Alert archive / Nebraska / Tornado Warnings in 2013

Tornado Warning 6, NWS Cheyenne, WY

May 18, 2013Morrill County, Nebraska

NWS Cheyenne, WY issued this tornado warning at May 18, 2013, 4:45 PM MDT for Morrill County, Nebraska. It was in force for 30 min. 4 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: May 18, 2013, 4:45 PM MDT (22:45 UTC)
Expired: May 18, 2013, 5:15 PM MDT
In force: 30 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.75 in

County Morrill County, NE

The radar

The Cheyenne radar (KCYS), 181 km from the middle of the area, began a volume at 22:47 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

Time	Report	Where	Remark
May 18, 4:45 PM MDT	FUNNEL CLOUD	14 Ne Bridgeport, NE	WELL DEFINED CONE FUNNEL WITH SEVERE THUNDERSTORM NORTHEAST OF BRIDGEPORT.
May 18, 4:53 PM MDT	FUNNEL CLOUD	9 N Broadwater, NE	BASE OF FUNNEL 40-50 FEET OFF GROUND.
May 18, 4:58 PM MDT	TORNADO	10 N Broadwater, NE
May 18, 5:01 PM MDT	TORNADO	9 N Broadwater, 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.

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

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 10.8 hours before the alert went out and 195 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: 1531 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 568 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 140 m²/s²
0-3 km storm-relative helicity: 163 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 3.7

Open this sounding in Storm Lab

The text

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

444 
WFUS55 KCYS 182245
TORCYS
NEC123-182315-
/O.NEW.KCYS.TO.W.0006.130518T2245Z-130518T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
445 PM MDT SAT MAY 18 2013

THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A

* TORNADO WARNING FOR...
  EAST CENTRAL MORRILL COUNTY IN THE PANHANDLE OF NEBRASKA...

* UNTIL 515 PM MDT

* AT 442 PM MDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED 11 MILES NORTHEAST OF THE INTERSECTION OF
  HIGHWAY 385 AND 92...AND MOVING NORTHEAST AT 10 MPH.

  HAZARD...DEVELOPING TORNADO AND GOLF BALL SIZE HAIL.

  SOURCE...RADAR INDICATED ROTATION.

  IMPACT...MOBILE HOMES WILL BE HEAVILY DAMAGED OR DESTROYED.
           SIGNIFICANT DAMAGE TO ROOFS...WINDOWS AND VEHICLES WILL
           OCCUR. FLYING DEBRIS WILL BE DEADLY TO PEOPLE AND ANIMALS.
           EXTENSIVE TREE DAMAGE IS LIKELY.

* LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF EASTERN MORRILL COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS TORNADO WARNING REPLACES THE SEVERE THUNDERSTORM WARNING THAT
WAS IN EFFECT FOR THE SAME AREA.

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 4161 10279 4170 10300 4196 10282 4189 10267
      4175 10266
TIME...MOT...LOC 2245Z 211DEG 10KT 4173 10283

TORNADO...RADAR INDICATED
HAIL...1.75IN

$$

GRIFFITH

2 follow-up statements

012 
WWUS55 KCYS 182304
SVSCYS

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

NEC123-182315-
/O.CON.KCYS.TO.W.0006.000000T0000Z-130518T2315Z/
MORRILL NE-
504 PM MDT SAT MAY 18 2013

...A TORNADO WARNING REMAINS IN EFFECT FOR EAST CENTRAL MORRILL
COUNTY UNTIL 515 PM MDT...

AT 501 PM MDT...A CONFIRMED TORNADO WAS LOCATED 15 MILES NORTHEAST OF
THE INTERSECTION OF HIGHWAY 385 AND 92...AND MOVING NORTHEAST AT 10
MPH.

HAZARD...DAMAGING TORNADO AND GOLF BALL SIZE HAIL.

SOURCE...RADAR CONFIRMED TORNADO.

IMPACT...MOBILE HOMES WILL BE HEAVILY DAMAGED OR DESTROYED.
         SIGNIFICANT DAMAGE TO ROOFS...WINDOWS AND VEHICLES WILL
         OCCUR. FLYING DEBRIS WILL BE DEADLY TO PEOPLE AND ANIMALS.
         EXTENSIVE TREE DAMAGE IS LIKELY.

LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF EASTERN MORRILL COUNTY.

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.

THIS STORM HAS A HISTORY OF PRODUCING TORNADOES. TAKE COVER IN A
BASEMENT OR STORM SHELTER NOW!

&&

LAT...LON 4161 10279 4170 10300 4196 10282 4189 10267
      4175 10266
TIME...MOT...LOC 2304Z 211DEG 10KT 4177 10279

TORNADO...OBSERVED
HAIL...1.75IN

$$

GRIFFITH

887 
WWUS55 KCYS 182312
SVSCYS

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

NEC123-182322-
/O.EXP.KCYS.TO.W.0006.000000T0000Z-130518T2315Z/
MORRILL NE-
512 PM MDT SAT MAY 18 2013

...THE TORNADO WARNING FOR EAST CENTRAL MORRILL COUNTY WILL EXPIRE AT
515 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 4161 10279 4170 10300 4196 10282 4189 10267
      4175 10266
TIME...MOT...LOC 2312Z 211DEG 10KT 4179 10277

$$

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, 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, 5:52 PM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Dawes	38 min
May 18, 5:56 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne, Morrill	34 min

Nearby

Tornado Warnings in Nebraska, 2013 Every tornado warning in 2013 Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.