116
FXUS66 KMTR 210817
AFDMTR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
117 AM PDT SUN JUN 21 2026
..NEW SHORT TERM, LONG TERM
KEY MESSAGES
UPDATED AT 1230 AM PDT SUN JUN 21 2026
- HAZARDOUS BEACH CONDITIONS WITH INCREASED RISK OF SNEAKER WAVES
AND STRONG RIP CURRENTS CONTINUE THROUGH THE EXTENDED FORECAST
- TEMPERATURES WILL INCREASE THROUGH THE MIDDLE OF THE WEEK
- MODERATE HEATRISK CONCERNS RETURN MIDWEEK ACROSS THE INTERIOR
SHORT TERM
ISSUED AT 1230 AM PDT SUN JUN 21 2026
(TODAY AND TONIGHT)
SATELLITE IMAGERY REVEALS STRATUS GRADUALLY EXPANDING BACK ACROSS
THE AREA EARLY THIS MORNING, ALTHOUGH IT IS LESS EXTENSIVE THAN
THE PREVIOUS COUPLE OF NIGHTS AT THIS TIME. EXPECT STRATUS TO FILL
IN ALONG THE COAST AND INLAND VALLEYS BY SUNRISE, THEN RETREAT
BACK TO THE COAST BY LATE MORNING. THE MARINE LAYER WILL COMPRESS
FURTHER TODAY AS UPPER TROUGHING ALONG THE COAST WEAKENS. THIS
SHOULD KEEP MORE CLOUDS ALONG THE COAST THIS AFTERNOON COMPARED TO
THE CLEARING EXPERIENCED SATURDAY. EXPECT WARMER TEMPERATURES IN
MOST AREAS THIS AFTERNOON, ESPECIALLY ACROSS THE INTERIOR WHICH
WILL WARM AS MUCH AS 5-10 DEGREES FROM SATURDAY. HIGHS WILL
INCREASE A FEW DEGREES ALONG SF BAY SHORELINE, WITH LITTLE CHANGE
RIGHT ALONG THE COAST. THIS WILL PLACE HIGHS IN THE UPPER 50S TO
AROUND 70 NEAR THE COAST, WITH MID 70S TO 80S IN THE INTERIOR, AND
THE WARMEST SPOTS REACHING 90 DEGREES. EXPECT TYPICAL ONSHORE
BREEZES THIS AFTERNOON AND EVENING, WITH GUSTS 15-30 MPH,
STRONGEST IN GAPS/PASSES.
THE MARINE LAYER WILL BE AROUND 1000-1500 FEET DEEP TONIGHT. THIS
WILL ALLOW LOW CLOUDS TO MOVE BACK INTO INLAND VALLEYS. THE MORE
COMPRESSED MARINE LAYER MAY ALLOW PATCHY FOG TO DEVELOP ALONG THE
COAST AND IN WIND-SHELTERED VALLEYS.
WE CONTINUE TO HIGHLIGHT A LONG-PERIOD SOUTHERLY SWELL WILL BRING
A RISK FOR SNEAKER WAVES AND STRONG RIP CURRENTS, WITH A BEACH
HAZARDS STATEMENT OUT THROUGH WEDNESDAY. IF HEADING TO THE COAST,
STAY BACK FROM THE BEACH, AND AWAY FROM JETTIES, PIERS, BEACHSIDE
ROCKS, AND OTHER INFRASTRUCTURE NEAR THE WATER. NEVER TURN YOUR
BACK TO THE OCEAN! FOR MORE INFORMATION, SEE THE BEACHES SECTION.
LONG TERM
ISSUED AT 1230 AM PDT SUN JUN 21 2026
(MONDAY THROUGH SATURDAY)
A BUILDING UPPER LEVEL RIDGE WILL KEEP THE MARINE LAYER COMPRESSED
AND CONTINUE A WARMING TREND THROUGH THE MIDDLE OF THE WEEK.
