589
FXUS63 KLMK 110537
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
137 AM EDT SAT JUL 11 2026
..UPDATED AVIATION DISCUSSION
KEY MESSAGES
* THERE IS A LEVEL 1 OF 5 (MARGINAL) RISK FOR SEVERE WEATHER
BEGINNING AROUND 6PM EDT IN SOUTHERN KENTUCKY, AND FROM MIDNIGHT
TO 4 AM IN OTHER AREAS MAINLY WEST OF I-65. THE PRIMARY HAZARD
WOULD BE DAMAGING WIND GUSTS.
* IN ADDITION, THUNDERSTORMS TONIGHT WILL BRING A LEVEL 2 OF 4
(SLIGHT) RISK FOR EXCESSIVE RAINFALL, WITH POCKETS OF OVER 4
INCHES POTENTIALLY RESULTING IN FLASH FLOODING.
* ANOTHER ROUND OF STORMS IS LIKELY (50-80% CHANCE) SATURDAY EVENING
THROUGH SATURDAY NIGHT. THESE STORMS WILL ALSO POSE A RISK FOR
SEVERE WEATHER AND EXCESSIVE RAINFALL.
* TYPICAL SUMMERTIME TEMPERATURES WITH DAILY CHANCES FOR
ISOLATED/SCATTERED AFTERNOON SHOWERS AND STORMS IS FAVORED FOR
MUCH OF NEXT WEEK.
SHORT TERM /THROUGH SUNDAY/
ISSUED AT 201 PM EDT FRI JUL 10 2026
***** TONIGHT *****
EARLY FRIDAY AFTERNOON, MRMS 12 HOUR RADAR ESTIMATED PRECIPITATION
RANGES ANYWHERE FROM LESS THAN A TENTH OF AN INCH ACROSS SOME
LOCATIONS EAST OF I-75 TO MORE MORE THAN 3 INCHES IN A SWATH
IMMEDIATELY SOUTH OF I-64 AND IN A FEW OTHER LOCALIZED POCKETS
ACROSS CENTRAL/WEST-CENTRAL KY. IN THE WAKE OF AN MCV ASSOCIATED
WITH LAST NIGHT'S PRECIP EVENT, WEAK SUBSIDENCE IS SUPPRESSING
CONVECTION, WITH ONLY A FEW LIGHT SHOWERS OBSERVED ACROSS THE AREA
AT THIS TIME. RAP MESOANALYSIS REVEALS A SURFACE LOW BENEATH A MID
LEVEL SHORTWAVE OVER NORTHERN MISSOURI, WITH A QUASISTATIONARY FRONT
EXTENDING EAST ACROSS IL/IN/OH. ALONG AND SOUTH OF THAT FRONT,
ADDITIONAL THUNDERSTORMS ARE EXPECTED TO FIRE OVER PORTIONS OF
MISSOURI AND ILLINOIS THIS EVENING, AND SUBSEQUENTLY RIDE EASTWARD
INTO OUR AREA OVERNIGHT, LINGERING THROUGH MUCH OF THE MORNING
TOMORROW. WITH A 20-30 KT LLJ OVER THE AREA, CORFIDI UPSHEAR VECTORS
OF 5-10 KT SUGGEST BACK-BUILDING POTENTIAL, AND THIS SCENARIO IS
DEPICTED IN SEVERAL CAMS - WITH THE AXIS OF HEAVIEST RAINFALL MOST
LIKELY TO OCCUR SOMEWHERE ACROSS EITHER SOUTH/WEST KY OR TENNESSEE.
