Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 13, NWS Great Falls, MT

June 21, 2002Cascade County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jun 21, 2002, 8:08 PM MDT for Cascade County, Montana. It was in force for 37 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 21, 2002, 8:08 PM MDT (02:08 UTC)
Expired
Jun 21, 2002, 8:45 PM MDT
In force
37 min
Issued by
NWS Great Falls, MT
Area
Counties, with a storm outline in the text

County Cascade County, MT

The radar

The Great Falls radar (KTFX), 40 km from the middle of the area, began a volume at 02:11 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.

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 2.1 hours before the alert went out and 72 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 2002-06-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 354 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Great_falls, MT at 00:00Z on 2002-06-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 74 square meters per square second.193958Sfc1 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
354 J/kg
Mixed-layer CIN
-88 J/kg
Mixed-layer LCL
2291 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
74 m²/s²
0-3 km storm-relative helicity
182 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.8

Open this sounding in Storm Lab

The text

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

000 
WUUS55 KTFX 220208 CCA
SVRTFX
MTC013-220245-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING...CORRECTION
NATIONAL WEATHER SERVICE GREAT FALLS MT
801 PM MDT FRI JUN 21 2002

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL CASCADE COUNTY IN CENTRAL MONTANA

* UNTIL 845 PM MDT

* AT 800 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER EXTREME SOUTHWEST CASCADE COUNTY...OR
  ABOUT 22 MILES SOUTH OF CASCADE...MOVING NORTHEAST AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL BE REMAIN OVER...
  RURAL AREAS OF CASCADE COUNTY THROUGH 845 PM.

HAIL UP TO ONE INCH AND WINDS TO 60 MPH ARE POSSIBLE WITH THIS STORM.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN GREAT FALLS.

LAT...LON 4732 11130 4717 11107 4701 11130 4701 11154
          4691 11156 4698 11173

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 7:39 PM MDTSevere Thunderstorm WarningTFXJefferson36 min
Jun 21, 7:45 PM MDTSevere Thunderstorm WarningTFXJefferson30 min
Jun 21, 7:59 PM MDTSevere Thunderstorm WarningTFXBroadwater31 min
Jun 21, 8:03 PM MDTSevere Thunderstorm WarningTFXCascade42 min
Jun 21, 8:07 PM MDTSevere Thunderstorm WarningTFXLewis and Clark23 min
Jun 21, 8:28 PM MDTSevere Thunderstorm WarningTFXMeagher32 min
Jun 21, 8:58 PM MDTSevere Thunderstorm WarningTFXMeagher47 min
Jun 21, 9:11 PM MDTSevere Thunderstorm WarningTFXCascade, Meagher64 min
Jun 21, 9:57 PM MDTSevere Thunderstorm WarningTFXJudith Basin48 min
Jun 22, 2:49 PM MDTSevere Thunderstorm WarningTFXFergus26 min
Jun 22, 3:20 PM MDTSevere Thunderstorm WarningTFXFergus55 min
Jun 22, 4:19 PM MDTSevere Thunderstorm WarningTFXBlaine41 min

Nearby

Severe Thunderstorm Warnings in Montana, 2002Every 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.