459
FXUS63 KLMK 211755
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
155 PM EDT THU MAY 21 2026
..UPDATED AVIATION DISCUSSION
KEY MESSAGES
* COLD FRONTAL BOUNDARY WILL STALL OUT SOUTH OF THE REGION TODAY
WITH MOST AREAS STAYING DRY, EXCEPT ALONG THE KY/TN BORDER WHERE A
FEW SHOWERS WILL BE POSSIBLE.
* STALLED OUT FRONT WILL LIFT NORTHWARD AS A WARM FRONT ON FRIDAY
WITH WIDESPREAD SHOWERS IN THE MORNING. AS KENTUCKY GETS INTO THE
WARM SECTOR, THUNDERSTORMS WILL BE POSSIBLE FRIDAY AFTERNOON
AND EVENING WITH A RISK OF STORMS BECOMING STRONG/SEVERE.
* BUSY WEATHER PATTERN RETURNS WITH A 30-50% CHANCE FOR CENTRAL KY
TO RECEIVE MORE THAN AN INCH OF RAIN ON FRIDAY. ADDITIONAL ROUNDS
OF RAIN ARE EXPECTED THROUGH THE REST OF THE WEEKEND AND INTO NEXT
WEEK.
SHORT TERM /THROUGH FRIDAY NIGHT/
ISSUED AT 329 AM EDT THU MAY 21 2026
SURFACE ANALYSIS SHOWS A COLD FRONTAL BOUNDARY PUSHING SOUTHWARD
INTO NORTHERN TENNESSEE THIS MORNING. IN THE POST FRONTAL AIRMASS,
LIGHT NORTHEAST WINDS WERE SEEN ACROSS THE REGION. AREA RADARS SHOW
A CONTINUATION OF SHOWER ACROSS THE SOUTHEASTERN HALF OF THE
FORECAST AREA. A REMNANT MCV CONTINUES TO TRACK NORTHEASTWARD
ACROSS SOUTH-CENTRAL KY. THIS FEATURE SHOULD CONTINUE TO MOVE OFF
TO THE NORTHEAST INTO THE BLUEGRASS REGION THIS MORNING. LIGHT RAIN
SHOWERS ARE EXPECTED TO CONTINUE IN AREAS ALONG/SOUTH OF THE
PARKWAYS THROUGH SUNRISE. CURRENT TEMPERATURES RANGED FROM THE
LOWER 60S OVER SOUTHERN INDIANA AND NORTHERN KENTUCKY TO THE MID-
UPPER 60S DOWN ALONG THE KY/TN BORDER.
FOR TODAY, LOW CLOUDS ARE EXPECTED TO HOLD SWAY ACROSS THE REGION
FOR MUCH OF THE DAY WITH MORNING SHOWERS EXPECTED TO REMAIN ONGOING
IN AREAS ALONG AND SOUTH OF THE WK/BG PARKWAYS. AN AREA OF HIGH
PRESSURE OVER THE GREAT LAKES WILL ATTEMPT TO PUSH SOME DRIER AIR
INTO SOUTHERN INDIANA AND NORTHERN KENTUCKY THIS AFTERNOON WHICH MAY
LEAD TO SOME BREAKS IN THE CLOUD COVER. TEMPERATURES TODAY WILL BE
WELL BELOW NORMAL AND WILL BE CHALLENGING TO FORECAST. BLENDED
GUIDANCE IS LIKELY WAY TOO HIGH TODAY WITH READINGS IN THE UPPER
60S/LOWER 70S. HOWEVER, IF CLOUD COVER REMAINS THICK AND ENTRENCHED
ACROSS THE REGION, HIGHS MAY STRUGGLE TO REACH 60 ACROSS SOUTHERN
INDIANA AND THE NORTHERN HALF OF KENTUCKY, WITH LOWER-MID 60S ACROSS
SOUTHERN KENTUCKY.
