Alert archive / Montana / Tornado Watches in 2002

Tornado Watch 499

July 8, 20028 counties in Montana

The Storm Prediction Center issued this tornado watch at Jul 8, 2002, 4:45 PM MDT for 8 counties in Montana. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Jul 8, 2002, 4:45 PM MDT (22:45 UTC)
Expired: Jul 8, 2002, 10:00 PM MDT
In force: 5 hr
Issued by: the Storm Prediction Center

Counties Blaine County, MT, Fergus County, MT, Garfield County, MT, McCone County, MT, Musselshell County, MT, Petroleum County, MT, Phillips County, MT, Valley County, MT

The radar

The Glasgow radar (KGGW), 54 km from the middle of the area, began a volume at 22:46 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.

Warnings issued inside it

16 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Jul 8, 4:51 PM MDT	Severe Thunderstorm Warning	GGW	Petroleum	54 min
Jul 8, 4:52 PM MDT	Tornado Warning	TFX	Blaine	53 min
Jul 8, 5:01 PM MDT	Tornado Warning	GGW	Petroleum	59 min
Jul 8, 5:02 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	43 min
Jul 8, 5:44 PM MDT	Tornado Warning	GGW	Garfield	61 min
Jul 8, 5:59 PM MDT	Severe Thunderstorm Warning	GGW	Petroleum	61 min
Jul 8, 6:36 PM MDT	Severe Thunderstorm Warning	GGW	Valley	54 min
Jul 8, 6:48 PM MDT	Severe Thunderstorm Warning	GGW	Garfield	57 min
Jul 8, 6:51 PM MDT	Severe Thunderstorm Warning	GGW	Phillips	54 min
Jul 8, 7:15 PM MDT	Severe Thunderstorm Warning	GGW	Valley	60 min
Jul 8, 7:23 PM MDT	Tornado Warning	GGW	Valley	52 min
Jul 8, 7:24 PM MDT	Severe Thunderstorm Warning	GGW	McCone	51 min
Jul 8, 7:43 PM MDT	Severe Thunderstorm Warning	GGW	Garfield	62 min
Jul 8, 8:10 PM MDT	Severe Thunderstorm Warning	GGW	Valley	65 min
Jul 8, 8:12 PM MDT	Severe Thunderstorm Warning	GGW	McCone	63 min
Jul 8, 8:15 PM MDT	Severe Thunderstorm Warning	GGW	McCone	60 min

The nearest sounding before it

Glasgow Intl Airport, MT (KGGW), launched 12:00Z, 10.8 hours before the alert went out and 56 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 214 J/kg
Mixed-layer CIN: -246 J/kg
Mixed-layer LCL: 1201 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 119 m²/s²
0-3 km storm-relative helicity: 185 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WWUS20 KWNS 082227
SEL9  
WWUS20 KWNS 082224
SPC WW 082224
MTZ000-090400-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 499
STORM PREDICTION CENTER NORMAN OK
424 PM MDT MON JUL 8 2002

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

   CENTRAL AND EASTERN MONTANA                            

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 445 PM UNTIL 1000
PM MDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 90 STATUTE MILES EAST AND WEST
OF A LINE FROM 75 MILES NORTHWEST OF GLASGOW MONTANA TO 75 MILES
WEST OF MILES CITY MONTANA.

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...THIS TORNADO WATCH REPLACES SEVERE
THUNDERSTORM WATCH NUMBER 498.  WATCH NUMBER 498 WILL NOT BE IN
EFFECT AFTER 445 PM MDT.

DISCUSSION...SEVERE THUNDERSTORMS CONTINUE TO INTENSIFY OVER
CENTRAL MT AHEAD OF VIGOROUS S/WV TROUGH. WITH STG VEERING SHEAR
PROFILES AND VERY UNSTABLE AIR MASS IN PLACE ACROSS ERN
MT...POTENTIAL FOR TORNADIC SUPERCELLS EXPECTED TO INCREASE AS
STORMS MOVE E/NE.


AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600. 
MEAN STORM MOTION VECTOR 24035.


...HALES

485,1054 462,1053 462,1092 485,1094

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 8, 1:00 PM MDT	Severe Thunderstorm Watch	SPC	Blaine, Cascade, Chouteau, Fergus, Garfield, Hill and 8 more	6 hr

Nearby

Tornado Watches in Montana, 2002 Every tornado watch in 2002

Sources

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.