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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS63 KJKL 182316
AFDJKL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
716 PM EDT TUE JUN 18 2013

.UPDATE...
ISSUED AT 552 PM EDT TUE JUN 18 2013

COLD FRONT SAGGING SOUTH TOWARDS THE OHIO RIVER. SCATTERED SHOWERS
AND THUNDERSTORMS ARE MARKING THE FRONT. TIMING HAS THE FRONT INTO
OUR NRN KY COUNTIES AROUND 7 PM. CONVECTION SHOULD EASE AFTER SUNSET
SO WILL CONTINUE SCT SHOWERS BUT DECREASE ACTIVITY TO JUST ISOLATED
THUNDERSTORMS THROUGH AT LEAST MIDNIGHT WITH THE FRONT LOSING ALL
CONVECTIVE IDENTITY AFTER MIDNIGHT. STILL COULD BE A FEW SHOWERS...
HOWEVER THE THE GREATEST THREAT AFTER MIDNIGHT WILL COME FROM THE
AREAS OF FOG AS THE VALLEYS COOL. HAVE UPDATED GRIDS AND ZONES TO
REFLECT NEW FORECAST.

&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 300 PM EDT TUE JUN 18 2013

NOT MUCH TO SPEAK OF IN THE SHORT TERM PORTION OF THE FORECAST. THE
MODELS ALL AGREE THAT A WEAK DISTURBANCE IN THE MIDDLE ATMOSPHERE
WILL MAKE ITS WAY SOUTHWARD OUT OF THE UPPER GREAT LAKES REGION
THROUGH LATE TONIGHT. ISOLATED TO POSSIBLY SCATTERED RAIN SHOWERS
WILL BE POSSIBLE AS THIS DISTURBANCE PASSES THROUGH THE OHIO VALLEY
AND ON TO THE MID ATLANTIC REGION. IT APPEARS THERE WILL NOT BE ENOUGH
INSTABILITY AVAILABLE TO SPARK THUNDERSTORMS...SO THUNDER WAS LEFT
OUT OF THE FORECAST FOR THE OVERNIGHT PERIOD. TEMPERATURES WILL BE
RUNNING AROUND NORMAL THROUGH TOMORROW NIGHT...WITH OVERNIGHT LOWS IN
THE LOWER 60S AND HIGHS ON WEDNESDAY AROUND 80. WINDS WILL REMAIN
LIGHT THROUGHOUT THE PERIOD. CLOUDS WILL GRADUALLY BREAKUP
OVERNIGHT...AND WITH LIGHT TO CALM WINDS EXPECTED...AND TAKING INTO
ACCOUNT THE AMOUNT OF RAINFALL THE AREA HAS RECEIVED THE PAST FEW
DAYS...FOG FORMATION WILL BE A DISTINCT POSSIBILITY IN THE VALLEYS OF
EASTERN KENTUCKY. THE BEST TIME FOR FOG WILL BE BETWEEN 7 AND 12Z.
VALLEY FOG WILL BE POSSIBLE AGAIN WEDNESDAY NIGHT AS EVEN FEWER
CLOUDS AND CALM WINDS WILL BE ON TAP. THE FOG COULD BE DENSE AT
TIMES.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 345 PM EDT TUE JUN 18 2013

UPPER LEVEL RIDGING SHOULD BUILD FROM THE SOUTHERN PLAINS ACROSS THE
SOUTHEASTERN CONUS THROUGH THE PERIOD LEADING THE REGION IN THE WARM
SECTOR. HIGH PRESSURE AT THE SFC INITIALLY FROM THE MID ATLANTIC
COAST RIDGING INTO THE SOUTHEASTERN CONUS WILL ALSO REMAIN IN PLACE.
A FEW DISTURBANCES WORKING AROUND THE RIDGING AND DAYTIME HEATING
SHOULD LEAD TO MAINLY DIURNAL CHANCES FOR CONVECTION THROUGH THE
PERIOD...ESPECIALLY AS LOW LEVEL MOISTURE INCREASES BY THE LATTER
HALF OF THE PERIOD.

