDY
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
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page