Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 30, NWS Great Falls, MT

June 28, 2002Beaverhead County, Madison County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jun 28, 2002, 4:43 PM MDT for Beaverhead County, Madison County, Montana. It was in force for 47 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: Jun 28, 2002, 4:43 PM MDT (22:43 UTC)
Expired: Jun 28, 2002, 5:30 PM MDT
In force: 47 min
Issued by: NWS Great Falls, MT
Area: Counties, with a storm outline in the text

Counties Beaverhead County, MT, Madison County, MT

The radar

The Pocatello radar (KSFX), 230 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.

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, 10.7 hours before the alert went out and 294 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2115 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: -52 m²/s²
0-3 km storm-relative helicity: 87 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.

000 
WUUS55 KTFX 282243
SVRTFX
MTC001-057-282330-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
442 PM MDT FRI JUN 28 2002

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL BEAVERHEAD COUNTY IN SOUTHWEST MONTANA
  WEST CENTRAL MADISON COUNTY IN SOUTHWEST MONTANA

* UNTIL 530 PM MDT

* AT 440 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 10 MILES SOUTH OF DILLON...MOVING NORTHEAST AT
  20 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  DILLON AT 455 PM MDT

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH YOU SHOULD PREPARE
FOR DAMAGING WINDS IN EXCESS OF 55 MPH...LARGE HAIL...AND DEADLY
LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...PREFERABLY
INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

LAT...LON 4509 11277 4496 11259 4519 11196 4551 11241

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 Jun 28, 2:50 PM MDT, 1 hour 53 minutes earlier.

Area forecast discussion, Jun 28, 2:50 PM MDT, 1 hour 53 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
250 PM MDT FRI JUN 28 2002

.SHORT TERM...FLOW ALOFT IS W-SW OVER THE CWA THIS AFTERNOON. THERE
IS QUITE A BIT OF CLOUD COVER THIS AFTERNOON...WHICH IS KEEPING
TEMPERATURES DOWN. COOLER TEMPS MAY END UP INHIBITING EVENING
CONVECTION SOMEWHAT...HOWEVER THE ETA MODEL BRINGS A FAIRLY STRONG
VORTICITY LOBE OVER THE STATE THIS EVENING...AND THIS COULD BE
POWERFUL ENOUGH TO OFFSET LACK OF HEATING. WILL KEEP SCATTERED POPS
OUT...BUT IT MAY BE TOUGH TO GENERATE SEVERE WEATHER GIVEN THE
SMALLER DEW POINT DEPRESSIONS AND CONTINUED HIGH WET BULB ZERO
HEIGHT. AN EVEN STRONGER VORTICITY LOBE MOVES OVER THE STATE BY EARLY
AFTERNOON SATURDAY...AND IS ACCOMPANIED BY A SURFACE COLD FRONT.
SCATTERED MORNING SHOWERS ARE POSSIBLE AHEAD OF THE FRONT...BUT 700
MB WEST WINDS OF 30 TO 40 KTS WILL LIKELY DOWNSLOPE OFF THE ROCKIES
AND COUNTERACT ANY LIFT GIVEN BY THE UPPER LEVEL DYNAMICS. BEHIND
THE FRONT...SKIES WILL CLEAR AND MODERATE DOWNSLOPE WINDS WILL
EFFECTIVELY SUPPRESS ANY PRECIPITATION DURING THE AFTERNOON. THE
AIRMASS DRIES OUT SIGNIFICANTLY SUNDAY AND MONDAY...AND THE AIRMASS
REMAINS STABLE...SO EXPECT NO CHANCE OF PRECIPITATION DURING THIS
TIME PERIOD. MPJ

EXTENDED...SOUTHWEST FLOW ALOFT WILL PERSIST OVER THE CWA THROUGH
THE EXTENDED PERIOD. TUESDAY LOOKS TO BE DRY AS A SHORT WAVE RIDGE
SWINGS THROUGH THE REGION. THERE WILL BE A CHANCE OF AFTERNOON AND
EVENING THUNDERSTORMS WEDNESDAY THROUGH FRIDAY UNDER THE SOUTHWEST
FLOW. TEMPERATURES DURING THIS PERIOD WILL REMAIN NEAR NORMAL. MEIER

.CCF NUMBERS
GTF NU 058/078 050/082 050 14440
    BBBBB 080/045 078/048 082/048 080/048 080 00011133333
CTB NU 056/074 048/076 050 14430
    BBBBB 075/042 077/046 078/048 078/048 078 00011133333
HLN NU 058/080 050/084 052 14441
    BBBBB 082/050 080/050 082/050 082/050 082 00011133333
BZN BU 052/082 045/084 047 14332
    BBBBB 082/045 077/049 080/049 080/049 081 00011133333
WEY BU 044/078 040/072 040 14221
    BBBBB 073/041 076/045 075/045 075/045 075 00011133333
DLN NU 053/077 044/082 048 14231
    BBBBB 081/045 078/048 080/050 082/050 082 00011133333
HVR NU 060/080 052/083 052 14430
    BBBBB 081/048 078/050 082/050 082/050 082 00011133333
LWT NU 057/078 048/081 050 14441
    BBBBB 079/044 079/050 080/050 080/050 080 00011133333=

.TFX...FLOOD WARNING CONTINUES FOR GLACIER COUNTY (ZONES 9 AND 10).

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 27, 6:11 PM MDT	Severe Thunderstorm Warning	TFX	Toole	34 min
Jun 27, 7:06 PM MDT	Severe Thunderstorm Warning	TFX	Pondera, Teton	39 min
Jun 27, 7:08 PM MDT	Severe Thunderstorm Warning	TFX	Glacier	52 min
Jun 27, 7:20 PM MDT	Severe Thunderstorm Warning	TFX		40 min
Jun 27, 8:09 PM MDT	Severe Thunderstorm Warning	TFX	Toole	51 min
Jun 27, 8:56 PM MDT	Severe Thunderstorm Warning	TFX	Hill	34 min
Jun 27, 9:08 PM MDT	Severe Thunderstorm Warning	TFX	Blaine, Fergus	37 min

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.