Alert archive / Kentucky / Mesoscale Discussions in 2021
Mesoscale Discussion 948
The Storm Prediction Center issued this mesoscale discussion at Jun 13, 2021, 2:04 PM EDT for 13 counties in Indiana; 54 counties in Kentucky; Clermont County, Hamilton County, Ohio. It was in force for 56 min.
The area
The outline as issued.
The facts
- Issued
- Jun 13, 2021, 2:04 PM EDT (18:04 UTC)
- Expired
- Jun 13, 2021, 3:00 PM EDT
- In force
- 56 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
All 69 counties
Clark County, IN, Crawford County, IN, Dearborn County, IN, Floyd County, IN, Harrison County, IN, Jefferson County, IN, Jennings County, IN, Ohio County, IN, Perry County, IN, Ripley County, IN, Scott County, IN, Switzerland County, IN, Washington County, IN, Anderson County, KY, Bath County, KY, Boone County, KY, Bourbon County, KY, Boyle County, KY, Bracken County, KY, Breckinridge County, KY, Bullitt County, KY, Campbell County, KY, Carroll County, KY, Casey County, KY, Clark 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, Green County, KY, Hancock County, KY, Hardin County, KY, Harrison County, KY, Hart County, KY, Henry County, KY, Jackson County, KY, Jefferson County, KY, Jessamine County, KY, Kenton County, KY, Larue County, KY, Lincoln County, KY, Madison County, KY, Marion County, KY, Mason County, KY, Meade County, KY, Menifee County, KY, Mercer County, KY, Montgomery County, KY, Nelson County, KY, Nicholas County, KY, Oldham County, KY, Owen County, KY, Pendleton County, KY, Powell County, KY, Robertson County, KY, Rockcastle County, KY, Scott County, KY, Shelby County, KY, Spencer County, KY, Taylor County, KY, Trimble County, KY, Washington County, KY, Woodford County, KY, Clermont County, OH, Hamilton County, OH
The radar
The Louisville radar (KLVX), 72 km from the middle of the area, began a volume at 18:05 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 nearest sounding before it
Cncnati-Daytn, OH (KILN), launched 12:00Z, 6.1 hours before the alert went out and 187 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
- 802 J/kg
- Mixed-layer CIN
- -92 J/kg
- Mixed-layer LCL
- 1233 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 28 m²/s²
- 0-3 km storm-relative helicity
- 19 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
300
ACUS11 KWNS 131805
SWOMCD
SPC MCD 131804
KYZ000-OHZ000-INZ000-131900-
Mesoscale Discussion 0948
NWS Storm Prediction Center Norman OK
0104 PM CDT Sun Jun 13 2021
Areas affected...portions of southwest Ohio into far southern
Indiana and northern Kentucky
Concerning...Severe potential...Watch unlikely
Valid 131804Z - 131900Z
Probability of Watch Issuance...20 percent
SUMMARY...Storm coverage and intensification is expected over the
next few hours. Damaging gusts would be the primary threat wherever
a severe threat may materialize. Conditions are being monitored, but
a Severe Thunderstorm Watch issuance appears unlikely.
DISCUSSION...MRMS mosaic radar imagery shows a gradual increase in
convective coverage and intensity ahead of a weak, southward sagging
cold front across portions of the Ohio Valley, further aided by
modest upper support from a glancing 700 mb impulse evident via 17Z
mesoanalysis. Deep-layer flow fields are weak, with wind speeds
remaining generally below 30 kts below 300 mb. 5-5.5 C/km mid-level
lapse rates are also constraining CAPE to tall, skinny profiles.
Nonetheless, 70+ F surface dewpoints overspread by 7.5-8 C/km
low-level lapse rates contained within a heated, well-mixed boundary
layer are contributing to 2000-3000 J/kg MLCAPE.
Given the weak tropospheric flow/vertical shear and skinny but
high-magnitude CAPE profiles, short-lived but potentially robust
updraft development may occur through the afternoon. The strongest
updrafts may produce damaging, potentially severe gusts. Given
moderate to strong instability supporting short-lived storms, severe
coverage remains somewhat uncertain.
..Squitieri/Grams.. 06/13/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...JKL...ILN...LMK...IND...PAH...
LAT...LON 39308549 39278455 38918386 38298352 37768359 37298415
37118511 37208582 37418648 37658680 37938688 39308549SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 13, 12:50 PM EDT | Severe Thunderstorm Watch | SPC | Boyd, Greenup | 7 hr |
| Jun 13, 3:26 PM EDT | Mesoscale Discussion | SPC | Boyd, Greenup | 94 min |
| Jun 13, 4:31 PM EDT | Mesoscale Discussion | SPC | Bath, Boyd, Carter, Elliott, Fleming, Floyd and 11 more | 89 min |
| Jun 13, 4:56 PM EDT | Severe Thunderstorm Watch | SPC | Carter, Elliott, Floyd, Johnson, Lawrence, Martin and 1 more | 5 hr |
| Jun 13, 7:05 PM EDT | Mesoscale Discussion | SPC | Martin | 85 min |
| Jun 13, 12:13 PM EDT | Mesoscale Discussion | SPC | Belmont, Carroll, Columbiana, Guernsey, Harrison, Jefferson and 5 more | 2 hr |
Nearby
Mesoscale Discussions in Kentucky, 2021Mesoscale Discussions in Indiana, 2021Mesoscale Discussions in Ohio, 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.