766
FXUS63 KJKL 270600 AAA
AFDJKL
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE JACKSON KY
200 AM EDT MON JUL 27 2026
KEY MESSAGES
- WARMER TEMPERATURES AND A GREATER POTENTIAL FOR SHOWERS AND
THUNDERSTORMS START THE NEW WORK WEEK.
- THESE STORMS COULD BE MORE ORGANIZED AND STRONG TO SEVERE LATE
THIS AFTERNOON INTO THE NIGHT DEPENDING ON THUNDERSTORM CLUSTER
DEVELOPMENT AND EVOLUTION TO THE NORTH OF KENTUCKY.
- DRIER WEATHER RETURNS FOR THE SECOND HALF OF THE WEEK.
UPDATE
ISSUED AT 135 AM EDT MON JUL 27 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.
DID USHER THE SHOWERS AND STORMS OUT OF THE FAR SOUTH OVER THE
NEXT COUPLE OF HOURS. THESE MINOR ADJUSTMENTS HAVE BEEN SENT TO
THE NDFD AND WEB SERVERS ALONG WITH A FRESHENING OF THE HWO, SAFS,
AND ZONES.
UPDATE ISSUED AT 725 PM EDT SUN JUL 26 2026
NO MAJOR CHANGES MADE TO THE FORECAST GRIDS AS THE FORECAST
REMAINS ON TRACK THROUGH THE EVENING. HOWEVER, DID INCORPORATE
THE LATEST SURFACE OBS AND MADE A FEW GRIDS EDITS FOR THE 00Z TAF
ISSUANCE. GRIDS HAVE BEEN SAVED AND SENT.
SHORT TERM
(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 311 PM EDT SUN JUL 26 2026
IT HAS BEEN A CHALLENGING CLOUD FORECAST TODAY AS A STRATUS DECK HAS
BEEN SLOW TO ERODE, WITH MOISTURE GETTING STUCK UNDERNEATH A HEALTHY
INVERSION ALOFT. THIS HAS SLOWLY STARTED TO DISSIPATE INTO SOME
LOWER CUMULUS THIS AFTERNOON. GIVEN THIS THE AFTERNOON HIGH
TEMPERATURES HAVE BEEN A BIT MORE DEPRESSED. THESE CLOUDS WILL
CONTINUE TO SCATTER OUT THROUGH THE REMAINDER OF THE AFTERNOON.
THEN WE SEE ONE OF SEVERAL COMPLICATED CONVECTIVE EVOLUTIONS TAKE
PLACE LATER THIS EVENING INTO TONIGHT. THE CAMS ARE GENERALLY
DEVELOPING A COMPLEX OF STORMS ACROSS NORTHERN ILLINOIS AND THIS
WILL DIVE SOUTHWARD UNDER THE INFLUENCE OF THE NORTHWEST FLOW
PATTERN IN PLACE ACROSS THE OHIO VALLEY. THE VAST MAJORITY OF THE
CAMS WANT TO TAKE THIS COMPLEX MAINLY ACROSS PARTS OF WESTERN AND
CENTRAL KENTUCKY. HOWEVER, THERE IS SOME CHANCE THIS CONVECTION
SNEAKS INTO THE LAKE CUMBERLAND AND CUMBERLAND VALLEY REGION
REGION LATER TONIGHT INTO EARLY MONDAY MORNING. GIVEN THIS HAVE
SOME POPS IN THE 20 TO 40 PERCENT RANGE, WITH HIGHEST CHANCES WEST
OF I-75. THE OTHER HAZARD TO CONTEND WITH TONIGHT WILL BE FOG
FORMATION, WITH THE FORECAST SOUNDING ACROSS THE AREA SUGGESTING
MORE OF FOG SCENARIO. THAT SAID, FOR NOW HAVE MOSTLY LIMITED THIS
TO THE RIVER VALLEYS AND PORTIONS OF THE LAKE CUMBERLAND REGION
GIVEN THE POTENTIAL FOR OVERNIGHT CONVECTION.
THIS LEADS INTO WHAT SHOULD BE A MOSTLY DRY DAY FOR MONDAY, BUT SOME
UNCERTAINTY DOES EXIST WITH THIS IDEA. THIS AS LEFT OVER BOUNDARY
AND NORTHWEST FLOW ALOFT COULD LEAD TO SOME KIND OF ISOLATED
CONVECTION. HOWEVER, THIS LOOKS FAIRLY ISOLATED AT THIS POINT GIVEN
THE LACK OF BETTER TRIGGERS FOR CONVECTION AND THE RELATIVELY DRIER
AIRMASS NOTED IN THE PWAT VALUES IN THE 1.2 TO 1.4 RANGE. THIS AS A
WEAK QUAI-STATIONARY BOUNDARY WILL SLIDE INTO THE TENNESSEE VALLEY
AND WEAK HIGH PRESSURE WILL REMAIN NEARBY. THE BIGGER POTENTIAL
DIFFERENCE WILL BE THE MUCH WARMER DAY OF LATE DEPENDING ON THE
CONVECTIVE EVOLUTION, WITH HIGHS CLIMBING INTO THE UPPER 80S TO
LOWER 90S.
