Alert archive / Nebraska / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 5, NWS Cheyenne, WY

May 20, 20214 counties in Nebraska

NWS Cheyenne, WY issued this severe thunderstorm warning at May 20, 2021, 7:55 PM MDT for 4 counties in Nebraska. It was in force for 39 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: May 20, 2021, 7:55 PM MDT (01:55 UTC)
Expired: May 20, 2021, 8:34 PM MDT
In force: 39 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Banner County, NE, Cheyenne County, NE, Kimball County, NE, Morrill County, NE

The radar

The Cheyenne radar (KCYS), 126 km from the middle of the area, began a volume at 01:55 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

Denver, CO (KDNR), launched 00:00Z, 1.9 hours before the alert went out and 143 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: 66 J/kg
Mixed-layer CIN: -60 J/kg
Mixed-layer LCL: 3320 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 41 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.

365 
WUUS55 KCYS 210155
SVRCYS
NEC007-033-105-123-210245-
/O.NEW.KCYS.SV.W.0005.210521T0155Z-210521T0245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Cheyenne WY
755 PM MDT Thu May 20 2021

The National Weather Service in Cheyenne has issued a

* Severe Thunderstorm Warning for...
  Western Cheyenne County in the Panhandle of Nebraska...
  Eastern Kimball County in the Panhandle of Nebraska...
  Southwestern Morrill County in the Panhandle of Nebraska...
  Southeastern Banner County in the Panhandle of Nebraska...

* Until 845 PM MDT.

* At 755 PM MDT, a severe thunderstorm was located 11 miles south of
  Potter, or 18 miles southeast of Kimball, moving northeast at 35
  mph.

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

  SOURCE...Trained weather spotters.

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

* Locations impacted include...
  Potter, Dalton, Gurley and Brownson. 

This includes Interstate 80 in Nebraska between mile markers 31 and
52.
 
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 4101 10351 4146 10343 4144 10285 4101 10317
      4100 10333
TIME...MOT...LOC 0155Z 207DEG 31KT 4106 10340 

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

Claycomb

2 follow-up statements

571 
WWUS55 KCYS 210224
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
824 PM MDT Thu May 20 2021

NEC007-033-105-123-210245-
/O.CON.KCYS.SV.W.0005.000000T0000Z-210521T0245Z/
Cheyenne NE-Kimball NE-Morrill NE-Banner NE-
824 PM MDT Thu May 20 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 PM MDT
FOR WESTERN CHEYENNE...EASTERN KIMBALL...SOUTHWESTERN MORRILL AND
SOUTHEASTERN BANNER COUNTIES...

At 823 PM MDT, a severe thunderstorm was located near Potter, or 17
miles northwest of Sidney, moving northeast at 35 mph.

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

SOURCE...Trained weather spotters.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Potter, Dalton, Gurley and Brownson. 

This includes Interstate 80 in Nebraska between mile markers 31 and
52.
 
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 4101 10351 4146 10343 4144 10285 4101 10317
      4100 10333
TIME...MOT...LOC 0223Z 207DEG 31KT 4128 10325 

HAIL...0.75IN
WIND...60MPH
 
$$

Claycomb

903 
WWUS55 KCYS 210234
SVSCYS

Severe Weather Statement
National Weather Service Cheyenne WY
834 PM MDT Thu May 20 2021

NEC007-033-105-123-210243-
/O.CAN.KCYS.SV.W.0005.000000T0000Z-210521T0245Z/
Cheyenne NE-Kimball NE-Morrill NE-Banner NE-
834 PM MDT Thu May 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN CHEYENNE...EASTERN
KIMBALL...SOUTHWESTERN MORRILL AND SOUTHEASTERN BANNER COUNTIES IS
CANCELLED...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning has
been cancelled.

LAT...LON 4101 10351 4146 10343 4144 10285 4101 10317
      4100 10333
TIME...MOT...LOC 0231Z 207DEG 31KT 4136 10319 

$$

Claycomb

The office that day

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

Issued	Product	Office	Counties	Lasted
May 20, 6:10 PM MDT	Special Weather Statement	CYS	Banner	50 min
May 20, 6:49 PM MDT	Special Weather Statement	CYS	Scotts Bluff	41 min
May 20, 6:54 PM MDT	Special Weather Statement	CYS	Kimball	51 min
May 20, 7:07 PM MDT	Severe Thunderstorm Warning	CYS	Scotts Bluff, Sioux	38 min
May 20, 7:15 PM MDT	Severe Thunderstorm Warning	CYS	Banner, Cheyenne, Kimball	45 min
May 20, 8:36 PM MDT	Severe Thunderstorm Warning	CYS	Banner, Cheyenne, Kimball	24 min
May 21, 4:10 PM MDT	Special Weather Statement	CYS	Dawes	50 min
May 21, 4:28 PM MDT	Special Weather Statement	CYS	Box Butte	47 min
May 21, 4:38 PM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Dawes	52 min
May 21, 5:26 PM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Morrill, Scotts Bluff, Sioux	49 min
May 21, 5:32 PM MDT	Severe Thunderstorm Warning	CYS	Dawes	43 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.