865
FXUS66 KSGX 271015
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
315 AM PDT THU MAR 27 2025
SYNOPSIS
COOL WITH A DEEP MARINE AND PATCHY DRIZZLE AT TIMES THROUGH THE
WEEKEND. THERE WILL BE GUSTY WEST WINDS FOR THIS AFTERNOON
THROUGH FRIDAY NIGHT WITH THE STRONGER GUSTS FOR THE MOUNTAINS
AND DESERTS MOSTLY 40 TO 50 MPH. COOLER THAN AVERAGE CONDITIONS
WILL CONTINUE INTO NEXT WEEK WITH CHANCES FOR PRECIPITATION
INCREASING TO AROUND 50 PERCENT FOR NEXT WEDNESDAY AND THURSDAY.
CONFIDENCE IS LOWER WITH THE TIMING AND POTENTIAL AMOUNTS. DAILY
CHANCES FOR ONE INCH OR MORE OF RAINFALL ARE 25 PERCENT OR LESS
FOR THE TYPICALLY WETTER LOCATIONS ON THE COASTAL SLOPES OF THE
MOUNTAINS.
DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
SHORT TERM (TODAY THROUGH SATURDAY)
SATELLITE IMAGERY SHOWS THE MARINE LAYER IS AROUND 3500 TO 4000
FEET DEEP EARLY THIS MORNING, BUT WITH SURFACE REPORTS SHOWING
CLOUD BASES AROUND 3000 FEET WITH A MUCH REDUCED DEPTH TO THE
SATURATED CLOUD LAYER VERSUS 24 HOURS AGO. WHILE THERE COULD BE
SOME PATCHY DRIZZLE EARLY THIS MORNING, IT IS EXPECTED TO BE MUCH
LESS THAN ON WEDNESDAY MORNING. THE NAM CHANCES FOR MEASURABLE
PRECIPITATION FOR THE COAST INTO THE VALLEYS ARE GREATER AGAIN FOR
LATE TONIGHT INTO FRIDAY MORNING AND AGAIN FOR LATE FRIDAY NIGHT
INTO SATURDAY MORNING WITH DRIZZLE IN THE FORECAST FOR PORTIONS OF
THE COAST, VALLEYS, AND COASTAL WATERS FOR THOSE TIMES.
LITTLE CHANGE IS EXPECTED WITH HIGH TEMPERATURES FOR THE COAST AND
VALLEYS THROUGH THE WEEKEND WITH COOLING FOR THE DESERTS FOR TODAY
AND FRIDAY FOLLOWED BY LITTLE CHANGE FOR THE WEEKEND. THERE WILL
BE STRONGER ONSHORE FLOW THROUGH FRIDAY NIGHT WITH AREAS OF
STRONGER AND GUSTY WEST WINDS FOR THIS AFTERNOON THROUGH FRIDAY.
THE STRONGER WINDS ARE EXPECTED IN THE MOUNTAINS AND DESERTS WITH
THE STRONGER GUSTS ALONG AND BELOW THE DESERT SLOPES OF THE
MOUNTAINS TO 40 TO 50 MPH.
LONG TERM (SUNDAY THROUGH WEDNESDAY)
NOT MUCH CHANGE FOR SUNDAY. THERE MAY BE SLIGHT WARMING ON MONDAY
AND SLIGHT COOLING ON TUESDAY. PRECIPITATION FROM A LOW PRESSURE
SYSTEM CENTERED OFF THE PACIFIC NORTHWEST COAST WILL MOSTLY REMAIN
NORTH OF THE AREA FOR MONDAY AND TUESDAY WITH NBM DAILY CHANCES
FOR MEASURABLE PRECIPITATION LESS THAN 20 PERCENT.
FOR WEDNESDAY THROUGH SATURDAY OF NEXT WEEK, THERE REMAIN GREATER
DIFFERENCES AMONG MODEL ENSEMBLE MEMBERS IN THE TIMING AND
LOCATION OF LOW PRESSURE SYSTEMS MOVING ACROSS THE EASTERN PACIFIC
INTO THE WESTERN STATES WITH LOWER CONFIDENCE IN THE DETAILS OF
THE FORECAST FOR SOUTHWESTERN CALIFORNIA FOR NEXT WEDNESDAY AND
THURSDAY. THE DETERMINISTIC NBM FOR HIGH TEMPERATURES SHOWS SLIGHT
COOLING ON WEDNESDAY WITH A FEW MORE DEGREES OF COOLING FOR
THURSDAY, THOUGH WITH GREATER SPREAD IN THE GUIDANCE FOR BOTH
DAYS.
