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000
FXUS63 KJKL 171120 AAA
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON KY
720 AM EDT MON JUN 17 2013

.UPDATE...
ISSUED AT 720 AM EDT MON JUN 17 2013

A FEW SHOWERS HAVE POPPED UP ACROSS CENTRAL KY...AS WELL AS ONE JUST
EAST OF LONDON. FORECASTED POPS SEEMED TO JIVE WELL WITH THIS
ISO/SCT SHOWER DEVELOPMENT OVER THE CWA...WITH THE BETTER POTENTIAL
OVER THE SOUTHERN HALF...INCREASING THIS AFTERNOON UNDER BEST
INSTABILITY. ONLY UPDATE WAS TO INCLUDE LATEST OBSERVATIONS WITHIN
THE FORECAST GRIDS.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 530 AM EDT MON JUN 17 2013

.SHORT TERM...

500MB SHORTWAVE OVER THE SOUTHERN PLAINS SPAWNED A LARGE AREA OF
CONVECTION OVERNIGHT LAST NIGHT...AND WILL CONTINUE TO DIVE SSE
ALONG THE ZONAL FLOW TONIGHT/TUESDAY MORNING. AS THIS AREA OF
CONVECTION EXPANDED THROUGHOUT THE NIGHT...CLOUD COVER BEGAN TO
DEVELOP AND EXPAND ACROSS MUCH OF KENTUCKY IN RESPONSE TO AN INFLUX
OF MOISTURE AHEAD OF THE SYSTEM. UNFORTUNATELY...THIS CUT OFF BEST
FOG POTENTIAL AS WAS EXPECTED WITH EVENING UPDATE. MORNING FORECAST
HAS A REDUCTION IN THE IMPACTS OF FOG ACROSS THE REGION...WITH
PATCHY TO AREAS STILL POSSIBLE ACROSS MUCH OF THE VALLEYS.

OTHERWISE...MAIN FOCUS TURNS TO CONVECTION AS THE SHORTWAVE NEARS
THE AREA TUESDAY. AS IT APPROACHES...A WEAK SURFACE FRONT WILL
REMAIN STATIONARY JUST NORTH OF THE REGION. WINDS REMAIN S/SW ACROSS
KY AHEAD OF THIS FRONT...MAKING A SHARP VEERING PATTERN IN THE MID
LEVELS BY EARLY AFTERNOON. IN ADDITION TO LAPSE RATES OVER THE AREA
IN THE 6.5C RANGE...LATEST NAM FORECAST SOUNDINGS SUPPORT POTENTIAL
FOR SOME STRONG CONVECTIVE DEVELOPMENT. MOISTURE IN THE LOW/MID
LEVELS AND DRY ALOFT...DAYTIME HEATING WILL MAKE IT EASY TO TAP INTO
A VERY DECENT POOL OF INSTABILITY /CAPE VALUES AROUND 2800 J/KG BY
18Z/. WITH SUCH AN ENVIRONMENT IN PLACE...EXPECT INDIVIDUAL CELLS TO
DEVELOP ACROSS THE CWA RATHER THAN A WIDESPREAD AREA OF PRECIP.
UNTIL CELLS DEVELOP...EXACT COVERAGE/TIMING/LOCATION IS STILL
UNCERTAIN...SO TRIED NOT TO GO LIKELY AT THIS TIME.

ACTUAL SHORTWAVE AND BEST PRECIP WILL THEN BEGIN TO AFFECT THE JKL
CWA BY EARLY TUESDAY MORNING. BEST MOISTURE WILL SLIDE TO OUR
SOUTH...BUT STILL EXPECT A FAIRLY WIDESPREAD SWATH OF RAIN AND
EMBEDDED THUNDERSTORMS TO SPREAD ACROSS PORTIONS OF THE CWA.
FORECAST SOUNDINGS ARE MUCH MORE SATURATED BY 15Z TUESDAY...AND
THOUGH INSTABILITY IS PRESENT...CONDITIONS DON/T LOOK QUITE AS
FAVORABLE AS TODAY. SOUNDINGS THEN SHOW A GOOD INFLUX OF DRY AIR BY
WED 0Z AS SHORTWAVE CONTINUES OFF TO THE SE AND HIGH PRESSURE
FINALLY BEGINS TO TAKE HOLD.

