Alert archive / Nebraska / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 294

May 23, 201210 counties in Kansas; 43 counties in Nebraska

The Storm Prediction Center issued this severe thunderstorm watch at May 23, 2012, 10:47 PM CDT for 10 counties in Kansas; 43 counties in Nebraska. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 23, 2012, 10:47 PM CDT (03:47 UTC)
Expired
May 24, 2012, 5:00 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 53 counties

Decatur County, KS, Graham County, KS, Jewell County, KS, Mitchell County, KS, Norton County, KS, Osborne County, KS, Phillips County, KS, Rooks County, KS, Sheridan County, KS, Smith County, KS, Adams County, NE, Antelope County, NE, Boone County, NE, Buffalo County, NE, Burt County, NE, Butler County, NE, Cedar County, NE, Clay County, NE, Colfax County, NE, Cuming County, NE, Dawson County, NE, Dodge County, NE, Fillmore County, NE, Franklin County, NE, Furnas County, NE, Gosper County, NE, Greeley County, NE, Hall County, NE, Hamilton County, NE, Harlan County, NE, Howard County, NE, Kearney County, NE, Knox County, NE, Madison County, NE, Merrick County, NE, Nance County, NE, Nuckolls County, NE, Phelps County, NE, Pierce County, NE, Platte County, NE, Polk County, NE, Red Willow County, NE, Saunders County, NE, Seward County, NE, Sherman County, NE, Stanton County, NE, Thayer County, NE, Thurston County, NE, Valley County, NE, Washington County, NE, Wayne County, NE, Webster County, NE, York County, NE

The radar

The Grand Island radar (KUEX), 71 km from the middle of the area, began a volume at 03:48 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
20%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
50%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

18 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 23, 10:47 PM CDTSevere Thunderstorm WarningGLDCheyenne, Decatur, Rawlins, Sheridan, Thomas58 min
May 23, 10:52 PM CDTSevere Thunderstorm WarningGIDBuffalo, Dawson, Howard, Sherman38 min
May 23, 10:54 PM CDTSevere Thunderstorm WarningGIDDawson, Gosper, Phelps51 min
May 23, 11:05 PM CDTSevere Thunderstorm WarningGLDDecatur, Sheridan, Thomas40 min
May 23, 11:16 PM CDTSevere Thunderstorm WarningGIDBuffalo, Dawson, Kearney, Phelps44 min
May 23, 11:24 PM CDTSevere Thunderstorm WarningGIDBuffalo, Greeley, Howard, Sherman, Valley51 min
May 23, 11:27 PM CDTSevere Thunderstorm WarningGLDDecatur, Graham, Norton, Rawlins, Sheridan, Thomas63 min
May 23, 11:30 PM CDTSevere Thunderstorm WarningGIDBuffalo, Howard, Sherman45 min
May 23, 11:36 PM CDTSevere Thunderstorm WarningGIDFurnas, Gosper39 min
May 23, 11:45 PM CDTSevere Thunderstorm WarningGLDGove, Logan, Sheridan, Thomas30 min
May 23, 11:53 PM CDTSevere Thunderstorm WarningGIDAdams, Buffalo, Hall, Kearney37 min
May 24, 12:07 AM CDTSevere Thunderstorm WarningGIDBuffalo, Greeley, Hall, Howard, Merrick, Nance and 1 more53 min
May 24, 12:14 AM CDTSevere Thunderstorm WarningGLDGove, Sheridan31 min
May 24, 12:15 AM CDTSevere Thunderstorm WarningGIDFurnas, Gosper, Harlan, Phelps45 min
May 24, 12:28 AM CDTSevere Thunderstorm WarningGIDBuffalo, Hall, Hamilton, Merrick47 min
May 24, 12:29 AM CDTSevere Thunderstorm WarningGLDNorton31 min
May 24, 12:33 AM CDTSevere Thunderstorm WarningGIDPhillips42 min
May 24, 12:47 AM CDTSevere Thunderstorm WarningGIDFranklin, Kearney33 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 3.8 hours before the alert went out and 170 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, Omaha, NE at 00:00Z on 2012-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1035 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 2012-05-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 195 square meters per square second.19395878Sfc1 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
1035 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
2387 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
195 m²/s²
0-3 km storm-relative helicity
291 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.7

Open this sounding in Storm Lab

The text

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

987 
WWUS20 KWNS 240347
SEL4
SPC WW 240347
KSZ000-NEZ000-241000-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 294
NWS STORM PREDICTION CENTER NORMAN OK
1050 PM CDT WED MAY 23 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

       NORTH CENTRAL KANSAS
       CENTRAL AND EASTERN NEBRASKA

EFFECTIVE THIS WEDNESDAY NIGHT AND THURSDAY MORNING FROM 1050 PM
UNTIL 500 AM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 65
STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES NORTHEAST OF
NORFOLK NEBRASKA TO 25 MILES SOUTHEAST OF HILL CITY KANSAS.  FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU4).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION...CONTINUE...WW 293...

DISCUSSION...THUNDERSTORMS CONTINUE TO RE-DEVELOP ACROSS PARTS OF
CENTRAL NEB INTO NORTHWEST KS...IN REGION OF STRONG LOW LEVEL WARM
ADVECTION AND INCREASING LARGE SCALE LIFT.  SUFFICIENT ELEVATED CAPE
ATOP STABLE NEAR-SURFACE LAYER COMBINED WITH STRONG EFFECTIVE SHEAR
WILL PROMOTE INTENSE STORMS CAPABLE OF LARGE HAIL FOR THE NEXT
SEVERAL HOURS.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM
MOTION VECTOR 24030.


...HART

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 23, 8:37 PM CDTMesoscale DiscussionSPCGreeley, Hamilton, Sherman, Wallace83 min
May 23, 10:29 PM CDTMesoscale DiscussionSPCEllis, Graham, Jewell, Mitchell, Norton, Osborne and 4 more91 min
May 23, 8:56 PM CDTMesoscale DiscussionSPCAdams, Burt, Butler, Cass, Clay, Colfax and 31 more94 min

Nearby

Severe Thunderstorm Watches in Nebraska, 2012Severe Thunderstorm Watches in Kansas, 2012Every severe thunderstorm watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.