191
FXUS63 KJKL 051755
AFDJKL
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
155 PM EDT SUN JUL 5 2026
KEY MESSAGES
- SCATTERED TO NUMEROUS SHOWERS AND STORMS RETURN SUNDAY AND
MONDAY AS A SLOW-MOVING COLD FRONT ARRIVES. A FEW STORMS COULD
PRODUCE ISOLATED STRONG WINDS AND LOCALIZED FLASH FLOODING.
- THE HEAT WAVE BREAKS NEXT WEEK, WITH DAILY HIGHS RETURNING TO
NEAR-NORMAL LEVELS IN THE MID TO UPPER 80S ALONGSIDE DAILY
CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS.
UPDATE
ISSUED AT 1210 AM EDT SUN JUL 5 2026
NO BIG CHANGES NEEDED FOR THIS UPDATE. HOWEVER, DID MAKE SOME
MINOR POP ADJUSTMENTS TO ACCOUNT FOR RADAR TRENDS, WITH CONVECTION
DEVELOPING ALONG THE HIGHER TERRAIN NEAR THE VIRGINIA BORDER. THE
LATEST CAMS HAVE BEEN VARYING IN WHERE CONVECTION DEVELOPS AND
NONE OF THEM ARE REALLY DOING WELL WITH THE INITIATION THIS LATE
MORNING HOUR. GIVEN THE LACK OF BETTER FORCING MOST CONVECTION
WILL DEVELOP ON HIGHER TERRAIN OR OUTFLOWS THROUGH THE AFTERNOON
AND EVENING.
UPDATE ISSUED AT 730 AM EDT SUN JUL 5 2026
NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST WITH MAINLY JUST
THE INCLUSION OF THE LATEST OBS AND TRENDS FOR THE T/TD/SKY GRIDS.
THESE MINOR ADJUSTMENTS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS
ALONG WITH A FRESHENING OF THE ZONES.
SHORT TERM
(TODAY THROUGH MONDAY)
ISSUED AT 435 AM EDT SUN JUL 5 2026
08Z SFC ANALYSIS SHOWS A NOW MUCH WEAKENED AREA OF HIGH PRESSURE
OVER THE TENNESSEE VALLEY THAT IS EXTENDING ITS LIMITED INFLUENCE
INTO EASTERN KENTUCKY. AS SUCH, THE EVENING CONVECTION HAS COME TO
AN END AND SKIES HAVE MOSTLY CLEARED WHILE THE WINDS ARE LIGHT.
THIS IS LEADING TO RADIATIONAL COOLING, A SMALL RIDGE TO VALLEY
TEMPERATURE DIFFERENCE, AND THE DEVELOPMENT OF PATCHY DENSE VALLEY
FOG. CURRENTLY, TEMPERATURES ARE GENERALLY IN THE LOWER 70S WHILE
DEWPOINTS ARE IN THE UPPER 60S TO LOW 70S ACROSS THE AREA.
THE MODELS, AND THEIR INDIVIDUAL ENSEMBLE SUITES, REMAIN IN
EXCELLENT AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE
FORECAST. THEY ALL SHOW THAT THE 5H RIDGE THAT BROUGHT THE HEAT
OF THE PAST WEEK HAS SHRUNK SOUTH IN THE FACE OF TOUGHING MOVING
INTO THE OHIO VALLEY. THIS AREA OF LOWER HEIGHTS TO THE NORTH IS
ALSO CARRYING WITH IT MORE IN THE WAY OF ENERGY - WORKING INTO
KENTUCKY THIS MORNING. ADDITIONAL HEIGHT FALLS GRADUALLY SPREAD
INTO THIS PART OF THE STATE THROUGH TONIGHT THOUGH THE BULK OF THE
MID LEVEL PERTURBANCES STAY WELL OFF TO THE WEST OF THE JKL CWA.
THIS PATTERN CONTINUES THROUGH THE DAY, MONDAY, WITH BETTER
FORCING ALOFT REMAINING TO OUR WEST AND GENERAL LOWER HEIGHTS AT
MID LEVELS BUT NOTHING WITH A STRONG PUSH OR CONCENTRATION SEEN IN
THE MODELS. THIS WILL MEAN THAT THE MESO-SCALE AND DIURNAL
DYNAMICS WILL DOMINATE THE WEATHER FLOW FOR EASTERN KENTUCKY
THROUGH THE START OF THE POST HOLIDAY WORK WEEK. GIVEN THE STILL
PRETTY GOOD AGREEMENT AMONG THE MODELS, THE NBM WAS USED AS THE
STARTING POINT FOR THE GRIDS WITH SOME ADJUSTMENT APPLIED FOR
MINOR TERRAIN DETAILS IN THE TEMPERATURE GRIDS TONIGHT ALONG WITH
ADDITIONAL CONVECTIVE TIMING AND PLACEMENT DETAILS PROVIDED BY THE
LATEST CAMS GUIDANCE - BUT WITH SMOOTHING APPLIED TO BLUNT THE
NOISINESS OF THE CONSENSUS MODEL DATA.
