Tornado Watch 447

Issued

Jun 24, 2007, 4:06 PM MDT (22:06 UTC)

Expired

Jun 24, 2007, 11:00 PM MDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

4 in

Strongest gust expected

70 kt

The Billings radar (KBLX), 118 km from the middle of the area, began a volume at 22:05 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

80%

One or more EF2 to EF5 tornadoes

40%

Ten or more severe wind reports

40%

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

90%

• Mesoscale Discussion 1267Jun 24, 2:46 PM MDT
• Mesoscale Discussion 1270Jun 24, 6:48 PM MDT
• Mesoscale Discussion 1273Jun 24, 9:47 PM MDT

000
WWUS20 KWNS 242209
SEL7  
SPC WW 242209
MTZ000-WYZ000-250500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 447
NWS STORM PREDICTION CENTER NORMAN OK
405 PM MDT SUN JUN 24 2007

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

       LARGE PART OF EASTERN MONTANA
       SMALL PART OF NORTHEAST WYOMING

EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 405 PM UNTIL
1100 PM MDT.

TORNADOES...HAIL TO 4 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 110 STATUTE
MILES EITHER SIDE OF A LINE FROM 45 MILES WEST NORTHWEST OF
BILLINGS MONTANA TO 20 MILES SOUTH SOUTHEAST OF BAKER MONTANA. 
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU7).

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.

DISCUSSION...EXTREME INSTABILITY  WITH MLCAPES IN EXCESS OF 3500
J/KG COUPLED WITH STRONGLY VEERING SHEAR PROFILES  ARE IN PLACE
ACROSS MUCH OF WATCH AREA ATTM.  THE CAP IS WEAKENING OVER THE
HIGHER TERRAIN AND EXPECT RAPID DEVELOPMENT OF SEVERE THUNDERSTORMS.
 TORNADIC SUPERCELLS ARE LIKELY TO DEVELOP ACCOMPANIED BY VERY LARGE
HAIL AND DAMAGING WINDS.  ACTIVITY WILL SPREAD EWD ACROSS THE WATCH
THRU THE EVENING TOWARD THE DAKOTA BORDER WHERE SIMILAR CONDITIONS
ARE PRESENT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 4 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
600. MEAN STORM MOTION VECTOR 24035.


...HALES

Tornado Watches in Montana, 2007Tornado Watches in Wyoming, 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.