Tornado Watch 81

Issued

Mar 28, 2007, 1:33 PM MDT (19:33 UTC)

Expired

Mar 28, 2007, 8:50 PM MDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

Counties Phillips County, CO, Sedgwick County, CO, Box Butte County, NE, Cheyenne County, NE, Dawes County, NE, Morrill County, NE, Bennett County, SD, Custer County, SD, Fall River County, SD, Haakon County, SD, Jackson County, SD, Mellette County, SD, Pennington County, SD, Todd County, SD

The North Platte radar (KLNX), 160 km from the middle of the area, began a volume at 19:36 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

70%

One or more EF2 to EF5 tornadoes

30%

Ten or more severe wind reports

50%

One or more gusts of 65 knots or more

30%

Ten or more severe hail reports

80%

One or more hailstones of 2 inches or more

50%

Six or more combined severe hail and wind reports

95%

• Mesoscale Discussion 360Mar 28, 1:04 PM MDT
• Mesoscale Discussion 362Mar 28, 5:10 PM MDT
• Mesoscale Discussion 366Mar 28, 8:06 PM MDT

000
WWUS20 KWNS 281936
SEL1  
SPC WW 281936
COZ000-NEZ000-SDZ000-290300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 81
NWS STORM PREDICTION CENTER NORMAN OK
135 PM MDT WED MAR 28 2007

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

       EXTREME NORTHEAST COLORADO
       WESTERN NEBRASKA
       SOUTHWEST SOUTH DAKOTA

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 135 PM UNTIL
900 PM MDT.

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

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE
MILES EAST AND WEST OF A LINE FROM 85 MILES NORTH NORTHEAST OF
CHADRON NEBRASKA TO 10 MILES SOUTHEAST OF IMPERIAL NEBRASKA.  FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU1).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.

OTHER WATCH INFORMATION...CONTINUE...WW 80...

DISCUSSION...INITIAL THUNDERSTORM DEVELOPMENT IS COMMENCING ALONG
THE SURFACE TRIPLE POINT NEAR SCOTTS BLUFF.  CONVECTION WILL LIKELY
INCREASE ACROSS WRN NEB THROUGH THE AFTERNOON AS THE LOW LEVELS
CONTINUE TO WARM/DESTABILIZE...AND ADDITIONAL CONVECTION SHOULD
DEVELOP/SPREAD NWD/NNEWD INTO SW SD.  VERTICAL SHEAR IS ALREADY
QUITE FAVORABLE FOR SUPERCELLS...AND SHOULD REMAIN STRONG THROUGH
THE EVENING TO THE E/NE OF THE PRIMARY SURFACE CYCLONE.  GIVEN
BOUNDARY LAYER DEWPOINTS IN THE LOW-MID 50S AND SUBSTANTIAL
LOW-LEVEL SHEAR...THE SUPERCELLS WILL BE CAPABLE OF PRODUCING
TORNADOES AND LARGE HAIL.  ALSO...CONVECTION MAY GROW INTO ONE OR
MORE LINE SEGMENTS BY LATE AFTERNOON/EVENING THROUGH STORM
MERGERS...WITH THE POTENTIAL FOR A FEW BOWING SEGMENTS WITH DAMAGING
WINDS.

AVIATION...TORNADOES AND 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 19045.


...THOMPSON

Tornado Watches in South Dakota, 2007Tornado Watches in Nebraska, 2007Tornado Watches in Colorado, 2007Every tornado watch in 2007

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.