SENSIBLE WEATHER FEATURES A STILL WARM AND HUMID DAY FOR THE
AREA, BUT TEMPERATURES AND HEAT INDICES WILL NOT BE QUITE AS HIGH
AS THE PAST FEW DAYS. AGAIN, SOME SHOWERS AND STORMS WILL LIKELY
BE AROUND TO PROVIDE ADDITIONAL RELIEF. ANY OF THE STORMS IN THE
AFTERNOON AND MUCH OF THE EVENING WILL HAVE THE POTENTIAL TO BE
INTENSE WITH STRONG TO DAMAGING WIND GUSTS AND HEAVY RAIN THE
PRIMARY CONCERNS. DUE TO SLOW STORM MOTION AND POTENTIAL FOR
TRAINING CELLS THERE WILL ALSO BE A RISK FOR LOCALIZED FLOODING
FROM THE STORMS LATER TODAY. THEN, LOOK FOR ANOTHER DIURNALLY
QUIET NIGHT WITH SCANT (BUT NOT ZERO) CHANCES FOR SHOWERS OR
STORMS ALONG WITH VALLEY FOG AND A MINIMAL RIDGE TO VALLEY
TEMPERATURE DIFFERENCE - THANKS TO STILL QUITE ELEVATED
DEWPOINTS. FOR MONDAY, ANOTHER SEASONABLY WARM DAY WILL UNFOLD
WITH MAINLY DIURNALLY DRIVEN CONVECTION POPPING UP BY AFTERNOON
AND LINGERING INTO THE EVENING.
THE MAIN ADJUSTMENTS TO THE NBM STARTING POINT WERE TO TWEAK THE
NBM TEMPS A SMIDGE FOR VERY MINOR TERRAIN DISTINCTIONS TONIGHT
AND TO ADD MORE HIGH RESOLUTION CAMS (THOUGH SMOOTHED) DETAILS
INTO THE POPS AND THUNDER POTENTIAL GRIDS THROUGH MONDAY EVENING.
LONG TERM
(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 AM EDT SUN JUL 5 2026
THE MAIN CHANGE TO GRIDS FOR THE FIRST PART OF THE EXTENDED
FORECAST THIS MORNING WAS TO ADD IN SOME SLIGHT TERRAIN DETAILS
EACH NIGHT ON ACCOUNT OF THE DIURNALLY CLEARING SKIES THAT ARE
EXPECTED EACH NIGHT THROUGH WEDNESDAY MORNING. DID ALSO INCLUDE
SOME RIVER VALLEY FOG TOWARD DAWN IN THE EARLY MORNING GRIDS.
GENERAL TROUGHING ALOFT STILL LOOKS TO KEEP THINGS UNSETTLED
THROUGH AT LEAST THE MIDDLE OF THE WORK WEEK WITH SEASONABLY WARM
TEMPERATURES AND DEWPOINTS STILL ON THE WET SIDE OF CLIMATOLOGY.
THE PREVIOUS LONG TERM DISCUSSION FOLLOWS:
THE LONG-TERM PERIOD OPENS MONDAY WITH THE PRIOR WEEK'S HEAT WAVE
JUST A MEMORY. THE 04/12Z MODEL SUITE ANALYSIS BEGINNING AT 12Z
MONDAY SHOWS A SPLIT FLOW PATTERN OVER THE EASTERN GREAT LAKES WITH
A POSITIVELY-TILTED TROUGH EXTENDING SOUTHWESTWARD INTO THE MID
AND LOWER MISSISSIPPI VALLEY WHILE A RIDGE AXIS EXTENDS NORTHWARD
TO OVER NORTHERN GREENLAND. MEANWHILE, AN ~593 DAM HIGH WILL
RESIDE OVER THE UPPER RIO GRANDE VALLEY BENEATH A TROUGH OVER
CENTRAL CANADA. AT THE LOWER LEVELS, THE PATTERN IS SUBTLE. A WEAK
AREA OF LOW PRESSURE IS LIKELY TO BE IN THE VICINITY OF SOUTHERN
INDIANA WITH A COLD FRONT EXTENDING SOUTHWEST INTO THE OZARKS.
