000
FXUS66 KSGX 152020
AFDSGX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
120 PM PDT SAT JUN 15 2013

.SYNOPSIS...
SEASONAL JUNE WEATHER WILL PREVAIL THROUGH NEXT WEEKEND. THE MARINE
LAYER WILL CONTINUE AREAS OF NIGHT AND MORNING LOW CLOUDS AND FOG
EXTENDING INTO THE VALLEYS EACH NIGHT AND MORNING...WHILE SKIES
REMAIN CLEAR FAR INLAND. A TROUGH OF LOW PRESSURE MOVING INLAND TO
THE NORTH MIDWEEK WILL TEMPORARILY DEEPEN THE MARINE LAYER AND BRING
ADDITIONAL MARINE CLOUDS AND COOLING. WARMER AGAIN LATE NEXT WEEK AS
THE ONSHORE FLOW WEAKENS. THE PERSISTENT ONSHORE FLOW WILL ALSO
BRING LOCALLY GUSTY WESTERLY WINDS OVER THE MOUNTAINS AND INTO THE
DESERTS LATE EACH DAY THROUGH LATE EVENING.

&&

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

WITH THE SUMMER SOLSTICE JUST AROUND THE CORNER...DAYLIGHT OVER THE
NORTHERN HEMISPHERE HAS JUST ABOUT PEAKED. SUNRISES ARE ALREADY
STARTING TO SLIP LATER HERE IN SAN DIEGO...BUT IT WON`T BE UNTIL
EARLY NEXT WEEK THAT WE SEE THE LATEST SUNSET AROUND 8 PM PDT.

THE MARINE STRATUS BEAT A HASTY RETREAT OFFSHORE THIS MORNING BUT
REMAINED EXTENSIVE OFFSHORE AT MIDDAY. AT NOON...SURFACE PRESSURE
GRADIENTS WERE 4-7 MBS ONSHORE TO THE DESERTS WITH MODERATE ONSHORE
TRENDS. WESTERLY WINDS HAD PICKED UP ACROSS THE HIGH DESERT AND
THROUGH THE BANNING PASS AREA AT 15 TO 25 MPH WITH HIGHER GUSTS.

NO SIGNIFICANT CHANGES MADE TO THE PREVIOUS FORECAST OVER THE NEXT 8
DAYS.

A DEEP LOW PRESSURE SYSTEM WAS CENTERED OFF THE PACNW COAST NEAR
140W THIS AFTERNOON. THE BROAD CIRCULATION AROUND THIS LOW COVERED
THE WEST COAST. THE LOW IS EXPECTED TO DRIFT SLOWLY EASTWARD...
REACHING OREGON ON WED. WHEN IT MOVES INLAND...MODEST HEIGHT FALLS
AND ONSHORE FLOW WILL PROVIDE ADDITIONAL DEEPENING OF THE MARINE
LAYER AND INLAND COOLING TUE/WED. UNTIL THEN...SOME WARMING IS
LIKELY INLAND AS THE MARINE LAYER SHRINKS UNDER WEAK RIDGING ALOFT.
WESTERLY WINDS WILL BECOME GUSTY BY LATE AFTERNOON OVER THE
MOUNTAINS AND INTO THE DESERTS...AND CONTINUE LATE EACH EVENING.

THERE IS AGREEMENT IN THE GENERAL PATTERN OVER NORTH AMERICA BETWEEN
THE GLOBAL MODELS/RUNS WELL OUT INTO THE MEDIUM RANGE. THE ECMWF
ENSEMBLE MEAN KEEPS A LONG-WAVE TROUGH POSITION NEAR THE WEST
COAST...WITH A FLAT RIDGE OVER THE FAR SOUTHERN PLAINS AND GULF
COAST REGION. THIS SHOULD CONTINUE DRY...SEASONAL WEATHER OVER SOCAL
THROUGH NEXT WEEKEND WITH MARINE CLOUDS EACH NIGHT/MORNING...AND
VERY WARM DAYS INLAND OVER THE FOOTHILLS/MTNS/DESERTS. TYPICAL SEA
BREEZES WEST OF THE MOUNTAINS...BECOMING GUSTY LATE EACH DAY/EVENING
THROUGH THE PASSES AND INTO THE DESERTS. STRONGEST MTN/DESERT WINDS
ARE EXPECTED TUE...WHEN LOCAL GUSTS AROUND 40 MPH ARE POSSIBLE.

&&

.AVIATION...
151938Z...COAST/VALLEYS...THROUGH 16/0200 UTC...MOSTLY SKC AND
UNRESTRICTED VIS. 16/0200-0600 UTC...STRATUS MOVING BACK INLAND AND
EVENTUALLY REACHING 25-45 SM INLAND AGAIN BY 16/1400 UTC...WITH
BASES 1300-1600 FT MSL AND TOPS AROUND 2600-2900 FT MSL. CLEARING TO
THE COASTAL WATERS DURING THE 16/1500-1800 UTC TIME-FRAME.

MTNS/DESERTS...SKC WITH UNRESTRICTED VSBY THROUGH SUNDAY MORNING.

&&

.MARINE...
INCREASING WINDS NEAR POINT-CONCEPTION LATE MONDAY INTO TUESDAY WILL
BRING A FRESH SHORT-PERIOD NORTHWEST SWELL...PEAKING AT 8-9 FEET IN
THE OUTER WATERS SOUTH OF SAN CLEMENTE ISLAND. THIS WILL RESULT IN
CHOPPY SEA CONDITIONS...ESPECIALLY IN THE OUTER WATERS...FOR TUESDAY
INTO WEDNESDAY.

ALSO...WEST TO NORTHWESTERLY WINDS WILL STRENGTHEN TUESDAY...WITH
GUSTS POSSIBLY REACHING 25 KNOTS DURING THE AFTERNOON AND EVENING
HOURS...MAINLY OVER THE OUTER WATERS.

&&

.FIRE WEATHER...
SEASONAL CONDITIONS WILL PREVAIL ACROSS THE REGION. VERY DRY ABOVE
THE MARINE LAYER WITH RELATIVE HUMIDITY BELOW 15 PERCENT AT HIGHER
ELEVATIONS AND EASTWARD INTO THE DESERTS EACH DAY. GUSTY ONSHORE
BREEZES WILL DEVELOP EACH AFTERNOON/EVENING...STRONGEST NEAR THE
PASSES AND ON THE DESERT SLOPES WHERE WINDS WILL GUST LOCALLY TO 35
MPH OR MORE FOR A FEW HOURS. STRONGEST WINDS ARE EXPECTED LATE TUE/
TUE EVENING WHEN GUSTS THROUGH AND BELOW THE WINDIEST PASSES COULD
TOP 40 MPH FORE A FEW HOURS.

THE MARINE LAYER WILL FLUCTUATE IN DEPTH THIS WEEK. REMAINING NEAR
2500 FEET DEEP TONIGHT...THEN LOWERING MON NIGHT. IT WILL BE DEEPEN
BACK UP TO AROUND 3000 FEET ON TUE NIGHT/WED. RH WILL REMAIN
SEASONALLY HIGH AT LOWER ELEVATIONS WEST OF THE MOUNTAINS WITH
CONTINUED ONSHORE FLOW. SEA BREEZES WILL BE WEAK TO MODERATE INTO
THE WESTERN VALLEYS EACH DAY.

&&

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

&&

$$

PUBLIC/FIRE WEATHER...JAD
AVIATION/MARINE...HARRISON