Southwestern California Discussion
000
FXUS66 KSGX 060331
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
930 PM PDT SUN SEP 5 2010
.SYNOPSIS...UPPER LEVEL LOW PRESSURE MOVING PAST TO THE NORTH WILL
BRING A COOLING TREND AND A DEEPER MARINE LAYER THROUGH MID WEEK.
LOW CLOUDS AND FOG WILL BECOME MORE EXTENSIVE DURING THE NIGHTS AND
MORNINGS WEST OF THE MOUNTAINS. LOCALLY WINDY AT TIMES IN THE
MOUNTAINS AND DESERTS. A LITTLE WARMER TOWARD THE END OF THE WEEK
WITH WEAKER LOW PRESSURE ALOFT.
&&
.DISCUSSION...FOR SOUTHWEST CALIFORNIA INCLUDING SAN DIEGO...
ORANGE...SOUTHWEST SAN BERNARDINO AND WEST RIVERSIDE COUNTIES.
.SHORT TERM (TONIGHT-WEDNESDAY)...SKIES WERE CLEAR THIS EVENING
EXCEPT FOR AREAS OF STRATUS NEAR THE COAST MOVING ONSHORE. THE 00Z
NKX SOUNDING HAD AN INVERSION BASED NEAR 1600 FT...ABOUT 600 FT
HIGHER THAN 24 HOURS PREVIOUS. INCREASING ONSHORE GRADIENTS WITH
ABOUT 8 MB SAN-IPL.
AN UPPER TROUGH WILL DEEPEN OVER THE WESTERN STATES THROUGH
WEDNESDAY. THIS WILL BRING A COOLING TREND AND A DEEPER MARINE
LAYER. MAX TEMPS WILL BE A LITTLE BELOW SEASONAL AVERAGE W OF THE
MOUNTAINS MONDAY AND WELL BELOW BY WEDNESDAY. HIGH TEMPERATURES WILL
BE ABOUT 8 TO 16 DEGREES BELOW AVERAGE IN MOST AREAS WEDNESDAY.
THERE COULD BE SOME NEAR RECORD LOW MAXIMUM TEMPERATURES WEDNESDAY.
THE MARINE LAYER WILL DEEPEN WITH LOW CLOUDS AND FOG BECOMING MORE
EXTENSIVE W OF THE MOUNTAINS EACH NIGHT. STRATUS WILL GET INTO MOST
INLAND VALLEYS AREAS TUESDAY NIGHT. ONLY PARTIAL AFTERNOON CLEARING
IN THE COASTAL AREAS TUESDAY AND WEDNESDAY. THERE ARE ALSO SOME
INDICATIONS OF A LITTLE MID LEVEL MOISTURE TUESDAY THAT COULD CAUSE
A FEW AFTERNOON CLOUDS OVER THE MOUNTAINS. STRONGER ONSHORE FLOW
AND WINDS ALOFT WILL CAUSE LOCAL GUSTY WINDS IN THE MOUNTAINS AND
DESERTS...MAINLY DURING THE AFTERNOONS AND EVENINGS TUESDAY AND
WEDNESDAY.
&&
.LONG TERM (THURSDAY-SUNDAY)...CONTINUED COOL THURSDAY. MARINE LAYER
CLOUDS WILL GET INTO THE LOWER COASTAL MOUNTAIN SLOPES THURSDAY
MORNING WITH PARTIAL AFTERNOON CLEARING. GRADUALLY WARMER WITH A
SHALLOWER MARINE LAYER FRIDAY THROUGH THE WEEKEND AS LOCAL HEIGHTS
RECOVER UNDER WEAKER CYCLONIC FLOW ALOFT. EVEN WITH THE
WARMING...MAX TEMPS WILL STILL BE LOWER THAN SEASONAL AVERAGES.
&&
.AVIATION...
060315Z...MARINE STRATUS LAYER BETWEEN 1K AND 1.5K FT OVER COASTAL
AREAS EARLY THIS EVENING IS EXPECTED TO DEEPEN WITH BASES NEAR 1.5K
FT AND TOPS AROUND FL020 BY MORNING AND PENETRATE 15 TO 20 MILES
INLAND WITH AREAS OF 3-5SM VIS IN BR/HZ...AND LOCAL LIFR CIGS/VIS
FAR INLAND AND OVER HIGHER COASTAL TERRAIN THROUGH 15Z MON. THERE IS
A POTENTIAL FOR IFR CIGS/VIS TO REACH KONT BY MORNING. WILL DROP VIS
THERE BY SUN-UP BUT NOT CONFIDENT ENOUGH TO BRING IN CIGS ATTM.
WIDESPREAD STRATUS/VIS RESTRICTIONS AROUND SUN-UP WEST OF THE MTNS
SHOULD BURN BACK TO THE COAST BETWEEN 16Z AND 19Z MON. ELSEWHERE VFR
CONDITIONS SHOULD PREVAIL UNDER A CLEAR SKY WITH VIS UNRESTRICTED.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...ATKIN
AVIATION...JAD
NWS SGX Office Area Forecast Discussion
