Surface high pressure was solidly over central Kentucky, but given the moist atmosphere and temperatures in the 90s, afternoon and evening thunderstorms resulted in a variety of severe thunderstorm damage across central Kentucky. Reports ranged from flash flooding and wind damage to a couple of lightning fires.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS LMK wrote it up.
Surface high pressure was solidly over central Kentucky, but given the moist atmosphere and temperatures in the 90s, afternoon and evening thunderstorms resulted in a variety of severe thunderstorm damage across central Kentucky. Reports ranged from flash flooding and wind damage to a couple of lightning fires.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Louisville, KY wrote its last area forecast discussion before the first event at Aug 25, 2:21 PM EST, 15 minutes earlier.
Area Forecast Discussion National Weather Service Louisville KY 321 PM EDT Wed Aug 25 2021 .Short Term...(This evening through Thursday) Issued at 300 PM EDT Wed Aug 25 2021 Showers and storms are currently across our northern CWA, driven by forcing from weak 700-400 PVA associated with a weak mid-level shortwave and remnant sfc outflow boundaries in a supportive environment where PWATs are 1.6-1.9". Daytime heating has allowed SBCAPE to increase to 1500-3000 J/kg along with steep low level lapse rates around 7.5-8 C/km. Clusters of strong storms are possible through this afternoon and evening mainly north of the Cumberland Pkwy, capable of gusty winds and frequent lightning. With weak flow aloft, storm motions will remain rather slow, allowing for extended residence time of heavy rainfall on a given area. Some localized nuisance flooding may be possible due to the high PWAT airmass in place. Scattered convection will be possible through the rest of this afternoon and evening hours before peak heating is lost. Confidence remains limited in the short term given the poor performance of CAMs initializing so far today. With the sfc high over the region, expect the pre-dawn hours to have some patchy fog as light winds accompany low level moisture. Could see some dense fog in spots that pick up some rainfall this afternoon. Patchy fog should burn off around sunrise, leading to another hot and muggy day with increased precip chances. Upper level pattern will continue to feature the upper level ridge across the central US, with a deep East Coast high pressure system that will continue to filter moisture-rich Gulf air into our region. 1000-850mb thicknesses indicate temps will once again be in the low to mid 90s. Latest guidance blend did drop tomorrow's high forecast a degree or two, which seems reasonable given the increased cloud coverage and PoPs expected tomorrow. Generally speaking, areas east of I-65 will range between 89-93, and areas west of I-65 in the 90- 95 range. Heat indices will once again be in the 100-104 degree range across southern IN and KY counties west of I-65. Our Bluegrass region may have heat indices below 100. The weak mid-level shortwave will be just east of the CWA by tomorrow afternoon, but given the high PWAT environment and afternoon heating allowing our region to destabilize to roughly 1500- 3000 J/kg again, should be enough forcing to fire off scattered- numerous showers and storms tomorrow afternoon. Could begin to see convective initiation around 19z. With another day of weak flow aloft, very little shear will limit storm motions and organization. Storm motions may only be around 15kts or so, if model soundings hold true. Soundings showing K Index values around 40 suggest torrential rainfall will be possible, so will have to watch for isolated flooding issues (OHRFC 1-hr FFG is slightly above 2"). Convective activity should diminish during the early evening hours as peak heating is lost. && .Long Term...(Thursday night through Wednesday) Issued at 315 PM EDT Wed Aug 25 2021 ==================================== Synoptic Overview ==================================== Persistent mid-level ridge centered across the SW Atlantic will continue to have a strong influence on the weather pattern across the Ohio Valley this weekend and into next week. The ridge may remain just far enough east to allow a plume of moisture laden air to come into the Ohio Valley from the southwest. Overall, this is a typical late summertime pattern for the area. The overall set up will feature mainly diurnally driven convection each afternoon/evening this weekend. Moving into next week, a stronger mid-level trough axis moving through in the westerlies to the north may be strong enough to knock down the ridge and allow a front to drive southward into the region. At