Alert archive / Wyoming / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 1, NWS Cheyenne, WY

April 25, 2024Converse County, Niobrara County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Apr 25, 2024, 12:35 PM MDT for Converse County, Niobrara County, Wyoming. It was in force for 26 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: Apr 25, 2024, 12:35 PM MDT (18:35 UTC)
Expired: Apr 25, 2024, 1:01 PM MDT
In force: 26 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 18:39 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

Rapid City, SD (KUNR), launched 12:00Z, 6.6 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-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: 26 J/kg
Mixed-layer CIN: -232 J/kg
Mixed-layer LCL: 1805 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: 34 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 Apr 25, 11:46 AM MDT, 49 minutes earlier.

Area forecast discussion, Apr 25, 11:46 AM MDT, 49 minutes before

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In the hours before

Special weather statement, Apr 25, 11:56 AM MDT, 39 minutes before

Special Weather Statement
National Weather Service Cheyenne WY
1156 AM MDT Thu Apr 25 2024

WYZ101-103-251830-
Converse County Lower Elevations WY-North Laramie Range WY-
1156 AM MDT Thu Apr 25 2024

...A STRONG THUNDERSTORM WILL IMPACT SOUTH CENTRAL CONVERSE COUNTY
THROUGH 1230 PM MDT...

At 1155 AM MDT, Doppler radar was tracking a strong thunderstorm near
Douglas, moving northeast at 15 mph.

HAZARD...Wind gusts up to 50 mph and half inch hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Douglas.

This includes Interstate 25 in Wyoming between mile markers 127 and
146.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4260 10556 4272 10561 4288 10537 4267 10517
      4254 10543
TIME...MOT...LOC 1755Z 240DEG 14KT 4268 10548

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

Brothers

Special weather statement, Apr 25, 12:24 PM MDT, 11 minutes before

Special Weather Statement
National Weather Service Cheyenne WY
1224 PM MDT Thu Apr 25 2024

WYZ101-251900-
Converse County Lower Elevations WY-
1224 PM MDT Thu Apr 25 2024

...A STRONG THUNDERSTORM WILL IMPACT EAST CENTRAL CONVERSE COUNTY
THROUGH 100 PM MDT...

At 1223 PM MDT, Doppler radar was tracking a strong thunderstorm 10
miles southeast 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 hail damage to vegetation is
         possible.

Locations impacted include...
Lost Springs.

This includes Interstate 25 in Wyoming between mile markers 121 and
134.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4261 10531 4272 10536 4285 10491 4261 10490
TIME...MOT...LOC 1823Z 251DEG 17KT 4266 10522

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

Brothers

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 25, 11:56 AM MDT	Special Weather Statement	CYS	Converse	34 min
Apr 25, 12:24 PM MDT	Special Weather Statement	CYS	Converse	36 min
Apr 25, 3:11 PM MDT	Tornado Warning	CYS	Goshen	34 min
Apr 25, 3:45 PM MDT	Special Weather Statement	CYS	Goshen	30 min
Apr 25, 4:16 PM MDT	Special Weather Statement	CYS	Goshen	29 min
Apr 25, 4:53 PM MDT	Special Weather Statement	CYS	Niobrara	37 min
Apr 25, 5:47 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	23 min
Apr 24, 9:03 PM MDT	Special Weather Statement	CYS	Kimball	42 min
Apr 25, 3:09 PM MDT	Special Weather Statement	CYS	Scotts Bluff	36 min
Apr 25, 5:14 PM MDT	Special Weather Statement	CYS	Scotts Bluff	46 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2024 Every severe thunderstorm warning in 2024

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.