Alert archive / Nebraska / Tornado Warnings in 2011

Tornado Warning 20, NWS Cheyenne, WY

July 2, 2011Banner County, Scotts Bluff County, Sioux County, Nebraska; Goshen County, Wyoming

NWS Cheyenne, WY issued this tornado warning at Jul 2, 2011, 7:23 PM MDT for Banner County, Scotts Bluff County, Sioux County, Nebraska; Goshen County, Wyoming. It was in force for 37 min. 5 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
Jul 2, 2011, 7:23 PM MDT (01:23 UTC)
Expired
Jul 2, 2011, 8:00 PM MDT
In force
37 min
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon

Counties Banner County, NE, Scotts Bluff County, NE, Sioux County, NE, Goshen County, WY

The radar

The Cheyenne radar (KCYS), 115 km from the middle of the area, began a volume at 01:23 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
Jul 2, 7:30 PM MDTHAIL 29 Sse Torrington, WYFROM COCORAHS OBSERVER
Jul 2, 7:37 PM MDTTORNADO2 W Lyman, WY
Jul 2, 7:49 PM MDTFUNNEL CLOUD3 W Lyman, WYFUNNEL APPROXIMATELY 75 FEET OFF THE GROUND
Jul 2, 7:59 PM MDTHAIL 1.75Lyman, NE
Jul 2, 8:00 PM MDTHAIL 17 E Lyman, NENO ROTATION.

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
Jul 2, 2:13 PM MDTTornado WatchSPC8 hr

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 1.4 hours before the alert went out and 229 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, Denver, CO at 00:00Z on 2011-07-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 920 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, Denver, CO at 00:00Z on 2011-07-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -51 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
920 J/kg
Mixed-layer CIN
-98 J/kg
Mixed-layer LCL
2294 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
-51 m²/s²
0-3 km storm-relative helicity
-12 m²/s²
Significant tornado parameter
0.0
Supercell composite
-1.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

377 
WFUS55 KCYS 030123
TORCYS
NEC007-157-165-WYC015-030200-
/O.NEW.KCYS.TO.W.0020.110703T0123Z-110703T0200Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
723 PM MDT SAT JUL 2 2011

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* TORNADO WARNING FOR...
  NORTH CENTRAL BANNER COUNTY IN THE PANHANDLE OF NEBRASKA...
  SCOTTS BLUFF COUNTY IN THE PANHANDLE OF NEBRASKA...
  SOUTHWESTERN SIOUX COUNTY IN THE PANHANDLE OF NEBRASKA...
  EAST CENTRAL GOSHEN COUNTY IN SOUTHEAST WYOMING...

* UNTIL 800 PM MDT

* AT 718 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED 7 MILES NORTHWEST OF LYMAN...OR 7 MILES SOUTH OF
  TORRINGTON...AND MOVING SOUTHEAST AT 35 MPH.

  IN ADDITION...AT HAIL TO THE SIZE OF GOLFBALLS WAS REPORTED        
  WITH THIS STORM.

* LOCATIONS IMPACTED INCLUDE...
  SCOTTSBLUFF...LYMAN...MORRILL...STEGALL...MITCHELL...SCOTTS BLUFF
  NATIONAL MONUMENT...TERRYTOWN...GERING...SCOTTSBLUFF AIRPORT AND
  HENRY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4186 10353 4162 10377 4194 10428 4213 10407
TIME...MOT...LOC 0122Z 303DEG 32KT 4194 10412

$$

MAZUR
1 follow-up statement
017 
WWUS55 KCYS 030156
SVSCYS

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
756 PM MDT SAT JUL 2 2011

NEC007-157-165-WYC015-030205-
/O.EXP.KCYS.TO.W.0020.000000T0000Z-110703T0200Z/
BANNER NE-SCOTTS BLUFF NE-GOSHEN WY-SIOUX NE-
756 PM MDT SAT JUL 2 2011

...THE TORNADO WARNING FOR SOUTHWESTERN SIOUX...EAST CENTRAL
GOSHEN...SCOTTS BLUFF AND NORTH CENTRAL BANNER COUNTIES HAS  BEEN 
REISSUED...

PLEASE REFER TO THAT BULLETIN FOR THE LATEST SEVERE WEATHER
INFORMATION.  HOWEVER SMALL HAIL IS STILL POSSIBLE WITH THIS
THUNDERSTORM.

LAT...LON 4186 10353 4162 10377 4194 10428 4213 10407
TIME...MOT...LOC 0155Z 303DEG 32KT 4178 10379

$$

MAZUR

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 2, 6:44 PM MDTSevere Thunderstorm WarningCYSSioux61 min
Jul 2, 6:56 PM MDTTornado WarningCYSSioux49 min
Jul 2, 7:41 PM MDTSevere Thunderstorm WarningCYSBox Butte, Morrill, Scotts Bluff, Sioux49 min
Jul 2, 7:54 PM MDTTornado WarningCYSBanner, Scotts Bluff40 min
Jul 2, 8:25 PM MDTFlash Flood WarningCYSBanner, Scotts Bluff6 hr
Jul 2, 8:30 PM MDTTornado WarningCYSBanner, Kimball, Scotts Bluff45 min
Jul 2, 9:11 PM MDTSevere Thunderstorm WarningCYSBanner, Cheyenne, Kimball, Morrill, Scotts Bluff49 min
Jul 3, 1:55 AM MDTAreal Flood WarningCYSBanner, Scotts Bluff7 hr
Jul 2, 6:04 PM MDTSevere Thunderstorm WarningCYSGoshen, Platte41 min
Jul 2, 6:22 PM MDTTornado WarningCYSGoshen37 min

Nearby

Tornado Warnings in Nebraska, 2011Tornado Warnings in Wyoming, 2011Every tornado warning in 2011Tornadoes in 2011

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.