the same time, a tropical disturbance now over the southern Caribbean is forecast to move northwestward and develop into a tropical cyclone. This tropical cyclone may impact a portion of the Gulf coast states early next and there is a possibility that some of the remnants may flow northward into the Tennessee and Ohio Valleys around the middle of next week. ==================================== Model Trends/Discussion/Preference ==================================== Overall model agreement remains decent through the weekend, but significant differences remain on the table for next week, due to uncertainty in many variables of the forecast process. In general, I expect the short term/high res models to struggle with convection in the near term. The overall pattern depicted by the models suggest mainly diurnally driven convection due to afternoon heating. However, various left over boundaries on the mesoscale or even beta scale will make defining an area difficult. The models do agree that heights may rise a bit on Saturday as troughing develops out to the west. We'll still have plenty of low- level moisture to work with, but with the higher heights, model soundings across the region all show a bit more capping. As heights fall a bit on Sun/Mon, we should see afternoon/evening coverage increase once again. Moving into next week, the global models all show a current tropical disturbance over the Caribbean will move northwest and into the western half of the Gulf early next week. While the deterministic runs aim for the TX/LA border with a possible landfall, an examination of the ensembles shows a very wide range of tracks and intensities for this system. In fact, the ensemble spread shows that anywhere from Brownsville, TX all the way over to the FL/AL line could be under the gun for a late August tropical cyclone. Beyond the land fall, there is a possibility that the remnants could come further north into the Ohio Valley. The Canadian GEM and the 25/00Z and 25/12Z Euro suggest this, though the 12Z GFS isn't on board at this time. ==================================== Sensible Weather Impacts ==================================== ...Heavy Rainfall Possible Next Week... For the Friday-Sunday period, very warm and humid conditions will continue across the region. Scattered afternoon/evening showers and storms are expected on Friday with a slightly lesser amount of coverage for Saturday. Temperatures during this period will feature highs in the upper 80s to the lower 90s with overnight lows in the upper 60s to the lower 70s. Shower and thunderstorm coverage looks to increase a bit as we get into the Sunday and Monday time frame as a mid-level trough axis swings through the Great Lakes and flattens out the ridge. At the same time, a slow moving frontal boundary will drop into the region from the north. This front should serve as a focus for renewed convective development across the region. Given the moisture available, heavy rainfall and possibly some local flooding issues may develop. Given the relatively good agreement, have increased PoPs in the Sun-Mon time frame a bit over the blend. Will also be lowering temps here with mainly upper 80s expected. For the Tue-Wed period, there remains a LOT of uncertainty on where the remnants of the tropical system in the Gulf will end up. There has been a signal in the GEM and Euro data that the remnants could come northward and merge along the front pushing through the Ohio Valley. That certainty is a plausible scenario and one that could bring very heavy rainfall and possible flooding to the region. At the same time, the ensembles continue have quite a bit of spread through the period. As such, I expect we'll see a wide range of solutions over the coming days as the system develops and additional data is collected over the Gulf due to hurricane hunter flights. ==================================== Forecast Confidence ==================================== Thursday Night - Saturday Night : Medium confidence on all elements Sunday - Monday: Low-medium confidence on all elements Tuesday - Wednesday: Low confidence on all elements && .Aviation...(18Z TAF Issuance) Issued at 1220 PM EDT Wed Aug 25 2021 Mid and high level cloud debris from early morning convection continues to cover areas along and north of I-64. Beginning to see scattered cu develop as temperatures warm into the low 90s. There remains a slight chance of a shower or thunderstorm popping up across southern Indiana or northern Kentucky. This could impact SDF, HNB, or LEX, but confidence remains low and will keep TAFs dry. Winds will remain light and variable as a surface high works through the region today. Guidance is strongly hinting at some fog across the region tomorrow morning, so included MVFR vis restrictions at HNB, LEX, and BWG for the pre-dawn hours. && .LMK WATCHES/WARNINGS/ADVISORIES... IN...None. KY...None. && Short Term...CJP Long Term...MJ Aviation...CJP