THIS IS WHERE THE ECMWF EXTREME FORECAST INDEX (EFI) SHIFT OF TAILS
(SOT) IS PRESENT, SUGGESTING THE TOP 10% OF ENSEMBLE MEMBERSHIP IS
ABOVE THE 99TH PERCENTILE OF MODEL CLIMATOLOGY, OR IN SIMPER TERMS -
THERE IS NOTABLE POTENTIAL FOR A SIGNIFICANT/IMPACTFUL EVENT. IN
TERMS OF ACTUAL RAINFALL AMOUNTS, HREF ENSEMBLE MAX THROUGH TOMORROW
EVENING FEATURES SWATHS OF OVER 3 INCHES IN THOSE LOCATIONS, WITH A
FEW POCKETS OF SUCH HIGH AMOUNTS ALSO SHOWING UP FURTHER NORTH WHERE
A DEFORMATION ZONE COULD SET UP ON THE STABLE SIDE OF ANY MCS (WHERE
INSTABILITY IS WEAKER BUT WARM CLOUD PROCESSES DOMINATE, LEADING TO
EFFICIENT RAINFALL). THE MAIN WEATHER CONCERN TONIGHT INTO TOMORROW
WILL BE FLASH FLOODING, HOWEVER ANYTHING PRIOR TO ABOUT 2AM EDT
TONIGHT COULD ALSO POSE A RISK FOR GUSTY TO LOCALLY DAMAGING WINDS,
PARTICULARLY ACROSS SOUTHERN AND WESTERN PORTIONS OF THE COUNTY
WARNING AREA (CWA) WHERE AN SPC LEVEL 1 OF 5 (MARGINAL) RISK IS IN
PLACE.
***** SATURDAY AND SUNDAY *****
LIKE TODAY, A DIURNAL MINIMUM IN STORMS IS FORECAST TOMORROW, WITH A
20-40% CHANCE OF CONVECTION DURING THE LATE MORNING AND AFTERNOON
HOURS, BUT WITH ENOUGH HEATING THE ATMOSPHERE MAY DESTABILIZE ONCE
AGAIN TO FAVOR ANOTHER EVENING-EARLY OVERNIGHT SEVERE WEATHER RISK.
MESOSCALE PROCESSES WILL ONCE AGAIN DRIVE THE MAGNITUDE AND PRECISE
LOCATION OF THE HEAVY RAINFALL AND FLASH FLOODING RISK TOMORROW
NIGHT INTO EARLY SUNDAY, BUT THE POTENTIAL IS THERE FOR ANOTHER WAVE
OF LOCALLY HEAVY RAINFALL (3+ INCHES) GIVEN THE RICH DEEP MOISTURE
(PWATS > 2 INCHES AND "TALL, SKINNY" CAPE PROFILES) AND
REDEVELOPMENT OF A 25-35 KT WESTERLY LLJ.
GLOBAL MODELS AND THEIR RESPECTIVE ENSEMBLES ARE SLOW TO MOVE THE
CUT OFF LOW OUT OF HERE AS RIDGING ATTEMPTS TO NOSE IN FROM THE
NORTH, THOUGH FORTUNATELY THE BETTER DYNAMICS AND INSTABILITY FOR
HEAVY RAINFALL SHOULD SHIFT SOUTH OF THE LOCAL AREA BY SUNDAY.
STILL, THE AREA IS LIKELY TO SEE AT LEAST A FEW (20-40% COVERAGE)
DIURNALLY-DRIVEN POP-UP SHOWERS AND STORMS DURING THE AFTERNOON AND
EVENING. GIVEN THE ENVIRONMENT, HIGHLY LOCALIZED POCKETS OF HEAVY
(3+ INCHES) RAINFALL REMAIN A CONCERN, AND IF THESE FALL OVER
LOCATIONS THAT ALREADY RECEIVED ABUNDANT RAIN (AND HENCE HAVE A LOW
THRESHOLD FOR FLOODING), WE COULD HAVE A COUPLE HYDROLOGICAL ISSUES
ONCE AGAIN.
LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/
ISSUED AT 201 PM EDT FRI JUL 10 2026
THE SYNOPTIC PATTERN ACROSS THE CONUS WILL BECOME DOMINATED BY
EXPANSIVE UPPER RIDGING FOR AT LEAST THE FIRST HALF OF NEXT WEEK AS
A 600+ DM 500 MB HIGH SETS UP ACROSS THE NORTHERN PLAINS. WHILE THE
OHIO VALLEY WILL BE ON THE SOUTHEAST EDGE OF THIS UPPER RIDGE,
RESIDUAL MID- AND UPPER-LEVEL ENERGY FROM THIS WEEKEND'S STORM
SYSTEM IS EXPECTED TO MEANDER ACROSS THE TN/MID-MISS. VALLEYS FROM
SUNDAY THROUGH AT LEAST TUESDAY BEFORE DRIFTING FARTHER TO THE WEST.