HIGHS WILL WARM A FEW DEGREES EACH DAY, REACHING THEIR PEAK ON
WEDNESDAY. HOWEVER, HIGHS TUESDAY AND THURSDAY WILL ALSO BE QUITE
WARM AND WITHIN A COUPLE DEGREES OF WEDNESDAY'S READINGS. MARINE
INFLUENCE SHOULD LIMIT WARMING ALONG THE COAST AND BAYS WITH HIGHS
IN THE 60S AND 70S, BUT THIS WILL STILL BE SEVERAL DEGREES WARMER
THAN TODAY. ACROSS THE INTERIOR, HIGHS WILL REACH THE 80S AND
90S. HOT TEMPERATURES, ESPECIALLY INLAND, WILL BE ACCOMPANIED BY
POCKETS OF MODERATE HEATRISK WITH INCREASED HEAT IMPACTS. THE
TREND STILL HOLDS FROM THE PREVIOUS DISCUSSION THAT COVERAGE OF
MODERATE HEATRISK LOOKS TOO LIMITED FOR A HEAT ADVISORY. HOWEVER,
HOT TEMPERATURES MAY PRODUCE A RISK FOR HEAT-RELATED ILLNESSES
AMONGST SENSITIVE POPULATIONS, INCLUDING CHILDREN, THE ELDERLY,
PREGNANT WOMEN, PEOPLE WITH CHRONIC ILLNESSES, AND PEOPLE WHO WORK
OR LIVE OUTDOORS WITHOUT ACCESS TO ADEQUATE COOLING OR HYDRATION.
LATEST ENSEMBLE GUIDANCE CONTINUES THE TREND OF KEEPING
MOISTURE/INSTABILITY ROTATING AROUND THE RIDGE TO OUR EAST. THIS
MEANS THUNDERSTORMS NEXT WEEK ARE HIGHLY UNLIKELY, BUT ANY
POTENTIAL WILL CONTINUE TO BE MONITORED. LATE THIS WEEK,
TEMPERATURES TREND COOLER AS AN UPPER TROUGH MOVES INTO THE
PACIFIC NORTHWEST. IT WILL REMAIN DRY IN OUR AREA, BUT WINDS MAY
BECOME BREEZY AS THIS SYSTEM MOVES BY TO THE NORTH.
AVIATION
(06Z TAFS)
ISSUED AT 852 PM PDT SAT JUN 20 2026
VFR CONDITIONS PREVAIL DUE TO CARRYOVER MIXING WITHIN THE BOUNDARY
LAYER FROM EARLIER IN THE DAY. A SHALLOW COOL FRONT WILL MOVE
SOUTHEASTWARD ALONG THE CA COAST, COMBINING WITH POST SUNSET
RADIATIVE COOLING THIS WILL BRING A RETURN OF STRATUS /MVFR-IFR/
TONIGHT AND SUNDAY MORNING. THERMAL RIDGING WILL PERSIST ALOFT
DURING THE PERIOD. PATCHY LIGHT COASTAL DRIZZLE IS POSSIBLE
TONIGHT AND SUNDAY MORNING. COASTAL STRATUS MIXES OUT TO MVFR-VFR
LATE SUNDAY MORNING AND AFTERNOON. COASTAL STRATUS REDEVELOPS
SUNDAY NIGHT AND MONDAY MORNING.
VICINITY OF SFO...STRATUS /MVFR/ IS FORECAST TO RETURN TO THE
TERMINAL. STRATUS /MVFR/ AND TEMPO LIGHT DRIZZLE TONIGHT AND
SUNDAY MORNING. CONDITIONS IMPROVE TO VFR BY 18Z SUNDAY. STRATUS
/MVFR/ RETURNS BY MID SUNDAY EVENING. WEST WIND 11 TO 18 KNOTS
DUE TO THE INCOMING COOL FRONT TONIGHT. WEST WIND 15 TO 25 KNOTS
REDEVELOPING BY 21Z SUNDAY AFTERNOON, EASING TO NEAR 10 KNOTS MID
SUNDAY EVENING.
SFO BRIDGE APPROACH...SIMILAR TO SFO.
VICINITY OF SJC AND OAK...FOR SJC AIRPORT VFR FOR THE EVENING,
STRATUS /MVFR/ RETURNS BY 10Z THEN MIXES OUT TO VFR BY 18Z SUNDAY.
