Alert archive / Texas / Severe Thunderstorm Watches in 2004

Severe Thunderstorm Watch 849

September 30, 20048 counties in New Mexico; 27 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Sep 30, 2004, 12:55 PM MDT for 8 counties in New Mexico; 27 counties in Texas. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Sep 30, 2004, 12:55 PM MDT (18:55 UTC)
Expired
Sep 30, 2004, 7:00 PM MDT
In force
6 hr
Issued by
the Storm Prediction Center
All 35 counties

Chaves County, NM, Curry County, NM, De Baca County, NM, Eddy County, NM, Guadalupe County, NM, Lea County, NM, Quay County, NM, Roosevelt County, NM, Andrews County, TX, Armstrong County, TX, Bailey County, TX, Borden County, TX, Carson County, TX, Castro County, TX, Cochran County, TX, Crosby County, TX, Dawson County, TX, Deaf Smith County, TX, Floyd County, TX, Gaines County, TX, Garza County, TX, Hale County, TX, Hockley County, TX, Howard County, TX, Lamb County, TX, Lubbock County, TX, Lynn County, TX, Martin County, TX, Oldham County, TX, Parmer County, TX, Potter County, TX, Randall County, TX, Swisher County, TX, Terry County, TX, Yoakum County, TX

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Sep 30, 2:58 PM MDTSevere Thunderstorm WarningMAFEddy62 min
Sep 30, 5:00 PM MDTFlash Flood WarningMAFEddy6 hr
Sep 30, 5:04 PM MDTSevere Thunderstorm WarningLUBGarza41 min
Sep 30, 5:35 PM MDTSevere Thunderstorm WarningLUBTerry40 min
Sep 30, 5:45 PM MDTSevere Thunderstorm WarningLUBGarza45 min
Sep 30, 6:07 PM MDTFlash Flood WarningLUBTerry113 min
Sep 30, 6:56 PM MDTSevere Thunderstorm WarningLUBGarza64 min
Sep 30, 6:56 PM MDTSevere Thunderstorm WarningMAFAndrews64 min
Sep 30, 6:57 PM MDTFlash Flood WarningLUBGarza2 hr
Sep 30, 7:00 PM MDTFlash Flood WarningLUBLynn2 hr
Sep 30, 7:00 PM MDTSevere Thunderstorm WarningLUBLynn60 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

Amarillo Airport, TX (KAMA), launched 12:00Z, 6.9 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.

Skew-T log-pSkew-T log-p diagram, Amarillo Airport, TX at 12:00Z on 2004-09-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 19 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, Amarillo Airport, TX at 12:00Z on 2004-09-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 79 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
19 J/kg
Mixed-layer CIN
-110 J/kg
Mixed-layer LCL
1054 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
85 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.

000 
WWUS20 KWNS 301856
SEL9  
SPC WW 301855
NMZ000-TXZ000-010100-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 849
NWS STORM PREDICTION CENTER NORMAN OK
155 PM CDT THU SEP 30 2004

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

       EASTERN NEW MEXICO
       WEST TEXAS

EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 155 PM UNTIL
800 PM CDT.

HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 120 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 40 MILES NORTH NORTHWEST OF ROSWELL
NEW MEXICO TO 30 MILES EAST SOUTHEAST OF PLAINVIEW TEXAS.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES.

DISCUSSION...SCATTERED THUNDERSTORMS ARE EXPECTED TO INTENSIFY OVER
EASTERN NM THIS AFTERNOON AND SPREAD EASTWARD INTO WEST TX.  COLD
TEMPERATURES ALOFT AND STEEP LAPSE RATES...MLCAPE VALUES OVER 1000
J/KG...AND SUFFICIENT DEEP LAYER VERTICAL SHEAR WILL POSE A RISK OF
SUPERCELLS CAPABLE OF LARGE HAIL.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 26030.


...HART

353,1044 354,1011 321,1011 320,1044

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 30, 12:23 PM MDTMesoscale DiscussionSPCChaves, Curry, Eddy, Lea, Quay, Roosevelt2 hr
Sep 30, 3:52 PM MDTMesoscale DiscussionSPCChildress, Collingsworth, Cottle, Dickens, Donley, Fisher and 18 more83 min
Sep 30, 4:56 PM MDTMesoscale DiscussionSPCJeff Davis, Loving, Pecos, Reeves, Ward, Winkler94 min

Nearby

Severe Thunderstorm Watches in Texas, 2004Severe Thunderstorm Watches in New Mexico, 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.