Alert archive / Wyoming / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 171, NWS Cheyenne, WY

June 28, 2023Converse County, Niobrara County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jun 28, 2023, 2:22 PM MDT for Converse County, Niobrara County, Wyoming. It was in force for 53 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 28, 2023, 2:22 PM MDT (20:22 UTC)
Expired
Jun 28, 2023, 3:15 PM MDT
In force
53 min
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Converse County, WY, Niobrara County, WY

The radar

The Cheyenne radar (KCYS), 208 km from the middle of the area, began a volume at 20:21 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 watch it was issued in

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

IssuedProductOfficeLasted
Jun 28, 1:56 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Rapid City, SD (KUNR), launched 12:00Z, 8.4 hours before the alert went out and 207 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 12:00Z on 2023-06-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLLFCEL10008507005003002001001 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 12:00Z on 2023-06-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -54 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
1886 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
-54 m²/s²
0-3 km storm-relative helicity
11 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Cheyenne, WY wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 28, 11:32 AM MDT, 2 hours 50 minutes earlier.

Area forecast discussion, Jun 28, 11:32 AM MDT, 2 hours 50 minutes before
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Hazardous weather outlook, Jun 28, 3:44 AM MDT, 10 hours 38 minutes before
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In the hours before

Special weather statement, Jun 28, 1:48 PM MDT, 34 minutes before
Special Weather Statement
National Weather Service Cheyenne WY
148 PM MDT Wed Jun 28 2023

WYZ101-282030-
Converse County Lower Elevations WY-
148 PM MDT Wed Jun 28 2023

...A strong thunderstorm will impact portions of east central
Converse County through 230 PM MDT...

At 147 PM MDT, Doppler radar was tracking a strong thunderstorm over
Douglas, moving east at 15 mph.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

This storm will remain over mainly rural areas of east central
Converse County.

This includes Interstate 25 in Wyoming between mile markers 125 and
141.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4269 10545 4274 10548 4292 10522 4262 10507
TIME...MOT...LOC 1947Z 251DEG 15KT 4272 10541

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Rubin
Special weather statement, Jun 28, 2:06 PM MDT, 16 minutes before
Special Weather Statement
National Weather Service Cheyenne WY
206 PM MDT Wed Jun 28 2023

WYZ101-102-282045-
Converse County Lower Elevations WY-Niobrara County WY-
206 PM MDT Wed Jun 28 2023

...A strong thunderstorm will impact portions of southwestern
Niobrara and east central Converse Counties through 245 PM MDT...

At 205 PM MDT, Doppler radar was tracking a strong thunderstorm 14
miles north of Glendo, or 17 miles east of Douglas, moving east at 20
mph.

HAZARD...Wind gusts up to 50 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

This storm will remain over mainly rural areas of southwestern
Niobrara and east central Converse Counties, including the following
locations... Lost Springs.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
east central Wyoming.

&&

LAT...LON 4264 10513 4278 10519 4296 10485 4262 10472
TIME...MOT...LOC 2005Z 250DEG 16KT 4271 10505

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

Rubin

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 28, 1:21 PM MDTFlood WatchCYSConverse, Goshen, Laramie, Niobrara, Platte55 hr
Jun 28, 1:48 PM MDTSpecial Weather StatementCYSConverse42 min
Jun 28, 2:06 PM MDTSpecial Weather StatementCYSNiobrara39 min
Jun 28, 2:43 PM MDTSpecial Weather StatementCYSLaramie47 min
Jun 28, 2:45 PM MDTSpecial Weather StatementCYSConverse45 min
Jun 28, 3:13 PM MDTSevere Thunderstorm WarningCYSConverse, Goshen, Niobrara, Platte62 min
Jun 28, 3:26 PM MDTSpecial Weather StatementCYSPlatte34 min
Jun 28, 3:29 PM MDTSpecial Weather StatementCYSConverse46 min
Jun 28, 3:47 PM MDTSpecial Weather StatementCYSConverse43 min
Jun 28, 3:55 PM MDTSpecial Weather StatementCYSLaramie35 min
Jun 28, 3:59 PM MDTSevere Thunderstorm WarningCYSGoshen, Laramie46 min
Jun 28, 4:07 PM MDTSevere Thunderstorm WarningCYSPlatte38 min
Jun 28, 4:12 PM MDTSevere Thunderstorm WarningCYSGoshen, Niobrara63 min
Jun 28, 4:20 PM MDTSevere Thunderstorm WarningCYSGoshen, Laramie25 min
Jun 28, 4:21 PM MDTSpecial Weather StatementCYSPlatte39 min
Jun 28, 4:39 PM MDTSevere Thunderstorm Warning Destructive damage threatCYSGoshen, Laramie66 min
Jun 28, 4:49 PM MDTSpecial Weather StatementCYSConverse41 min
Jun 28, 5:18 PM MDTSevere Thunderstorm Warning Considerable damage threatCYSLaramie57 min
Jun 28, 5:52 PM MDTSevere Thunderstorm WarningCYSLaramie42 min
Jun 28, 5:12 PM MDTSevere Thunderstorm WarningCYSBox Butte, Dawes, Sioux63 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2023Every severe thunderstorm warning in 2023

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.