GENERALLY ISOLATED POPS WERE USED NEAR THE VA AND TN BORDERS WHERE
DIFFERENTIAL HEATING OVER THE HIGHER TERRAIN ALONG THE VA BORDER AND
THE NORTHERN CUMBERLAND PLATEAU OR OUTFLOW BOUNDARIES FROM CONVECTION
FROM POTENTIAL CONVECTION OVER VA AND TN POSSIBLY MOVING INTO TN AND
VA BORDER AREAS MAY LEAD TO SOME STRAY CONVECTION. THE BULK OF THE
REGION SHOULD REMAIN DRY ON THU. ANY ACTIVITY SHOULD WANE ON THU
EVENING AND FOR THAT MATTER CONVECTION DURING THE ENTIRE EXTENDED
PERIOD SHOULD BE HIGHLY DIURNAL IN NATURE. BY FRI...WITH INCREASING
LOW LEVEL MOISTURE DIURNALLY DRIVEN CONVECTION COULD DEVELOP AS FAR
NORTH AS THE MTN PARKWAY OR INTERSTATE 64 CORRIDOR. AFTER THAT...WITH
MOISTURE INCREASING A BIT FURTHER...AND THE POTENTIAL FOR DISTURBANCES
PASSING BY TO OUR NORTH...ISOLATED TO SCATTERED CONVECTION CANNOT BE
COMPLETELY RULED OUT.

TEMPERATURES SHOULD MODERATE THROUGH THE PERIOD...WITH DAYTIME HIGHS
INITIALLY IN THE LOW TO MID 80S MODERATING TO THE MID TO UPPER 80S
THROUGH THE PERIOD. A FEW OF THE WARMER LOCATIONS COULD APPROACH THE
90 DEGREE MARK OVER THE UPCOMING WEEKEND PER SOME OF THE GUIDANCE.
THE GRID LOAD DATA PROVIDED A GOOD COMPROMISE BETWEEN THE GENERALLY
COLDER ECMWF MOS DATA AND THE RECENT MEX MOS GUIDANCE. AS LOW LEVEL
MOISTURE AND SFC DEWPOINTS INCREASE THROUGH THE PERIOD OVERNIGHT LOWS
WILL NOT BE AS COMFORTABLE WITH MID AND UPPER 60S ANTICIPATED BY THE
WEEKEND AND EARLY NEXT WEEK.

&&

.AVIATION...
-- Changed Discussion --
(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 715 PM EDT TUE JUN 18 2013

ANTICIPATING MOSTLY VFR CONDITIONS THROUGH ROUGHLY 7 OR 8Z TONIGHT.
WIDESPREAD CLOUD COVER WILL GRADUALLY PUSH EAST AND OUT OF THE AREA
AS THE EVENING WEARS ON...WITH SCATTERED TO AT TIMES BROKEN CLOUD
COVER AFFECTING THE TAF SITES UNTIL AFTER DARK. FEW TO SCATTERED
CLOUDS ARE THEN EXPECTED BETWEEN 0 AND 6Z. IN LIGHT OF THE AMOUNT OF
RAIN THAT HAS FALLEN ACROSS THE AREA SINCE YESTERDAY...AND WITH CALM
WINDS AND PARTLY CLOUDY SKIES EXPECTED OVERNIGHT...FOG FORMATION IS
ANTICIPATED AT THE TAF SITES. ALL WILL LIKELY SEE FOG BEGINNING
AROUND MIDNIGHT...WITH LIFR CONDITIONS EXPECTED BETWEEN 8 AND 12Z.
THE FOG SHOULD BE GONE AND CLOUDS SCATTERING OUT AROUND 13Z
WEDNESDAY.
-- End Changed Discussion --

&&

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

$$

UPDATE...DUSTY
SHORT TERM...AR
LONG TERM...JP
AVIATION...DUSTY