Alert archive / Montana / Tornado Warnings in 2002

Tornado Warning 8, NWS Great Falls, MT

August 5, 2002Chouteau County, Montana

NWS Great Falls, MT issued this tornado warning at Aug 5, 2002, 6:45 PM MDT for Chouteau County, Montana. It was in force for 30 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 5, 2002, 6:45 PM MDT (00:45 UTC)
Expired
Aug 5, 2002, 7:15 PM MDT
In force
30 min
Issued by
NWS Great Falls, MT
Area
Counties, with a storm outline in the text

County Chouteau County, MT

The radar

The Great Falls radar (KTFX), 98 km from the middle of the area, began a volume at 00:48 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.

What was reported inside it

TimeReportWhereRemark
Aug 5, 7:00 PM MDTHail 0.88Square Butte, MTA severe thunderstorm produced 0.88 inch hail near Square Butte.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 5, 3:55 PM MDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 0.8 hours before the alert went out and 41 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-pSkew-T log-p diagram, Great_falls, MT at 00:00Z on 2002-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 568 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Great_falls, MT at 00:00Z on 2002-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 30 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
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
568 J/kg
Mixed-layer CIN
-156 J/kg
Mixed-layer LCL
1251 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
30 m²/s²
0-3 km storm-relative helicity
301 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.7

Open this sounding in Storm Lab

The text

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

117 
WFUS55 KTFX 060045
TORTFX
MTC015-060115-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
644 PM MDT MON AUG 5 2002

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTH CENTRAL CHOUTEAU COUNTY IN NORTH CENTRAL MONTANA

* UNTIL 715 PM MDT

* AT 638 PM MDT...DOPPLER RADAR INDICATED A TORNADO 12 MILES SOUTH 
OF GERALDINE...OR ABOUT 20 MILES NORTH OF STANFORD...MOVING 
NORTHEAST AT 35 MPH. THIS STORM HAS PRODUCED ONE TORNADO NORTH OF 
GEYSER.

* THE TORNADO IS EXPECTED TO BE NEAR...
  6 MILES SOUTHEAST OF GERALDINE AT 655 PM MDT

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM MDT
MONDAY EVENING FOR WESTERN MONTANA.

LAT...LON 4743 11047 4743 11018 4756 10988 4772 10986
          4779 10976 4790 10998 4772 11025

The office that day

Everything else NWS Great Falls, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 5, 6:07 PM MDTSevere Thunderstorm WarningTFXTeton53 min
Aug 5, 6:18 PM MDTTornado WarningTFXJudith Basin27 min
Aug 5, 6:48 PM MDTSevere Thunderstorm WarningTFXCascade57 min
Aug 5, 6:51 PM MDTSevere Thunderstorm WarningTFXPondera54 min
Aug 5, 6:59 PM MDTTornado WarningTFXChouteau46 min
Aug 5, 7:03 PM MDTSevere Thunderstorm WarningTFXFergus57 min
Aug 5, 7:27 PM MDTSevere Thunderstorm WarningTFXTeton48 min
Aug 5, 7:29 PM MDTSevere Thunderstorm WarningTFXToole46 min
Aug 5, 7:32 PM MDTTornado WarningTFXFergus58 min
Aug 5, 7:48 PM MDTSevere Thunderstorm WarningTFXChouteau57 min
Aug 5, 7:58 PM MDTSevere Thunderstorm WarningTFXLiberty62 min
Aug 5, 8:45 PM MDTSevere Thunderstorm WarningTFXFergus30 min
Aug 5, 9:18 PM MDTSevere Thunderstorm WarningTFXFergus57 min
Aug 6, 4:57 PM MDTSevere Thunderstorm WarningTFXFergus63 min
Aug 6, 5:11 PM MDTTornado WarningTFXFergus64 min

Nearby

Tornado Warnings in Montana, 2002Every tornado warning in 2002Tornadoes 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.