FOR TONIGHT, CONDITIONS LOOK TO REMAIN FAIRLY DRY ACROSS THE REGION
THIS EVENING, THOUGH WE CAN'T RULE OUT SOME STRAY SHOWERS DOWN
ACROSS SOUTHERN KENTUCKY. LATER TONIGHT, THE AFOREMENTIONED COLD
FRONT WILL START TO LIFT NORTHWARD AS A WARM FRONT. COMBINATION OF
INCREASING ISENTROPIC LIFT AND WARM ADVECTION WITH THE FRONT WILL
LEAD TO A GRADUAL UPTICK IN SHOWER ACTIVITY TOWARD DAWN FRIDAY.
OVERNIGHT LOWS WILL RANGE FROM THE UPPER 50S OVER SOUTHERN INDIANA
AND THE NORTHERN HALF OF KENTUCKY TO THE LOWER 60S OVER SOUTHERN
KENTUCKY.
FRIDAY LOOKS A BIT MORE INTERESTING AS THE AFOREMENTIONED WARM FRONT
SURGES NORTHWARD ACROSS THE REGION PLACING MUCH OF OUR AREA WITHIN
THE WARM SECTOR. LATEST GUIDANCE SHOWS A MID-LEVEL WAVE APPROACHING
FROM THE SOUTHWEST WITH HEIGHT FALLS SPREADING ACROSS THE REGION.
MID-LEVEL FLOW WILL GRADUALLY INCREASE THROUGH THE DAY. MODEL
SOUNDINGS SHOW INCREASING INSTABILITY WITHIN THE WARM SECTOR FRIDAY
AFTERNOON AS SHEAR PROFILES BECOME MORE FAVORABLE FOR ORGANIZED
CONVECTION. OVERALL, INSTABILITY MAY BE RATHER MARGINAL ACROSS THE
REGION GIVEN EXPECTED CLOUD COVER AND ONGOING PRECIPITATION.
HOWEVER, SOME GUIDANCE IS SHOWING A BIT MORE INSTABILITY DEVELOPING
WITH CLUSTERS OF STRONG STORMS MOVING ACROSS THE REGION. SPC HAS
THE AREA IN A MARGINAL RISK AND WE AGREE HERE BASED ON THE SIGNALS.
SHOULD WE GET A BIT STRONGER HEATING AND MORE INSTABILITY, A HIGHER
RISK OF STRONG/SEVERE STORMS IS POSSIBLE. GIVEN THE SHEAR PROFILES,
A MIX OF MULTI-CELLUAR CLUSTERS AND SOME SUPERCELLS WOULD BE
POSSIBLE WHICH COULD PROMOTE A DAMAGING WIND AND ISOLATED TORNADO
RISK FRIDAY AFTERNOON AND EVENING. HIGHS FRIDAY LOOK TO WARM INTO
THE MID-UPPER 70S WITH OVERNIGHT LOWS IN THE 60S.
LONG TERM /SATURDAY THROUGH WEDNESDAY/
ISSUED AT 329 AM EDT THU MAY 21 2026
THE STRETCH OF UNSETTLED WEATHER CONTINUES INTO THE WEEKEND AS AN
AREA OF SURFACE LOW PRESSURE LIFTS NORTHEAST THROUGH THE OHIO VALLEY
EARLY SATURDAY. AS IT DOES SO, SOME OF THE DEEPEST MOISTURE
ASSOCIATED WITH THE SYSTEM ALSO DEPARTS TO THE NORTHEAST, DECREASING
OUR PW DOWN TO THE 1.25-1.50" RANGE (JUST UNDER 80TH PERCENTILE
CLIMATOLOGICALLY). WHILE CHANCES FOR SHOWERS AND THUNDERSTORMS WILL
CONTINUE, THEY WILL SLOWLY DECREASE THROUGHOUT THE DAY FROM WEST TO
EAST. WITH THE EXITING LOW AND DECREASING PW, RAINFALL TOTALS ARE
FORECAST TO BE MUCH LIGHTER FOR SATURDAY (0.1 TO 0.2").
