Alert archive / Nebraska / Special Weather Statements in 2021

Special Weather Statement, NWS Cheyenne, WY

July 16, 2021Box Butte County, Nebraska

NWS Cheyenne, WY issued this special weather statement at Jul 16, 2021, 9:31 PM MDT for Box Butte County, Nebraska. It was in force for 44 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 16, 2021, 9:31 PM MDT (03:31 UTC)
Expired
Jul 16, 2021, 10:15 PM MDT
In force
44 min
Issued by
NWS Cheyenne, WY

County Box Butte County, NE

The radar

The North Platte radar (KLNX), 191 km from the middle of the area, began a volume at 03:30 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 00:00Z, 3.5 hours before the alert went out and 216 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 00:00Z on 2021-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Rapid City, SD at 00:00Z on 2021-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 73 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3551 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
73 m²/s²
0-3 km storm-relative helicity
211 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

999 
WWUS85 KCYS 170331
SPSCYS

Special Weather Statement
National Weather Service Cheyenne WY
931 PM MDT Fri Jul 16 2021
 
NEZ003-170415-
Box Butte NE-
931 PM MDT Fri Jul 16 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN BOX BUTTE COUNTY
UNTIL 1015 PM MDT...

At 931 PM MDT, Doppler radar was tracking a strong thunderstorm over
Berea, or 7 miles northwest of Alliance, moving east at 20 mph.

Half inch hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Alliance, Wild Horse Butte, Berea and Alliance Airport. 

LAT...LON 4203 10280 4203 10306 4208 10316 4217 10314
      4225 10305 4231 10275 4230 10274 4210 10274
      4209 10271 4205 10270
TIME...MOT...LOC 0331Z 264DEG 16KT 4220 10295 

$$

Mokry

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 5:25 PM MDTSpecial Weather StatementCYSNiobrara35 min
Jul 16, 6:59 PM MDTSpecial Weather StatementCYSDawes31 min
Jul 16, 7:10 PM MDTSevere Thunderstorm WarningCYSDawes35 min
Jul 16, 7:33 PM MDTSevere Thunderstorm WarningCYSBox Butte, Dawes42 min
Jul 17, 4:20 PM MDTSpecial Weather StatementCYSSioux40 min
Jul 17, 4:59 PM MDTSpecial Weather StatementCYSSioux31 min
Jul 17, 5:03 PM MDTSpecial Weather StatementCYSKimball27 min
Jul 17, 5:29 PM MDTSpecial Weather StatementCYSKimball31 min

Nearby

Special Weather Statements in Nebraska, 2021Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.