AS THIS WEAK UPPER LOW REMAINS IN OUR VICINITY, MOISTURE LEVELS
SHOULD BE SEASONABLE IF NOT A BIT ABOVE CLIMATOLOGY, WITH ENSEMBLE
MEAN PW AROUND 1.5". MOISTURE WILL BE RICHER AS YOU GO TO THE SOUTH,
SUPPORTING HIGHER CHANCES FOR SHOWERS AND STORMS THROUGH EARLY NEXT
WEEK.
THERE IS SOME DISCREPANCY IN THE EXACT POSITION OF THE UPPER
DISTURBANCE EARLY NEXT WEEK, WITH THE ECMWF AND ITS ENSEMBLES
DISPLACED TO THE SOUTH OF THE GFS. THIS WILL IMPACT DAILY SHOWER AND
STORM CHANCES NEXT WEEK, ESPECIALLY AFTER MONDAY, WITH THE GFS
FAVORING A MORE UNSETTLED PATTERN WHILE THE ECMWF IS GENERALLY
DRIER. IF STORMS ARE ABLE TO DEVELOP EACH AFTERNOON, WEAK FLOW ALOFT
SHOULD LEAD TO MAINLY GARDEN-VARIETY, SLOW MOVING SUMMER STORMS WITH
MINIMAL SEVERE POTENTIAL. GIVEN THE LIKELY SLOW MOVEMENT OF STORMS,
A LINGERING HEAVY RAINFALL/FLOODING THREAT CAN'T BE RULED OUT,
THOUGH LIMITED COVERAGE OF STORMS SHOULD LIMIT THIS THREAT.
OTHERWISE, TEMPERATURES SHOULD BE FAIRLY SEASONABLE WITH HIGHS IN
THE UPPER 80S TO AROUND 90 AND LOWS IN THE UPPER 60S AND LOW 70S.
THURSDAY INTO NEXT WEEKEND, A MORE SUBSTANTIAL UPPER TROUGH IS
PROGGED TO DESCEND ACROSS THE EASTERN PART OF NORTH AMERICA. MEDIUM-
RANGE GUIDANCE STILL FEATURES QUITE A BIT OF SPREAD AS TO HOW MUCH
THIS FEATURE WILL BE ABLE TO PUSH THE UPPER RIDGE BACK TO THE WEST,
WHICH WILL IMPACT THE FORECAST FOR LATE NEXT WEEK INTO THE FOLLOWING
WEEKEND. IF THE TROUGH IS ABLE TO DIG MORE TO THE SOUTH/WEST, IT
WOULD BRING A FRONT DOWN INTO THE OHIO VALLEY THAT WOULD INCREASE
STORM CHANCES/COVERAGE THURSDAY INTO FRIDAY. HOWEVER, A MORE
RESILIENT UPPER RIDGE WOULD SUPPORT WARMER AND DRIER WEATHER OVER
THE SAME PERIOD.
AVIATION /06Z TAFS THROUGH 12Z SUNDAY/
ISSUED AT 137 AM EDT SAT JUL 11 2026
A WIDESPREAD AREA OF RAIN WITH SOME EMBEDDED THUNDERSTORMS ARE
CURRENTLY MAKING ITS WAY IN FROM THE WEST. MVFR CONDITIONS ARE
EXPECTED WITH THESE STORMS AND AREAS OF HEAVY RAIN. CEILINGS WILL
BEGIN TO LOWER WITH THE SYSTEM BORDERING MVFR WITH A SECONDARY LAYER
BELOW 3KFT. A BRIEF DRY PERIOD IS FORECASTED FOR EARLY AFTERNOON
WHEN CLOUDS WILL RETURN BKN/OVC100 BEFORE ANOTHER WAVE OF SHOWERS
AND STORMS MOVE IN BY TONIGHT.
LMK WATCHES/WARNINGS/ADVISORIES
KY...FLOOD WATCH THROUGH LATE TONIGHT FOR KYZ023>043-045>049-
053>057-061>067-070>078-081-082.
IN...FLOOD WATCH THROUGH LATE TONIGHT FOR INZ076>079-083-084-
089>092.
SHORT TERM...JRB
LONG TERM...CSG
AVIATION...CAL
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