Alert archive / Texas / Mesoscale Discussions in 2004

Mesoscale Discussion 409

April 21, 20046 counties in Kansas; Beaver County, Cimarron County, Texas County, Oklahoma; 10 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 21, 2004, 1:56 PM CDT for 6 counties in Kansas; Beaver County, Cimarron County, Texas County, Oklahoma; 10 counties in Texas. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued
Apr 21, 2004, 1:56 PM CDT (18:56 UTC)
Expired
Apr 21, 2004, 3:30 PM CDT
In force
94 min
Issued by
the Storm Prediction Center

Counties Grant County, KS, Meade County, KS, Morton County, KS, Seward County, KS, Stanton County, KS, Stevens County, KS, Beaver County, OK, Cimarron County, OK, Texas County, OK, Dallam County, TX, Gray County, TX, Hansford County, TX, Hemphill County, TX, Hutchinson County, TX, Lipscomb County, TX, Moore County, TX, Ochiltree County, TX, Roberts County, TX, Sherman County, TX

The radar

The Amarillo radar (KAMA), 153 km from the middle of the area, began a volume at 18:58 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

Dodge City, (KDDC), launched 12:00Z, 6.9 hours before the alert went out and 195 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, Dodge City, at 12:00Z on 2004-04-21Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Dodge City, at 12:00Z on 2004-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 square meters per square second.1939587897117Sfc1 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
2357 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
206 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

477 
ACUS11 KWNS 211856
SWOMCD
SPC MCD 211856 
TXZ000-OKZ000-KSZ000-COZ000-212030-

MESOSCALE DISCUSSION 0409
NWS STORM PREDICTION CENTER NORMAN OK
0156 PM CDT WED APR 21 2004

AREAS AFFECTED...SERN CO...SWRN KS...OK PANHANDLE...NERN TX
PANHANDLE

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 211856Z - 212030Z

...SEVERE THUNDERSTORMS WILL SOON DEVELOP ACROSS THE SRN HIGH
PLAINS...

EXIT REGION OF UPPER JET APPEARS TO BE AGITATING CU FIELD FROM NWRN
TX PANHANDLE INTO SWRN KS.  VERY COLD MID LEVEL TEMPERATURES WILL
CONTRIBUTE TO STEEP LAPSE RATES AND INCREASING INSTABILITY AS ELY
LOW LEVEL FLOW CONTINUES TO ADVECT MOISTURE WWD.  IT APPEARS
THUNDERSTORMS WILL SOON DEVELOP ACROSS THIS REGION WHERE VERTICAL
SHEAR PROFILES WILL FAVOR SUPERCELL DEVELOPMENT.  TORNADO WATCH WILL
LIKELY BE ISSUED FOR THIS REGION BY 20Z.

..DARROW.. 04/21/2004

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...DDC...AMA...PUB...

37160261 37680162 37410023 36200013 35110034 35800186
36290288

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 20, 7:22 PM CDTMesoscale DiscussionSPCAllen, Bourbon, Butler, Chautauqua, Cherokee, Cowley and 8 more23 min
Apr 21, 3:00 PM CDTSevere Thunderstorm WatchSPCGrant, Hamilton, Haskell, Meade, Morton, Seward and 2 more6 hr
Apr 21, 5:09 PM CDTMesoscale DiscussionSPCGrant, Hamilton, Haskell, Meade, Morton, Seward and 2 more66 min
Apr 20, 7:50 PM CDTTornado WatchSPCAdair, Cherokee, Cleveland, Craig, Creek, Delaware and 13 more5 hr
Apr 20, 8:57 PM CDTMesoscale DiscussionSPCAdair, Cherokee, Cleveland, Craig, Creek, Delaware and 13 more2 hr
Apr 20, 10:39 PM CDTMesoscale DiscussionSPCHaskell, Hughes, Latimer, LeFlore, McIntosh, Muskogee and 6 more3 hr
Apr 20, 10:57 PM CDTMesoscale DiscussionSPCAdair, Cherokee, Cleveland, Craig, Creek, Delaware and 13 more93 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, 4:39 PM CDTMesoscale DiscussionSPCAdair, Alfalfa, Atoka, Beckham, Blaine, Caddo and 47 more66 min
Apr 21, 6:02 PM CDTMesoscale DiscussionSPCAdair, Alfalfa, Atoka, Blaine, Canadian, Cherokee and 43 more88 min
Apr 21, 5:30 PM CDTMesoscale DiscussionSPCCooke, Grayson, Montague60 min

Nearby

Mesoscale Discussions in Texas, 2004Mesoscale Discussions in Kansas, 2004Mesoscale Discussions in Oklahoma, 2004Every mesoscale discussion 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.