Alert archive / Nebraska / Tornado Warnings in 1998

Tornado Warning 11, NWS North Platte, NE

May 21, 1998Perkins County, Nebraska

NWS North Platte, NE issued this tornado warning at May 21, 1998, 6:13 PM MDT for Perkins County, Nebraska. It was in force for 32 min. 2 reports 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: May 21, 1998, 6:13 PM MDT (00:13 UTC)
Expired: May 21, 1998, 6:45 PM MDT
In force: 32 min
Issued by: NWS North Platte, NE
Area: Whole counties

County Perkins County, NE

The radar

The North Platte radar (KLNX), 152 km from the middle of the area, began a volume at 00:17 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

Time	Report	Where	Remark
May 21, 6:30 PM MDT	Hail 1.25	Venango, NE
May 21, 6:45 PM MDT	Tornado F0	Grant, NE	A tornado touched down briefly in open country and did little if any damage 11 miles southwest of the community of Grant.

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 watch it was issued in

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

Issued	Product	Office	Lasted
May 21, 2:15 PM MDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 0.2 hours before the alert went out and 93 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: 685 J/kg
Mixed-layer CIN: -16 J/kg
Mixed-layer LCL: 548 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 34 m²/s²
0-3 km storm-relative helicity: 73 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KLBF 220015 RRA
TORLBF
NEC135-220045-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING...CORRECTION FOR COUNTY
NATIONAL WEATHER SERVICE NORTH PLATTE NE
713 PM CDT (613 PM MDT) THU MAY 21 1998

THE NATIONAL WEATHER SERVICE IN NORTH PLATTE HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHWESTERN PERKINS COUNTY IN SOUTHWESTERN NEBRASKA

* UNTIL 645 PM MDT (745 PM CDT)

* AT 612 PM MDT... NORTH PLATTE DOPPLER RADAR INDICATED A TORNADO
  29 MILES NORTHWEST OF IMPERIAL OR 15 MILES NORTH NORTHWEST OF
  LAMAR MOVING EAST AT 15 MPH.

* THE TORNADO IS EXPECTED TO REMAIN IN RURAL AREAS JUST SOUTH OF
  VENANGO.
THIS IS A DANGEROUS SITUATION! ACT QUICKLY! IT MAY SAVE YOUR LIFE!
MOVE TO A BASEMENT IF POSSIBLE. OTHERWTISE...GO TO A SMALL INTERIOR
ROOM ON THE LOWEST FLOOR.  STAY AWAY FROM WINDOWS AND DOORS.

MTM

The office that day

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

Issued	Product	Office	Counties	Lasted
May 21, 6:01 PM MDT	Tornado Warning	LBF	Frontier	34 min
May 21, 6:19 PM MDT	Severe Thunderstorm Warning	LBF	Lincoln	66 min
May 21, 6:38 PM MDT	Tornado Warning	LBF	Frontier	32 min
May 21, 6:44 PM MDT	Severe Thunderstorm Warning	LBF	Chase, Perkins	66 min
May 21, 6:48 PM MDT	Tornado Warning	LBF	Chase, Perkins	62 min
May 21, 7:29 PM MDT	Tornado Warning	LBF	Hayes	66 min
May 21, 7:59 PM MDT	Tornado Warning	LBF	Hayes	66 min
May 21, 8:08 PM MDT	Severe Thunderstorm Warning	LBF	Perkins	47 min
May 21, 8:26 PM MDT	Tornado Warning	LBF	Frontier	64 min
May 21, 8:59 PM MDT	Tornado Warning	LBF	Frontier	66 min
May 21, 10:13 PM MDT	Severe Thunderstorm Warning	LBF	Chase	62 min
May 21, 10:46 PM MDT	Severe Thunderstorm Warning	LBF	Chase	44 min

Nearby

Tornado Warnings in Nebraska, 1998 Every tornado warning in 1998 Tornadoes in 1998

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.