376
FXUS66 KSGX 131741
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
1040 AM PDT FRI MAR 13 2026
SYNOPSIS
HIGH PRESSURE WILL BRING NEAR-RECORD HEAT TO INLAND AREAS TODAY
WHILE THE COAST BEGINS TO COOL. ONSHORE FLOW ON SATURDAY WILL
BRING COOLING TO BELOW RECORD LEVELS. FOR NEXT WEEK, HIGH
PRESSURE WILL STRENGTHEN WITH WIDESPREAD RECORD HEAT FOR ALL BUT
POSSIBLY THE IMMEDIATE COAST WITH MONTHLY RECORDS FOR MARCH LIKELY
TO BE SET AT MANY LOCATIONS FOR THE VALLEYS, MOUNTAINS, AND DESERTS.
THERE WILL BE WIDESPREAD MODERATE TO LOCALLY MAJOR HEAT RISK FOR
INLAND AREAS NEXT WEEK PEAKING AROUND THURSDAY AND FRIDAY.
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
..UPDATED AVIATION, MARINE, AND BEACHES DISCUSSIONS
SHORT TERM (TODAY THROUGH FRIDAY)
WEAK OFFSHORE FLOW ON THURSDAY IS TRENDING WEAKLY ONSHORE. HIGH
TEMPERATURES FOR COASTAL AREAS ARE EXPECTED TO BE A FEW DEGREES
COOLER TODAY WITH THE DESERTS AND INLAND VALLEYS SLIGHT WARMER AND
THE MOUNTAINS AROUND 5 DEGREES WARMER. THERE COULD ONCE AGAIN BE
SEVERAL RECORD OR NEAR-RECORD HIGH TEMPERATURES TODAY, BUT MOSTLY
FOR THE VALLEYS, MOUNTAINS, AND DESERTS.
ONSHORE FLOW WILL STRENGTHEN ON SATURDAY WITH COOLING FOR MOST
AREAS. THE DESERTS WILL BE A FEW DEGREES COOLER THAN TODAY TO 8 TO
12 DEGREES COOLER FOR THE COAST AND WESTERN VALLEYS. HIGH
TEMPERATURES ON SATURDAY ARE EXPECTED TO RANGE FROM THE UPPER 60S
AND LOWER 70S NEAR THE COAST TO THE LOWER TO MID 80S FOR THE
INLAND VALLEYS WITH THE LOWER DESERTS IN THE LOWER 90S. THESE HIGH
TEMPERATURES ARE AROUND 5 DEGREES ABOVE AVERAGE NEAR THE COAST TO
10 TO 15 DEGREES ABOVE AVERAGE FOR THE INLAND VALLEYS, MOUNTAINS,
AND DESERTS, WELL-ABOVE AVERAGE BUT NOT RECORD-SETTING.
MID AND HIGH CLOUDS WILL SPREAD ACROSS THE AREA FOR LATE TODAY
THROUGH LATE SATURDAY AFTERNOON. THE LOCAL WRF IS STILL
FORECASTING A COASTAL EDDY TO DEVELOP LATE TODAY. THE MID AND HIGH
CLOUDS ARE EXPECTED TO KEEP ANY LOW CLOUDS AND FOG FOR COASTAL
AREAS FOR TONIGHT INTO SATURDAY MORNING PATCHY IN COVERAGE. THE
COASTAL EDDY CONTINUES FOR SATURDAY NIGHT INTO SUNDAY MORNING
WITH DEEPENING OF THE MARINE LAYER. GREATER COVERAGE OF LOW CLOUDS
AND FOG FOR COASTAL AREAS IS EXPECTED FOR SATURDAY NIGHT INTO
SUNDAY MORNING WITH THE DECREASE IN HIGHER LEVEL MOISTURE.
AS HIGH PRESSURE ALOFT BEGINS TO STRENGTHEN ON SUNDAY, HIGH
TEMPERATURES ARE EXPECTED TO WARM AROUND 5 DEGREES FOR THE COAST,
VALLEYS, AND COASTAL SLOPES OF THE MOUNTAINS AS THE MARINE
INVERSION BEGINS TO STRENGTHEN AND LOWER.