Hazardous Weather Outlook National Weather Service Louisville KY 329 PM EDT Wed Aug 25 2021 INZ076>079-083-084-089>092-KYZ023>043-045>049-053>057-061>067- 070>078-081-082-261930- Orange-Washington-Scott-Jefferson-Dubois-Crawford-Perry-Harrison- Floyd-Clark-Hancock-Breckinridge-Meade-Ohio-Grayson-Hardin-Bullitt- Oldham-Trimble-Henry-Shelby-Franklin-Spencer-Anderson-Woodford- Fayette-Bourbon-Nicholas-Nelson-Mercer-Jessamine-Larue-Marion-Boyle- Garrard-Madison-Butler-Edmonson-Hart-Green-Taylor-Casey-Lincoln- Logan-Warren-Simpson-Allen-Barren-Monroe-Metcalfe-Adair-Russell- Cumberland-Clinton- Including the cities of Paoli, Salem, Scottsburg, Madison, Jasper, English, Tell City, Corydon, New Albany, Jeffersonville, Lewisport, Hawesville, Hardinsburg, Brandenburg, Hartford, Leitchfield, Elizabethtown, Shepherdsville, Louisville, La Grange, Bedford, Milton, New Castle, Shelbyville, Frankfort, Georgetown, Cynthiana, Taylorsville, Lawrenceburg, Versailles, Lexington, Paris, Carlisle, Bardstown, Springfield, Harrodsburg, Nicholasville, Winchester, Hodgenville, Lebanon, Danville, Lancaster, Richmond, Morgantown, Brownsville, Horse Cave, Greensburg, Campbellsville, Liberty, Stanford, Russellville, Bowling Green, Franklin, Providence, Scottsville, Glasgow, Tompkinsville, Edmonton, Columbia, Jamestown, Burkesville, and Albany 329 PM EDT Wed Aug 25 2021 /229 PM CDT Wed Aug 25 2021/ This hazardous weather outlook is for portions of south central Indiana and Central Kentucky. .DAY ONE...Tonight. Scattered showers and storms will continue this afternoon and early evening. Storms are capable of gusty winds, frequent lightning, and heavy rainfall. Slow storm motions may lead to some localized flooding issues. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. Heat index values will generally range from 100 to 105 degrees in the afternoon Wednesday and Thursday along and west of I-65. Scattered storms are forecast each afternoon and evening. Locally heavy rainfall and lightning are the primary storm hazards. A cold front approaching Sunday and Monday may bring more widespread activity. .SPOTTER INFORMATION STATEMENT... Spotter activation will likely not be needed at least through the weekend. CJP/MJ
Special Weather Statement
National Weather Service Louisville KY
200 PM EDT Wed Aug 25 2021
INZ077-078-251845-
Washington IN-Scott IN-
200 PM EDT Wed Aug 25 2021
...A strong thunderstorm will impact portions of west central Scott
and northeastern Washington Counties through 245 PM EDT...
At 200 PM EDT, Doppler radar was tracking a strong thunderstorm near
Brownstown, moving southeast at 10 mph.
HAZARD...Winds in excess of 40 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
This storm will remain over mainly rural areas of northeastern
Washington and west central Scott Counties, including the following
locations... New Philadelphia, Kossuth, Plattsburg, Canton,
Harristown and Little York.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 3876 8603 3877 8602 3876 8601 3877 8598
3875 8598 3876 8596 3875 8595 3876 8594
3875 8592 3875 8590 3873 8588 3874 8585
3869 8579 3856 8610 3878 8621 3877 8620
3878 8618 3876 8613 3878 8609
TIME...MOT...LOC 1800Z 326DEG 7KT 3880 8610
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH
MJSpecial Weather Statement
National Weather Service Louisville KY
207 PM EDT Wed Aug 25 2021
KYZ042-043-251830-
Bourbon KY-Nicholas KY-
207 PM EDT Wed Aug 25 2021
...A strong thunderstorm will impact portions of east central Bourbon
and southeastern Nicholas Counties through 230 PM EDT...
At 207 PM EDT, Doppler radar was tracking a strong thunderstorm near
Sharpsburg, moving east at 15 mph.
HAZARD...Winds in excess of 40 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
This storm will remain over mainly rural areas of east central
Bourbon and southeastern Nicholas Counties, including the following
locations... Plum, Sprout, East Union, Weston and Moorefield.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 3830 8385 3819 8398 3818 8399 3815 8404
3832 8405 3835 8387 3835 8386 3833 8386
3833 8385 3834 8384 3832 8385 3831 8383
TIME...MOT...LOC 1807Z 268DEG 13KT 3824 8396
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH
MJSpecial Weather Statement
National Weather Service Louisville KY
215 PM EDT Wed Aug 25 2021
KYZ037-251900-
Harrison KY-
215 PM EDT Wed Aug 25 2021
...A strong thunderstorm will impact portions of Harrison County
through 300 PM EDT...