NORTHWEST WIND 10 KNOTS TONIGHT BECOMING LIGHT SOUTHEASTERLY SUNDAY
MORNING. NORTHWEST WIND REDEVELOPING SUNDAY AFTERNOON. FOR OAK
AIRPORT STRATUS /MVFR/ PREVAILS TONIGHT AND SUNDAY MORNING, MIXING
OUT TO VFR BY 18Z. ALSO, TEMPO LIGHT DRIZZLE 11Z-15Z SUNDAY. WEST
WIND 5 TO 15 KNOTS.
MONTEREY BAY TERMINALS...STRATUS /MVFR/ RETURNS THIS EVENING,
STRATUS PREVAILS WITH TEMPO LIGHT DRIZZLE TONIGHT AND SUNDAY
MORNING. CONDITIONS IMPROVING TO VFR LATE SUNDAY MORNING AND
AFTERNOON. STRATUS /MVFR-IFR/ RETURNS SUNDAY EVENING AND NIGHT.
ONSHORE WINDS 5 TO 15 KNOTS.
MARINE
(TONIGHT THROUGH NEXT FRIDAY)
ISSUED AT 843 PM PDT SAT JUN 20 2026
FRESH TO STRONG WINDS IN THE NORTHERN OUTER WATERS NOW THROUGH
EARLY MONDAY MORNING, LEADING TO HAZARDOUS CONDITIONS FOR SMALL
CRAFT. OTHERWISE, ACROSS THE INNER AND OUTER WATERS WINDS WILL
REMAIN LIGHT TO MODERATE. LONG PERIOD SOUTHWEST SWELL CONTINUES
THROUGH THE FORECAST PERIOD.
BEACHES
ISSUED AT 308 AM PDT SAT JUN 20 2026
LONG PERIOD SOUTHERLY SWELL AT AROUND 15 TO 17 SECONDS WILL
PERSIST FOR THE REMAINDER OF THE WEEKEND, AND INCREASE TO 17 TO
19 SECONDS BY THE MIDDLE OF THE UPCOMING WORK WEEK AS ENERGETIC
STORMS IN THE SOUTHERN HEMISPHERE CONTINUE TO AFFECT THE
CALIFORNIA COAST, ESPECIALLY FOR SOUTH AND SOUTHWEST FACING
BEACHES. HAZARDOUS BEACH CONDITIONS ARE ADVERTISED, SPECIFICALLY
FOR MODERATE TO STEEPLY SLOPED BEACHES ALONG THE PACIFIC COAST OF
THE NORTH BAY, SAN MATEO, SANTA CRUZ COUNTIES. A BEACH HAZARDS
STATEMENT FOR PACIFIC COAST BEACHES CONTINUES THROUGH WEDNESDAY
AFTERNOON. BE SURE TO CHECK BEACH CONDITIONS BEFORE YOU HEAD OUT.
SNEAKER WAVES WILL RUN UP THE BEACH MUCH FARTHER THAN OTHER
WAVES, POTENTIALLY CATCHING BEACHGOERS BY SURPRISE AND RESULTING
IN PEOPLE BEING SWEPT INTO THE WATER. RIP CURRENTS ARE STRONG
ENOUGH TO PULL THE STRONGEST SWIMMERS AWAY FROM SHORE. SWIM NEAR A
LIFEGUARD IF POSSIBLE. STAY BACK FROM THE BEACH, AND AWAY FROM
JETTIES, PIERS, BEACHSIDE ROCKS, AND OTHER INFRASTRUCTURE NEAR THE
WATER. NEVER TURN YOUR BACK TO THE OCEAN!
MTR WATCHES/WARNINGS/ADVISORIES
CA...BEACH HAZARDS STATEMENT THROUGH WEDNESDAY AFTERNOON FOR CAZ006-
505-509-529-530.
PZ...SMALL CRAFT ADVISORY UNTIL 3 AM PDT MONDAY FOR PT ARENA TO PT
REYES 10-60 NM.
SHORT TERM...TANGEN
LONG TERM....TANGEN
AVIATION...CANEPA
MARINE...MALARKEY
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