Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 113, NWS Great Falls, MT

August 20, 2002Judith Basin County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Aug 20, 2002, 8:24 PM MDT for Judith Basin County, Montana. It was in force for 36 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 20, 2002, 8:24 PM MDT (02:24 UTC)
Expired
Aug 20, 2002, 9:00 PM MDT
In force
36 min
Issued by
NWS Great Falls, MT
Area
Counties, with a storm outline in the text

County Judith Basin County, MT

The radar

The Great Falls radar (KTFX), 114 km from the middle of the area, began a volume at 02:23 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, 2.4 hours before the alert went out and 77 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 2002-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 87 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 2002-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 16 square meters per square second.19395878Sfc1 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
87 J/kg
Mixed-layer CIN
-122 J/kg
Mixed-layer LCL
2116 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
16 m²/s²
0-3 km storm-relative helicity
200 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.

966 
WUUS55 KTFX 210224
SVRTFX
MTC045-210300-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
823 PM MDT TUE AUG 20 2002

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN JUDITH BASIN COUNTY IN CENTRAL MONTANA

* UNTIL 900 PM MDT

* AT 818 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER EXTREME SOUTH CENTRAL JUDITH BASIN
  COUNTY...OR ABOUT 28 MILES NORTHEAST OF WHITE SULPHUR SPRINGS...
  MOVING NORTHEAST AT 35 MPH.

* THE SEVERE THUNDERSTORM WILL REMAIN OVER...RURAL SOUTHERN JUDITH 
BASIN COUNTY.

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 4682 11055 4669 11038 4678 10983 4689 10986
          4693 11003

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 6:55 PM MDTSevere Thunderstorm WarningTFXBroadwater, Meagher50 min
Aug 20, 8:02 PM MDTSevere Thunderstorm WarningTFXJudith Basin58 min
Aug 20, 8:58 PM MDTSevere Thunderstorm WarningTFXFergus, Judith Basin62 min
Aug 21, 3:04 PM MDTSevere Thunderstorm WarningTFXJefferson, Madison56 min
Aug 21, 4:21 PM MDTSevere Thunderstorm WarningTFXJudith Basin39 min
Aug 21, 4:46 PM MDTSevere Thunderstorm WarningTFXFergus44 min
Aug 21, 5:13 PM MDTSevere Thunderstorm WarningTFXBeaverhead47 min
Aug 21, 5:15 PM MDTSevere Thunderstorm WarningTFXBeaverhead45 min
Aug 21, 5:30 PM MDTSevere Thunderstorm WarningTFXFergus60 min
Aug 21, 5:43 PM MDTSevere Thunderstorm WarningTFXMadison47 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.