Alert archive / Nebraska / Tornado Warnings in 2021

Tornado Warning 2, NWS Cheyenne, WY

May 26, 2021Sioux County, Nebraska

NWS Cheyenne, WY issued this tornado warning at May 26, 2021, 4:47 PM MDT for Sioux County, Nebraska. It was in force for 28 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 26, 2021, 4:47 PM MDT (22:47 UTC)
Expired: May 26, 2021, 5:15 PM MDT
In force: 28 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.0 in

County Sioux County, NE

The radar

The Cheyenne radar (KCYS), 171 km from the middle of the area, began a volume at 22:49 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 26, 5:02 PM MDT	HAIL 1	1 Nnw Agate, NE	HAIL REPORTED FALLING FROM 502 TO 506 PM.

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 26, 1:27 PM MDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Rapid City, SD (KUNR), launched 12:00Z, 10.8 hours before the alert went out and 195 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: 797 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 48 m²/s²
0-3 km storm-relative helicity: 366 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

778 
WFUS55 KCYS 262247
TORCYS
NEC165-262315-
/O.NEW.KCYS.TO.W.0002.210526T2247Z-210526T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Cheyenne WY
447 PM MDT Wed May 26 2021

The National Weather Service in Cheyenne has issued a

* Tornado Warning for...
  Central Sioux County in the Panhandle of Nebraska...

* Until 515 PM MDT.
    
* At 447 PM MDT, a severe thunderstorm capable of producing a tornado
  was located near Agate Bed National Monument, or 25 miles northeast
  of Torrington, moving northeast at 45 mph.

  HAZARD...Tornado and quarter size hail.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  Agate Bed National Monument around 455 PM MDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4230 10354 4220 10387 4236 10398 4260 10359
      4257 10348 4244 10348 4244 10345 4238 10345
TIME...MOT...LOC 2247Z 226DEG 40KT 4233 10382 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Allen

2 follow-up statements

380 
WWUS55 KCYS 262301
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
501 PM MDT Wed May 26 2021

NEC165-262315-
/O.CON.KCYS.TO.W.0002.000000T0000Z-210526T2315Z/
Sioux NE-
501 PM MDT Wed May 26 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 515 PM MDT FOR CENTRAL
SIOUX COUNTY...
    
At 500 PM MDT, a severe thunderstorm capable of producing a tornado
was located near Agate Bed National Monument, or 32 miles northeast
of Torrington, moving east at 40 mph.

HAZARD...Tornado and quarter size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornadic thunderstorm will remain over mainly rural areas of
central Sioux County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4230 10354 4224 10375 4242 10386 4260 10359
      4257 10348 4244 10348 4244 10345 4238 10345
TIME...MOT...LOC 2300Z 252DEG 33KT 4234 10368 

TORNADO...RADAR INDICATED
HAIL...1.00IN

$$

Allen

916 
WWUS55 KCYS 262309
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
509 PM MDT Wed May 26 2021

NEC165-262319-
/O.EXP.KCYS.TO.W.0002.000000T0000Z-210526T2315Z/
Sioux NE-
509 PM MDT Wed May 26 2021

...THE TORNADO WARNING FOR CENTRAL SIOUX COUNTY WILL EXPIRE AT 515 PM
MDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.  However small hail
and gusty winds are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
the Panhandle of Nebraska.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Cheyenne.

LAT...LON 4230 10354 4224 10375 4242 10386 4260 10359
      4257 10348 4244 10348 4244 10345 4238 10345
TIME...MOT...LOC 2309Z 226DEG 40KT 4239 10361 

$$

Allen

The office that day

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

Issued	Product	Office	Counties	Lasted
May 26, 2:25 PM MDT	Special Weather Statement	CYS	Dawes	50 min
May 26, 2:50 PM MDT	Special Weather Statement	CYS	Sioux	40 min
May 26, 3:08 PM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Dawes, Sioux	37 min
May 26, 3:17 PM MDT	Special Weather Statement	CYS	Dawes	43 min
May 26, 3:20 PM MDT	Severe Thunderstorm Warning	CYS	Dawes	40 min
May 26, 3:45 PM MDT	Severe Thunderstorm Warning	CYS	Dawes	45 min
May 26, 4:15 PM MDT	Special Weather Statement	CYS	Sioux	45 min
May 26, 4:29 PM MDT	Special Weather Statement	CYS	Dawes	46 min
May 26, 4:36 PM MDT	Special Weather Statement	CYS	Cheyenne, Kimball	39 min
May 26, 4:39 PM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Dawes	51 min
May 26, 5:18 PM MDT	Special Weather Statement	CYS	Morrill	42 min
May 26, 5:27 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne, Morrill	33 min
May 26, 5:30 PM MDT	Severe Thunderstorm Warning	CYS	Banner	34 min
May 26, 5:32 PM MDT	Special Weather Statement	CYS	Box Butte	43 min
May 26, 5:41 PM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Sioux	34 min
May 26, 5:42 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne	30 min

Nearby

Tornado Warnings in Nebraska, 2021 Every tornado warning in 2021 Tornadoes 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.