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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS63 KJKL 201706
AFDJKL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
106 PM EDT MON MAY 20 2013

.UPDATE...
ISSUED AT 1223 PM EDT MON MAY 20 2013

WHILE A FEW MORE SHOWERS MAY CLIP THE EXTREME EASTERN END OF PIKE
COUNTY...THE MAIN BAND OF CONVECTION HAS FINALLY SHIFTED EAST. AM
STILL RELUCTANT TO REMOVE ALL CHANCES OF RAIN FOR THIS AFTERNOON AND
WILL LEAVE THE CURRENT LOW PROBABILITIES IN PLACE FOR THE EAST AND
CENTRAL AREAS. THE 14Z HRRR HAS TRENDED TOWARDS SOME ISOLATED
CONVECTION FOR THIS AFTERNOON. IT SHOULD ALSO BE NOTED THE HRRR WAS
MUCH TOO QUICK TO MOVE THE CONVECTIVE BAND OVER ERN KY AND WV EAST
THIS MORNING. HAVE UPDATED NDFD FOR LATEST TRENDS AND WILL UPDATE ZFP
SHORTLY.

UPDATE ISSUED AT 1036 AM EDT MON MAY 20 2013

PERSISTENT CONVECTION CONTINUES TO AFFECT FAR EASTERN PIKE COUNTY. IN
FACT CONVECTION CONTINUES TO DEVELOP UPSTREAM ALL THE WAY TO EAST OF
COLUMBUS OH. THE GOOD NEWS IS THAT THE BOUNDARY FOCUSING THIS
CONVECTION IS GRADUALLY SHIFTING EAST...AND WILL BE EAST OF PIKE
COUNTY BY EARLY AFTERNOON. THE RAINFALL RATES HAVE ALSO BEEN LESS THE
PAST COUPLE OF HOURS. FOR EXAMPLE THE PHELPS IFLOWS GAGE IS REPORTING
0.71 SINCE THE EVENT BEGAN...WITH 0.51 OF THIS FALLING BETWEEN 09Z
AND 10Z.

ONCE THE BAND OF CONVECTION IN THE FAR EAST MOVES OUT OF THE
STATE...THE 12Z HRRR AND 12Z NAM SHOW NO RAIN OVER OUR AREA FOR THE
REST OF THE DAY. HOWEVER HAVE ELECTED TO LEAVE THE LOW CHANCE
PROBABILITIES OF RAIN FOR THE EAST AND CENTRAL PART OF THE FORECAST
AREA. MORNING SOUNDINGS ARE QUITE UNSTABLE WITH LI OF -8 AT ILN AND -6
AT OHX. AM CONCERNED THAT BOUNDARIES LEFT FROM THIS MORNINGS
CONVECTION COULD FOCUS SOME ADDITIONAL CONVECTION LATER THIS
AFTERNOON.

HAVE UPDATED NDFD FOR LATEST HOURLY TRENDS BUT ZFP DOES NOT NEED AN
UPDATE AT THIS TIME.

UPDATE ISSUED AT 727 AM EDT MON MAY 20 2013

CONVECTION HAS BEEN PERSISTENT ACROSS FAR SOUTHEASTERN KENTUCKY EARLY
THIS MORNING. THE LATEST NAM AND SREF CONTINUE TO SHOW SOME ACTIVITY
LINGERING INTO THE MID-MORNING HOURS. AS SUCH...WILL ALLOW FOR HIGHER
POPS IN THE FAR EAST. THE FOG HAS ALSO BEEN MORE SPOTTY THIS
MORNING...SO WILL DOWNPLAY THIS INTO THE MID-MORNING HOURS.

