Alert archive / Nebraska / Tornado Warnings in 1999

Tornado Warning 13, NWS Cheyenne, WY

June 10, 1999Sioux County, Nebraska

NWS Cheyenne, WY issued this tornado warning at Jun 10, 1999, 7:00 PM MDT for Sioux County, Nebraska. It was in force for 15 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Jun 10, 1999, 7:00 PM MDT (01:00 UTC)
Expired
Jun 10, 1999, 7:15 PM MDT
In force
15 min
Issued by
NWS Cheyenne, WY
Area
Whole counties

County Sioux County, NE

The radar

The Cheyenne radar (KCYS), 172 km from the middle of the area, began a volume at 01:00 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.

What was reported inside it

TimeReportWhereRemark
Jun 10, 7:00 PM MDTTornado F0Harrison, NETornado reported 12 miles north of Mitchell, NE

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Rapid City, SD (KUNR), launched 00:00Z, 1.0 hours before the alert went out and 190 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, Rapid City, SD at 00:00Z on 1999-06-11Temperature 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, Rapid City, SD at 00:00Z on 1999-06-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 192 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
884 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
192 m²/s²
0-3 km storm-relative helicity
438 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.

593 
WFUS1 KCYS 110102 RRA
TORCYS
NEC165-110115-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
700 PM MDT THU JUN 10 1999

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHWESTERN SIOUX COUNTY IN THE NEBRASKA PANHANDLE

* UNTIL 715 PM MDT

* AT AT 655 PM MDT... SPOTTERS INDICATED A TORNADO NEAR HENRY IN
  EXTREME SOUTHWEST SIOUX COUNTY NEBRASKA... MOVING NORTHEAST AT 20
  MPH..

* THE TORNADO IS EXPECTED TO STAY OVER OPEN COUNTRY.

NEVER TRY TO OUTRUN A TORNADO IN YOUR VEHICLE  STOP...GET OUT...AND
SEEK SHELTER IN A BASEMENT OR LIE FLAT IN A DITCH AND COVER YOUR HEAD.

PAL

The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 10, 7:29 PM MDTTornado WarningCYSSioux16 min
Jun 10, 7:46 PM MDTTornado WarningCYSSioux29 min
Jun 10, 8:20 PM MDTTornado WarningCYSSioux30 min
Jun 10, 8:25 PM MDTTornado WarningCYSBox Butte30 min

Nearby

Tornado Warnings in Nebraska, 1999Every tornado warning in 1999Tornadoes in 1999

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.