Severe Thunderstorm Watch 281

Issued

May 19, 2012, 3:25 PM CDT (20:25 UTC)

Expired

May 19, 2012, 10:00 PM CDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

2.5 in

Strongest gust expected

65 kt

The Grand Island radar (KUEX), 91 km from the middle of the area, began a volume at 20:29 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.

Two or more tornadoes

10%

One or more EF2 to EF5 tornadoes

2%

Ten or more severe wind reports

60%

One or more gusts of 65 knots or more

30%

Ten or more severe hail reports

60%

One or more hailstones of 2 inches or more

20%

Six or more combined severe hail and wind reports

80%

• Mesoscale Discussion 839May 19, 2:36 PM CDT
• Mesoscale Discussion 840May 19, 5:41 PM CDT
• Mesoscale Discussion 842May 19, 7:03 PM CDT
• Mesoscale Discussion 843May 19, 8:11 PM CDT
• Mesoscale Discussion 844May 19, 9:18 PM CDT

943 
WWUS20 KWNS 192029
SEL1
SPC WW 192029
IAZ000-KSZ000-NEZ000-200300-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 281
NWS STORM PREDICTION CENTER NORMAN OK
325 PM CDT SAT MAY 19 2012

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

       SOUTHWEST IOWA
       CENTRAL AND EASTERN KANSAS
       SOUTH CENTRAL AND EASTERN NEBRASKA

EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 325 PM UNTIL
1000 PM CDT.

HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 75
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 25 MILES WEST
NORTHWEST OF TEKAMAH NEBRASKA TO 30 MILES EAST SOUTHEAST OF
MEDICINE LODGE KANSAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE
THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).

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.

DISCUSSION...THUNDERSTORMS ARE BEGINNING TO DEVELOP OVER CENTRAL KS
ALONG A COLD FRONT IN RESPONSE TO INCREASING LARGE SCALE ASCENT IN
ADVANCE OF AN UPPER TROUGH MOVING INTO THE CENTRAL PLAINS.  STRONG
HEATING COUPLED WITH FOCUSED UPWARD MOTION IS EXPECTED TO CONTINUE
WEAKENING THE CAP WITH ADDITIONAL STORMS DEVELOPING NWD INTO PARTS
OF NEB.  STEEP LAPSE RATES ARE CONTRIBUTING TO MLCAPE OF 1500-2000
J/KG...AND 30-40 KT SHEAR WILL ENHANCE STORM INTENSITY AND
ORGANIZATION.  LARGE HAIL WILL BE LIKELY WITH STRONGER CELLS...AND
PRESENCE OF A RELATIVELY DEEP AND WELL-MIXED PBL WILL PROMOTE SEVERE
WIND GUSTS AS WELL.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 65
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 24025.


...WEISS

Severe Thunderstorm Watches in Kansas, 2012Severe Thunderstorm Watches in Nebraska, 2012Severe Thunderstorm Watches in Iowa, 2012Every severe thunderstorm watch in 2012

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.