Wildfire in California, August 18 to 27, 2014

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
203 PM PDT MON AUG 18 2014

.SYNOPSIS...AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL MOVE DOWN
THE CALIFORNIA COAST AND BRING A COOLING TREND THROUGH
TOMORROW...THEN LITTLE CHANGE IN TEMPERATURES WILL OCCUR THE
REMAINDER OF THE WEEK.

&&

.DISCUSSION...A FAST MOVING UPPER VORT MAX PUSHED NORTHEAST ACROSS
CENTRAL CA THIS MORNING PROVIDING OUR AREA WITH SOME MID/HIGH
CLOUDS EARLIER TODAY. THIS DISTURBANCE HAS SINCE MOVED OFF INTO NV
GIVING WAY TO A MOSTLY SUNNY AFTERNOON ACROSS OUR AREA. A SHALLOW
INTRUSION OF MARINE COOLED AIR PUSHED INTO THE CENTRAL SAN
JOAQUIN VALLEY OVER NIGHT...BUT P-GRADS RELAXED EARLIER THAN
ANTICIPATED AND TEMPERATURES HAVE ONLY COOLED 2-3 DEG F FROM YDAY
ACROSS THE CENTRAL SAN JOAQUIN VALLEY. ACROSS THE REMAINDER OF OUR
CWFA...TEMPERATURES HAVE BEEN RUNNING CLOSE TO YDAY.

MEANWHILE...WV IMAGERY AND GOES HIGH DENSITY WINDS ARE INDICATING
AN UPPER LOW CENTERED OVER NORTHWESTERN CA NEAR 41N/124W WHICH
HAS BEEN DROPPING SOUTHWARD FASTER THAN EARLIER ANTICIPATED. THE
LOW IS PROGGED TO DROP CONTINUE DROPPING SOUTHWARD TONIGHT AND
TUESDAY TO JUST OFF THE CENTRAL CA COAST BY TUESDAY AFTERNOON. IN
RESPONSE TO LOWERING HEIGHTS AND THICKNESSES...MAXIMUM
TEMPERATURES ACROSS OUR AREA TO BE 5-10 DEG F COOLER ON TUESDAY
THAN TODAY AND NEAR TO SLIGHTLY BELOW SEASONAL NORMALS.

THE ENSEMBLE MEANS INDICATE THAT THE LOW WILL DROP INTO SOCAL ON
TUESDAY NIGHT THEN PUSH INLAND INTO THE DESERT SOUTHWEST BY
WEDNESDAY NIGHT. THE 12Z GFS HAS A GOOD HANDLE ON THE FASTER
TIMING AND IS IN FAIRLY GOOD AGREEMENT WITH THE ENSEMBLE MEANS
WHILE THE 12Z ECMWF LAGS THEM A BIT AND HANGS THE LOW OVER SOCAL
FOR AN EXTRA DAY BEFORE EJECTING IT INTO THE DESERT SOUTHWEST BY
THURSDAY NIGHT. THE WRF IS SLOWER WITH THE SOUTHWARD PROGNOSIS OF
THE LOW AND HAS BEEN DISREGARDED AS THE MOVEMENT OF THIS SYSTEM IS
TRENDING FASTER. AS THE LOW DROPS WEST OF OUR AREA ON TUESDAY IT
WILL DESTABILIZE THE ATMOSPHERE ENOUGH FOR SOME AFTERNOON CUMULUS
BUILD-UPS OVER THE SOUTHERN SIERRA NEVADA...BUT THUNDERSTORMS ARE
UNLIKELY SINCE THE LOW IS MOISTURE DEFICIENT AS NOTED FROM WV
IMAGERY. WILL THEREFORE KEEP A DRY FORECAST FOR NOW. A COOL AND DRY
NORTHERLY FLOW WILL PREVAIL OVER CENTRAL CA BEHIND THE LOW ON
WEDNESDAY. AS A RESULT...TEMPERATURES WILL REMAIN NEAR TO
SLIGHTLY BELOW NORMAL AND ANY CONVECTION WILL BE CONFINED TO A FEW
BUILD-UPS NEAR THE SIERRA CREST AS RH PROGS INDICATE MOISTURE
WILL BE LACKING.

FOLLOWING THE DEPARTURE OF THE UPPER LOW LATER IN THE WEEK AS A
TROUGH DIGS INTO THE GREAT BASIN...CENTRAL CA WILL REMAIN UNDER A
DRY NORTHWEST FLOW FRIDAY THROUGH THE WEEKEND AND INTO THE EARLY
PORTION OF NEXT WEEK. THE ECMWF DOES INDICATE AN UPPER SHORTWAVE
DROPPING OFF THE NORCAL COAST ON SUNDAY FORMING A BAGGY TROUGH BY
EARLY NEXT WEEK AND TURN THE UPPER FLOW TO SOUTHWEST TO WEST AND
SUBSEQUENTLY HEIGHT RISES AND RISING DIURNAL TEMPERATURES WHILE
THE GFS AMPLIFIES AN UPPER RIDGE OFF THE COAST AND KEEPS A COOLER
NORTHWEST FLOW OVER CENTRAL CA. FOR NOW WILL COMPROMISE BETWEEN
THE TWO SOLUTIONS AND GO WITH A SLIGHT WARMING TREND EARLY NEXT
WEEK. REGARDLESS OF WHICH SOLUTION PANS OUT...CONFIDENCE HAS
IMPROVED FOR ANY TROPICAL MOISTURE FROM TROPICAL DEPRESSION 12-E
CURRENTLY SITUATED NEAR 17N/118W TO REMAIN TO THE SOUTH OF OUR
CWFA AND NOT IMPACT OUR AREA. WE ARE THEREFORE NOT EXPECTING ANY
PRECIPITATION IN OUR AREA DURING THE MEDIUM RANGE PERIOD.

&&

.AVIATION...VFR CONDITIONS WILL PREVAIL OVER THE NEXT 24 HOURS.

&&

.AIR QUALITY ISSUES...NONE.

&&

.CERTAINTY...

THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS MEDIUM.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.

CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.

&&

.CLIMATE...
             RECORDS
SITE DATE    HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR

KFAT 08-18      112:1892     77:1975     75:2012     52:1916
KFAT 08-19      108:1892     67:1976     74:2012     54:1916
KFAT 08-20      108:1919     76:1959     75:1986     54:1974

KBFL 08-18      110:1942     82:1916     80:2012     50:1905
KBFL 08-19      109:1950     78:1959     79:1961     52:1913
KBFL 08-20      112:1950     77:1959     79:1950     52:1912
&&

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

&&

PUBLIC...DS
AVN/FW...JEB
SYNOPSIS...PJ

WEATHER.GOV/HANFORD