Alert archive / Oklahoma / Tornado Watches in 2004

Tornado Watch 97

April 20, 20045 counties in Arkansas; 4 counties in Missouri; 19 counties in Oklahoma

The Storm Prediction Center issued this tornado watch at Apr 20, 2004, 7:50 PM CDT for 5 counties in Arkansas; 4 counties in Missouri; 19 counties in Oklahoma. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Apr 20, 2004, 7:50 PM CDT (00:50 UTC)
Expired
Apr 21, 2004, 1:00 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center
All 28 counties

Benton County, AR, Carroll County, AR, Crawford County, AR, Madison County, AR, Washington County, AR, Barry County, MO, McDonald County, MO, Stone County, MO, Taney County, MO, Adair County, OK, Cherokee County, OK, Cleveland County, OK, Craig County, OK, Creek County, OK, Delaware County, OK, Haskell County, OK, Mayes County, OK, McIntosh County, OK, Muskogee County, OK, Okfuskee County, OK, Okmulgee County, OK, Ottawa County, OK, Pottawatomie County, OK, Rogers County, OK, Seminole County, OK, Sequoyah County, OK, Tulsa County, OK, Wagoner County, OK

The radar

The Tulsa radar (KINX), 38 km from the middle of the area, began a volume at 00:51 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

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

IssuedProductOfficeCountiesLasted
Apr 20, 7:52 PM CDTSevere Thunderstorm WarningTSARogers23 min
Apr 20, 8:03 PM CDTSevere Thunderstorm WarningTSAOkmulgee57 min
Apr 20, 8:15 PM CDTTornado WarningTSACraig, Ottawa45 min
Apr 20, 8:19 PM CDTSevere Thunderstorm WarningTSAMayes, Rogers41 min
Apr 20, 8:25 PM CDTTornado WarningTSAWagoner50 min
Apr 20, 8:28 PM CDTTornado WarningTSAOkmulgee47 min
Apr 20, 8:43 PM CDTSevere Thunderstorm WarningTSAMayes47 min
Apr 20, 8:44 PM CDTSevere Thunderstorm WarningTSACreek46 min
Apr 20, 8:51 PM CDTSevere Thunderstorm WarningTSAOttawa39 min
Apr 20, 9:02 PM CDTTornado WarningTSAMuskogee43 min
Apr 20, 9:08 PM CDTSevere Thunderstorm WarningTSAOkfuskee37 min
Apr 20, 9:13 PM CDTSevere Thunderstorm WarningTSACherokee, Wagoner47 min
Apr 20, 9:21 PM CDTTornado WarningTSAOkfuskee24 min
Apr 20, 9:29 PM CDTTornado WarningTSAOkmulgee46 min
Apr 20, 9:31 PM CDTSevere Thunderstorm WarningTSACreek44 min
Apr 20, 9:41 PM CDTSevere Thunderstorm WarningTSADelaware49 min
Apr 20, 9:44 PM CDTSevere Thunderstorm WarningTSAMuskogee46 min
Apr 20, 10:22 PM CDTSevere Thunderstorm WarningTSACherokee38 min
Apr 20, 10:24 PM CDTSevere Thunderstorm WarningTSAMcIntosh51 min
Apr 20, 10:52 PM CDTSevere Thunderstorm WarningTSAMcIntosh, Okfuskee, Okmulgee38 min
Apr 20, 11:08 PM CDTSevere Thunderstorm WarningTSAMadison, Washington52 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Springfield, MO (KSGF), launched 00:00Z, 0.8 hours before the alert went out and 185 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, Springfield, MO at 00:00Z on 2004-04-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 40 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, Springfield, MO at 00:00Z on 2004-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 147 square meters per square second.19395878Sfc1 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
40 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
860 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
147 m²/s²
0-3 km storm-relative helicity
176 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

097 
WWUS20 KWNS 210047
SEL7  
SPC WW 210050
ARZ000-MOZ000-OKZ000-210600-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 97
NWS STORM PREDICTION CENTER NORMAN OK
750 PM CDT TUE APR 20 2004

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       NORTHWEST ARKANSAS
       SOUTHWEST CORNER OF MISSOURI
       EASTERN OKLAHOMA

EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 750 PM
UNTIL 100 AM CDT.