MONDAY NIGHT IS LOOKING MORE INTERESTING FOR A MCS LIKE STRUCTURE
POSSIBLY DIVING SOUTHWARD ACROSS PARTS OF KENTUCKY. THERE STILL
REMAINS A FAIR AMOUNT OF UNCERTAINTY ON TIMING AND EVOLUTION OF THIS
COMPLEX OF STORMS. HOWEVER, THERE ARE MANY OF THE CAMS SHOWING A
STORM COMPLEX MOVING OUT OF SOUTHERN MICHIGAN AND DIVING SOUTHWARD
TOWARD THE LOWER OHIO VALLEY. THERE IS ALSO DECENT SIGNALS SHOWING
UP IN THE VARIOUS DETERMINISTIC AND ENSEMBLE SYNOPTIC GUIDANCE, WITH
EVEN SOME OF THE MACHINE LEARNING AND AI GUIDANCE SHOWING SIGNAL FOR
STRONGER STORMS. THERE WILL BE AMPLE MUCAPE IN THE 1000-2000 J/KG
RANGE AND EFFECTIVE SHEAR IN THE 30-40 KNOT RANGE FOR KEEPING THIS
COMPLEX ORGANIZED. EVEN THE DERECHO COMPOSITE PARAMETER REMAINS
ELEVATED, WHICH CAN BE A DECENT SIGNAL FOR MORE ORGANIZED SEVERE
WIND POTENTIAL. THEREFORE, THE PRIMARY RISK WILL BE SEVERE WIND
GUSTS, BUT SOME OF THE ML GUIDANCE WOULD INDICATE A SMALL RISK FOR A
WEAK SPINUP.
LONG TERM
(TUESDAY THROUGH SUNDAY)
ISSUED AT 258 PM EDT SUN JUL 26 2026
THE LONG-TERM PERIOD OPENS TUESDAY MORNING WITH A PRONOUNCED ~596
DAM HIGH OVER THE SOUTHERN ROCKIES WITH A RIDGE AXIS EXTENDING
NORTHWARD INTO CENTRAL CANADA. MEANWHILE, TROUGHING EXTENDS
SOUTHWARD FROM AN AROUND 540 DAM LOW OVER NORTHERN QUEBEC TO ALONG
THE MID-ATLANTIC COAST. AN EMBEDDED SHORTWAVE TROUGH IS PRESENT
OVER THE LOWER GREAT LAKES. THIS WILL BE MIRRORED AT THE SURFACE
BY A 997 MB SURFACE LOW OVER LAKE ERIE. A WARM FRONT EXTENDS
SOUTHWARD FROM THAT LOW TO OVER THE SOUTHERN APPALACHIANS WHILE A
COLD FRONT ARCS SOUTHWEST FROM THE SURFACE LOW OVER SOUTHERN
INDIANA AND ILLINOIS AND THEN BEYOND TO OVER THE HIGH PLAINS OF
MONTANA. THIS WILL LEAVE EASTERN KENTUCKY IN THE LOW'S WARM
SECTOR AT DAYBREAK TUESDAY MORNING WITH A SEASONABLY MOIST AIR
MASS (PWATS AROUND 1.8 INCHES).
THE SURFACE LOW WILL SHIFT EASTWARD ALONG THE PA/NY TWIN TIERS
THROUGH THE DAY AND EVENING ON TUESDAY, DROPPING THE COLD FRONT
ACROSS THE COMMONWEALTH. SUBSTANTIAL UNCERTAINTY REMAINS AS TO
INSTABILITY RECOVERY AHEAD OF THIS BOUNDARY GIVEN THE LIKELIHOOD FOR
CONVECTION EARLY IN THE DAY, AND ESPECIALLY PRIOR TO SUNRISE WITH A
POTENTIAL MCS. IF THE FRONTAL ARRIVAL IS SLOWER AND GREATER
DESTABILIZATION OCCURS, UNSEASONABLY STRONG NORTHWESTERLY FLOW ALOFT
WOULD SUPPORT ROBUST SHEAR AND ORGANIZED CONVECTION. CONVERSELY,
A QUICKER FRONTAL PASSAGE WOULD TEND TO FAVOR KEEPING ANY STRONGER
ORGANIZED CONVECTION CONFINED TO FAR SOUTHEASTERN KENTUCKY OR
PERHAPS ENTIRELY SOUTHEAST OF OUR CWA. IN ADDITION TO THE
CONVECTIVE POTENTIAL, TUESDAY DOES APPEAR BREEZY WITH SOME
MOMENTUM TRANSFER MIXING TO THE SURFACE FROM A LOW-LEVEL JET (30+
KT AT 850 HPA). THE HIGH PWATS COULD ALSO FAVOR SOME ISOLATED
HEAVY RAINFALL. ANY HYDRO PROBLEMS WOULD PROBABLY OCCUR WHERE
SUBSTANTIAL RAINFALL OCCURRED DURING THE LAST 12 HOURS OF THE
SHORT-TERM PERIOD; BY TUESDAY, THE STRONG FLOW ALOFT SHOULD KEEP
CELL MOTIONS QUITE PROGRESSIVE.