At 215 PM EDT, Doppler radar was tracking a strong thunderstorm 8
miles south of Falmouth, moving southeast at 20 mph.
HAZARD...Winds in excess of 40 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Cynthiana.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 3831 8431 3852 8448 3854 8448 3853 8446
3854 8443 3857 8441 3858 8422 3857 8420
3856 8422 3855 8421 3856 8419 3854 8416
3853 8418 3850 8418 3850 8416 3849 8417
3848 8415 3848 8413 3846 8411
TIME...MOT...LOC 1815Z 318DEG 15KT 3855 8435
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH
MJSpecial Weather Statement
National Weather Service Louisville KY
216 PM EDT Wed Aug 25 2021
KYZ033>035-251900-
Shelby KY-Henry KY-Franklin KY-
216 PM EDT Wed Aug 25 2021
...A strong thunderstorm will impact portions of northeastern Shelby,
southeastern Henry and Franklin Counties through 300 PM EDT...
At 216 PM EDT, Doppler radar was tracking a strong thunderstorm 10
miles east of New Castle, moving southeast at 15 mph.
HAZARD...Winds in excess of 40 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Frankfort.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 3846 8495 3844 8496 3843 8496 3843 8494
3846 8493 3845 8491 3844 8493 3842 8488
3838 8490 3837 8487 3836 8487 3835 8481
3828 8473 3828 8474 3814 8493 3836 8513
3848 8497
TIME...MOT...LOC 1816Z 318DEG 15KT 3838 8499
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH
MJSpecial Weather Statement
National Weather Service Louisville KY
254 PM EDT Wed Aug 25 2021
KYZ043-251930-
Nicholas KY-
254 PM EDT Wed Aug 25 2021
...A strong thunderstorm will impact portions of eastern Nicholas
County through 330 PM EDT...
At 254 PM EDT, Doppler radar was tracking a strong thunderstorm near
Carlisle, moving southeast at 25 mph.
HAZARD...Winds in excess of 30 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
This storm will remain over mainly rural areas of eastern Nicholas
County, including the following locations... Sprout, East Union,
Weston, Moorefield, Pleasant Valley and Myers.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 3830 8385 3821 8396 3827 8407 3842 8395
3839 8393 3836 8392 3836 8389 3835 8390
3836 8387 3835 8387 3835 8386 3833 8386
3834 8384 3832 8385 3831 8383
TIME...MOT...LOC 1854Z 299DEG 23KT 3832 8393
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...30 MPH
MJSpecial Weather Statement
National Weather Service Louisville KY
316 PM EDT Wed Aug 25 2021
KYZ030-031-034-038-252000-
Jefferson KY-Oldham KY-Shelby KY-Spencer KY-
316 PM EDT Wed Aug 25 2021
...A strong thunderstorm will impact portions of northwestern
Spencer, south central Oldham, western Shelby and east central
Jefferson Counties through 400 PM EDT...
At 316 PM EDT, Doppler radar was tracking a strong thunderstorm near
Middletown, moving east at 15 mph.
HAZARD...Winds in excess of 40 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Shelbyville.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 3827 8513 3802 8525 3810 8544 3811 8543
3812 8543 3811 8546 3815 8556 3833 8548
TIME...MOT...LOC 1916Z 290DEG 13KT 3822 8544
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH
MJThe Louisville radar (KLVX), 68 km away, was scanning. The volume nearest the first event began at 19:33 UTC.
3 thunderstorm wind, 2 lightning, 1 hail, 1 flash flood. Local standard time, as filed.
There was suspected microburst damage along Dover Road. One outdoor pavilion was demolished. Multiple large branches were down, and a tree was uprooted. There was also a large building with a 14 foot Overhead Door that was damaged.
There was a structure fire caused by a lightning strike. Cost of damage is unknown.
There were 15 power lines down in Louisville. The first one came down around 7:52 PM.
The report was on social media.
There were around 12 trees down and one structure collapse in Louisville.
There was a commercial building on fire after a lightning strike. The cost of damage is unknown.
Two cars were stranded in flood waters. Cost of damage is unknown.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Kentucky in 2021Every state in 2021This day in weather historyWarnings in Kentucky, August 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 981064, 981063, 981066, 981065, 981067, 981068, 981062.