Alert archive / Wyoming / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 101, NWS Cheyenne, WY

August 16, 1997Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Aug 16, 1997, 6:14 PM MDT for Laramie County, Wyoming. It was in force for 46 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
Aug 16, 1997, 6:14 PM MDT (00:14 UTC)
Expired
Aug 16, 1997, 7:00 PM MDT
In force
46 min
Issued by
NWS Cheyenne, WY
Area
Whole counties

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 20 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

TimeReportWhereRemark
Aug 16, 6:20 PM MDTHail 0.75Cheyenne, WY

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

Denver, CO (KDNR), launched 00:00Z, 0.2 hours before the alert went out and 202 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 1997-08-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1611 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 1997-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 11 square meters per square second.1939Sfc1 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
1611 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
1576 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
-15 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.

000 
TTAA00 KCYS 170017 RRA
SVRCYS
WYC021-170100-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM AND FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
614 PM MDT SAT AUG 16 1997

* SEVERE THUNDESTORM AND FLASH FLOOD WARNING FOR
  SOUTHWESTERN AND SOUTH CENTRAL LARAMIE COUNTY IN SOUTHEASTERN
WYOMING

* SEVERE THUNDERSTORM WARNING UNTIL 700 PM MDT
  FLASH FLOOD WARNING UNTIL 700 PM MDT

* SOME LOCATIONS AFFECTED
  CHEYENNE                             BY 612 PM MDT
  ORCHARD VALLEY                       BY 612 PM MDT
  ARCHER ESTATES                       BY 631 PM MDT
  HILLSDALE                            BY 653 PM MDT

* AT 612 PM MDT...A SEVERE THUNDERSTORM WAS INDICATED BY DOPPLER
  RADAR IN THE VICINITY OF CHEYENNE MOVING EAST AT 25 MPH.


 
 
STRONG WINDS WITH THIS STORM MAY CAUSE INJURY OR DAMAGE.  TAKE SHELTER
INSIDE A STURDY BUILDING AWAY FROM ALL DOORS AND WINDOWS.

IF YOU ARE DRIVING AND ENCOUNTER HEAVY RAIN OR HAIL...SLOW DOWN OR
PULL TO THE SIDE OF THE ROAD UNTIL THE STORM PASSES.

PAL

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 16, 6:03 PM MDTSevere Thunderstorm WarningCYSLaramie62 min
Aug 16, 6:14 PM MDTFlash Flood WarningCYSLaramie46 min
Aug 16, 6:51 PM MDTFlash Flood WarningCYSLaramie59 min
Aug 16, 6:51 PM MDTSevere Thunderstorm WarningCYSLaramie59 min
Aug 16, 8:09 PM MDTFlash Flood WarningCYSLaramie56 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.