Alert archive / Kentucky / Mesoscale Discussions in 2021
Mesoscale Discussion 1511
The Storm Prediction Center issued this mesoscale discussion at Aug 13, 2021, 1:13 PM EDT for 4 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 13, 2021, 1:13 PM EDT (17:13 UTC)
- Expired
- Aug 13, 2021, 3:15 PM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch possible
- Chance of a watch
- 40%
All 143 counties
Clark County, IN, Crawford County, IN, Dearborn County, IN, Decatur County, IN, Dubois County, IN, Floyd County, IN, Franklin County, IN, Harrison County, IN, Jackson County, IN, Jefferson County, IN, Jennings County, IN, Lawrence County, IN, Ohio County, IN, Orange County, IN, Perry County, IN, Pike County, IN, Ripley County, IN, Scott County, IN, Spencer County, IN, Switzerland County, IN, Union County, IN, Warrick County, IN, Washington County, IN, Anderson County, KY, Bath County, KY, Boone County, KY, Bourbon County, KY, Boyd County, KY, Boyle County, KY, Bracken County, KY, Breckinridge County, KY, Bullitt County, KY, Campbell County, KY, Carroll County, KY, Carter County, KY, Clark County, KY, Daviess County, KY, Elliott County, KY, Estill County, KY, Fayette County, KY, Fleming County, KY, Franklin County, KY, Gallatin County, KY, Garrard County, KY, Grant County, KY, Grayson County, KY, Greenup County, KY, Hancock County, KY, Hardin County, KY, Harrison County, KY, Henry County, KY, Jefferson County, KY, Jessamine County, KY, Johnson County, KY, Kenton County, KY, Larue County, KY, Lawrence County, KY, Lee County, KY, Lewis County, KY, Madison County, KY, Magoffin County, KY, Marion County, KY, Martin County, KY, Mason County, KY, Meade County, KY, Menifee County, KY, Mercer County, KY, Montgomery County, KY, Morgan County, KY, Nelson County, KY, Nicholas County, KY, Oldham County, KY, Owen County, KY, Pendleton County, KY, Powell County, KY, Robertson County, KY, Rowan County, KY, Scott County, KY, Shelby County, KY, Spencer County, KY, Trimble County, KY, Washington County, KY, Wolfe County, KY, Woodford County, KY, Adams County, OH, Athens County, OH, Belmont County, OH, Brown County, OH, Butler County, OH, Clark County, OH, Clermont County, OH, Clinton County, OH, Coshocton County, OH, Fairfield County, OH, Fayette County, OH, Franklin County, OH, Gallia County, OH, Greene County, OH, Guernsey County, OH, Hamilton County, OH, Harrison County, OH, Highland County, OH, Hocking County, OH, Jackson County, OH, Lawrence County, OH, Licking County, OH, Madison County, OH, Meigs County, OH, Monroe County, OH, Montgomery County, OH, Morgan County, OH, Muskingum County, OH, Noble County, OH, Perry County, OH, Pickaway County, OH, Pike County, OH, Preble County, OH, Ross County, OH, Scioto County, OH, Vinton County, OH, Warren County, OH, Washington County, OH, Cabell County, WV, Calhoun County, WV, Clay County, WV, Doddridge County, WV, Gilmer County, WV, Harrison County, WV, Jackson County, WV, Kanawha County, WV, Lewis County, WV, Lincoln County, WV, Marshall County, WV, Mason County, WV, Pleasants County, WV, Putnam County, WV, Ritchie County, WV, Roane County, WV, Tyler County, WV, Wayne County, WV, Wetzel County, WV, Wirt County, WV, Wood County, WV
The radar
The Cincinnati radar (KILN), 99 km from the middle of the area, began a volume at 17:16 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Cncnati-Daytn, OH (KILN), launched 12:00Z, 5.2 hours before the alert went out and 101 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 1416 J/kg
- Mixed-layer CIN
- -55 J/kg
- Mixed-layer LCL
- 1025 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 91 m²/s²
- 0-3 km storm-relative helicity
- 109 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
879
ACUS11 KWNS 131713
SWOMCD
SPC MCD 131713
WVZ000-PAZ000-OHZ000-KYZ000-INZ000-131915-
Mesoscale Discussion 1511
NWS Storm Prediction Center Norman OK
1213 PM CDT Fri Aug 13 2021
Areas affected...Ohio River Valley
Concerning...Severe potential...Watch possible
Valid 131713Z - 131915Z
Probability of Watch Issuance...40 percent
SUMMARY...Thunderstorms are expected to increase in coverage through
the Ohio River Valley as daytime heating continues amid weak
capping. Storms may be capable of damaging winds and severe hail,
and a watch may be needed as storm coverage increases this
afternoon.
DISCUSSION...Isolated convective towers and weak thunderstorms are
noted in recent regional radar and GOES imagery. This activity is
largely being driven by strong daytime heating as low-level parcels
reach their convective temperatures in the upper 80s and low 90s.
Ample boundary layer moisture ahead of a diffuse cold front further
to the northwest is supporting MLCAPE values upwards of 2000-2500
MLCAPE, which is being utilized early this afternoon thanks to
negligible inhibition. Thunderstorm coverage will likely increase
through the early to mid afternoon hours as convection develops
along outflow from ongoing storms and in the vicinity of a weak MCV
noted in satellite imagery over southern/southeast IN. Despite ample
instability, effective shear is relatively modest (near 25 knots),
and will likely only support loose organization of storm clusters.
However, damaging winds and severe hail will be possible with any
stronger updraft pulses and/or organized outflows. Trends will
continue to be monitored, and a watch may be needed if convective
coverage increases enough to pose a substantial severe threat.
..Moore/Hart.. 08/13/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PBZ...RLX...CLE...JKL...ILN...LMK...IND...PAH...
LAT...LON 38468726 39768482 40448223 40378097 39848038 39168028
38248123 37598288 37458479 37358588 37478658 37618706
37978734 38468726SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 12, 8:37 PM EDT | Severe Thunderstorm Watch | SPC | Posey | 4 hr |
| Aug 12, 8:20 PM EDT | Mesoscale Discussion | SPC | Ballard, Crittenden, Livingston, McCracken, Union | 85 min |
| Aug 12, 10:55 PM EDT | Mesoscale Discussion | SPC | Ballard, Carlisle, Fulton, Hickman, Livingston, McCracken and 1 more | 95 min |
| Aug 13, 4:46 PM EDT | Severe Thunderstorm Watch | SPC | Ashland, Athens, Belmont, Carroll, Columbiana, Coshocton and 21 more | 5 hr |
| Aug 13, 7:49 PM EDT | Mesoscale Discussion | SPC | Carroll, Columbiana, Coshocton, Harrison, Holmes, Jefferson and 6 more | 56 min |
| Aug 13, 12:33 PM EDT | Mesoscale Discussion | SPC | Berkeley, Hampshire, Hardy, Jefferson, Morgan | 87 min |
| Aug 13, 1:11 PM EDT | Severe Thunderstorm Watch | SPC | Berkeley, Jefferson | 7 hr |
Nearby
Mesoscale Discussions in Kentucky, 2021Mesoscale Discussions in Ohio, 2021Mesoscale Discussions in Indiana, 2021Every mesoscale discussion in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.