Area Forecast Discussion Issued by NWS Jackson, KY
000
FXUS63 KJKL 190625
AFDJKL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
225 AM EDT WED JUN 19 2013
.UPDATE...
ISSUED AT 225 AM EDT WED JUN 19 2013
UPDATE REMOVED PRECIP FROM FIRST PERIOD.
UPDATE ISSUED AT 1051 PM EDT TUE JUN 18 2013
RAIN SHOWERS CONTINUE TO PUSH INTO THE CWFA. LIGHTENING ACTIVITY HAS
ALMOST CEASED AS FCST. TIMING IN GRIDS IS NEARLY SPOT ON AND ONLY
MADE MINOR TWEAKS TO GRIDS TO REFLECT LATEST OBS. NO UPDATE TO ZONE
FCST REQUIRED. PRIMARY CONCERN IS FOR THE POTENTIAL FOR HEAVY RAIN AS
THE STORMS DIMINISH IN INTENSITY.
UPDATE ISSUED AT 849 PM EDT TUE JUN 18 2013
SHOWERS AND THUNDERSTORMS ARE BEGINNING TO PUSH INTO OUR NRN
COUNTIES. GRIDS HAVE BEEN UPDATED WITH LATEST OBS. PCPN FCST IS ON
TRACK WITH GRID FCST AND ZONE UPDATE IS NOT NECESSARY. WILL NEED TO
WATCH THE RAINFALL AS HEAVY RAIN MAY LEAD TO FLASH FLOODING QUICKLY
AFTER THE RAINFALL THAT OCCURRED ON MONDAY NIGHT.
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 DEW POINTS 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...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 225 AM EDT WED JUN 19 2013
LIGHT WINDS AND LINGERING MOISTURE AT THE SURFACE UNDERLYING DRYING
AND DECREASING CLOUDS ALOFT WILL LEAD TO AREAS OF FOG DEVELOPING
OVERNIGHT. IFR IS EXPECTED IN MOST LOCATIONS AROUND DAWN. FOG WILL
DISSIPATE IN THE MORNING...LEAVING VFR THROUGH THE REST OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...JP
AVIATION...HAL