Alert archive / Nebraska / Tornado Warnings in 2001

Tornado Warning 71, NWS Sioux Falls, SD

August 17, 2001Dakota County, Nebraska; Woodbury County, Iowa

NWS Sioux Falls, SD issued this tornado warning at Aug 17, 2001, 6:30 PM CDT for Dakota County, Nebraska; Woodbury County, Iowa. It was in force for 15 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Aug 17, 2001, 6:30 PM CDT (23:30 UTC)
Expired: Aug 17, 2001, 6:45 PM CDT
In force: 15 min
Issued by: NWS Sioux Falls, SD
Area: Whole counties; the outline is the Mesonet’s reconstruction

Counties Woodbury County, IA, Dakota County, NE

The watch it was issued in

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

Issued	Product	Office	Lasted
Aug 17, 5:30 PM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.5 hours before the alert went out and 117 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1475 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: -21 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.

886 
WFUS53 KFSD 172331
TORFSD
IAC193-NEC043-172345-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
630 PM CDT FRI AUG 17 2001

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHEAST DAKOTA COUNTY IN NORTHEAST NEBRASKA
  SOUTHWEST WOODBURY COUNTY IN NORTHWEST IOWA

* UNTIL 645 PM CDT

* AT 630 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  TORNADO 7 MILES SOUTHWEST OF SALIX...OR ABOUT 19 MILES SOUTH OF
  SIOUX CITY...MOVING SOUTHEAST AT 30 MPH.

THIS IS AN EXTREMELY DANGEROUS AND LIFE THREATENING SITUATION. TAKE
COVER NOW.

LAT...LON 4243 9633 4242 9651 4229 9644 4228 9634
          4221 9624

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 17, 5:22 PM CDT	Severe Thunderstorm Warning	FSD	Dakota	23 min
Aug 17, 5:28 PM CDT	Tornado Warning	FSD	Dakota	32 min
Aug 17, 5:55 PM CDT	Tornado Warning	FSD	Dakota	35 min
Aug 17, 4:07 PM CDT	Severe Thunderstorm Warning	FSD	Lyon	23 min
Aug 17, 4:27 PM CDT	Severe Thunderstorm Warning	FSD	Lyon, Sioux	33 min
Aug 17, 4:57 PM CDT	Severe Thunderstorm Warning	FSD	Sioux	33 min
Aug 17, 5:04 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee, Plymouth	26 min
Aug 17, 5:15 PM CDT	Tornado Warning	FSD	Sioux	30 min
Aug 17, 5:30 PM CDT	Tornado Warning	FSD	Plymouth	30 min
Aug 17, 5:37 PM CDT	Tornado Warning	FSD	Cherokee	23 min
Aug 17, 5:43 PM CDT	Tornado Warning	FSD	Sioux	32 min
Aug 17, 5:55 PM CDT	Tornado Warning	FSD	Cherokee, Plymouth	50 min
Aug 17, 6:39 PM CDT	Tornado Warning	FSD	Ida, Woodbury	51 min
Aug 17, 6:44 PM CDT	Severe Thunderstorm Warning	FSD	Cherokee, Plymouth	16 min

Nearby

Tornado Warnings in Nebraska, 2001 Tornado Warnings in Iowa, 2001 Every tornado warning in 2001 Tornadoes in 2001

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.