575
FXUS63 KJKL 172030
AFDJKL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
430 PM EDT MON AUG 17 2026
KEY MESSAGES
- SHOWERS AND THUNDERSTORMS ARE POSSIBLE THROUGH THIS EVENING.
STRONG TO DAMAGING WIND GUSTS COULD OCCUR IN THE MOST INTENSE
STORMS, MAINLY NEAR THE TN AND VA BORDERS.
- A FLOOD WATCH IS IN EFFECT THROUGH THIS EVENING, MAINLY EAST OF
I-75. TORRENTIAL DOWNPOURS ON SATURATED GROUND POSE A RISK FOR
ISOLATED TO SCATTERED FLASH FLOODING.
- MAINLY DRY WEATHER RETURNS TUESDAY THROUGH WEDNESDAY, BEFORE
ANOTHER COLD FRONT BRINGS A RETURN OF THUNDERSTORMS WEDNESDAY
NIGHT OR THURSDAY.
- SOMEWHAT COOLER AND LESS HUMID WEATHER IS EXPECTED FOR THE
WEEKEND.
SHORT TERM
(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 430 PM EDT MON AUG 17 2026
LATE THIS AFTERNOON A COLD FRONT IS ON THE WESTERN EDGE OF THE
FORECAST AREA, PROGRESSING SOUTHEASTWARD BENEATH WEST NORTHWEST
FLOW ALOFT. INSTABILITY AHEAD OF THE FRONT VARIES ACROSS THE
FORECAST AREA, WITH EARLIER CLOUDS SOMEWHAT LIMITING HEATING IN
OUR NORTHERN COUNTIES. DEW POINTS ARE ALSO HIGHER IN THE SOUTH.
THIS IS RESULTING IN SPC MESOANALYSIS 100MB MIXED LAYER CAPE NEAR
3K J/KG BY THE TN BORDER, BUT ONLY AROUND 1.5K J/KG IN THE NORTH.
SHEAR IS NOT IMPRESSIVE, BUT SFC-3 KM OF 25-30 KTS IS ENOUGH TO
POSE A RISK OF SVR WX IN THE HIGHER INSTABILITY, AND SPC HAS A
WATCH FOR OUR SOUTHERNMOST COUNTIES. AS WET AS IT IS FROM RECENT
RAINS, A FLOOD WATCH REMAINS IN PLACE FOR MOST OF THE AREA.
HOWEVER, THE MOST INTENSE STORM POTENTIAL IN THE FAR SOUTH
FORTUNATELY DOES NOT LINE UP WITH WHERE FLOODING RAINS OCCURRED
YESTERDAY.
THE COLD FRONT WILL PROGRESS SOUTHEAST OUT OF THE FORECAST AREA
THIS EVENING, AND OUR THREAT OF SIGNIFICANT WX WILL END. MUCH
DRIER AIR WILL MOVE IN ALOFT, BUT ONLY MODESTLY DRIER IN THE
LOWEST LEVELS. WITH RATHER WEAK SURFACE FLOW, IT'S A SETUP FOR
FOG. HAVE HIT IT RATHER HARD IN THE FORECAST, AND THE SITUATION
WILL NEED TO BE WATCHED FOR THE NEED OF A SPS OR FOR ADVISORY
LATER TONIGHT.
DRIER AIR CONTINUES TO ARRIVE IN THE LOWER LEVELS ON TUESDAY, BUT
SOUNDINGS SHOW ENOUGH DESTABILIZATION FIRST TO POSSIBLY GIVE SOME
LIGHT SHOWERS AROUND MID DAY IN OUR SOUTHEAST. HOWEVER, THE
ATMOSPHERE LOOKS CAPPED TO DEEP CONVECTION AND THUNDER. ANY
SHOWERS DRY UP BY EVENING AND MAINLY CLEAR SKIES ARE THEN EXPECTED
THROUGH THE NIGHT. THE DRIER AIR MASS SHOULD ALLOW FOR LOWS IN
THE LOW-MID 60S Y DAWN ON WEDNESDAY-- COOLER THAN WE'VE SEEN FOR
A WHILE.
LONG TERM
(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 456 AM EDT MON AUG 17 2026
(AN UPDATED LONG TERM DISCUSSION WILL BE SENT SHORTLY.)
