Alert archive / Nebraska / Tornado Warnings in 2012

Tornado Warning 20, NWS North Platte, NE

May 4, 2012Custer County, Nebraska

NWS North Platte, NE issued this tornado warning at May 4, 2012, 10:12 PM CDT for Custer County, Nebraska. It was in force for 16 min. 1 report 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 4, 2012, 10:12 PM CDT (03:12 UTC)
Expired: May 4, 2012, 10:28 PM CDT
In force: 16 min
Issued by: NWS North Platte, NE
Area: Storm-based polygon

County Custer County, NE

The radar

The Grand Island radar (KUEX), 111 km from the middle of the area, began a volume at 03:12 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 4, 10:27 PM CDT	HAIL 1.25	4 S Mason City, 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 4, 2:00 PM CDT	Severe Thunderstorm Watch	SPC	9 hr

The nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 3.2 hours before the alert went out and 113 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: 171 J/kg
Mixed-layer CIN: -54 J/kg
Mixed-layer LCL: 3007 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 6 m²/s²
0-3 km storm-relative helicity: 82 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

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

961 
WFUS53 KLBF 050312
TORLBF
NEC041-050345-
/O.NEW.KLBF.TO.W.0020.120505T0312Z-120505T0345Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1012 PM CDT FRI MAY 4 2012

THE NATIONAL WEATHER SERVICE IN NORTH PLATTE HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHEASTERN CUSTER COUNTY IN CENTRAL NEBRASKA...

* UNTIL 1045 PM CDT

* AT 1009 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED NEAR LITCHFIELD...OR 28 MILES SOUTHEAST OF BROKEN
  BOW...AND MOVING SOUTHEAST AT 15 MPH.

* LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF EXTREME SOUTHEASTERN CUSTER 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.

&&

LAT...LON 4104 9921 4104 9933 4121 9938 4129 9920
      4105 9920
TIME...MOT...LOC 0312Z 325DEG 12KT 4112 9923

$$

MASEK

2 follow-up statements

896 
WWUS53 KLBF 050321
SVSLBF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1021 PM CDT FRI MAY 4 2012

NEC041-050345-
/O.CON.KLBF.TO.W.0020.000000T0000Z-120505T0345Z/
CUSTER NE-
1021 PM CDT FRI MAY 4 2012

...A TORNADO WARNING REMAINS IN EFFECT FOR SOUTHEASTERN CUSTER COUNTY
UNTIL 1045 PM CDT...

AT 1018 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS 
STORM WAS 7 MILES SOUTHEAST OF MASON CITY...OR 30 MILES 
SOUTHEAST OF BROKEN BOW...MOVING SOUTHEAST AT 15 MPH.

LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF EXTREME SOUTHEASTERN CUSTER COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HEAVY RAINFALL MAY OBSCURE THIS TORNADO. DO NOT WAIT TO SEE OR HEAR
THE TORNADO. TAKE COVER NOW.

TORNADOES ARE DIFFICULT TO SEE AND CONFIRM AT NIGHT. TAKE COVER NOW.

&&

LAT...LON 4104 9921 4104 9933 4121 9938 4129 9920
      4105 9920
TIME...MOT...LOC 0320Z 319DEG 10KT 4112 9922

$$

MASEK

258 
WWUS53 KLBF 050328
SVSLBF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1028 PM CDT FRI MAY 4 2012

NEC041-050337-
/O.CAN.KLBF.TO.W.0020.000000T0000Z-120505T0345Z/
CUSTER NE-
1028 PM CDT FRI MAY 4 2012

...THE TORNADO WARNING FOR SOUTHEASTERN CUSTER COUNTY IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.  HOWEVER SMALL HAIL IS STILL POSSIBLE WITH THIS THUNDERSTORM.

IN ADDITION...STRONG THUNDERSTORMS MAY REDEVELOP...AND A SEVERE 
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 11 PM CDT.

LAT...LON 4104 9921 4104 9933 4121 9938 4129 9920
      4105 9920
TIME...MOT...LOC 0327Z 319DEG 10KT 4111 9920

$$

MASEK

The office that day

Everything else NWS North Platte, NE issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 4, 7:02 PM CDT	Severe Thunderstorm Warning	LBF	Garfield, Wheeler	58 min
May 4, 8:52 PM CDT	Severe Thunderstorm Warning	LBF	Custer	38 min
May 4, 8:54 PM CDT	Severe Thunderstorm Warning	LBF	Wheeler	18 min
May 4, 9:47 PM CDT	Severe Thunderstorm Warning	LBF	Custer	43 min
May 4, 10:59 PM CDT	Severe Thunderstorm Warning	LBF	Custer	21 min
May 5, 7:33 AM CDT	Dense Fog Advisory	LBF	Blaine, Boyd, Brown, Garfield, Holt, Keya Paha and 3 more	4 hr

Nearby

Tornado Warnings in Nebraska, 2012 Every tornado warning in 2012 Tornadoes in 2012

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.