Damaging Wind in California, July 30, 2003

INTERIOR CENTRAL CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HANFORD CA
240 PM PDT WED JUL 30 2003

RADAR CONTINUES TO SHOW MORE SHOWERS AND THUNDERSTORMS DEVELOPING
OVER THE SOUTHERN PARTS OF THE DISTRICT THIS AFTERNOON. RUC
ANALYSIS IS SHOWING THIS AREA AS HAVING THE STRONGEST SURFACE
MOISTURE FLUX CONVERGENCE THIS AFTERNOON. THEREFORE...WILL EXPECT
CONVECTION TO CONTINUE OVER THE SOUTHERN HALF WITH MINIMAL
DEVELOPMENT OVER THE NORTH. THIS HAS BEEN AND WILL CONTINUE TO
BE A LOW PRECIP EVENT. THIS MORNINGS UPPER AIR OBSERVATIONS
FROM DESERT ROCK SHOWS THE INVERTED-V PROFILE. MODELS SOUNDING OVER
THE KERN DESERTS AND SOUTHERN SAN JOAQUIN VALLEY ALSO SHOW A SIMILAR
PROFILE. YET...WIND HAS NOT BE A BIG FACTOR TODAY. HOWEVER...WILL
CONTINUE WITH PREVIOUS THINKING OF THIS BEING A LOW QPF EVENT WITH
ISOLATED GUSTY WINDS POSSIBLE. WATER VAPOR IMAGERY WITH RUC80
ANALYSIS CONTINUES TO SHOW THE REX BLOCK AXIS OVER CALIFORNIA WITH A
STRONG EASTERLY FLOW PUSHING INTO THE DISTRICT. WITH LITTLE CHANGE
EXPECTED IN THE NEXT 24 HOUR...WILL EXPECT FURTHER DEVELOPMENT THIS
EVENING.

THIS MORNING SHORT TERM MODEL PRODUCTION SHOWS THE BEST CONVECTIVE
POTENTIAL OVER THE SIERRA NEVADA...KERN MOUNTAINS AND SOUTHERN SAN
JOAQUIN VALLEY. WHILE SOME INSTABILITY WAS NOTED OVER THE CENTRAL
SAN JOAQUIN THIS MORNING...MODELS ADVECT MORE STABLE AIR INTO THE
CENTRAL SJV FROM THE NORTH. THIS ADVECTION WILL MINIMIZE ANY
FURTHER DEVELOPMENT THIS EVENING...YET WILL NOT RULE OUT ANY
THUNDERSTORMS FROM DRIFTING TOWARDS MERCED COUNTY. MODELS SEEM A
BIT TO AGGRESSIVE AT TERMINATING THE CONVECTIVE DEVELOPMENT INTO
THURSDAY. WITH LITTLE MOVEMENT IN THE BLOCKING PATTERN...WILL
EXPECT ADDITIONAL MONSOONAL MOISTURE TO ADVECT ACROSS THE DISTRICT
TONIGHT AND THURSDAY. THEREFORE...WILL BACK OFF THE MODELS ATTEMPT
TO INTRODUCE A DRY WEDGE OF AIR IN FROM THE SOUTH ON THURSDAY. WILL
EXPECT A REPEAT OF TODAY EVENTS ON THURSDAY AND SLOW THE DRYING
MORE TOWARDS FRIDAY. MODELS ARE STARTING TO THE UPPER LOW LIFTING
NORTH ON FRIDAY AND ALLOWING THE FLOW TO BECOME MORE SOUTHERLY. AT
WHICH TIME...WILL EXPECT THE PRECIP TO RETREAT BACK INTO THE
MOUNTAINS. CURRENT TREND IS TO SLOWING DECREASE THE COVERAGE OF
SHOWERS AND THUNDERSTORMS THROUGH OUT THE SHORT TERM PERIOD INTO
THE EXTENDED. THE FLOW DOESN/T TRULY BECOME SOUTHWESTERLY UNTIL WELL
INTO THE EXTENDED...AT WHICH TIME MUCH OF THE DISTRICT BEGINS TO
DRY OUT.

FOR THE EXTENDED FORECAST PERIOD SUNDAY THROUGH WEDNESDAY...MEDIUM
RANGE MODELS ARE IN REASONABLE AGREEMENT THROUGH MONDAY. DRIER
SOUTHWESTERLY FLOW ALOFT SHOULD PREVAIL OVER THE AREA AS THE
MID/UPPER HIGH CONTINUES ITS RETREAT SOUTHEASTWARD FROM THE GREAT
BASIN AREA AND A SHORTWAVE TROUGH TRACKS NORTHEAST ACROSS CENTRAL
CALIFORNIA. FOR SUNDAY...ONLY ISOLATED CONVECTION OVER THE SIERRA
CREST IS EXPECTED. BY MONDAY A DEEPENING PACIFIC TROUGH SHOULD
APPROACH THE NORTHWEST US COAST. THE GFS IS MOST AGGRESSIVE
DEEPENING THE TROUGH AND BRINGING IT ASHORE BY TUESDAY...WHILE THE
ECMWF LAGS FAR BEHIND. FORECAST IS GENERALLY BETWEEN THE TWO
SOLUTIONS. STRONGER ONSHORE FLOW THROUGH THE PERIOD IS A GOOD
BET...WITH TEMPERATURES REMAINING SEVERAL DEGREES COOLER THAN RECENT
READINGS AND DRY CONDITIONS PREVAILING OVER THE ENTIRE DISTRICT.

.HNX...NONE.

MOLINA/BAGNALL

CAZ089>099-311230-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
530 AM PDT WED JUL 30 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE CENTRAL CALIFORNIA
INTERIOR.

.DAY ONE...TODAY

THERE IS A CHANCE OF THUNDERSTORMS OVER PORTIONS OF THE
SOUTHERN SIERRA NEVADA AND THE KERN COUNTY DESERTS TODAY. THERE ALSO
EXISTS A SLIGHT CHANCE OF THUNDERSTORMS FOR THE REMAINDER OF THE
CENTRAL CALIFORNIA INTERIOR. ANY OF THESE THUNDERSTORMS MAY CONTAIN
GUSTY WINDS...DANGEROUS LIGHTNING...AND BRIEF HEAVY RAINFALL.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THERE IS A CHANCE OF THUNDERSTORMS OVER PORTIONS OF THE SOUTHERN
SIERRA NEVADA...THE KERN COUNTY DESERTS...AND THE CENTRAL AND
SOUTHERN SAN JOAQUIN VALLEY ON THURSDAY. NO OTHER HAZARDOUS WEATHER
IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS TO THEIR LOCAL NATIONAL WEATHER SERVICE OFFICE.