Tornado Watch 400

Issued

Jun 16, 2007, 2:18 PM MDT (20:18 UTC)

Expired

Jun 16, 2007, 10:00 PM MDT

In force

8 hr

Issued by

the Storm Prediction Center

Largest hail expected

3 in

Strongest gust expected

60 kt

The Great Falls radar (KTFX), 65 km from the middle of the area, began a volume at 20:20 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

50%

One or more EF2 to EF5 tornadoes

20%

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 1165Jun 16, 1:37 PM MDT
• Mesoscale Discussion 1167Jun 16, 6:02 PM MDT
• Mesoscale Discussion 1168Jun 16, 6:59 PM MDT

000
WWUS20 KWNS 162020
SEL0  
SPC WW 162020
MTZ000-170400-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 400
NWS STORM PREDICTION CENTER NORMAN OK
220 PM MDT SAT JUN 16 2007

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

       CENTRAL MONTANA

EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 220 PM UNTIL
1000 PM MDT.

TORNADOES...HAIL TO 3 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 105 STATUTE
MILES EAST AND WEST OF A LINE FROM 65 MILES NORTH NORTHEAST OF
GREAT FALLS MONTANA TO 65 MILES SOUTHWEST OF BILLINGS MONTANA. 
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU0).

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...SEVERE THUNDERSTORMS WILL INCREASE IN COVERAGE AND
INTENSITY DURING THE NEXT HOUR OR SO AND SPREAD ENEWD THROUGH THE
EVENING. ENVIRONMENT STRONGLY FAVORS SUPERCELLS WITH VERY STRONG
SHEAR AND INCREASING MLCAPE THROUGH THE EARLY EVENING.  LARGE
HAIL...SOME EXCEEDING 2 INCHES IN DIAMETER...ALONG WITH ISOLATED
DAMAGING WINDS WILL BE COMMON WITH THESE STORMS.  TORNADO THREAT
WILL ALSO INCREASE INTO THE EARLY EVENING AS STORMS INTERACT WITH
ELY SURFACE WINDS AND RICHER LOW LEVEL MOISTURE ALREADY IN PLACE
OVER CENTRAL MT.  LATER THIS EVENING...ONE OR MORE BOW ECHO
COMPLEXES MAY EVOLVE INCREASING THE RISK OF DAMAGING WINDS.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 24025.


...EVANS

Tornado Watches in Montana, 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.