AS A CUTOFF UPPER LOW BEGINS TO DEVELOP OVER TEXAS LATE SATURDAY AND
SHORTWAVES FROM IT BEGIN TO MOVE NORTHWARD, A BRIEF PERIOD OF MOSTLY
DRY CONDITIONS IS POSSIBLE (10-20% CHANCE OF RAIN) SATURDAY NIGHT
INTO EARLY SUNDAY. ONCE THE ENERGY FROM THE CUTOFF LOW REACHES OUR
REGION ON SUNDAY, ANOTHER ROUND OF SHOWERS AND SCATTERED
THUNDERSTORMS IS POSSIBLE (50-70% CHANCE FORECAST).
THE CUTOFF UPPER LOW THROUGH THE REMAINDER OF THE FORECAST PERIOD
WILL BE NEARLY STATIONARY, SLOWLY DRIFTING NORTHWARD TOWARDS THE
CENTRAL PLAINS THROUGH WEDNESDAY. IN TURN, SOUTHERLY FLOW ON THE
EASTERN SIDE OF THE LOW WILL ALLOW FOR AMPLE MOISTURE TO MOVE OVER
THE REGION. LREF PW VALUES RANGE FROM 1.55-1.75" (>90TH PERCENTILE
CLIMATOLOGICALLY) FROM SUNDAY MORNING THROUGH WEDNESDAY AFTERNOON,
PROVIDING MORE THAN ENOUGH MOISTURE FOR SHOWERS AND STORMS TO
DEVELOP. WITH SEVERAL SHORTWAVES EXPECTED TO MOVE OVER THE AREA, AS
WELL AS A FRONTAL BOUNDARY STALLING JUST TO OUR NORTH AFTER TUESDAY,
ADDITIONAL CHANCES FOR SHOWERS AND STORMS APPEARS LIKELY WELL INTO
NEXT WEEK.
AVIATION /18Z TAFS THROUGH 00Z SATURDAY/
ISSUED AT 154 PM EDT THU MAY 21 2026
IFR-LOW END MVFR CONDITIONS WILL CONTINUE INTO THE EVENING AND
OVERNIGHT HOURS. LIGHT TO MODERATE RAIN SHOWERS IN THE EAST WILL END
OVER THE NEXT FEW HOURS THOUGH CEILINGS WILL STRUGGLE TO IMPROVE
ACROSS THE AREA. OCCASIONAL HIGH-END MVFR TO LOW-END VFR CONDITIONS
COULD RETURN TO HNB-SDF OVERNIGHT BEFORE THEY LOWER AGAIN AFTER
SUNRISE. OTHERWISE, LIGHT NE WINDS WILL PERSIST INTO TOMORROW
MORNING, WITH CEILINGS REMAINING LOW BETWEEN IFR-MVFR CONDITIONS
THROUGH FRIDAY. IN THE MORNING, WINDS BEGIN TO SHIFT OUT OF THE E TO
SE WITH A WIDE SWATH OF LIGHT TO MODERATE RAIN FOR ALL AIRPORTS
MOVING IN FROM THE SOUTHWEST. IF CEILINGS IMPROVE IN THE MORNING,
THEY WILL LOWER ONCE AGAIN WITH THE WIDESPREAD INCOMING RAIN ON
FRIDAY, WHICH WILL BECOME MORE SCATTERED AND MIXED WITH STORMS IN
THE AFTERNOON. LEX/RGA MAY DIP INTO LIFR CONDITIONS WITH THE CURRENT
CEILING FORECAST IN THE MORNING INTO THE AFTERNOON AS WELL.
OTHERWISE, MVFR TO IFR CONDITIONS ARE EXPECTED FOR EVERYONE FRIDAY
AFTERNOON.
LMK WATCHES/WARNINGS/ADVISORIES
KY...NONE.
IN...NONE.
SHORT TERM...MJ
LONG TERM...BEN
AVIATION...BKF
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