Severe Thunderstorm Watch 515

Issued

Jul 24, 2012, 7:01 PM MDT (01:01 UTC)

Expired

Jul 25, 2012, 2:00 AM MDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

The Bismarck radar (KBIS), 81 km from the middle of the area, began a volume at 01:01 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 1575Jul 24, 4:42 PM MDT
• Mesoscale Discussion 1578Jul 24, 10:24 PM MDT

661 
WWUS20 KWNS 250102
SEL5
SPC WW 250102
NDZ000-SDZ000-250800-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 515
NWS STORM PREDICTION CENTER NORMAN OK
705 PM MDT TUE JUL 24 2012

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

       WESTERN AND CENTRAL NORTH DAKOTA
       NORTHWEST AND NORTH-CENTRAL SOUTH DAKOTA

EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 705 PM
UNTIL 200 AM MDT.

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 60
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 65 MILES WEST
SOUTHWEST OF DICKINSON NORTH DAKOTA TO 30 MILES SOUTH SOUTHEAST
OF JAMESTOWN NORTH DAKOTA.  FOR A COMPLETE DEPICTION OF THE WATCH
SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).

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 514...

DISCUSSION...TSTMS ARE EXPECTED TO INCREASE IN COVERAGE AND
INTENSITY THIS EVENING ALONG COOL SIDE OF SURFACE BOUNDARY WHERE THE
00Z BIS SOUNDING SHOWED A SUBSTANTIALLY WEAKER CAP THAN THAT
OBSERVED AT UNR AND ABR.  GIVEN THE MOIST...MODERATELY UNSTABLE AIR
MASS IN PLACE AND 40-50 KT OF DEEP-LAYER SHEAR...SETUP WILL FAVOR
EVOLUTION OF SUPERCELL AND BOWING STRUCTURES WITH A RISK FOR LARGE
HAIL AND DAMAGING WINDS.

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 500. MEAN STORM
MOTION VECTOR 28015.


...MEAD

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