&&

.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 351 AM EDT MON MAY 20 2013

A LEFTOVER OUTFLOW BOUNDARY MOVING THROUGH SOUTHEASTERN KENTUCKY HAS
SPARKED A BROKEN LINE OF SHOWERS AND THUNDERSTORMS...WITH EVEN A
STRAY SHOWER CURRENTLY AFFECTING THE JKL OFFICE. WILL INCLUDE SOME
ISOLATED POPS EARLY THIS MORNING GIVEN THESE TRENDS...ALTHOUGH THE
MAIN LINE LOOKS TO EXIT THE SOUTHEAST BETWEEN 4 AND 4:30 AM.

OTHERWISE...UPPER LEVEL RIDGING WILL BE BUILDING IN THROUGH THE DAY
TODAY ACROSS THE COMMONWEALTH IN RESPONSE TO A DEEP TROUGH SLOWLY
NUDGING EAST ACROSS THE PLAINS. THIS WILL RESULT IN MORE ISOLATED
CONVECTIVE COVERAGE. DESPITE A LACK OF DEEPER MOISTURE...THE LATEST
FORECAST SOUNDINGS SHOW QUITE A BIT OF INSTABILITY...SO ANYTHING THAT
DOES INITIATE COULD BE STRONG. WILL HIGHLIGHT THIS IN THE HWO. HIGHS
WILL TOP OUT IN THE MID 80S FOR MOST.

SKIES WILL CLEAR OUT TONIGHT...ALLOWING FOR SOME FOG ONCE AGAIN. LOWS
WILL BOTTOM OUT IN THE LOW TO MID 60S. ON TUESDAY...THE PLAINS TROUGH
WILL BE GETTING A LITTLE CLOSER AND ANY CAPPING WILL BE WEAK. WILL
ALLOW FOR SCATTERED CONVECTION DURING THE AFTERNOON HOURS...WITH SOME
OF THIS POSSIBLY BECOMING STRONG ONCE AGAIN...ESPECIALLY NEAR THE
BLUEGRASS COUNTIES. HIGHS WILL SOAR INTO THE UPPER 80S...THREATENING
RECORD HIGHS FOR THE DATE AT JKL AND LOZ.

.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 425 AM EDT MON MAY 20 2013

THE PERIOD SHOULD BEGIN RATHER ACTIVE AS AN UPPER LEVEL LOW INITIALLY
OVER THE PLAINS/MO VALLEY REGION AND A SHORTWAVE TROUGH EXTENDING TO
ITS SOUTH APPROACHES THE MS VALLEY AND LOWER OH VALLEY REGION TUE
NIGHT INTO EARLY ON WED. THE ASSOCIATED SFC LOW SHOULD DEEPEN A BIT
AS IT TRACKS TOWARD THE WESTERN GREAT LAKES REGION TUE NIGHT INTO
WED. A LOW LEVEL JET SHOULD TRANSPORT RATHER ABUNDANT MOISTURE INTO
THE REGION WITH PW FORECAST TO INCREASE TO AROUND 1.4 TO 1.5 INCHES.
THE UPPER LEVEL LOW WILL GRADUALLY OPEN UP WITH A SHORTWAVE TROUGH
WORKING ACROSS EASTERN KY LATER ON WED INTO WED NIGHT. MODELS BRING
SOME INCREASING WINDS ALOFT INTO THE AREA AT THAT POINT...THOUGH THE
STRONGER SHEAR SHOULD REMAIN TO OUR NORTH. THE UPPER LEVEL LOW SHOULD
WORK SLOWLY EAST SOUTHEAST REACHING THE UPPER OH VALLEY REGION AND
MID ATLANTIC STATES THU NIGHT INTO FRIDAY. AT THE SFC...THE LOW WILL
TRACK INTO THE EASTERN GREAT LAKES WED NIGHT AND THEN NORTHEAST
ACROSS THE ST LAWRENCE VALLEY WITH THE TRAILING COLD FRONT CROSSING
EASTERN KY ON THU.

