Severe Thunderstorm Watch 548

Issued

Aug 1, 2012, 2:19 PM MDT (20:19 UTC)

Expired

Aug 1, 2012, 8:39 PM MDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

65 kt

The North Platte radar (KLNX), 140 km from the middle of the area, began a volume at 20:19 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

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

30%

One or more hailstones of 2 inches or more

20%

Six or more combined severe hail and wind reports

70%

• Mesoscale Discussion 1672Aug 1, 1:53 PM MDT
• Mesoscale Discussion 1675Aug 1, 3:14 PM MDT
• Mesoscale Discussion 1677Aug 1, 6:35 PM MDT
• Mesoscale Discussion 1679Aug 1, 7:19 PM MDT

204 
WWUS20 KWNS 012021
SEL8
SPC WW 012021
NEZ000-SDZ000-020400-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 548
NWS STORM PREDICTION CENTER NORMAN OK
320 PM CDT WED AUG 1 2012

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

       NORTHERN NEBRASKA
       SOUTH-CENTRAL AND EASTERN SOUTH DAKOTA

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 320 PM UNTIL
1100 PM CDT.

HAIL TO 2 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 75
STATUTE MILES EAST AND WEST OF A LINE FROM 25 MILES WEST
SOUTHWEST OF MULLEN NEBRASKA TO 60 MILES NORTH NORTHWEST OF HURON
SOUTH DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).

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 544...WW 546...WW 547...

DISCUSSION...STORMS WILL CONTINUE TO INCREASE IN BOTH INTENSITY AND
COVERAGE AHEAD AND ALONG A COLD FRONT AND LEE TROUGH DEVELOPING INTO
THE WATCH AREA. AIRMASS ACROSS SD AND NEB HAS BECOME MODERATELY TO
STRONGLY UNSTABLE WITH LATEST MLCAPE ESTIMATES BETWEEN 1500-2000 J
PER KG. CONVECTION WILL DEVELOP EAST AIDED BY LARGE SCALE ASCENT
ACCOMPANYING A SHORTWAVE TROUGH CROSSING THE NRN PLAINS THROUGH
TONIGHT. DEEP-LAYER SHEAR WILL BE SUFFICIENT FOR BOTH SUPERCELLS AND
LONGER-LIVED LINE SEGMENTS WITH ATTENDANT THREATS OF LARGE HAIL AND
HIGH WINDS.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 65
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM
MOTION VECTOR 27030.


...CARBIN

Severe Thunderstorm Watches in South Dakota, 2012Severe Thunderstorm Watches in Nebraska, 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.