Alert archive / Nebraska / Tornado Warnings in 2011

Tornado Warning 5, NWS Sioux Falls, SD

April 9, 2011Dakota County, Dixon County, Nebraska

NWS Sioux Falls, SD issued this tornado warning at Apr 9, 2011, 7:57 PM CDT for Dakota County, Dixon County, Nebraska. It was in force for 33 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 9, 2011, 7:57 PM CDT (00:57 UTC)
Expired
Apr 9, 2011, 8:30 PM CDT
In force
33 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon

Counties Dakota County, NE, Dixon County, NE

The radar

The Omaha radar (KOAX), 120 km from the middle of the area, began a volume at 00:59 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 watch it was issued in

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

IssuedProductOfficeLasted
Apr 9, 5:48 PM CDTTornado WatchSPC7 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 1.0 hours before the alert went out and 120 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 00:00Z on 2011-04-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3327 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 2011-04-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 270 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
3327 J/kg
Mixed-layer CIN
-24 J/kg
Mixed-layer LCL
1533 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
270 m²/s²
0-3 km storm-relative helicity
403 m²/s²
Significant tornado parameter
3.7
Supercell composite
19.0

Open this sounding in Storm Lab

The text

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

752 
WFUS53 KFSD 100057
TORFSD
NEC043-051-100130-
/O.NEW.KFSD.TO.W.0005.110410T0057Z-110410T0130Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
757 PM CDT SAT APR 9 2011

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  DAKOTA COUNTY IN NORTHEAST NEBRASKA...
  SOUTHEASTERN DIXON COUNTY IN NORTHEAST NEBRASKA...

* UNTIL 830 PM CDT

* AT 757 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE
  TRACKING A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS
  DANGEROUS STORM WAS LOCATED NEAR WAKEFIELD...OR 21 MILES SOUTH OF
  PONCA...AND MOVING NORTHEAST AT 40 MPH.

* THIS TORNADIC STORM WILL BE NEAR...
  HUBBARD AND HOMER AROUND 815 PM CDT...
  JACKSON AROUND 825 PM CDT...

OTHER LOCATIONS IMPACTED BY THIS TORNADIC THUNDERSTORM INCLUDE
WATERBURY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4234 9694 4257 9666 4255 9663 4252 9663
      4251 9658 4237 9641 4235 9642 4234 9641
      4227 9661 4227 9672 4225 9673 4225 9681
TIME...MOT...LOC 0057Z 226DEG 35KT 4229 9682

$$

LIEBL
2 follow-up statements
155 
WWUS53 KFSD 100113
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
813 PM CDT SAT APR 9 2011

NEC043-051-100130-
/O.CON.KFSD.TO.W.0005.000000T0000Z-110410T0130Z/
DAKOTA NE-DIXON NE-
813 PM CDT SAT APR 9 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR SOUTHEASTERN DIXON AND
DAKOTA COUNTIES UNTIL 830 PM CDT...

AT 814 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED 5 MILES SOUTHWEST OF HUBBARD...OR 15 MILES SOUTH OF
PONCA...MOVING NORTHEAST AT 30 MPH.

THIS DANGEROUS STORM WILL BE NEAR...
  HUBBARD AROUND 820 PM CDT...
  JACKSON AND HOMER AROUND 825 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4234 9694 4257 9666 4255 9663 4252 9663
      4251 9658 4237 9641 4235 9642 4234 9641
      4227 9661 4227 9672 4225 9673 4225 9681
TIME...MOT...LOC 0114Z 242DEG 28KT 4237 9663

$$

LIEBL
510 
WWUS53 KFSD 100131 RRA
SVSFSD

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
831 PM CDT SAT APR 9 2011

NEC043-051-100141-
/O.EXP.KFSD.TO.W.0005.000000T0000Z-110410T0130Z/
DAKOTA NE-DIXON NE-
831 PM CDT SAT APR 9 2011

...THE TORNADO WARNING FOR SOUTHEASTERN DIXON AND DAKOTA COUNTIES HAS
EXPIRED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA...HOWEVER SMALL HAIL AND GUSTY WINDS ARE STILL POSSIBLE WITH
THIS THUNDERSTORM.

IN ADDITION...STRONG THUNDERSTORMS MAY REDEVELOP...AND A TORNADO 
WATCH REMAINS IN EFFECT.

LAT...LON 4234 9694 4257 9666 4255 9663 4252 9663
      4251 9658 4237 9641 4235 9642 4234 9641
      4227 9661 4227 9672 4225 9673 4225 9681
TIME...MOT...LOC 0113Z 242DEG 28KT 4237 9664

$$

LIEBL

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 9, 7:29 PM CDTSevere Thunderstorm WarningFSDDixon31 min
Apr 9, 8:19 PM CDTSevere Thunderstorm WarningFSDDakota41 min
Apr 9, 8:34 PM CDTSevere Thunderstorm WarningFSDDakota, Dixon26 min
Apr 9, 8:55 PM CDTSevere Thunderstorm WarningFSDDakota35 min
Apr 9, 9:17 PM CDTSevere Thunderstorm WarningFSDDakota43 min
Apr 9, 9:31 PM CDTTornado WarningFSDDakota29 min

Nearby

Tornado Warnings in Nebraska, 2011Every tornado warning in 2011Tornadoes in 2011

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.