Alert archive / Ohio / Severe Thunderstorm Watches in 2004

Severe Thunderstorm Watch 239

May 21, 200427 counties in Ohio

The Storm Prediction Center issued this severe thunderstorm watch at May 21, 2004, 4:25 PM EDT for 27 counties in Ohio. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 21, 2004, 4:25 PM EDT (20:25 UTC)
Expired
May 21, 2004, 10:00 PM EDT
In force
6 hr
Issued by
the Storm Prediction Center
All 27 counties

Athens County, OH, Auglaize County, OH, Champaign County, OH, Clark County, OH, Clinton County, OH, Darke County, OH, Delaware County, OH, Fairfield County, OH, Fayette County, OH, Franklin County, OH, Greene County, OH, Hocking County, OH, Licking County, OH, Logan County, OH, Madison County, OH, Mercer County, OH, Miami County, OH, Montgomery County, OH, Muskingum County, OH, Perry County, OH, Pickaway County, OH, Preble County, OH, Ross County, OH, Shelby County, OH, Union County, OH, Vinton County, OH, Warren County, OH

The radar

The Cincinnati radar (KILN), 69 km from the middle of the area, began a volume at 20:26 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.

Warnings issued inside it

16 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 21, 4:43 PM EDTSevere Thunderstorm WarningILNChampaign, Logan62 min
May 21, 5:00 PM EDTSevere Thunderstorm WarningILNLicking60 min
May 21, 5:05 PM EDTSevere Thunderstorm WarningILNFranklin55 min
May 21, 5:10 PM EDTSevere Thunderstorm WarningILNMadison50 min
May 21, 5:11 PM EDTTornado WarningILNLicking34 min
May 21, 5:14 PM EDTSevere Thunderstorm WarningPBZMuskingum61 min
May 21, 5:36 PM EDTSevere Thunderstorm WarningILNDarke39 min
May 21, 5:40 PM EDTFlash Flood WarningPBZMuskingum3 hr
May 21, 5:51 PM EDTFlash Flood WarningRLXPerry3 hr
May 21, 5:52 PM EDTFlash Flood WarningILNShelby83 min
May 21, 6:21 PM EDTSevere Thunderstorm WarningILNPickaway39 min
May 21, 6:34 PM EDTSevere Thunderstorm WarningILNClark41 min
May 21, 6:44 PM EDTFlash Flood WarningILNFranklin2 hr
May 21, 6:47 PM EDTFlash Flood WarningRLXAthens118 min
May 21, 6:51 PM EDTSevere Thunderstorm WarningRLXAthens39 min
May 21, 7:49 PM EDTSevere Thunderstorm WarningILNFayette41 min

The nearest sounding before it

Cncnati-Daytn, OH (KILN), launched 12:00Z, 8.4 hours before the alert went out and 68 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 12:00Z on 2004-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2750 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Cncnati-Daytn, OH at 12:00Z on 2004-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 114 square meters per square second.193958Sfc1 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
2750 J/kg
Mixed-layer CIN
-38 J/kg
Mixed-layer LCL
666 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
114 m²/s²
0-3 km storm-relative helicity
96 m²/s²
Significant tornado parameter
0.8
Supercell composite
4.3

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 20, 10:05 PM EDTSevere Thunderstorm WatchSPCDefiance, Fulton, Lucas, Williams5 hr
May 21, 2:40 AM EDTMesoscale DiscussionSPCAshland, Carroll, Columbiana, Coshocton, Crawford, Cuyahoga and 20 more65 min
May 21, 4:45 AM EDTMesoscale DiscussionSPCBelmont, Carroll, Columbiana, Coshocton, Fairfield, Franklin and 12 more60 min
May 21, 10:40 AM EDTMesoscale DiscussionSPCAllen, Crawford, Cuyahoga, Defiance, Erie, Fulton and 14 more2 hr
May 21, 1:05 PM EDTSevere Thunderstorm WatchSPCAllen, Ashland, Auglaize, Champaign, Coshocton, Crawford and 32 more4 hr
May 21, 2:19 PM EDTMesoscale DiscussionSPCAshland, Ashtabula, Carroll, Columbiana, Crawford, Cuyahoga and 27 more116 min
May 21, 3:15 PM EDTSevere Thunderstorm WatchSPCAshtabula, Belmont, Carroll, Columbiana, Cuyahoga, Geauga and 10 more6 hr
May 21, 6:35 PM EDTSevere Thunderstorm WatchSPCGallia, Meigs4 hr

Nearby

Severe Thunderstorm Watches in Ohio, 2004Every severe thunderstorm watch in 2004

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.