Alert archive / Nebraska / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 57, NWS Cheyenne, WY

June 21, 1997Morrill County, Nebraska

NWS Cheyenne, WY issued this severe thunderstorm warning at Jun 21, 1997, 6:23 PM MDT for Morrill County, Nebraska. It was in force for 32 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jun 21, 1997, 6:23 PM MDT (00:23 UTC)
Expired
Jun 21, 1997, 6:55 PM MDT
In force
32 min
Issued by
NWS Cheyenne, WY
Area
Whole counties

County Morrill County, NE

The radar

The Cheyenne radar (KCYS), 162 km from the middle of the area, began a volume at 00:24 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 nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 0.4 hours before the alert went out and 206 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, Denver, CO at 00:00Z on 1997-06-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 687 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 1997-06-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 51 square meters per square second.193958Sfc1 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
687 J/kg
Mixed-layer CIN
-122 J/kg
Mixed-layer LCL
2509 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
51 m²/s²
0-3 km storm-relative helicity
135 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.2

Open this sounding in Storm Lab

The text

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

673 
WUUS1 KCYS 220023 RRA
SVRCYS
NEC123-220055-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
623 PM MDT SAT JUN 21 1997

* SEVERE THUNDERSTORM WARNING FOR
  NORTHEAST MORRILL COUNTY IN WESTERN NEBRASKA PANHANDLE

* UNTIL 655 PM MDT

* THIS STORM WILL REMAIN OVER AREAS

* AT 620 PM MDT...DOPPLER RADAR IN CHEYENNE SHOWED A SEVERE
  THUNDERSTORM 7 MILES NORTHEAST OF ANGORA...OR 10 MILES SOUTHEAST OF
  ALLIANCE...MOVING EAST AT 20 MPH.
 
 
IF SEVERE WEATHER IS OBSERVED...CONTACT YOUR LOCAL LAW ENFORCEMENT
AGENCY AND ASK THEM TO RELAY YOUR INFORMATION TO THE NATIONAL
WEATHER SERVICE.

LARGE HAIL IS LIKELY WITH THIS STORM.  SEEK SHELTER INSIDE A STURDY
BUILDING AWAY FROM ALL WINDOWS UNTIL THE STORM PASSES.

SULLIVAN

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 6:40 PM MDTSevere Thunderstorm WarningCYSBox Butte20 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 1997Every severe thunderstorm warning in 1997

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.