429  
FXUS63 KLMK 111726  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
126 PM EDT TUE AUG 11 2026  
   
..UPDATED AVIATION DISCUSSION
 
 
   
KEY MESSAGES
 
 
* THERE IS A LEVEL 3 OF 5 (ENHANCED) RISK FOR SEVERE WEATHER THIS  
EVENING NORTH OF A ROUGHLY BEDFORD, INDIANA TO RICHMOND, KENTUCKY  
LINE, WITH THE RISK DECREASING FURTHER SOUTHWEST. DAMAGING WINDS,  
SOME SIGNIFICANT (> 75 MPH), ARE THE PRIMARY HAZARD.  
 
* REPEATED ROUNDS OF HEAVY RAINFALL IN THUNDERSTORMS TONIGHT AND  
AGAIN TOMORROW COULD RESULT IN LOCALIZED FLASH FLOODING. THERE IS  
A LEVEL 2 OF 4 (SLIGHT) RISK FOR EXCESSIVE RAINFALL.  
 
* ADDITIONAL ROUNDS OF STORMS ARE POSSIBLE (40-60% CHANCE) THROUGH  
FRIDAY. THERE IS A LEVEL 2 OF 5 (SLIGHT) RISK FOR SEVERE WEATHER  
TOMORROW WEST OF I-65, WITH DAMAGING WINDS THE PRIMARY CONCERN.  
 
* OUTSIDE OF STORMS, HEAT INDICES ARE LIKELY (50-80% CHANCE) TO  
SURPASS 100 DEGREES WEST OF I-65 EACH AFTERNOON THROUGH THURSDAY,  
AND AREA-WIDE OVER THE WEEKEND.  
 

 
   
UPDATE
 
 
ISSUED AT 923 AM EDT TUE AUG 11 2026  
 
SEVERE THUNDERSTORM WATCH #564 WILL BE IN EFFECT UNTIL 2 PM EDT THIS  
AFTERNOON ACROSS OUR FAR NE CWA (HARRISON, SCOTT, BOURBON, AND  
NICHOLAS COUNTIES). KEEPING A CLOSE EYE ON THE UPSTREAM BOWING  
SEGMENT THAT HAS LATCHED ONTO THE IMPRESSIVE ML CAPE GRADIENT  
STRETCHING ACROSS SW OHIO INTO NE KENTUCKY. CURRENTLY, THERE IS  
ENOUGH 0-6 KM DEEP LAYER SHEAR TO SUSTAIN SOME COLD POOL/UPDRAFT  
BALANCE, HOWEVER THE FARTHER SE THE COMPLEX TRACKS, IT WILL START TO  
OUTRUN THE BEST 0-6 KM SHEAR AND WILL LIKELY WEAKEN INTO NE KY.  
11/13Z MESOANALYSIS SHOWS LESS THAN 25 KNOTS OF 0-6 KM SHEAR SOUTH  
OF THE OHIO RIVER, AND WE ARE ALREADY SEEING SOME OF THE OUTFLOW  
OUTRUN THE REFLECTIVITY OVER SW OHIO. SO, OVERALL NOT TOO CONCERNED  
FOR OUR FAR NE COUNTIES, BUT CAN'T RULE OUT A SEVERE WIND THREAT AS  
THE COMPLEX WEAKENS INTO OUR AREA LATE MORNING TO AROUND MIDDAY.  
 

 
   
