Alert archive / Nebraska / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 13, NWS Cheyenne, WY

May 23, 2021Goshen County, Wyoming; Scotts Bluff County, Sioux County, Nebraska

NWS Cheyenne, WY issued this severe thunderstorm warning at May 23, 2021, 2:38 PM MDT for Goshen County, Wyoming; Scotts Bluff County, Sioux County, Nebraska. It was in force for 24 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: May 23, 2021, 2:38 PM MDT (20:38 UTC)
Expired: May 23, 2021, 3:02 PM MDT
In force: 24 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Scotts Bluff County, NE, Sioux County, NE, Goshen County, WY

The radar

The Cheyenne radar (KCYS), 123 km from the middle of the area, began a volume at 20:41 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 23, 2:51 PM MDT	HAIL 1	6 N Morrill, NE

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

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 23, 12:06 PM MDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Rapid City, SD (KUNR), launched 12:00Z, 8.6 hours before the alert went out and 240 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 549 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 271 m²/s²
0-3 km storm-relative helicity: 339 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

712 
WUUS55 KCYS 232038
SVRCYS
NEC157-165-WYC015-232130-
/O.NEW.KCYS.SV.W.0013.210523T2038Z-210523T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Cheyenne WY
238 PM MDT Sun May 23 2021

The National Weather Service in Cheyenne has issued a

* Severe Thunderstorm Warning for...
  Northwestern Scotts Bluff County in the Panhandle of Nebraska...
  Southwestern Sioux County in the Panhandle of Nebraska...
  East central Goshen County in southeastern Wyoming...

* Until 330 PM MDT.

* At 238 PM MDT, a severe thunderstorm was located over Huntley, or 9
  miles southeast of Torrington, moving north at 50 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Torrington, Morrill, Lyman, Huntley, Stegall, Agate Bed National
  Monument and Henry.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 800 PM MDT for the Panhandle
of Nebraska...and southeastern Wyoming.

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4182 10393 4187 10424 4241 10408 4241 10369
TIME...MOT...LOC 2038Z 198DEG 44KT 4194 10409 

HAIL...1.00IN
WIND...60MPH
 
$$

Cox

2 follow-up statements

920 
WWUS55 KCYS 232053
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
253 PM MDT Sun May 23 2021

NEC157-165-WYC015-232130-
/O.CON.KCYS.SV.W.0013.000000T0000Z-210523T2130Z/
Scotts Bluff NE-Sioux NE-Goshen WY-
253 PM MDT Sun May 23 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM MDT
FOR NORTHWESTERN SCOTTS BLUFF...SOUTHWESTERN SIOUX AND EAST CENTRAL
GOSHEN COUNTIES...

At 252 PM MDT, a severe thunderstorm was located 9 miles east of
Torrington, moving north at 50 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Trained weather spotters reported quarter size hail in 
         Torrington.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Torrington, Morrill, Lyman, Huntley, Stegall, Agate Bed National
Monument and Henry.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 800 PM MDT for the Panhandle
of Nebraska...and southeastern Wyoming.

This storm is producing large hail. SEEK SHELTER NOW inside a sturdy
structure and stay away from windows.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4182 10393 4187 10424 4241 10408 4241 10369
TIME...MOT...LOC 2052Z 198DEG 44KT 4211 10402 

HAIL...1.00IN
WIND...60MPH
 
$$

Cox

053 
WWUS55 KCYS 232102
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
302 PM MDT Sun May 23 2021

NEC157-165-WYC015-232112-
/O.CAN.KCYS.SV.W.0013.000000T0000Z-210523T2130Z/
Scotts Bluff NE-Sioux NE-Goshen WY-
302 PM MDT Sun May 23 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN SCOTTS BLUFF...
SOUTHWESTERN SIOUX AND EAST CENTRAL GOSHEN COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.  However heavy rain is
still possible with this thunderstorm.

A Tornado Watch remains in effect until 800 PM MDT for the Panhandle
of Nebraska...and southeastern Wyoming.

LAT...LON 4182 10393 4187 10424 4241 10408 4241 10369
TIME...MOT...LOC 2059Z 198DEG 44KT 4223 10397 

$$

Cox

The office that day

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

Issued	Product	Office	Counties	Lasted
May 23, 12:54 AM MDT	Dense Fog Advisory	CYS	Albany, Laramie	7 hr
May 23, 2:04 AM MDT	High Wind Warning	CYS	Albany, Carbon	18 hr
May 23, 1:18 PM MDT	Special Weather Statement	CYS	Laramie	42 min
May 23, 1:28 PM MDT	Special Weather Statement	CYS	Platte	47 min
May 23, 1:35 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Platte	29 min
May 23, 1:59 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Niobrara, Platte	19 min
May 23, 2:03 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie	42 min
May 23, 3:22 PM MDT	Areal Flood Advisory	CYS	Laramie	3 hr
May 23, 3:45 PM MDT	Special Weather Statement	CYS	Dawes	45 min
May 23, 3:53 PM MDT	Special Weather Statement	CYS	Morrill	52 min
May 23, 4:22 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne	38 min
May 23, 4:31 PM MDT	Tornado Warning Considerable damage threat	CYS	Cheyenne	44 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 2021 Severe Thunderstorm Warnings in Wyoming, 2021 Every severe thunderstorm warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.