Area Forecast Discussion
Issued by NWS San Diego, CA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS66 KSGX 300333
AFDSGX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
832 PM PDT SUN MAR 29 2015

.SYNOPSIS...HIGH PRESSURE ALOFT OVER THE WEST WILL WEAKEN THROUGH
THURSDAY RESULTING IN A SLOW COOLING TREND. AREAS OF NIGHT AND
MORNING LOW CLOUDS AND FOG WILL CONTINUE ALONG THE COAST...AND MAY
SPREAD FARTHER INLAND BY THURSDAY AS GUSTY ONSHORE FLOW DEVELOPS
OVER THE MOUNTAINS AND DESERTS. FAIR AND WARMER AGAIN LATE IN THE
WEEK WITH WEAK OFFSHORE FLOW...THEN MUCH COOLER BEGINNING LATE IN
THE WEEKEND AS A COLD TROUGH DROPS SOUTH ALONG THE WEST COAST...
ACCOMPANIED BY A DEEPER MARINE LAYER AND GUSTY WESTERLY WINDS ACROSS
THE MOUNTAINS AND DESERTS.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

AS WAS THE CASE YESTERDAY EVENING...HIGH CLOUDS HAVE THICKENED
ACROSS THE REGION OBSCURING THE LOWER CLOUDS. HOWEVER...WHERE
VISIBLE...LOWER CLOUDS WERE EVIDENT OVER THE CA BIGHT AND FARTHER
OFFSHORE. THE 00Z MIRAMAR SOUNDING HAD A WEAK INVERSION BASED NEAR
1500 FT. THE SURFACE PRESSURE GRADIENTS WERE ALMOST NEUTRAL FROM
NV...BUT HAD INCREASED ONSHORE TO 4-6 MBS TO THE LOWER DESERTS.
WINDS WERE GENERALLY LIGHT.

BASED ON THE HEIGHT OF THE MOIST LAYER...AND DECREASED DEWPOINT
DEPRESSIONS...IT IS LIKELY SOME PATCHY RADIATIONAL FOG WILL DEVELOP
OVERNIGHT AS THE HIGHER CLOUDS BREAK...BUT DIFFICULT TO PINPOINT
EXACT LOCATIONS.

BROAD RIDGING ALOFT WILL CONTINUE OVER THE WEST THROUGH MON...THEN
FLATTEN AS A SERIES OF SHORT WAVES SLIDE EAST OFF THE PACIFIC. THIS
WILL SUPPRESS HEIGHTS/THICKNESS OVER CA THROUGH THU...AND CONTINUE
ONSHORE FLOW AND A MARINE LAYER WEST OF THE MTS. WINDS WILL BECOME
GUSTY OVER THE MTS/DESERTS AS THE TROUGHS PASS BY TO THE NORTH...AND
DAYTIME TEMPERATURES WILL GRADUALLY LOWER INLAND.

FOR FRIDAY...RIDGING WILL FOLLOW...SWINGING SFC WINDS BACK OFFSHORE
ACROSS SOCAL AS HIGH PRESSURE BUILDS INTO THE GREAT BASIN. DEPENDING
ON THE STRENGTH OF THE OFFSHORE PUSH...DAYTIME TEMPERATURES COULD
CLIMB BACK UP TO NEAR 80 ALONG THE COAST BEFORE WINDS TURN BACK
ONSHORE SAT AFTERNOON.

MORE SIGNIFICANT CHANGES MAY BE IN THE OFFING LATE NEXT WEEKEND
THROUGH THE FOLLOWING WEEK AS A COLDER TROUGH SETTLES OVER THE WEST
COAST. SEVERAL OF THE EC/GFS DETERMINISTIC RUNS HAVE SUGGESTED A
FLIP-FLOP OF THE PERSISTENT WEST COAST RIDGE/EAST COAST TROUGH
PATTERN FOR THE WEEK OF APRIL 5. THE LATEST AVAILABLE RUNS ALSO HAVE
PRECIP OVER SOCAL CENTERED AROUND APRIL 8. SO...PERHAPS WE WILL HAVE
A CHANCE OF MORE PRECIPITATION BEFORE THE SEASON SHUTS DOWN
COMPLETELY.

&&

.AVIATION... 300300Z...COASTAL AREAS...PATCHES OF LOW CLOUDS ARE
BEGINNING TO RETURN TO THE IMMEDIATE COAST AT THIS TIME. THEY WILL
LIKELY IMPACT THE COASTAL TAF SITES AFT 05Z WITH BKN-OVC CIGS
BETWEEN 900 AND 1200 FT MSL AND TOPS TO 1500 FT. EXPECT REDUCED VIS
IN AREAS WHERE CLOUDS AND TERRAIN INTERSECT...MAINLY ALONG THE
COASTAL MESAS. LOW CLOUDS AND FOG WILL LIKELY CLEAR BY 16Z MON.

VALLEYS/MOUNTAINS/DESERTS...SCT-FEW CLOUDS AOA 15000 FEET WITH
UNRESTRICTED VIS THROUGH MONDAY.

&&

.MARINE...

800 PM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH TUESDAY.

&&

.BEACHES...

800 PM...SLIGHTLY ELEVATED SURF WILL CONTINUE THROUGH THE FIRST HALF
OF THIS WEEK THOUGH THE RIP CURRENT THREAT WILL GRADUALLY DIMINISH
AS THE SWELL PERIOD DECREASES.

&&

.SKYWARN... SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER
SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE

PZ...NONE.
&&

$$

PUBLIC...JAD
AVIATION/MARINE/BEACHES...PG



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.