.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 530 AM EDT MON JUN 17 2013

.LONG TERM...TUESDAY THROUGH SUNDAY

THE PATTERN LOOKS RATHER MURKY...WITH SYSTEMS THAT ARE NOT WELL
DEFINED AT THE START OF THE PERIOD. A BROAD UPPER TROUGH SHOULD BE
OVER THE EASTERN CONUS...WITH A WEAK COLD FRONT SINKING SOUTH
THROUGH THE OHIO VALLEY. ONGOING CONVECTION FROM THE DAY MAY LINGER
INTO THE NIGHT...BUT SHOULD DIMINISH AS HEATING IS LOST AND SLIGHTLY
COOLER/DRIER AIR BEGINS TO ARRIVE FROM THE NORTH. THE CHANGE IN AIR
MASS SHOULD PREVENT DEEP CONVECTION ON WEDNESDAY...WITH WARMING MID
LEVEL TEMPS ADDING TO THE SUPPRESSION ON THURSDAY.

OUR LOW LEVEL FLOW IS EXPECTED TO TURN BACK TOWARD THE SOUTH FRIDAY
THROUGH THE WEEKEND...BRINGING AN INCREASE IN MOISTURE. HOWEVER...AT
THE SAME TIME THE EASTERN CONUS TROUGH WILL BE GETTING REPLACED BY
RIDGING BUILDING EAST FROM THE CENTRAL CONUS. FORECAST SOUNDINGS DO
NOT LOOK PARTICULARLY FAVORABLE FOR DEEP CONVECTION. HOWEVER...MID
LEVEL TEMPS ARE SHOWN TO BE SLIGHTLY COOLER OVER OUR SOUTHEAST
COUNTIES. COMBINED WITH THE DIFFERENTIAL HEATING OF HIGHER TERRAIN
THERE...IT IS ENOUGH TO WARRANT SLIGHT CHANCE POPS FRIDAY THROUGH
SUNDAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 720 AM EDT MON JUN 17 2013

FOG IS CONTINUING TO MIX OUT ACROSS THE REGION...SO WENT AHEAD AND
REMOVED FROM TAF SITES. THE EXCEPTION IS KJKL...WHERE A FEW MINUTES
OF CONTINUED LOWER VIS MAY BE POSSIBLE BEFORE CONDITIONS CLEAR. THE
MAIN CHANGES TO PREVIOUS FORECAST ARE THE TIMING AND CERTAINTY OF
CONVECTION TODAY AND TONIGHT. WITH A THUNDERSTORM ALREADY IMPACTING
KLOZ...FORECAST SOUNDINGS LOOK SUPPORTIVE FOR CONTINUED CONVECTIVE
DEVELOPMENT THROUGHOUT THE DAY...WITH LIKELY/S POSSIBLE FOR KLOZ AND
KSME BY TONIGHT. WENT AHEAD AND PUSHED UP MENTION OF VCTS AT ALL TAF
SITES AS A RESULT...THEN WENT WITH PREVAILING TSRA ONCE LIKELY POPS
COME INTO PLAY AT KLOZ AND KSME. KJKL SHOULD SEE CHANCE POPS THROUGHOUT
THE DAY WITH UNCERTAINTY ON EXACT LOCATION OF SET UP...SO JUST WENT
WITH VCTS AT THIS TIME. UPDATES WILL NEED TO BE MADE AS CONVECTION
DEVELOPS AND POSES A THREAT TO TAF SITES. UNDER
THUNDERSTORMS...EXPECT VISIBILITIES TO BE REDUCED...ALONG WITH
STRONGER WINDS AND THE POTENTIAL FOR HAIL DEVELOPMENT THIS AFTERNOON.



&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JMW
SHORT TERM...JMW
LONG TERM...HAL
AVIATION...JMW