Alert archive / Nebraska / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 119, NWS Cheyenne, WY

August 14, 2021Box Butte County, Dawes County, Sioux County, Nebraska

NWS Cheyenne, WY issued this severe thunderstorm warning at Aug 14, 2021, 4:06 PM MDT for Box Butte County, Dawes County, Sioux County, Nebraska. It was in force for 39 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
Aug 14, 2021, 4:06 PM MDT (22:06 UTC)
Expired
Aug 14, 2021, 4:45 PM MDT
In force
39 min
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Box Butte County, NE, Dawes County, NE, Sioux County, NE

The radar

The Rapid City radar (KUDX), 180 km from the middle of the area, began a volume at 22:10 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

TimeReportWhereRemark
Aug 14, 4:10 PM MDTHAIL 1.253 W Crawford, 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.

IssuedProductOfficeLasted
Aug 14, 3:28 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Rapid City, SD (KUNR), launched 12:00Z, 10.1 hours before the alert went out and 173 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 2021-08-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 911 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Rapid City, SD at 12:00Z on 2021-08-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 93 square meters per square second.193958Sfc1 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
911 J/kg
Mixed-layer CIN
-150 J/kg
Mixed-layer LCL
1691 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
93 m²/s²
0-3 km storm-relative helicity
90 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.7

Open this sounding in Storm Lab

The text

As transmitted.

518 
WUUS55 KCYS 142206
SVRCYS
NEC013-045-165-142245-
/O.NEW.KCYS.SV.W.0119.210814T2206Z-210814T2245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Cheyenne WY
406 PM MDT Sat Aug 14 2021

The National Weather Service in Cheyenne has issued a

* Severe Thunderstorm Warning for...
  Northwestern Box Butte County in the Panhandle of Nebraska...
  Southwestern Dawes County in the Panhandle of Nebraska...
  East central Sioux County in the Panhandle of Nebraska...

* Until 445 PM MDT.

* At 405 PM MDT, a severe thunderstorm was located near Crawford, or
  26 miles southwest of Chadron, moving south at 20 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...
  Crawford, Fort Robinson Campground and Fort Robinson. 

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 4268 10364 4276 10345 4244 10332 4239 10362
TIME...MOT...LOC 2205Z 344DEG 18KT 4264 10345 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MD/GCC
2 follow-up statements
489 
WWUS55 KCYS 142228
SVSCYS

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

NEC013-045-165-142245-
/O.CON.KCYS.SV.W.0119.000000T0000Z-210814T2245Z/
Box Butte NE-Dawes NE-Sioux NE-
428 PM MDT Sat Aug 14 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM MDT
FOR NORTHWESTERN BOX BUTTE...SOUTHWESTERN DAWES AND EAST CENTRAL
SIOUX COUNTIES...

At 428 PM MDT, a severe thunderstorm was located 9 miles south of
Crawford, or 28 miles southwest of Chadron, moving south at 30 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...
Crawford and Fort Robinson. 

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 4265 10357 4271 10343 4244 10332 4239 10362
TIME...MOT...LOC 2228Z 346DEG 24KT 4254 10340 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MD/GCC
444 
WWUS55 KCYS 142242
SVSCYS

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

NEC013-045-165-142251-
/O.EXP.KCYS.SV.W.0119.000000T0000Z-210814T2245Z/
Box Butte NE-Dawes NE-Sioux NE-
442 PM MDT Sat Aug 14 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN BOX BUTTE...
SOUTHWESTERN DAWES AND EAST CENTRAL SIOUX COUNTIES WILL EXPIRE AT 445
PM MDT...
                
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 will be allowed to expire.

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

LAT...LON 4265 10357 4271 10343 4244 10332 4239 10362
TIME...MOT...LOC 2241Z 344DEG 18KT 4250 10339 

$$

MD/GCC

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 14, 3:54 PM MDTSevere Thunderstorm WarningCYSDawes51 min
Aug 14, 4:14 PM MDTSevere Thunderstorm Warning Considerable damage threatCYSDawes46 min
Aug 14, 4:45 PM MDTSevere Thunderstorm WarningCYSBox Butte, Dawes45 min
Aug 14, 4:50 PM MDTSevere Thunderstorm Warning Considerable damage threatCYSBox Butte, Dawes, Sioux40 min
Aug 14, 5:22 PM MDTSevere Thunderstorm Warning Considerable damage threatCYSBox Butte, Morrill, Scotts Bluff, Sioux38 min
Aug 14, 5:52 PM MDTSevere Thunderstorm Warning Destructive damage threatCYSBox Butte, Morrill, Scotts Bluff, Sioux38 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 2021Every 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.