SHORT TERM /THROUGH TONIGHT/
 
 
ISSUED AT 316 AM EDT TUE AUG 11 2026  
 
***** SEVERE WEATHER RISK THIS EVENING *****  
 
EARLY TUESDAY MORNING, UPPER LEVEL RIDGING WAS MAINTAINING  
SEASONABLY WARM AND HUMID CONDITIONS ACROSS NORTHERN KENTUCKY AND  
SOUTHWEST INDIANA, WITH TEMPERATURES/DEWPOINTS MAINLY IN THE  
UPPER/MID 70S AT 3AM. MEANWHILE, A WEAK MID LEVEL DISTURBANCE  
ON THE NORTHEAST PERIPHERY OF THE RIDGE TRIGGERED STORMS OVER  
PORTIONS OF OHIO INTO WEST VIRGINIA. NORTHWEST FLOW ALOFT  
SHOULD CONTINUE TO CARRY THESE SOUTHEASTWARD ACROSS WEST  
VIRGINIA - KEEPING THEM OUT OF OUR LOCAL AREA; HOWEVER, THE HRRR  
AND NAMNEST - THE TWO MODELS BEST HANDLING THE PLACEMENT OF  
CURRENT CONVECTION - SUGGEST REDEVELOPMENT UPSTREAM OVER  
NORTHERN/CENTRAL INDIANA TOWARD DAYBREAK, AND THIS SECOND WAVE  
COULD AFFECT OUR LOCAL AREA DURING THE MORNING INTO EARLY  
AFTERNOON. CONVECTIVE ALLOWING MODELS (CAMS) DISAGREE ON  
PRECISELY HOW MUCH OF OUR AREA SEES EARLY DAY ACTIVITY WITH THIS  
WAVE, WITH THE HRRR AND ARW MERELY GRAZING OUR NORTHEAST  
COUNTIES, THE RRFS HITTING AREAS NORTHEAST OF A ROUGHLY  
LOUISVILLE TO RICHMOND LINE, AND THE NAMNEST BRINGING A DECAYING  
LINE SOUTH ACROSS VIRTUALLY THE ENTIRE CWA. GIVEN THE MEAN WIND  
IS GENERALLY OUT OF THE WEST- NORTHWEST (AROUND 280-290  
DEGREES), AND HAVING SEEN THE NAMNEST OVERDO AN MCS'S RIGHT TURN  
INTO HIGHER THETA-E AIR SEVERAL TIMES IN THE PAST, OUR FORECAST  
LEANS TOWARDS THE HRRR/ARW SOLUTION, WITH JUST A LOW (20-30%)  
CHANCE OF A STORM EAST OF MADISON, IN TO LEXINGTON, KY LINE MID  
MORNING-EARLY AFTERNOON.  
 
THE EVOLUTION OF THIS MORNING ACTIVITY WILL BE CRITICAL IN DICTATING  
THE TRAJECTORY OF THE NEXT AND POTENTIALLY MORE IMPACTFUL WAVE OF  
STORMS THIS EVENING INTO TONIGHT. THE LARGE-SCALE SET-UP: A  
SHORTWAVE TROUGH EMBEDDED WITHIN BROAD WEST-NORTHWEST FLOW WILL  
PROVIDE LIFT TO TRIGGER STORM DEVELOPMENT ACROSS IOWA/SOUTHERN  
MINNESOTA/SOUTHERN WISCONSIN THIS MORNING, WITH THAT ACTIVITY  
GENERALLY FAVORED TO SPREAD SOUTHEAST ALONG THE INSTABILITY AXIS  
DURING THE AFTERNOON AND EVENING. IF EARLY DAY ACTIVITY STAYS TO OUR  
NORTHEAST, THE EFFECTIVE BOUNDARY (AND HENCE INSTABILITY GRADIENT)  
SHOULD KEEP THE FOCUS FOR EVENING STORMS ACROSS CENTRAL/NORTHERN  
INDIANA AND MUCH OF OHIO; HOWEVER, IF WE HAVE MORE IN THE WAY OF  
EARLY DAY STORMS, EVENING STORMS COULD TAKE A RIGHT TURN AND DIVE  
SOUTH ALONG THE REMNANT OUTFLOW BOUNDARY. IN EITHER CASE, SOME  
GUIDANCE - MOST NOTABLY THE MOST RECENT (04Z) HRRR ITERATION -  
SUGGESTS THESE AFTERNOON AND EVENING STORMS WILL DEVELOP A STRONG  
COLD POOL, AND PRODUCE WIDESPREAD DAMAGING WINDS (WITH SOME  
LOCATIONS SEEING GUSTS > 75 MPH) WHEREVER THEY TRACK. BASED ON THE  
BEST OVERLAP OF SHEAR AND INSTABILITY, THE MOST FAVORED CORRIDOR  
WOULD BE JUST NORTHEAST OF OUR LOCAL AREA, BUT GIVEN THE UNCERTAINTY  
AND POTENTIAL FOR SIGNIFICANT IMPACTS THE SPC HAS AREAS NORTH OF A  
ROUGHLY BEDFORD, INDIANA TO RICHMOND, KENTUCKY LINE OUTLOOKED IN A  
LEVEL 3 OF 5 (ENHANCED) RISK FOR SEVERE WEATHER; THE SLIGHT RISK  
EXTENDS SOUTHWARD TO A ROUGHLY HUNTINGBURG, INDIANA TO WINDSOR,  
KENTUCKY LINE. WIND IS IN CIG 1 HATCHING, INDICATING POTENTIAL FOR  
75+ MPH GUSTS CAPABLE OF STRUCTURAL (PRIMARILY SHINGLE/SIDING) AND  
SIGNIFICANT TREE (LARGE TREES SNAPPED, MANY LIMBS DOWNED) DAMAGE,  
WITH THE LATTER LIKELY TO ALSO RESULT IN NUMEROUS POWER OUTAGES  
(FROM TREES/LIMBS FALLING ON LINES). IN ADDITION, THERE IS A 2%  
TORNADO RISK, SUGGESTING A LOW BUT NONZERO CHANCE OF A BRIEF SPIN UP  
IN THE LINE OF STORMS, MAINLY IN THE NORTHERN PORTION OF ANY BOWING  
SEGMENTS WHERE THE LINE BECOMES NEARLY ORTHOGONAL TO 0-3KM SHEAR  
VECTORS (ROUGHLY OUT OF 280 DEGREES). HOWEVER, WE'D LIKE TO  
REITERATE THAT CONFIDENCE ON STORM TRACK IS LOW; THERE IS POTENTIAL  
THAT MOST/ALL OF THIS PASSES TO OUR NORTH, LEAVING US UNSCATHED.  
 
