FXUS66 KHNX 061621
AFDHNX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
921 AM PDT SAT SEP 6 2008

.UPDATE...
OFFSHORE PATTERN CONTINUES TO PROVIDE CLEAR AND DRY CONDITIONS THIS
MORNING. SMOKE FROM A FIRE IN SIERRA FOREST HAS BEEN INFILTRATING
INTO THE VALLEY OVERNIGHT AND WILL LIKELY RESULT IN HAZY
CONDITIONS TODAY. PROFILERS SHOW 1-2C DEGREES WARMING AT LOWER
LEVELS WITH SOUNDINGS INDICATING 1-3C DEGREES WARMER FROM 3KFT-
10KFT. 12Z VANDENBERG SOUNDING INDICATES STRONGER EASTERLY FLOW
WITH LIGHTER FLOW TOWARDS OAK. THIS SHOULD PROVIDE DRIER CONDITIONS
TOWARDS THE TEHACHAPIS AND WARMER TEMPERATURES REGION WIDE. DO NOT
PLAN ON A MORNING UPDATE.

&&

.DISCUSSION...UNLIKE THE EAST COAST, THE WEATHER OVER CENTRAL
CALIFORNIA IS ABOUT AS TRANQUIL AS IT GETS. VERY HIGH AMPLITUDE
EAST PACIFIC RIDGE CONTINUES TO DOMINATE THE PATTERN AND THE HOT
WEATHER WILL CONTINUE THROUGH THE WEEKEND. WATER VAPOR IMAGERY
SHOWS A LITTLE RESIDUAL MID LEVEL MOISTURE OVER THE AREA HOWEVER
ANY CONVECTION OVER THE SIERRA WILL BE SQUASHED BY THE SUBSIDENCE
UNDER THE RIDGE. AS FOR TEMPERATURES, TODAY WILL BE AS HOT AS
FRIDAY AND IN MANY LOCATIONS ANOTHER 1-2 DEGREES OF WARMING WILL
OCCUR. ON SUNDAY CONDITIONS WILL SHOW CHANGE AS THE HOT AIRMASS
WILL REMAIN IN PLACE. FORECAST MODELS DO BEGIN TO SHOW SOME CHANGE
IN THE PATTERN AS A SHORTWAVE TROUGH IS PROGGED TO DROP SOUTHWARD
INTO NORTHERN CALIFORNIA AND THEN "WASH OUT" OVER CENTRAL
CALIFORNIA SUNDAY NIGHT AND MONDAY. THE MAIN AFFECT OF THIS
FEATURE WILL BE TO LOWER HEIGHTS AND ALLOW FOR SOME COOLING. THE
EXTENT OF THE COOLING IS QUESTIONABLE HOWEVER AS ALTHOUGH THE
MODELS KEEP A WEAK 500 MB LOW OVER THE AREA MONDAY AND TUESDAY THE
MEAN EAST PACIFIC RIDGE WILL LINGER OFF THE WEST. ALL IN ALL
CONTINUED QUIET WEATHER TO CONTINUE THROUGH WEDNESDAY. BY THURSDAY
AND FRIDAY THE ECMWF MODEL DEVELOPS A REX BLOCK PATTERN WITH THE
ASSOCIATED HIGH OVER NORTHERN CALIFORNIA AND THE LOW LOCATED ABOUT
500 MILES WEST OF POINT CONCEPTION. THIS PATTERN WOULD BE
FAVORABLE FOR A SOUTHERLY FLOW AND POSSIBLE SUBTROPICAL MOISTURE
ENTRAINMENT INTO THE REGION...IF ANY IS AVAILABLE. FOR NOW WILL
ADD SOME ADDITIONALLY CLOUDS TO THE SIERRA AND KERN MOUNTAINS HOWEVER
WILL KEEP THE POPS OUT OF THE FORECAST FOR NOW. THIS COULD CHANGE
IF FURTHER MODEL SOLUTIONS BACK UP A TROPICAL SURGE SITUATION.



&&

.AVIATION...VFR CONDITIONS WILL PREVAIL ACROSS THE CENTRAL CALIFORNIA
INTERIOR THROUGH 18Z SUNDAY.


&&

.AIR QUALITY ISSUES...
ON SATURDAY SEPTEMBER 6 2008... UNHEALTHY FOR SENSITIVE GROUPS IN
FRESNO... KERN... KINGS... MADERA... MERCED AND TULARE COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG

&&

.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

PUBLIC...MV
AVN/FW...JEB

WEATHER.GOV/HANFORD



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