Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
000
FXUS66 KHNX 280455
AFDHNX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
855 PM PST TUE JAN 27 2015

.SYNOPSIS...
ANOTHER LOW PRESSURE SYSTEM WILL BRING A RENEWED CHANCE OF SHOWERS
TO MAINLY THE MOUNTAINS AND DESERT WEDNESDAY NIGHT INTO FRIDAY.
OTHERWISE EXPECT MAINLY DRY CONDITIONS WITH NEAR TO SLIGHTLY ABOVE
AVERAGE TEMPERATURES THROUGH THE NEXT SEVERAL DAYS.

&&

.DISCUSSION...
RADAR AND SURFACE OBSERVATIONS INDICATE THAT PRECIPITATION HAS
ENDED OVER THE CENTRAL CALIFORNIA INTERIOR AND SKIES ARE CLEARING
FOR THE MOST PART. ONE EXCEPTION IS THE SOUTH END OF THE SAN JOAQUIN
VALLEY...WHERE CLOUDS ARE POOLED AND PUSHING AGAINST THE VALLEY-
FACING SLOPES. THIS HAS PRODUCED DENSE FOG IN THE TEHACHAPI AREA...
WHERE TEHACHAPI MUNICIPAL AIRPORT /KTSP/ HAS BEEN REPORTING
VISIBILITIES OF LESS THAN A QUARTER MILE.

HAVE UPDATED THE FORECAST TO REMOVE POPS...WEATHER...QPF AND SNOW
FROM THE SOUTHERN SIERRA NEVADA TONIGHT...AND TO ADD PATCHY DENSE
FOG ALONG THE VALLEY-FACING SLOPES OF THE KERN COUNTY MOUNTAINS AND
INTO THE PASSES THROUGH 18Z /1000 PST/ WEDNESDAY.

ANOTHER AREA OF CONCERN THIS EVENING IS THE KERN COUNTY DESERT AND
INDIAN WELLS VALLEY...WHERE UP TO A HALF INCH OF RAIN FELL. WITH
CLEAR SKIES AND LIGHT WIND...PATCHY FOG IS POSSIBLE. PER DISCUSSION
WITH WFO/S OXNARD...LAS VEGAS AND SAN DIEGO...HAVE ADDED PATCHY
FOG TO THE INDIAN WELLS VALLEY AND THE SOUTHEASTERN KERN COUNTY
DESERT THROUGH 18Z WEDNESDAY.

FOR THE CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY...CLEAR SKIES AND
LIGHT WIND WILL BE FAVORABLE FOR PATCHY FOG DEVELOPMENT AFTER
MIDNIGHT. RAINFALL AMOUNTS TUESDAY NIGHT INTO TODAY WERE MOSTLY LIGHT
WITH ONLY A FEW STATIONS REACHING AROUND A QUARTER INCH. SOME OF
THIS MOISTURE WILL RECHARGE THE BOUNDARY LAYER WEDNESDAY...SO COULD
SEE SOME PATCHY FOG WEDNESDAY EVENING. HOWEVER...ANOTHER TROUGH IS
FORECAST TO MOVE INTO CALIFORNIA THURSDAY AND SHOULD KEEP THE LOWER
ATMOSPHERE MIXED ENOUGH TO PREVENT FURTHER FOG DEVELOPMENT UNTIL THE
WEEKEND...WHEN THE NEXT UPPER-LEVEL RIDGE BUILDS INTO CENTRAL
CALIFORNIA.

&&

.PREV DISCUSSION... /ISSUED 339 PM PST TUE JAN 27 2015/

DISCUSSION...SHOWER ACTIVITY QUICKLY DIMINISHING AS AN UPPER LOW
MOVES NE OF THE SIERRA. THE SOUTH VALLEY HAS CLEARED OUT WITH
SHOWERS LIMITED MAINLY TO THE MOUNTAINS. EXPECT ALL SHOWER
ACTIVITY TO END DURING THE EARLY EVENING. WEATHER RADAR
PRECIPITATION ESTIMATES SHOWS WIDESPREAD LIGHT PRECIPITATION
FALLING OVER MUCH OF DISTRICT WITH THE HEAVIER AMOUNTS OF 0.6-1.0
INCH OVER THE TEHACHAPI MOUNTAINS AND INDIAN WELLS VALLEY. CONCERN
FOR THE POTENTIAL FOR FOG IN THE SJV TONIGHT. DEW POINTS RUNNING
RELATIVELY HIGH WITH THE RECENT RAINFALL. WINDS SHOULD REMAIN
LIGHT AS SHORT WAVE RIDGING BUILDS BEHIND THE EXITING TROUGH. A
MITIGATING FACTOR WILL BE AMOUNT OF REMNANT CLOUD COVER. HOWEVER
MODELS PROG DECREASING MID LEVEL MOISTURE BEHIND THE TROUGH.