ONCE THE FRONT CLEARS THE AREA, COOLER AND DRIER AIR WILL FILTER IN
ON TUESDAY NIGHT AND WEDNESDAY, WITH LREF MEAN PRECIPITABLE WATER
VALUES DROPPING TO BETWEEN 0.75 AND 1.00 INCH, OR NEAR THE 10TH
PERCENTILE RELATIVE TO CLIMATOLOGY. ALOFT, RIDGING WILL REMAIN OVER
THE WEST WHILE TROUGHING LINGERS OVER EASTERN CANADA AND MUCH OF
THE EASTERN CONUS. SURFACE HIGH PRESSURE DRIFTING SOUTH FROM
ONTARIO AND QUEBEC WILL ENSURE DRY CONDITIONS THROUGH FRIDAY.
ANOTHER SHORTWAVE TROUGH DROPS INTO THE BROADER TROUGH DURING THE
UPCOMING WEEKEND. THIS WILL FOSTER ANOTHER SURFACE LOW DEVELOPING
OVER THE PLAINS AND DRIFTING TOWARD THE TENNESSEE VALLEY
VICINITY, BRINGING BACK HIGHER PWATS AND THE RENEWED THREAT OF
CONVECTION FOR SATURDAY AND SUNDAY.
IN SENSIBLE WEATHER TERMS, LOOK FOR A HIGH CHANCE OF SHOWERS AND
THUNDERSTORMS (POPS OF 60 TO 90 PERCENT, HIGHEST IN FAR EASTERN
AND SOUTHEASTERN KENTUCKY) ON TUESDAY. IF SUBSTANTIAL SUNSHINE
MATERIALIZES, SOME OF THE STORMS COULD BE STRONG TO SEVERE AND
ALSO PRODUCE HEAVY DOWNPOURS. IT WILL BE WARM AND HUMID WITH HIGHS
IN THE 80S. FAIR WEATHER FOLLOWS FOR TUESDAY NIGHT THROUGH FRIDAY
WITH HIGHS IN THE LOW TO MID 80S AND LOWS MOSTLY FROM 60 TO 65F.
AS THE THREAT OF SHOWERS AND THUNDERSTORMS RETURNS FOR SATURDAY
AND SUNDAY, DAILY HIGH TEMPERATURES WILL REMAIN AT SIMILAR LEVELS,
BUT NIGHTTIME LOWS WILL MODERATE TO BETWEEN 65 AND 70F WITH
HIGHER HUMIDITY LEVELS.
AVIATION
(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 200 AM EDT MON JUL 27 2026
MAINLY VFR TAFS ARE SET UP ACROSS EASTERN KENTUCKY WITH THE 06Z
ISSUANCE. THIS IS IN THE WAKE OF A THUNDERSTORM CLUSTER EXITING
OUT OF FAR SOUTHWESTERN PARTS OF THE AREA INTO TENNESSEE. EXPECT
VFR TO BE THE CASE THROUGH THE EARLY PART OF THE OVERNIGHT BEFORE
CLEARING SKIES ALLOW FOR AREAS OF PATCHY DENSE FOG TO DEVELOP IN
THE VALLEYS. SOME OF THE FOG COULD SNEAK INTO THE TAF SITES AND
BRING CATEGORIES DOWN INTO MVFR AND IFR - ESPECIALLY FOR THOSE
SOUTHWEST SITES THAT SAW RAIN IN THE LATE EVENING/EARLY OVERNIGHT.
ALL THE FOG WILL CLEAR OUT JUST AFTER SUNRISE ALLOWING VFR
CONDITIONS TO RETURN WITH LIGHT AND VARIABLE WINDS. LATE TONIGHT,
A NEW CLUSTER OF THUNDERSTORMS MAY START TO IMPINGE ON THE
NORTHERN TERMINALS TOWARDS MIDNIGHT. HAVE INCLUDED A PROB30 AT
BOTH IOB AND SYM FOR THIS.
JKL WATCHES/WARNINGS/ADVISORIES
NONE.
UPDATE...GREIF
SHORT TERM...DJ
LONG TERM...GEERTSON
AVIATION...VORST/GREIF
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