Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 126, NWS Great Falls, MT

August 29, 2002Chouteau County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Aug 29, 2002, 5:38 PM MDT for Chouteau County, Montana. It was in force for 52 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 29, 2002, 5:38 PM MDT (23:38 UTC)
Expired: Aug 29, 2002, 6:30 PM MDT
In force: 52 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), 71 km from the middle of the area, began a volume at 23:38 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 11.6 hours before the alert went out and 49 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: 52 J/kg
Mixed-layer CIN: -184 J/kg
Mixed-layer LCL: 1593 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: -10 m²/s²
0-3 km storm-relative helicity: -43 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

826 
WUUS55 KTFX 292338
SVRTFX
MTC015-300030-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
540 PM MDT THU AUG 29 2002

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL CHOUTEAU COUNTY IN NORTH CENTRAL MONTANA
  THIS INCLUDES THE CITY OF FORT BENTON

* UNTIL 630 PM MDT

* AT 540 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A SEVERE THUNDERSTORM NEAR FORT BENTON...MOVING NORTH AT 10 MPH.

HAIL...INTENSE RAIN AND STRONG DAMAGING WINDS ARE LIKELY WITH THIS 
STORM. TAKE COVER IN A SUBSTANTIAL SHELTER UNTIL THE STORM PASSES.

LAT...LON 4779 11088 4766 11069 4816 11020 4810 11084

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Great Falls, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 29, 4:13 PM MDT, 1 hour 25 minutes earlier.

Area forecast discussion, Aug 29, 4:13 PM MDT, 1 hour 25 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
300 PM MDT THU AUG 29 2002

.SHORT TERM...UPPER LOW CONTINUES TO LIFT OUT OVER NORTHWEST
MONTANA. SOUTHWEST FLOW ALOFT HAS KICKED OFF SOME CONVECTIVE
ACTIVITY OVER THE SOUTHWEST. WOULD EXPECT THUNDERSTORMS TO MOVE OFF
THE MOUNTAINS AND OVER THE PLAINS THIS EVENING. UPPER LOW LIFTS OUT
AS ANOTHER UPPER TROF APPROACHES WESTERN MONTANA FRIDAY. SOME
CONVECTIVE ACTIVITY LIKELY TO DEVELOP AGAIN FRIDAY NIGHT OVER
SOUTHWEST MONTANA AND MOVE NORTH SATURDAY AS THE TROF SWINGS ACROSS.
WEAK RIDGING DEVELOPS SUNDAY FOR DRIER CONDITIONS. TEMPERATURES TO
REMAIN NEAR SEASONAL NORMS. EMANUEL

.EXTENDED...UPPER LEVEL TROF TO MOVE OVER MAINLY NORTHERN ZONES ON
MONDAY WITH A DRY AND SUNNY FORECAST FOR TUESDAY. SOUTHWEST FLOW
RETURNS ON WEDNESDAY WITH ANOTHER UPPER LEVEL TROF TO MOVE OVER THE
AREA ON THURSDAY. MOISTURE AT THIS TIME NOT IMPRESSIVE SO WILL ONLY
GO FOR ISOLATED THUNDERSTORMS WEDNESDAY NIGHT AND THURSDAY. CAMP

.CCF NUMBERS
GTF BB 052/080 052/075 048 08412
    BBUBB 077/046 071/048 077/048 074/044 071 32211001222
CTB BB 050/078 047/073 046 08312
    BEUBB 075/042 068/044 074/044 071/041 068 21121001112
HLN BB 057/083 054/081 052 08413
    BBUBB 082/051 075/053 081/053 078/045 077 32211001222
BZN BB 051/078 046/075 045 08623
    BBUBB 077/043 073/045 079/047 079/043 070 32211001222
WEY BB 038/067 036/066 037 08623
    BBUBB 070/035 069/037 075/039 075/035 068 32211001222
DLN BB 050/078 046/075 045 08623
    BBUBB 077/044 072/046 078/048 075/044 070 32211001222
HVR BB 054/083 053/078 050 08412
    BEUBB 080/046 074/048 080/050 080/043 075 21221001112
LWT BB 052/080 052/076 048 08413
    BEUBB 077/044 071/046 077/048 077/043 073 32211001222

.TFX...NONE.

In the hours before

Special weather statement, Aug 29, 1:20 PM MDT, 4 hours 18 minutes before

MTZ008>015-044>055-300130-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREAT FALLS MT
120 PM MDT THU AUG 29 2002

...LOCALLY HEAVY RAIN...GUSTY WINDS AND HAIL POSSIBLE WITH
THUNDERSTORMS THIS AFTERNOON AND EVENING...

THUNDERSTORMS WILL DEVELOP THIS AFTERNOON OVER SOUTHWEST AND NORTH
CENTRAL MONTANA. AS THE STORMS INCREASE IN COVERAGE AND
INTENSITY...THE STRONGER THUNDERSTORMS WILL BE CAPABLE OF
GENERATING WIND GUSTS TO 60 MPH...HAIL TO ONE INCH IN DIAMETER AND
LOCALLY HEAVY RAINS.

INITIAL THUNDERSTORM ACTIVITY WILL LIKELY DEVELOP OVER THE SOUTHWEST
MOUNTAINS BETWEEN 1 PM AND 3 PM...THEN SPREAD TO THE NORTHEAST. THE
STORMS IMPACTING NORTH CENTRAL MONTANA ARE EXPECTED TO DEVELOP
BETWEEN 4 PM AND 6PM AND CONTINUE TO AFFECT THE AREA THROUGH 9 PM.

STAY TUNED TO THIS STATION FOR FURTHER UPDATES.

Local storm report, Aug 29, 4:01 PM MDT, 1 hour 37 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
401 PM MDT THU AUG 29 2002

TIME(MDT)  .....EVENT  LOCATION..... ST   ...EVENT/REMARKS...........
           .....COUNTY LOCATION.....

0350 PM    HOBSON                    MT   0.25 INCH HAIL
08/29/02   JUDITH  BASIN

NNNN

Nearby

Severe Thunderstorm Warnings in Montana, 2002 Every severe thunderstorm warning 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.