DRY WEATHER WILL PERSIST FOR MOST OF WEDNESDAY AS SURFACE HIGH
PRESSURE TRANSLATES THROUGH THE CENTRAL APPALACHIANS. IN ITS WAKE,
AN UPPER LEVEL TROUGH WILL BE DIGGING ACROSS THE GREAT LAKES AND
SUPPORTING A COLD FRONT SAGGING ACROSS THE OHIO VALLEY. BY
WEDNESDAY EVENING, THE FRONT WILL APPROACH EASTERN KENTUCKY AND
RAIN CHANCES WILL RETURN TO THE JKL CWA. OF NOTE, SOME MODELS
DEPICT AN ADDITIONAL SHORTWAVE TRAVERSING THE BASE OF THE TROUGH
(ROUGHLY CENTERED OVER THE OHIO VALLEY) AROUND THE TIME FRONTALLY
FORCED CONVECTION APPROACHES, OR PERHAPS SLIGHTLY BEFORE. THIS
ENHANCED MID LEVEL FLOW MAY ELEVATE SHEAR SOMEWHAT, AND DEPENDING
ON FRONTAL TIMING, INSTABILITY MAY ALSO BE ADEQUATE FOR STRONGER
STORMS, ALTHOUGH MODEL SPREAD REMAINS QUITE HIGH AT THIS TIME. ANY
RISK FOR SEVERE WEATHER (OR LACK THEREOF) REMAINS DEPENDENT ON
HOW THESE INGREDIENTS LINE UP, WITH OVERALL RISK LOOKING QUITE LOW
AT THIS TIME. MEANWHILE, A MOIST AIR MASS WILL BE IN PLACE AHEAD
OF THE FRONT, WITH LREF MEAN PW VALUES GENERALLY IN THE RANGE OF
1.6-1.7 IN (ROUGHLY 80TH PERCENTILE OR HIGHER COMPARED TO
CLIMATOLOGY). THIS, IN ADDITION TO POTENTIALLY ENHANCED CONVECTIVE
COVERAGE IF SHORTWAVE ENERGY INTERACTS WITH THE FRONT, COULD
ALLOW FOR AT LEAST ISOLATED INSTANCES OF FLASH FLOODING. AGAIN,
MODEL VARIABILITY REMAINS VERY HIGH AT THIS STAGE, BUT WPC HAS
ALREADY OUTLINED NORTHWESTERN PORTIONS OF JKL AREA IN A DAY 3
MARGINAL (LEVEL 1/4) RISK FOR EXCESSIVE RAINFALL ON WEDNESDAY, AND
AN ADDITIONAL DAY 4 MARGINAL RISK ON THURSDAY AS THE SYSTEM SAGS
SOUTH. GUIDANCE DOES SUGGEST THE FRONT WILL SLOW AS IT PASSES
THROUGH THE SOUTHERN PORTION OF OUR AREA AND INTO TENNESSEE.
EXACTLY HOW QUICKLY THIS BOUNDARY PROGRESSES IS STILL A SOURCE OF
UNCERTAINTY, BUT RAIN CHANCES HAVE BEEN MAINTAINED THROUGH
THURSDAY TO ACCOUNT FOR THIS SLOWING MOTION. ANY HYDROLOGICAL
CONCERNS WILL ALSO BE DEPENDENT ON THE SPEED OF THIS FRONTAL
PASSAGE IN ADDITION TO THE EXTENT OF CONVECTIVE COVERAGE.
FOLLOWING THE FRONTAL PASSAGE, TROUGHING WILL CONTINUE TO
AMPLIFY, EVENTUALLY DIGGING ALL THE WAY INTO THE SOUTHEAST AS
RIDGING RETREATS TOWARDS THE FOUR CORNERS REGION. THIS WILL USHER
IN COOLER WEATHER, WITH HIGH TEMPERATURES AS LOW AS THE UPPER 70S
POSSIBLE FOR SOME LOCATIONS ON FRIDAY. ADDITIONAL IMPULSES WILL
KEEP AT LEAST SCATTERED SHOWERS AND STORMS IN THE FORECAST EACH
DAY, WITH RAIN CHANCES GENERALLY PEAKING IN THE AFTERNOON/EVENING.
AVIATION
(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 126 PM EDT MON AUG 17 2026
SCATTERED THUNDERSTORMS WERE ON THE INCREASE EARLY THIS AFTERNOON,
ESPECIALLY OVER FAR EASTERN KY. THE CONCENTRATED AREA OVER FAR
EASTERN KY WILL SHIFT OUT EAST OF THE STATE WITH TIME, BUT THE
INCREASING TREND WILL OTHERWISE CONTINUE THIS AFTERNOON.
LOCALIZED IFR OR WORSE CONDITIONS WILL OCCUR IN THE THUNDERSTORMS,
WITH LARGELY VFR ELSEWHERE. PRECIP IS EXPECTED TO DIE OUT THIS
EVENING, WHICH WOULD LEAVE A POSSIBLE BRIEF RETURN TO VFR FOR MOST
OF THE AREA. HOWEVER, FOG AND LOW CLOUDS ARE FORECAST TO DEVELOP
DURING THE NIGHT AND PERSIST INTO TUESDAY MORNING. THIS WILL
PROBABLY RESULT IN IFR OR WORSE CONDITIONS FOR MOST PLACES.
IMPROVEMENT BACK TO MVFR, AND PERHAPS SOME VFR, IS FORECAST BY THE
END OF THE PERIOD AS FOG DISSIPATES AND CEILINGS RISE DURING THE
DAY ON TUESDAY.
JKL WATCHES/WARNINGS/ADVISORIES
FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR KYZ044-050>052-
058>060-068-069-080-086>088-104-106>120.
SHORT TERM...HAL
LONG TERM...JKL
AVIATION...HAL
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page