LONG TERM (MONDAY THROUGH THURSDAY)
HIGH PRESSURE WILL STRENGTHEN NEXT WEEK WITH THE HEAT PEAKING
AROUND THURSDAY WITH HIGH TEMPERATURES AROUND 30 DEGREES ABOVE
AVERAGE FOR THE MOUNTAINS AND INLAND VALLEYS. HIGH TEMPERATURES ON
THURSDAY WILL RANGE FROM THE LOWER TO MID 80S NEAR THE COAST TO
THE MID 90S TO 103 FOR THE INLAND VALLEYS WITH THE LOWER DESERTS
REACHING 104 TO 108. WIDESPREAD DAILY RECORD HIGH TEMPERATURES ARE
EXPECTED FOR TUESDAY THROUGH THURSDAY WITH SOME EXCEEDING THE
EXISTING MONTHLY RECORDS FOR MARCH. THERE WILL ALSO BE MANY
WARMEST OVERNIGHT TEMPERATURE RECORDS FOR THE DATE SET AS WELL.
AVIATION
131800Z...VFR CONDITIONS WITH INCREASING HIGH CLOUDS THROUGH
SATURDAY MORNING. PATCHY LOW CLOUDS AND FOG OVER THE WATERS AND
ISOLATED COASTAL AREAS 12-16Z SATURDAY. CIGS AND REDUCED VIS NOT
LIKELY AT COASTAL AIRPORTS, BUT THERE IS A SMALL (20%) CHANCE OF
BRIEF AND INTERMITTENT CLOUDS BASED AT AROUND 500 FEET MSL AND VIS
3-5SM AT KSAN.
MARINE
NO HAZARDOUS MARINE CONDITIONS ARE EXPECTED THROUGH
WEDNESDAY.
BEACHES
LINGERING LONG-PERIOD SOUTH SWELL WILL CONTINUE TO
PRODUCE A HIGH RIP CURRENT RISK AND LOCALLY HAZARDOUS SWIMMING
CONDITIONS TODAY, ESPECIALLY IN ORANGE COUNTY.
CLIMATE
THE FOLLOWING ARE THE EXISTING HIGHEST TEMPERATURE RECORDS FOR MARCH
FOR SELECTED LOCATIONS ALONG WITH THE HIGHEST DAILY NBM PROBABILITY TO
SET A NEW MARCH RECORD FOR NEXT WEEK. THIS IS NOT A COMPREHENSIVE LIST,
BUT THE MOST LIKELY LOCATIONS TO TIE OR SET NEW MONTHLY RECORD HIGH
TEMPERATURES FOR MARCH ARE IN THE DESERTS, VALLEYS, AND MOUNTAINS.
LOCATION MARCH RECORD NBM PROBABILITY
PALM SPRINGS 104 100 PERCENT (FRI)
INDIO 104 100 PERCENT (FRI,SAT)
THERMAL 103 100 PERCENT (THU,SAT)
RAMONA 94 83 PERCENT (FRI)
PALM SPRINGS NBM PROBABILITIES TO EXCEED 104 ARE 75+ PERCENT FOR WED-SAT.
INDIO NBM PROBABILITIES TO EXCEED 104 ARE 90+ PERCENT FOR WED-SAT.
THERMAL NBM PROBABILITIES TO EXCEED 103 ARE 75+ PERCENT FOR TUE-SUN.
RAMONA NBM PROBABILITIES TO EXCEED 94 ARE 75+ PERCENT ON TUE,THU,FRI.
THE EXISTING HIGHEST 500 MB HEIGHT FOR NKX FOR MARCH IS 590 DM. THAT
COULD BE EXCEEDED FOR MULTIPLE DAYS NEXT WEEK BETWEEN TUESDAY AND FRIDAY.
SKYWARN
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
SGX WATCHES/WARNINGS/ADVISORIES
CA...HEAT ADVISORY UNTIL 8 PM PDT THIS EVENING FOR ORANGE COUNTY
COASTAL AREAS-ORANGE COUNTY INLAND AREAS-SAN BERNARDINO AND
RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-SAN DIEGO COUNTY
COASTAL AREAS-SAN DIEGO COUNTY VALLEYS.
PZ...NONE.
PUBLIC/CLIMATE...17
AVIATION/MARINE...MUNYAN
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