OUTSIDE OF STORMS, IT'LL BE A SEASONABLY HOT AND MUGGY DAY WITH THE  
HREF/REFS SUGGESTING A MEDIUM-HIGH PROBABILITY (50-80% CHANCE) OF  
AFTERNOON HEAT INDICES IN THE TRIPLE DIGITS WEST OF I-65. THE  
GREATEST POTENTIAL FOR HEAT INDICES TOPPING 105 SHOULD BE CONFINED  
TO AREAS WEST OF A ROUGHLY BEDFORD, IN TO SCOTTSVILLE, KY LINE,  
WHERE A HEAT ADVISORY IS IN EFFECT.  
 
***** FLOODING POTENTIAL TONIGHT INTO WEDNESDAY MORNING *****  
 
ONCE THE FORWARD-PROPAGATING PORTION OF THE LINE PUSHES THROUGH (OR  
TO THE NORTHEAST OF) THE LOCAL AREA, A LINGERING OUTFLOW BOUNDARY  
COULD SERVE AS A FOCUS FOR ADDITIONAL STORMS ON THE NOSE OF WHAT THE  
RAP/NAM DEPICT AS A 30-35 KT WESTERLY LLJ. WHILE UPSHEAR CORFIDI  
VECTORS ARE 20-30 KT (TOWARDS THE SOUTHEAST), WHICH BY ITSELF WOULD  
SUGGEST ENOUGH STORM MOTION TO KEEP THE HYDRO RISK LOW, TRAINING  
CELLS COULD LEAD TO REPEATED ROUNDS OF HEAVY RAINFALL OVER THE SAME  
AREAS IF THE BOUNDARY LAYS OUT IN A NORTH-SOUTH ORIENTATION. AS WITH  
THE EVENING MCS, UNCERTAINTY IS HIGH IN WHERE (AND EVEN WHETHER)  
THIS WILL SET UP, BUT CONCERN IS GREATEST IN AREAS EAST OF A ROUGHLY  
MADISON, INDIANA TO LEXINGTON, KENTUCKY LINE WHERE WPC HAS A LEVEL 3  
OF 4 (MODERATE) RISK FOR EXCESSIVE RAINFALL, AND WHERE THE HREF AND  
REFS ENSEMBLE MAX DEPICT SWATHS OF 6+ INCHES OF RAINFALL IN JUST A  
FEW HOURS TONIGHT INTO WEDNESDAY MORNING.  
 

 
   
