Alert archive / Nebraska / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 124, NWS Cheyenne, WY

August 14, 20214 counties in Nebraska

NWS Cheyenne, WY issued this severe thunderstorm warning at Aug 14, 2021, 5:52 PM MDT for 4 counties in Nebraska. It was in force for 38 min. 6 reports 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: Aug 14, 2021, 5:52 PM MDT (23:52 UTC)
Expired: Aug 14, 2021, 6:30 PM MDT
In force: 38 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Tornado: Possible
Damage threat: Destructive
Hail: 2.75 in
Wind: 60.0 mph

Counties Box Butte County, NE, Morrill County, NE, Scotts Bluff County, NE, Sioux County, NE

The radar

The Cheyenne radar (KCYS), 155 km from the middle of the area, began a volume at 23:53 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
Aug 14, 6:06 PM MDT	HAIL 1.75	3 Sw Kilpatrick Lake, NE
Aug 14, 6:10 PM MDT	HAIL 2.5	6 Ssw Kilpatrick Lake, NE
Aug 14, 6:15 PM MDT	HAIL 2.5	14 Nw Angora, NE
Aug 14, 6:31 PM MDT	HAIL 2	15 Nne Bayard, NE
Aug 14, 6:38 PM MDT	HAIL 2.5	8 Nne Moomaws Corner, NE
Aug 14, 6:38 PM MDT	HAIL 3	8 Nne Moomaws Corner, 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
Aug 14, 3:28 PM MDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 11.9 hours before the alert went out and 234 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: 157 J/kg
Mixed-layer CIN: -337 J/kg
Mixed-layer LCL: 1928 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: -20 m²/s²
0-3 km storm-relative helicity: 120 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

775 
WUUS55 KCYS 142352
SVRCYS
NEC013-123-157-165-150030-
/O.NEW.KCYS.SV.W.0124.210814T2352Z-210815T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
Severe Thunderstorm Warning
National Weather Service Cheyenne WY
552 PM MDT Sat Aug 14 2021

The National Weather Service in Cheyenne has issued a

* Severe Thunderstorm Warning for...
  Southwestern Box Butte County in the Panhandle of Nebraska...
  Northeastern Scotts Bluff County in the Panhandle of Nebraska...
  Northwestern Morrill County in the Panhandle of Nebraska...
  Southeastern Sioux County in the Panhandle of Nebraska...

* Until 630 PM MDT.

* At 550 PM MDT, a severe thunderstorm was located over Kilpatrick
  Lake, or 21 miles west of Alliance, moving south at 25 mph.

  THIS IS A DESTRUCTIVE STORM FOR SOUTH BOX BUTTE AND NORTH SCOTTS 
BLUFF COUNTIES!

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

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be severely injured. 
           Expect shattered windows, extensive damage to roofs, 
           siding, and vehicles.

* Locations impacted include...
  Angora and Kilpatrick Lake. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4186 10346 4215 10339 4217 10324 4184 10297
TIME...MOT...LOC 2350Z 351DEG 20KT 4208 10329 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...DESTRUCTIVE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...2.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Claycomb

2 follow-up statements

407 
WWUS55 KCYS 142356
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
556 PM MDT Sat Aug 14 2021

NEC013-123-157-165-150030-
/O.CON.KCYS.SV.W.0124.000000T0000Z-210815T0030Z/
Box Butte NE-Scotts Bluff NE-Morrill NE-Sioux NE-
556 PM MDT Sat Aug 14 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM MDT
FOR SOUTHWESTERN BOX BUTTE...NORTHEASTERN SCOTTS BLUFF...NORTHWESTERN
MORRILL AND SOUTHEASTERN SIOUX COUNTIES...

At 555 PM MDT, a severe thunderstorm was located over Kilpatrick
Lake, or 21 miles west of Alliance, moving south at 25 mph.

THIS IS A DESTRUCTIVE STORM FOR SOUTHERN BOX BUTTE AND NORTHERN 
MORRILL COUNTIES!

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

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be severely injured. 
         Expect shattered windows, extensive damage to roofs, 
         siding, and vehicles.

Locations impacted include...
Angora and Kilpatrick Lake. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Cheyenne.

&&

LAT...LON 4186 10346 4212 10339 4216 10324 4184 10297
TIME...MOT...LOC 2355Z 351DEG 20KT 4205 10328 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...DESTRUCTIVE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...2.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Claycomb

128 
WWUS55 KCYS 150014
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
614 PM MDT Sat Aug 14 2021

NEC165-150022-
/O.CAN.KCYS.SV.W.0124.000000T0000Z-210815T0030Z/
Sioux NE-
614 PM MDT Sat Aug 14 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SIOUX COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 1100 PM MDT for
the Panhandle of Nebraska.

LAT...LON 4187 10339 4207 10336 4208 10317 4184 10297
TIME...MOT...LOC 0012Z 351DEG 18KT 4198 10327 

$$

NEC013-123-157-150030-
/O.CON.KCYS.SV.W.0124.000000T0000Z-210815T0030Z/
Box Butte NE-Scotts Bluff NE-Morrill NE-
614 PM MDT Sat Aug 14 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM MDT
FOR SOUTHWESTERN BOX BUTTE...EAST CENTRAL SCOTTS BLUFF AND
NORTHWESTERN MORRILL COUNTIES...

At 612 PM MDT, a severe thunderstorm was located 7 miles south of
Kilpatrick Lake, or 21 miles east of Scottsbluff, moving south at 20
mph.

THIS IS A DESTRUCTIVE STORM FOR SOUTHERN BOX BUTTE AND NORTHERN 
MORRILL COUNTIES!

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

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be severely injured. 
         Expect shattered windows, extensive damage to roofs, 
         siding, and vehicles.

Locations impacted include...
Angora.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Cheyenne.

&&

LAT...LON 4187 10339 4207 10336 4208 10317 4184 10297
TIME...MOT...LOC 0012Z 351DEG 18KT 4198 10327 

TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...DESTRUCTIVE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...2.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Claycomb

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 14, 3:54 PM MDT	Severe Thunderstorm Warning	CYS	Dawes	51 min
Aug 14, 4:06 PM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Dawes, Sioux	39 min
Aug 14, 4:14 PM MDT	Severe Thunderstorm Warning Considerable damage threat	CYS	Dawes	46 min
Aug 14, 4:45 PM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Dawes	45 min
Aug 14, 4:50 PM MDT	Severe Thunderstorm Warning Considerable damage threat	CYS	Box Butte, Dawes, Sioux	40 min
Aug 14, 5:22 PM MDT	Severe Thunderstorm Warning Considerable damage threat	CYS	Box Butte, Morrill, Scotts Bluff, Sioux	38 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 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.