Alert archive / Ohio / Mesoscale Discussions in 2021

Mesoscale Discussion 2004

December 11, 202122 counties in Indiana; 14 counties in Kentucky; 25 counties in Ohio

The Storm Prediction Center issued this mesoscale discussion at Dec 11, 2021, 12:08 AM EST for 22 counties in Indiana; 14 counties in Kentucky; 25 counties in Ohio. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued
Dec 11, 2021, 12:08 AM EST (05:08 UTC)
Expired
Dec 11, 2021, 1:15 AM EST
In force
67 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch likely
Chance of a watch
80%
All 61 counties

Dearborn County, IN, Decatur County, IN, Delaware County, IN, Fayette County, IN, Franklin County, IN, Hamilton County, IN, Hancock County, IN, Henry County, IN, Jay County, IN, Jefferson County, IN, Jennings County, IN, Madison County, IN, Marion County, IN, Ohio County, IN, Randolph County, IN, Ripley County, IN, Rush County, IN, Shelby County, IN, Switzerland County, IN, Tipton County, IN, Union County, IN, Wayne County, IN, Boone County, KY, Bracken County, KY, Campbell County, KY, Carroll County, KY, Gallatin County, KY, Grant County, KY, Harrison County, KY, Kenton County, KY, Lewis County, KY, Mason County, KY, Owen County, KY, Pendleton County, KY, Robertson County, KY, Trimble County, KY, Adams County, OH, Brown County, OH, Butler County, OH, Champaign County, OH, Clark County, OH, Clermont County, OH, Clinton County, OH, Darke County, OH, Fayette County, OH, Franklin County, OH, Greene County, OH, Hamilton County, OH, Highland County, OH, Logan County, OH, Madison County, OH, Miami County, OH, Montgomery County, OH, Pickaway County, OH, Pike County, OH, Preble County, OH, Ross County, OH, Scioto County, OH, Shelby County, OH, Union County, OH, Warren County, OH

The radar

The Cincinnati radar (KILN), 62 km from the middle of the area, began a volume at 05:06 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 00:00Z, 5.1 hours before the alert went out and 64 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.

Skew-T log-pSkew-T log-p diagram, Cncnati-Daytn, OH at 00:00Z on 2021-12-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Cncnati-Daytn, OH at 00:00Z on 2021-12-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 325 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
519 m above ground
0-6 km bulk shear
71 kt
0-1 km storm-relative helicity
325 m²/s²
0-3 km storm-relative helicity
431 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

385 
ACUS11 KWNS 110508
SWOMCD
SPC MCD 110508 
OHZ000-KYZ000-INZ000-110615-

Mesoscale Discussion 2004
NWS Storm Prediction Center Norman OK
1108 PM CST Fri Dec 10 2021

Areas affected...Eastern Indiana...western Ohio...and far northern
Kentucky.

Concerning...Severe potential...Watch likely 

Valid 110508Z - 110615Z

Probability of Watch Issuance...80 percent

SUMMARY...A downstream tornado watch is likely across portions of
eastern Indiana, western Ohio, and possibly northern Kentucky.

DISCUSSION...The low-level airmass is still a bit on the dry side
across portions of eastern Indiana and western Ohio where dewpoints
are in the upper 50s. However, low-level moisture advection is
forecast to increase dewpoints into the low 60s across this region
in the next 2 to 3 hours. This should be sufficient moisture to
continue a threat for damaging wind and a few tornadoes as storms
move out of central Indiana. Therefore, a downstream tornado watch
will likely be issued in the next 1 to 2 hours.

..Bentley/Grams.. 12/11/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...JKL...ILN...LMK...IWX...IND...

LAT...LON   40368613 40508463 40478370 40178280 39578275 38848286
            38398349 38368401 38318479 38618540 39528608 39958627
            40368613

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 10, 7:21 PM ESTTornado WatchSPCClark, Crawford, Dubois, Floyd, Harrison, Jefferson and 4 more10 hr
Dec 10, 8:18 PM ESTMesoscale DiscussionSPCBartholomew, Benton, Boone, Brown, Carroll, Cass and 37 more87 min
Dec 10, 8:47 PM ESTTornado WatchSPCBartholomew, Benton, Boone, Brown, Clay, Clinton and 24 more8 hr
Dec 10, 9:35 PM ESTMesoscale DiscussionSPCHarrison85 min
Dec 10, 10:36 PM ESTMesoscale DiscussionSPCVigo54 min
Dec 10, 11:25 PM ESTMesoscale DiscussionSPCBartholomew, Benton, Blackford, Boone, Brown, Carroll and 50 more95 min
Dec 11, 12:03 AM ESTTornado WatchSPCGibson, Pike, Posey, Spencer, Vanderburgh, Warrick5 hr
Dec 11, 12:20 AM ESTTornado WatchSPCAdams, Allen, Blackford, Carroll, Cass, Dearborn and 27 more6 hr
Dec 11, 12:28 AM ESTMesoscale DiscussionSPCClay, Daviess, Fountain, Gibson, Greene, Knox and 9 more92 min
Dec 11, 2:46 AM ESTMesoscale DiscussionSPCBartholomew, Brown, Daviess, Dearborn, Decatur, Delaware and 21 more59 min
Dec 10, 7:22 PM ESTMesoscale DiscussionSPCFulton, Graves, Hickman53 min
Dec 10, 8:41 PM ESTMesoscale DiscussionSPCFulton64 min
Dec 10, 9:48 PM ESTMesoscale DiscussionSPCCarlisle, Fulton, Graves, Hickman, Lyon, Marshall57 min
Dec 10, 10:48 PM ESTMesoscale DiscussionSPCCaldwell, Graves, Hopkins, Lyon, Marshall57 min
Dec 10, 11:09 PM ESTMesoscale DiscussionSPCBallard, Caldwell, Calloway, Carlisle, Crittenden, Fulton and 7 more96 min
Dec 10, 11:44 PM ESTMesoscale DiscussionSPCCaldwell, Grayson, Hopkins, McLean, Muhlenberg, Ohio61 min
Dec 11, 12:36 AM ESTMesoscale DiscussionSPCCalloway, Christian, Logan, Simpson, Todd, Trigg54 min
Dec 11, 12:53 AM ESTMesoscale DiscussionSPCBreckinridge, Bullitt, Grayson, Hardin, Jefferson, Meade and 3 more67 min
Dec 11, 2:02 AM ESTMesoscale DiscussionSPCAdair, Allen, Anderson, Barren, Bath, Bourbon and 51 more88 min
Dec 11, 2:05 AM ESTMesoscale DiscussionSPCBarren, Butler, Edmonson, Green, Hart, Logan and 2 more55 min
Dec 11, 2:27 AM ESTTornado WatchSPCAdair, Allen, Anderson, Barren, Bath, Bourbon and 51 more7 hr
Dec 11, 3:51 AM ESTMesoscale DiscussionSPCBoyle, Casey, Clark, Estill, Garrard, Jessamine and 4 more54 min
Dec 11, 6:32 AM ESTMesoscale DiscussionSPCBell, Breathitt, Clark, Clay, Estill, Jackson and 18 more88 min

Nearby

Mesoscale Discussions in Ohio, 2021Mesoscale Discussions in Indiana, 2021Mesoscale Discussions in Kentucky, 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.