LONG TERM /WEDNESDAY THROUGH MONDAY/
 
 
ISSUED AT 316 AM EDT TUE AUG 11 2026  
 
***** ADDITIONAL STORMS WEDNESDAY INTO WEDNESDAY NIGHT *****  
 
DEPENDING ON HOW THINGS EVOLVE TONIGHT, WE COULD HAVE STORMS ONGOING  
DURING THE MORNING COMMUTE TOMORROW, WITH THE EFFECTIVE BOUNDARY  
FUELING CONTINUED STORMS THROUGHOUT THE DAY. HOWEVER, THE HIGHEST  
CHANCE FOR STORMS OVER THE LOCAL AREA WILL ONCE AGAIN BE DURING THE  
EVENING WHEN ANOTHER SHORTWAVE DIGS ACROSS THE UPPER OHIO VALLEY,  
PROVIDING A LIFTING MECHANISM AND BETTER (30-40 KT) DEEP LAYER SHEAR  
TO SUSTAIN CONVECTION. UNCERTAINTY SURROUNDS HOW MUCH OF A SEVERE  
RISK WILL ACCOMPANY THIS ACTIVITY GIVEN POTENTIAL FOR WIDESPREAD  
CLOUDS AND EARLY-DAY STORMS WHICH COULD LIMIT INSTABILITY, BUT IF WE  
SEE ENOUGH BREAKS OF SUNSHINE THE ENVIRONMENT WOULD CERTAINLY BE  
FAVORABLE, ONCE AGAIN, FOR ONE OR MORE MCSS CAPABLE OF DAMAGING  
WINDS AND TORRENTIAL RAINFALL LEADING TO LOCALIZED FLASH FLOODING.  
AT THIS TIME, SPC HAS AREAS WEST OF I-65 OUTLOOKED IN A LEVEL 2 OF 5  
(SLIGHT RISK) FOR SEVERE WEATHER.  
 
***** THURSDAY THROUGH MONDAY *****  
 
GLOBAL DETERMINISTIC MODELS AND THEIR RESPECTIVE ENSEMBLES SUGGEST  
RIDGING SHOULD BUILD OVER THE MIDWEST AND OHIO VALLEY INTO THE  
WEEKEND, SUGGESTING A DOWNWARD TREND IN PRECIPITATION CHANCES AND  
CONTINUED WARM, MUGGY CONDITIONS. HOWEVER, PARTICULARLY THURSDAY AND  
FRIDAY, WE REMAIN PRECIOUSLY CLOSE TO THE RING OF FIRE - THE  
NORTHEAST PERIPHERY OF THE RIDGE WHERE THE BEST OVERLAP OF  
INSTABILITY AND DEEP LAYER SHEAR WILL FAVOR MCS ACTIVITY. STORM  
CHANCES, AROUND 40-50% NORTHEAST OF A JASPER, INDIANA TO SOMERSET,  
KENTUCKY LINE THURSDAY INTO FRIDAY, WILL FINALLY DROP BELOW 20% BY  
SATURDAY.  
 

 
   
AVIATION /18Z TAFS THROUGH 00Z THURSDAY/
 
 
ISSUED AT 125 PM EDT TUE AUG 11 2026  
 
A ROUND OF SCATTERED SHOWERS AND STORMS WILL MOVE INTO THE REGION  
THIS EVENING BRINGING STRONG WINDS AND LOWERED VIS. THE HIGHEST  
CONFIDENCE FOR STRONG STORMS WILL BE FOR LEX AND RGA. IF THE SYSTEMS  
TRACKS MORE WESTWARD, SDF AND HNB COULD GET SOME STRONGER STORMS AS  
WELL. PROB30S HAVE BEEN ADDED TO ALL SITES, EXCEPT BWG, DUE TO THIS  
UNCERTAINTY, BUT TO RELY THE MOST LIKELY TIMEFRAME. LEX AND RGA ARE  
EXPECTED TO SEE MULTIPLE ROUNDS OF RAIN TONIGHT INTO THE EARLY  
MORNING HOURS. SITES SHOULD EXPECT SOME VARIABILITY IN WIND  
DIRECTION WITH ANY OUTFLOW GUSTS. CEILINGS ARE EXPECTED TO STAY VFR  
,OUTSIDE OF POSSIBLE LOWERED STORM BASES, FOR THE REMAINED OF THE  
TAF PERIOD.  
 

 
   
LMK WATCHES/WARNINGS/ADVISORIES
 
 
KY...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR KYZ023-026-061-  
070>073.  
FLOOD WATCH THROUGH WEDNESDAY MORNING FOR KYZ032-033-035>037-  
040>043-048-049-057.  
IN...HEAT ADVISORY UNTIL 9 PM EDT /8 PM CDT/ THIS EVENING FOR  
INZ076-083-084-089.  
FLOOD WATCH THROUGH WEDNESDAY MORNING FOR INZ079.  
 

 
 

 
 
UPDATE...BJS  
SHORT TERM...JRB  
LONG TERM...JRB  
AVIATION...CAL  
 
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