Tornado Watch 421

Issued

Jun 6, 2005, 4:15 PM MDT (22:15 UTC)

Expired

Jun 6, 2005, 11:00 PM MDT

In force

7 hr

Issued by

the Storm Prediction Center

Counties Dawson County, MT, Garfield County, MT, McCone County, MT, Phillips County, MT, Prairie County, MT, Richland County, MT, Roosevelt County, MT, Valley County, MT, Wibaux County, MT, Billings County, ND, Dunn County, ND, Golden Valley County, ND, McKenzie County, ND, Mercer County, ND, Mountrail County, ND, Stark County, ND, Williams County, ND

The Glasgow radar (KGGW), 84 km from the middle of the area, began a volume at 22:17 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.

• Mesoscale Discussion 1204Jun 6, 2:15 PM MDT
• Mesoscale Discussion 1215Jun 6, 9:12 PM MDT

000 
WWUS20 KWNS 062214
SEL1  
SPC WW 062214
MTZ000-NDZ000-070500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 421
NWS STORM PREDICTION CENTER NORMAN OK
415 PM MDT MON JUN 6 2005

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

       NORTHEAST MONTANA
       WESTERN NORTH DAKOTA

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 415 PM UNTIL 1100
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 70 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 75 MILES WEST SOUTHWEST OF GLASGOW
MONTANA TO 20 MILES SOUTH OF ROSEGLEN NORTH DAKOTA.  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 415...WW 416...WW 417...WW
418...WW 419...WW 420...

DISCUSSION...PRESSURE IS FALLING RAPIDLY ACROSS THE AREA NORTHEAST
OF A LOW OVER NERN WY. AIR MASS IS VERY UNSTABLE WITH MLCAPE 2000
TO 3500 J/KG AND BRN SHEAR NUMBERS ARE 80 TO 100.  SHEAR NUMBERS ARE
ENHANCED DUE TO ELY-LIKE FLOW N OF THE BOUNDARY...BUT AS MID LEVEL
SHORTWAVE TROUGH MOVES NWD INTO AREA...WINDS WILL BECOME SELY
KEEPING FAVORABLE SHEAR PROFILES ACROSS THE AREA FOR POSSIBILITY OF
TORNADOES.

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 550.
MEAN STORM MOTION VECTOR 21030.


...MCCARTHY

484,1080 482,1015 462,1015 464,1080

Tornado Watches in Montana, 2005Tornado Watches in North Dakota, 2005Every tornado watch in 2005

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.