Alert archive / Nebraska / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 21, NWS Cheyenne, WY

May 18, 2013Box Butte County, Dawes County, Nebraska

NWS Cheyenne, WY issued this severe thunderstorm warning at May 18, 2013, 5:52 PM MDT for Box Butte County, Dawes County, Nebraska. It was in force for 38 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 18, 2013, 5:52 PM MDT (23:52 UTC)
Expired: May 18, 2013, 6:30 PM MDT
In force: 38 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

The radar

The Rapid City radar (KUDX), 180 km from the middle of the area, began a volume at 23:54 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 18, 1:42 PM MDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Rapid City, SD (KUNR), launched 12:00Z, 11.9 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-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: 277 J/kg
Mixed-layer CIN: -205 J/kg
Mixed-layer LCL: 922 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 75 m²/s²
0-3 km storm-relative helicity: -2 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -1.3

Open this sounding in Storm Lab

The text

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

490 
WUUS55 KCYS 182352
SVRCYS
NEC013-045-190030-
/O.NEW.KCYS.SV.W.0021.130518T2352Z-130519T0030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
552 PM MDT SAT MAY 18 2013

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL BOX BUTTE COUNTY IN THE PANHANDLE OF NEBRASKA...
  SOUTHEASTERN DAWES COUNTY IN THE PANHANDLE OF NEBRASKA...

* UNTIL 630 PM MDT

* AT 550 PM MDT...A SEVERE THUNDERSTORM WAS LOCATED 8 MILES EAST OF
  BOX BUTTE DAM...AND MOVING NORTH AT 5 MPH.

  HAZARD...QUARTER SIZE HAIL AND 60 MPH WIND GUSTS.

  SOURCE...RADAR INDICATED.

  IMPACT...HAIL DAMAGE TO VEHICLES AND CROPS IS EXPECTED. EXPECT WIND
           DAMAGE TO ROOFS...SIDING AND TREES.

* LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF SOUTHEASTERN DAWES COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMAIN ALERT FOR A POSSIBLE TORNADO! TORNADOES CAN DEVELOP QUICKLY
FROM SEVERE THUNDERSTORMS. IF YOU SPOT A TORNADO GO AT ONCE INTO THE
BASEMENT OR SMALL CENTRAL ROOM IN A STURDY STRUCTURE.

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

LARGE HAIL...DAMAGING WINDS AND CONTINUOUS CLOUD TO GROUND LIGHTNING
IS OCCURRING WITH THIS STORM. MOVE INDOORS IMMEDIATELY. LIGHTNING
KILLS. REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO
BE STRUCK BY LIGHTNING.

&&

LAT...LON 4235 10282 4237 10306 4274 10293 4274 10277
TIME...MOT...LOC 2353Z 188DEG 6KT 4245 10293

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

$$

GRIFFITH

1 follow-up statement

307 
WWUS55 KCYS 190020
SVSCYS

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
620 PM MDT SAT MAY 18 2013

NEC013-045-190031-
/O.EXP.KCYS.SV.W.0021.000000T0000Z-130519T0030Z/
BOX BUTTE NE-DAWES NE-
620 PM MDT SAT MAY 18 2013

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN DAWES AND NORTH
CENTRAL BOX BUTTE COUNTIES WILL EXPIRE AT 630 PM MDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 10 PM MDT.

LAT...LON 4235 10282 4237 10306 4274 10293 4274 10277
TIME...MOT...LOC 0021Z 188DEG 6KT 4250 10292

$$

GRIFFITH

The office that day

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

Issued	Product	Office	Counties	Lasted
May 17, 10:47 PM MDT	Special Weather Statement	CYS	Box Butte	43 min
May 18, 2:54 PM MDT	Severe Thunderstorm Warning	CYS	Dawes, Sioux	51 min
May 18, 3:38 PM MDT	Special Weather Statement	CYS	Cheyenne	37 min
May 18, 3:50 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne, Kimball	40 min
May 18, 3:51 PM MDT	Special Weather Statement	CYS	Dawes	54 min
May 18, 3:55 PM MDT	Severe Thunderstorm Warning	CYS	Dawes	50 min
May 18, 4:12 PM MDT	Tornado Warning	CYS	Dawes	33 min
May 18, 4:14 PM MDT	Severe Thunderstorm Warning	CYS	Sioux	46 min
May 18, 4:17 PM MDT	Severe Thunderstorm Warning	CYS	Morrill	43 min
May 18, 4:18 PM MDT	Special Weather Statement	CYS	Cheyenne	27 min
May 18, 4:23 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne, Kimball	52 min
May 18, 4:35 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne, Kimball	40 min
May 18, 4:45 PM MDT	Tornado Warning	CYS	Morrill	30 min
May 18, 5:10 PM MDT	Severe Thunderstorm Warning	CYS	Dawes	20 min
May 18, 5:13 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne, Morrill	47 min
May 18, 5:23 PM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Morrill	52 min
May 18, 5:33 PM MDT	Severe Thunderstorm Warning	CYS	Morrill	27 min
May 18, 5:38 PM MDT	Severe Thunderstorm Warning	CYS	Sioux	52 min
May 18, 5:56 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne, Morrill	34 min

Nearby

Severe Thunderstorm Warnings in Nebraska, 2013 Every severe thunderstorm warning in 2013

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.