TORNADOES...HAIL TO 4 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 80 STATUTE MILES EAST AND WEST
OF A LINE FROM 50 MILES SOUTHWEST OF MUSKOGEE OKLAHOMA TO 5 MILES
EAST NORTHEAST OF MONETT MISSOURI.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 93. WATCH NUMBER 93 WILL NOT BE IN EFFECT AFTER 750
PM CDT. CONTINUE...WW 94...WW 95...WW 96...

DISCUSSION...TORNADIC SUPERCELLS NERN OK EXPECTED TO PERSIST THRU
THE EVENING AS SHEAR PROFILES AND INSTABILITY WILL REMAIN STRONG E
OF DRY LINE.  STORMS WILL LIKELY DEVELOP/MOVE S OF E INTO NWRN AR.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 4 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550.
MEAN STORM MOTION VECTOR 24025.


...HALES

350,0972 365,0951 365,0922 350,0943

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 20, 7:22 PM CDTMesoscale DiscussionSPCBenton, Madison, Washington23 min
Apr 20, 8:57 PM CDTMesoscale DiscussionSPCBenton, Carroll, Crawford, Madison, Washington2 hr
Apr 20, 10:39 PM CDTMesoscale DiscussionSPCCrawford, Franklin, Scott, Sebastian3 hr
Apr 20, 10:57 PM CDTMesoscale DiscussionSPCBenton, Carroll, Crawford, Madison, Washington93 min
Apr 21, 2:13 PM CDTMesoscale DiscussionSPCBaxter, Boone, Clark, Cleburne, Cleveland, Conway and 30 more92 min
Apr 21, 2:40 PM CDTTornado WatchSPCArkansas, Ashley, Baxter, Benton, Boone, Bradley and 52 more6 hr
Apr 21, 4:40 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Baxter, Benton, Boone, Bradley and 52 more95 min
Apr 21, 6:29 PM CDTMesoscale DiscussionSPCArkansas, Baxter, Benton, Boone, Carroll, Chicot and 25 more91 min
Apr 20, 7:20 PM CDTMesoscale DiscussionSPCAdair, Audrain, Bates, Benton, Boone, Caldwell and 38 more115 min
Apr 20, 8:06 PM CDTMesoscale DiscussionSPCAtchison84 min
Apr 20, 9:38 PM CDTMesoscale DiscussionSPCAudrain, Boone, Callaway, Cole, Crawford, Dent and 16 more37 min
Apr 20, 11:10 PM CDTMesoscale DiscussionSPCCrawford, Dent, Franklin, Gasconade, Iron, Jefferson and 9 more2 hr
Apr 21, 2:58 PM CDTMesoscale DiscussionSPCBollinger, Butler, Cape Girardeau, Mississippi, New Madrid, Pemiscot and 4 more92 min
Apr 21, 12:58 PM CDTMesoscale DiscussionSPCAtoka, Beckham, Blaine, Bryan, Caddo, Canadian and 34 more2 hr
Apr 21, 1:50 PM CDTTornado WatchSPCAdair, Alfalfa, Atoka, Beckham, Blaine, Caddo and 55 more7 hr
Apr 21, 1:56 PM CDTMesoscale DiscussionSPCBeaver, Cimarron, Texas94 min
Apr 21, 3:00 PM CDTSevere Thunderstorm WatchSPCBeaver, Cimarron, Texas6 hr
Apr 21, 4:39 PM CDTMesoscale DiscussionSPCAdair, Alfalfa, Atoka, Beckham, Blaine, Caddo and 47 more66 min
Apr 21, 5:09 PM CDTMesoscale DiscussionSPCBeaver, Cimarron, Texas66 min
Apr 21, 6:02 PM CDTMesoscale DiscussionSPCAdair, Alfalfa, Atoka, Blaine, Canadian, Cherokee and 43 more88 min

Nearby

Tornado Watches in Oklahoma, 2004Tornado Watches in Arkansas, 2004Tornado Watches in Missouri, 2004Every tornado 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.