HIGH LEVEL CLOUD COVER WILL BE ON THE INCREASE WEDNESDAY AS AN
UPPER TROUGH OFF BAJA MOVES TOWARDS THE SOCAL COAST. SATELLITE PW
ESTIMATES INDICATE LOTS OF TROPICAL MOISTURE AHEAD OF THIS SYSTEM.
HOWEVER MODELS PROG THE DEEP MOISTURE TO PUSH THROUGH THE SONORAN
DESERT AND REMAIN EAST OF THE COLORADO RIVER. MODELS SPLIT THE
TROUGH AS IT MOVES ONSHORE WITH THE STRONGER DYNAMICS MOVING
TROUGH N BAJA. THUS MODEL FORECAST LIGHT AMOUNTS OF PRECIPITATION
MAINLY OVER THE MOUNTAINS AND DESERT. PRECIPITATION COULD BEGIN
WEDNESDAY NIGHT AND DIMINISH THURSDAY NIGHT. THE ENSEMBLE MEAN
TRENDS REMAIN INCONSISTENT WITH THE TRACK OF THIS LOW...GIVING
FORECASTERS VERY LITTLE CONFIDENCE IN MEASURABLE RAIN...ESPECIALLY
FOR THE DESERT.

ONCE THE UPPER LOW EXITS EAST...HIGH PRESSURE WILL BUILD OVER THE
REGION SATURDAY INTO SUNDAY...WITH THE OPERATIONAL AND ENSEMBLE
MEANS ALL IN AGREEMENT. THE BEGINNING OF NEXT WEEK LOOKS A BIT
LESS CERTAIN...AS NCEP/S GLOBAL ENSEMBLE SHOWING VERY LOW
PREDICTABILITY FOR THE UPPER LEVEL PATTERN FOR THE BEGINNING OF
NEXT WEEK. REGARDLESS...BOTH THE GFS AND ECMWF ARE INDICATING DRY
WEATHER.

PATCHY FOG WILL ONCE AGAIN BE POSSIBLE THROUGH MANY VALLEY
LOCATIONS STARTING AS THURSDAY. PATCHY FOG WILL BE POSSIBLE EACH
NIGHT AND EARLY MORNING FROM THURSDAY INTO EARLY NEXT WEEK.

&&

.AVIATION...
MVFR CEILINGS CAN BE EXPECTED ALONG THE WEST SLOPES OF THE SIERRA
AND THE NORTH FACING SLOPES OF THE TEHACHAPI MOUNTAINS UNTIL 18Z
WEDNESDAY WITH IMPROVEMENT TO VFR THEREAFTER. AREAS OF IFR
CEILINGS AND VISIBILITIES ARE POSSIBLE IN THE SAN JOAQUIN VALLEY
BETWEEN 06Z AND 18Z WEDNESDAY WITH LOCAL LIFR/VLIFR IN FOG. VFR
CONDITIONS WILL PREVAIL ELSEWHERE THROUGHOUT THE CENTRAL
CALIFORNIA DURING THE NEXT 24 HOURS.

&&

.AIR QUALITY ISSUES...
ON WEDNESDAY JANUARY 28 2015... FIREPLACE/WOOD STOVE BURNING
STATUS IS: NO BURNING UNLESS REGISTERED IN FRESNO... KERN...
KINGS... MADERA... MERCED AND TULARE COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG

&&

.CERTAINTY...

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

THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
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 01-27       70:1934     39:1963     52:2012     25:1949
KFAT 01-28       78:1986     41:1963     50:2003     23:1975
KFAT 01-29       73:1960     43:2002     55:1911     24:1902

KBFL 01-27       75:1928     37:1963     51:2012     24:1904
KBFL 01-28       77:1988     47:1957     52:1981     27:1957
KBFL 01-29       74:1986     42:2002     54:1986     27:1903
&&

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

&&

$$

PUBLIC...SANGER
AVN/FW...MOLINA/DURFEE
PREV DISCUSSION...MV
SYNOPSIS...BSO

WEATHER.GOV/HANFORD



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.