Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA

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FXUS66 KHNX 011100
AFDHNX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
300 AM PST SUN MAR 1 2015

.SYNOPSIS...
A PAIR OF STORM SYSTEMS TRACKING SOUTH INTO CENTRAL CALIFORNIA WILL
BRING COOL...WET WEATHER TO MUCH OF THE REGION THROUGH TUESDAY. DRY
AND WARMER WEATHER RETURNS WEDNESDAY WITH PATCHY VALLEY FOG POSSIBLE.

&&

.DISCUSSION...
SATELLITE AND RADAR LOOPS SHOW THE UPPER-LEVEL LOW CENTERED OVER
WESTERN KINGS/NORTHWESTERN KERN COUNTY THIS MORNING...ALTHOUGH A
SERIES OF VORTICITIES REVOLVING AROUND THE LOW CENTER GIVE THE LOW
AN ELONGATED /WEST-EAST/ APPEARANCE AND MAKE THE EXACT POSITION HARD
TO DEFINE. THE CYCLONIC FLOW AROUND THE LOW HAS RESULTED IN AN
EASTERLY FLOW OVER THE NORTHERN HALF OF THE WFO HANFORD WARNING/
FORECAST AREA...AND ONE SHOWER THAT DEVELOPED OVER NORTHWESTERN
FRESNO COUNTY HAD MOVED INTO SAN BENITO COUNTY. OVER THE SOUTHERN
HALF OF THE FORECAST AREA...THE FLOW IS PREDOMINANTLY SOUTHERLY AND
SHOWERS AND ISOLATED THUNDERSTORMS OVER SANTA BARBARA THROUGH LOS
ANGELES COUNTIES ARE PUSHING NORTHWARD TOWARD KERN COUNTY AS OF
1015Z /0215 PST/ THIS MORNING. HAVE THEREFORE ADDED A SLIGHT
CHANCE OF THUNDERSTORMS TO THE SOUTHEASTERN KERN COUNTY DESERT FOR
TODAY.

THE UPPER-LEVEL LOW IS FORECAST TO BE OVER POINT CONCEPTION BY 18Z
/1000 PST/ THIS MORNING...AND THEN STALL THERE THE REST OF TODAY.
THE MODELS ARE IN GOOD AGREEMENT WITH THE LOW ELONGATING ACROSS
CENTRAL CALIFORNIA THIS AFTERNOON. IN TERMS OF INSTABILITY
PARAMETERS...THE 06Z NAM-12 HAS A PEAK SURFACE COMPUTED CAPE OF 480
JOULES/KG OVER KINGS COUNTY AT 21Z /1300 PST/ THIS AFTERNOON WITH A
SURFACE COMPUTED LIFTED INDEX OF -2.8...500-MB TEMPERATURE OF 27.6 C
AND 850-MB THETA-E OF 297.6 K. SPC HAS MOST OF THE WFO HANFORD
WARNING/FORECAST AREA UNDER A MARGINAL RISK FOR THUNDERSTORMS TODAY
AND THIS LOOKS ON TRACK.

WITH THE SOUTHERLY FLOW OVER THE TEHACHAPI AND SAN EMIGDIO MOUNTAINS
THIS MORNING...WARM AIR ADVECTION HAS KEPT THE SNOW LEVEL ABOVE THE
TEJON AND TEHACHAPI PASSES FOR NOW. HOWEVER...AS THE LOW DROPS SOUTH
TONIGHT AND THE FLOW SHIFTS...COLDER AIR WILL MOVE INTO THE MOUNTAINS
AND SNOW WILL FALL ON THE HIGHER POINTS OF THE PASSES.

THE NEXT SYSTEM IS CURRENTLY AN UPPER-LEVEL SHORT-WAVE OVER THE
QUEEN CHARLOTTE ISLANDS. THIS WAVE IS FORECAST TO DEEP AS IT DROPS
THROUGH BRITISH COLUMBIA THIS EVENING AND THROUGH THE PACIFIC
NORTHWEST OVERNIGHT. THE SHORT-WAVE WILL DEVELOP A LOW THAT IS
FORECAST TO BE WEST OF MONTEREY BAY BY 18Z MONDAY AND OFF POINT
CONCEPTION BY 00Z TUESDAY /1600 PST MONDAY/. THE TRACK OF THIS
SECOND SYSTEM IS VIRTUALLY IDENTICAL TO THE FIRST AND THE LOCATION OF
THE LOW ALONG THE CENTRAL COAST MONDAY AFTERNOON RAISES THE RISK OF
MORE THUNDERSTORMS OVER CENTRAL CALIFORNIA. HAVE FOLLOWED THE LEAD
OF NEIGHBORING OFFICES AND ADDED A SLIGHT CHANCE OF THUNDERSTORMS
TO THE CENTRAL/SOUTHERN SAN JOAQUIN VALLEY...THE FOOTHILLS AND THE
SOUTHEASTERN KERN DESERT BEGINNING AT 18Z MONDAY.

THE UPPER-LEVEL LOW IS FORECAST TO BE OFF SAN DIEGO BY 00Z
WEDNESDAY. PRECIPITATION WILL TAPER OFF MONDAY NIGHT AND TUESDAY
MORNING...AND BE LIMITED TO THE SOUTHERN SIERRA NEVADA TUESDAY
AFTERNOON.

AN AMPLIFYING UPPER-LEVEL EAST-PACIFIC RIDGE IS FORECAST TO BUILD
INTO CALIFORNIA TUESDAY NIGHT/WEDNESDAY. AS THE RIDGE MOVES OVER THE
SAN JOAQUIN VALLEY...COULD SEE PATCHY FOG DEVELOP AS THE INVERSION
FORMS OVER THE VALLEY FLOOR. THIS IS NOT UNEXPECTED AS HISTORICALLY
THE TULE FOG SEASON CAN RUN THROUGH THE FIRST WEEK OF MARCH.

&&

.AVIATION...
OVER THE SOUTHERN SIERRA AND ADJACENT FOOTHILLS...AREAS OF IFR
AND MOUNTAIN OBSCURATIONS IN SHOWERS. LOCAL MVFR IN HEAVIER
SHOWERS IN THE SAN JOAQUIN VALLEY AND KERN COUNTY DESERT...AND IFR
POSSIBLE WITH ISOLD TSTORMS THROUGH 06Z MONDAY. VFR CONDITIONS CAN
BE EXPECTED ELSEWHERE OVER THE CENTRAL CALIFORNIA INTERIOR DURING
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.

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 03-01       79:1975     50:1951     59:1986     28:1888
KFAT 03-02       82:1921     48:1976     57:1986     26:1953
KFAT 03-03       80:1994     45:1976     55:1905     26:1966

KBFL 03-01       86:2009     48:1919     59:1920     26:1907
KBFL 03-02       87:1926     50:1919     57:2009     28:1907
KBFL 03-03       84:1987     47:1976     55:1930     20:1917

&&

.HNX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 4 AM PST MONDAY FOR THE KERN COUNTY
MOUNTAINS /CAZ095/.

&&

$$

PUBLIC...SANGER
AVN/FW...DCH
SYNOPSIS...SANGER

WEATHER.GOV/HANFORD



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