THERE WILL PROBABLY BE A LULL IN CONVECTION FOR A TIME ON TUE NIGHT
BETWEEN RATHER DIURNALLY DRIVEN CONFECTION FROM TUE AND RESURGENCE
LIKELY TO OUR WEST AND SOUTHWEST WITH STRENGTHENING LOW LEVEL JET AND
APPROACHING UPPER LEVEL SHORTWAVE LATE TUE NIGHT. MODEL FORECAST
INSTABILITY AND SHEAR ALONG WITH TIMING OF MODELS BRINGING PREFRONTAL
CONVECTION INTO EASTERN KY POINT TOWARD THE POSSIBILITY OF STRONG TO
LOCALLY SEVERE STORMS POSSIBLE ANYWHERE IN THE CWA THOUGH THE NORTH
WILL BE CLOSER TO THE STRONGER LOW LEVEL JET CORE AS HIGHLIGHTED BY
SPC DAY 3 OUTLOOK. THE POTENTIAL FOR LOCALLY HEAVY RAIN AND SOME OF
THE STORMS TO BECOME STRONG WILL BE HIGHLIGHTED FOR WED IN THE HWO.
LIKELY POPS WERE USED FOR WED IN LINE WITH THE MODEL CONSENSUS AND
MOS GUIDANCE. THE MAV NUMBERS CONTINUE TO APPEAR TOO WARM UNLESS
THERE ENDS UP BEING LITTLE CLOUD COVER ON WED AND HIGH TEMPS WERE
TRENDED LOWER TOWARD MODEL CONSENSUS/MET GUIDANCE.

POPS WERE CONTINUED BEHIND THE BOUNDARY INTO FRI AS THE UPPER LEVEL
SYSTEM GRADUALLY WORKS ACROSS THE REGION. THE EXTENDED MODELS
APPEAR TO BE A IN A BIT BETTER AGREEMENT WITH THE UPPER LEVEL
LOW/SHORTWAVE TROUGH TO MOVE ACROSS THE AREA THU INTO FRI.
HOWEVER...LATER IN THE PERIOD THE GFS MAY BE SUFFERING FROM SOME
CONVECTIVE FEEDBACK ISSUES ACROSS THE PLAINS TO WESTERN GREAT LAKES
REGION SAT INTO SUN WHILE THE ECMWF CONTINUES TO DEVELOP CONVECTION
WITH DISTURBANCES IN NW FLOW INTERACTING WITH A WARM FRONT ADVANCING
TOWARD THE LOWER OH VALLEY REGION LATE IN THE PERIOD. THE EXTENDED
GRID LOAD MODEL CONSENSUS HAD SLIGHT CHANCE TO CHANCE POPS FOR SUN
AND THIS WAS GENERALLY FOLLOWED.

&&

.AVIATION...
-- Changed Discussion --
(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 106 PM EDT MON MAY 20 2013

EXTENSIVE FIELD OF CU AND SC IS ACROSS THE AREA. SKY CONDITIONS ARE
QUITE VARIABLE RANGING FROM SCT TO OVC...WITH CEILINGS RANGING FROM
LESS THAN 3K FEET TO AROUND 5K FEET. CEILINGS WILL BE LIFTING
THROUGH THE REMAINDER OF THE AFTERNOON...WITH CLOUDS ALSO SCATTERING
OUT LATE. AS SUCH VFR CONDITIONS WILL PREVAIL INTO THE NIGHT. WITH UPPER
LEVEL HIGH PRESSURE BUILDING INTO THE AREA THUNDERSTORMS WILL BE MUCH
LESS LIKELY FOR THE REMAINDER OF THE DAY...ALTHOUGH AN ISOLATED
SHOWER OR THUNDERSTORM CANNOT BE RULED OUT IN THE CENTRAL AND EASTERN
PART OF THE FORECAST AREA. MVFR FOG CAN BE EXPECTED TOWARDS DAWN ON
TUESDAY...BUT THIS WILL BE VERY SHORT LIVED.
-- End Changed Discussion --

&&

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

$$

UPDATE...SBH
SHORT TERM...GEOGERIAN
LONG TERM...JP
AVIATION...SBH