000
FXUS63 KJKL 191440 AAB
AFDJKL

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON KY
1040 AM EDT WED JUN 19 2013

.UPDATE...
ISSUED AT 1040 AM EDT WED JUN 19 2013

LOW STRATUS DECK NEAR WHAT IS LEFT OF THE BOUNDARY THAT DROPPED INTO
THE COMMONWEALTH ON TUE EVENING HAS BEEN SLOW TO MIX INTO CU ACROSS THE
MIDDLE OF THE CWA FROM ESTILL COUNTY EAST TO NEAR JKL AND THEN
FURTHER EAST INTO THE BIG SANDY REGION. CONTINUED HEATING SHOULD
EVENTUALLY CAUSE THIS TO LIFT INTO CU AROUND MIDDAY. A RATHER
EXTENSIVE CU FIELD SHOULD DEVELOP BY EARLY AFTERNOON AND A STRAY
SPRINKLE OR TWO CANNOT BE COMPLETELY RULED OUT. HOURLY GRIDS WERE
ADJUSTED BASED ON RECENT OBSERVATIONS AND SAT IMAGERY.

UPDATE ISSUED AT 724 AM EDT WED JUN 19 2013

WILL UPDATE FOR OBSERVED CONDITIONS BLENDING INTO THE 1ST PERIOD
FORECAST. NO SUBSTANTIAL CHANGES ARE PLANNED.

&&

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 400 AM EDT WED JUN 19 2013

THE REMNANT OF A DISSIPATING COLD FRONT WAS SLOWLY SETTLING SOUTH
OVER THE AREA DURING THE NIGHT. AS IT DROPS TO OUR SOUTH TODAY IT WILL
STALL AND DISSOLVE. HIGH PRESSURE BEHIND THE FRONT WILL MOVE FROM THE
GREAT LAKES TODAY TO A POSITION JUST OFF THE NEW ENGLAND COAST ON
THURSDAY AFTERNOON. IT WILL SEND SOMEWHAT DRIER AIR INTO OUR LOCAL
AREA...ESPECIALLY OUR NORTHEASTERN COUNTIES. THIS SHOULD PREVENT
SHOWERS AND THUNDERSTORMS FOR THE MOST PART. WOULD NOT ENTIRELY RULE
OUT PRECIPITATION TODAY OR THURSDAY NEAR THE TENNESSEE BORDER...WHERE
THE HIGHEST DEW POINTS WILL LINGER. HOWEVER...WITH DRY AIR ALOFT AND
A LACK OF SIGNIFICANT UPPER SUPPORT...HAVE PLACED THE POP BELOW THE
20 PERCENT THRESHOLD FOR INCLUSION IN THE FORECAST.

.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 420 AM EDT WED JUN 19 2013

THE PERIOD WILL START WITH A 500MB TROUGHING PATTERN ACROSS THE
SOUTHEAST...RIDGING OVER THE SOUTH CENTRAL...AND TWO STRONG LOW
PRESSURE CENTERS OVER THE NW AND OVER NE CANADA. KY WILL FIND ITSELF
IN AN AREA OF DIFFLUENCE IN THIS PATTERN...AS THE TROUGH CONTINUES
EASTWARD ALONG WITH THE SURFACE FRONT AND MAIN AREA OF
PRECIPITATION. EXPECT RIDGING TO START SLIDING EASTWARD ACROSS THE
OHIO VALLEY DURING THE DAY...WHILE A SHORTWAVE BEGINS TO DEVELOP ON
THE WINDWARD SIDE OF THE TROUGH. WITH DAYTIME HEATING AND A WARM
MOIST ENVIRONMENT IN PLACE...THIS COULD VERY WELL TRIGGER SOME
AFTERNOON SHOWERS AND THUNDERSTORMS. OBVIOUSLY THIS FAR OUT IN THE
FORECAST...MODELS START TO LOSE AGREEMENT ON SMALLER SCALE
CONVECTIVE FEATURES...BUT THEY ALL DO SEEM TO PINPOINT A BETTER AREA
OF CONVECTION OVER THE FAR EAST AND THE SOUTH. AS DAYTIME HEATING
SUBSIDES...SO WILL CONVECTION...AND THE RIDGING PATTERN WILL ONCE
AGAIN TAKE OVER.

FOR SATURDAY AND SUNDAY...A SHORTWAVE WILL DEVELOP AND TRAVERSE
ZONAL FLOW TO THE NORTH OF THE REGION. THIS WILL PRODUCE A BROAD
AREA OF PRECIPITATION...WHICH IF THE MODELS HOLD TRUE...SHOULD PASS
MAINLY TO OUR NORTH. THE OUTLIER IN THIS IS THE ECMWF...WHOSE
SOLUTION /WHILE NOT NECESSARILY WRONG/ BRINGS THE PRECIP FARTHER
SOUTH...POSSIBLY GRAZING THE FAR NORTHERN KY COUNTIES. THE GFS TRIES
TO SPAWN CONVECTION ALONG THE NORTHERN COUNTIES AS WELL...AWAY FROM
THE MAIN AREA OF PRECIPITATION. HOWEVER...THIS FAR OUT...TRYING TO
PINPOINT CONVECTIVE ACTIVITY WHEN OTHER MODELS ARE NOT PICKING UP ON
IT MAKES CONFIDENCE IN OCCURRENCE VERY LOW. WENT WITH SLIGHT CHANCES
AT THIS TIME TO ACCOMMODATE BOTH IDEAS...AS WELL AS KEPT SLIGHT
CHANCE POPS IN THE SOUTHEAST...SINCE MOIST ATMOSPHERE AND WARM TEMPS
MEETING THE UPSLOPE OF THE MOUNTAINS COULD BE ENOUGH TO SPAWN SOME
CONVECTIVE ACTIVITY IN THIS AREA AS WELL.

MODELS CONTINUE TO DIVERGE IN SOLUTIONS FOR THE REMAINDER OF THE
FORECAST PERIOD /MONDAY THROUGH WEDNESDAY/ AS ANOTHER COUPLE OF
SHORTWAVES PASS TO THE SOUTH. WILL CONTINUE WITH A CONSENSUS OF
MODELS FOR THIS TIME PERIOD. THERE WILL BE LITTLE CHANGE IN HIGH AND
LOW TEMPERATURES THROUGH THE EXTENDED AS WELL...REMAINING IN THE MID
TO UPPER 80S FOR HIGHS...AND MID TO UPPER 60S FOR LOWS.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 724 AM EDT WED JUN 19 2013

FOG AND LOW CLOUDS WERE BRINGING IFR TO PORTIONS OF THE AREA...
ESPECIALLY VALLEYS IN THE SE PART OF THE STATE. MEANWHILE...VFR WAS
ALSO PRESENT...ESPECIALLY ON RIDGES IN THE FAR NW. THE FOG AND LOW
CLOUDS WILL DISSIPATE THIS MORNING...LEAVING VFR ACROSS THE ENTIRE
AREA UNTIL LATE TONIGHT. VALLEY FOG IS THEN EXPECTED TO DEVELOP
OVERNIGHT AND BRING LOCALIZED IFR...BUT PROBABLY NOT AFFECTING TAF
SITES. WINDS WILL BE LIGHT THROUGH THE PERIOD.


&&

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

$$

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