Alert archive / Nebraska / Tornado Warnings in 2004

Tornado Warning 9, NWS Omaha, NE

April 20, 2004Antelope County, Nebraska

NWS Omaha, NE issued this tornado warning at Apr 20, 2004, 6:48 PM CDT for Antelope County, Nebraska. It was in force for 12 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Apr 20, 2004, 6:48 PM CDT (23:48 UTC)
Expired
Apr 20, 2004, 7:00 PM CDT
In force
12 min
Issued by
NWS Omaha, NE
Area
Counties, with a storm outline in the text

County Antelope County, NE

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 20, 6:25 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.8 hours before the alert went out and 153 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, Omaha, NE at 12:00Z on 2004-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 13 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, Omaha, NE at 12:00Z on 2004-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 74 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
13 J/kg
Mixed-layer CIN
-209 J/kg
Mixed-layer LCL
546 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
74 m²/s²
0-3 km storm-relative helicity
105 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

The text

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

722 
WFUS53 KOAX 202348
TOROAX
NEC003-210000-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE OMAHA NE
645 PM CDT TUE APR 20 2004

THE NATIONAL WEATHER SERVICE IN OMAHA HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHEASTERN ANTELOPE COUNTY IN NORTHEAST NEBRASKA

* UNTIL 700 PM CDT

* AT 645 PM CDT...RADAR INDICATED A SEVERE STORM WITH A POSSIBLE   
  TORNADO. THE MOST DANGEROUS PART OF THE STORM WAS LOCATED NEAR 
  OAKDALE...OR ABOUT 25 MILES WEST OF NORFOLK...MOVING EAST AT 35 
  MPH. GOLFBALL SIZE HAIL WAS REPORTED AT 645 PM AT OAKDALE ALONG 
  WITH 60 MPH WINDS.

* THE TORNADO IS EXPECTED TO BE NEAR...
RURAL SOUTHEASTERN ANTELOPE COUNTY AROUND 655 PM CDT

IF YOU ARE IN THE PATH OF A TORNADO...GET TO A BASEMENT IF ONE IS 
AVAILABLE. OTHERWISE GO TO A SMALL INTERIOR ROOM SUCH AS A CLOSET.

LAT...LON 4206 9808 4199 9798 4192 9790 4192 9784
          4209 9784 4209 9790 4209 9802

$$

DEWALD

The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 20, 5:54 PM CDTSevere Thunderstorm WarningOAXAntelope66 min
Apr 20, 6:10 PM CDTTornado WarningOAXAntelope35 min
Apr 20, 6:43 PM CDTTornado WarningOAXMadison47 min

Nearby

Tornado Warnings in Nebraska, 2004Every tornado warning in 2004Tornadoes 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.