Alert archive / Montana / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 579

August 5, 200219 counties in Montana

The Storm Prediction Center issued this severe thunderstorm watch at Aug 5, 2002, 3:55 PM MDT for 19 counties in Montana. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Aug 5, 2002, 3:55 PM MDT (21:55 UTC)
Expired
Aug 5, 2002, 10:00 PM MDT
In force
6 hr
Issued by
the Storm Prediction Center

Counties Broadwater County, MT, Cascade County, MT, Chouteau County, MT, Deer Lodge County, MT, Glacier County, MT, Granite County, MT, Hill County, MT, Jefferson County, MT, Judith Basin County, MT, Lewis and Clark County, MT, Liberty County, MT, Meagher County, MT, Pondera County, MT, Powell County, MT, Silver Bow County, MT, Sweet Grass County, MT, Teton County, MT, Toole County, MT, Wheatland County, MT

The radar

The Great Falls radar (KTFX), 55 km from the middle of the area, began a volume at 21:57 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.

Warnings issued inside it

13 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Aug 5, 5:16 PM MDTSevere Thunderstorm WarningTFXLewis and Clark44 min
Aug 5, 5:36 PM MDTSevere Thunderstorm WarningTFXLewis and Clark54 min
Aug 5, 5:52 PM MDTSevere Thunderstorm WarningTFXJudith Basin38 min
Aug 5, 6:07 PM MDTSevere Thunderstorm WarningTFXTeton53 min
Aug 5, 6:18 PM MDTTornado WarningTFXJudith Basin27 min
Aug 5, 6:45 PM MDTTornado WarningTFXChouteau30 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, 7:27 PM MDTSevere Thunderstorm WarningTFXTeton48 min
Aug 5, 7:29 PM MDTSevere Thunderstorm WarningTFXToole46 min
Aug 5, 7:48 PM MDTSevere Thunderstorm WarningTFXChouteau57 min
Aug 5, 7:58 PM MDTSevere Thunderstorm WarningTFXLiberty62 min

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 9.9 hours before the alert went out and 98 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 12:00Z on 2002-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 2002-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 135 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
992 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
135 m²/s²
0-3 km storm-relative helicity
308 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

Nearby

Severe Thunderstorm Watches in Montana, 2002Every severe thunderstorm watch 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.