WORKING THROUGH THE UPCOMING WORK WEEK, GUIDANCE IS IN FAIR AGREEMENT
SHOWING THE UPPER-LEVEL TROUGH PROPAGATING EASTWARD WITH ITS AXIS
CROSSING THE CWA ON TUESDAY, CAUSING THE AFOREMENTIONED COLD
FRONT TO DROP THROUGH THE FORECAST AREA. THE NOTABLE EXCEPTION IS
THE ECMWF DETERMINISTIC HOLDING BACK A WEAK CLOSED LOW OVER THE
MID-MISSISSIPPI VALLEY WHICH WOULD INHIBIT THE COLD FRONT'S
SOUTHWARD PROGRESSION. DIURNALLY MODULATED DEEP CONVECTION IS
PROBABLE ON BOTH MONDAY INTO TUESDAY WITH THE FRONTAL BOUNDARY
NEARING AND DIPPING INTO THE AREA. GREATER UNCERTAINTY ON OVERALL
CONVECTIVE COVERAGE COMES ON WEDNESDAY AND DEPENDS ON WHETHER THE
FRONT EFFECTIVELY DIPS SOUTH OF THE COMMONWEALTH OR GETS HUNG UP.
IN EITHER CASE, THE RAIN CHANCES APPEAR TO INCREASE AGAIN HEADING
LATER IN THE WEEK AS THE TROUGH OVER CANADA BEGINS TO DIG
SOUTHEASTWARD AND THE SOUTHWEST US HIGH SHIFTS WESTWARD AND THEN
BEGINS TO AMPLIFY, PUMPING UP A ROBUST, POSITIVELY TILTED RIDGE
AXIS FROM THE DESERT SOUTHWEST TO SOUTHERN NUNAVUT. AT THE
SURFACE, THE FRONT OVER US OR TO OUR SOUTH TURNS FRONTOLYTIC AS A
NEW COLD FRONT SETTLES SOUTHWARD TOWARD THE OHIO VALLEY.
IN TERMS OF HEAVY RAINFALL, A MARGINAL (LEVEL 1 OF 4) ERO IS IN PLACE
THROUGH MONDAY NIGHT TO HIGHLIGHT THE THREAT OF ISOLATED FLASH
FLOODING SHOULD STORMS BECOME PERSISTENT OVER A GIVEN LOCATION AHEAD
OF THE FIRST COLD FRONT. A RENEWED LOW-END EXCESSIVE RAINFALL THREAT
MAY RETURN LATE IN THE WEEK AS MOISTURE RETURNS AHEAD OF THE
SECOND BOUNDARY, BUT THAT IS BEYOND THE WPC ERO WINDOW AT THIS
POINT. TEMPERATURES THROUGH THE PERIOD WILL SETTLE BACK INTO THE
MID TO UPPER 80S FOR DAILY HIGHS EACH AFTERNOON WHILE NIGHTTIME
LOWS RETREAT INTO THE 65 TO 70F RANGE FOR MOST LOCALES. THE
TYPICAL VALLEY FOG IS LIKELY ON ANY NIGHT WITH SUBSTANTIAL
CLEARING.
AVIATION
(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 155 PM EDT SUN JUL 5 2026
WE ARE SEEING SOME SCATTERED CUMULUS DEVELOP THIS AFTERNOON AND
THESE WILL REMAIN AROUND THE 3.5 KFT LEVEL IN MOST CASES. WE ARE
SEEING SOME DEEPER CONVECTION DEVELOP ALONG THE HIGHER TERRAIN,
BUT SO FAR HAS BEEN MORE LIMITED THAN EXPECTED SO FAR. GIVEN THIS
OPTED TO PUSH BACK THE START TIME OF THE PROB30 FOR THUNDERSTORMS
ANOTHER HOUR, BUT GIVEN THE LACK OF CONVECTION SO FAR THIS
AFTERNOON OPTED TO NOT GO TEMPO. OUTSIDE CONVECTION WINDS WILL
REMAIN LIGHT AND VARIABLE GENERALLY BELOW 5 KNOTS.
JKL WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...DJ
SHORT TERM...GREIF
LONG TERM...GEERTSON/GREIF
AVIATION...DJ
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page