NBM DAILY CHANCES FOR MEASURABLE PRECIPITATION INCREASE TO 40 TO
50 PERCENT FOR WEDNESDAY AND 50 TO 60 PERCENT THURSDAY OF NEXT
WEEK, BUT WITH DAILY CHANCES FOR ONE INCH OR MORE OF RAINFALL 25
PERCENT OR LESS ON THE TYPICALLY WETTER LOCATIONS ON THE COASTAL
SLOPES OF THE MOUNTAINS.
AVIATION
271000Z...COAST/VALLEYS/FOOTHILLS...LOW CLOUDS PERSIST ACROSS THE
COASTAL BASIN. BASES VARY BETWEEN 2500-3500 FEET MSL WITH TOPS TO
4500 FEET, BUT ARE EXPECTED TO LOWER BELOW 3000 FT MSL 12-14Z THIS
MORNING. VIS REDUCED 3-5SM OVER HIGHER TERRAIN INLAND, WITH PARTIAL
OBSCURATIONS OF 0-2SM IN FOOTHILLS. PARTIAL SCATTER OUT AFTER 18Z,
ESPECIALLY FOR COASTAL AREAS. LOW CLOUDS START FILLING IN THE
COASTAL BASIN AFTER 00Z FRIDAY, BECOMING WIDESPREAD AFTER 02-04Z.
BASES 2000-3000 FT MSL.
HIGHER MOUNTAINS/DESERTS...SCT HIGH CLOUDS ABOVE 20000 FEET MSL.
WESTERLY WINDS OVER THE RIDGES STRENGTHEN AND SPREAD THROUGH THE LEE
SLOPES INTO DESERTS AFTER 19Z, WITH GUSTS 30-50 KTS. WINDS PERSIST
THROUGH SATURDAY. AREAS OF MODERATE UP/DOWNDRAFTS IN LEE OF
MOUNTAINS.
MARINE
NORTHWSTERLY WINDS PICK UP THIS AFTERNOON AND CONTINUE TO INCREASE
OVERNIGHT. BY EARLY FRIDAY, 15-20 KT WINDS WITH GUSTS TO 25 KTS ARE
EXPECTED TO PERSIST THROUGH SATURDAY MORNING. WINDS REMAIN ELEVATED
SATURDAY AFTERNOON BEFORE WEAKENING LATE SATURDAY INTO SUNDAY.
SEAS INCREASE EARLY FRIDAY TO 6-11 FEET IN THE OUTER COASTAL WATERS
WITH SHORT PERIODS OF 7-9 SECONDS, DIMINISHING THROUGHOUT THE DAY
SATURDAY. SMALL CRAFT ADVISORY IS IN EFFECT AND CONTAINS MORE
DETAILS. CHOPPY SEAS AND HAZARDOUS BOATING CONDITIONS ARE LIKELY.
OTHERWISE, NO HAZARDOUS MARINE CONDITIONS ARE EXPECTED BEFORE AND
AFTER THAT PERIOD.
BEACHES
ELEVATED SURF 4-6 FEET, WITH LOCAL SETS TO 8 FEET ON WEST-FACING
BEACHES, AND HIGH RIP CURRENT RISK EXPECTED FRIDAY AND SATURDAY.
SKYWARN
SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE
ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.
SGX WATCHES/WARNINGS/ADVISORIES
CA...NONE.
PZ...SMALL CRAFT ADVISORY FROM 5 AM FRIDAY TO 5 AM PDT SATURDAY FOR
WATERS FROM SAN MATEO POINT TO THE MEXICAN BORDER EXTENDING
10 TO 60 NM OUT INCLUDING SAN CLEMENTE ISLAND.
PUBLIC...17
AVIATION/MARINE/BEACHES...WESTERINK/ZUBER
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page