Alert archive / Montana / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 575

August 4, 200227 counties in Montana

The Storm Prediction Center issued this severe thunderstorm watch at Aug 4, 2002, 2:40 PM MDT for 27 counties in Montana. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Aug 4, 2002, 2:40 PM MDT (20:40 UTC)
Expired
Aug 4, 2002, 8:00 PM MDT
In force
5 hr
Issued by
the Storm Prediction Center
All 27 counties

Big Horn County, MT, Blaine County, MT, Broadwater County, MT, Carbon County, MT, Cascade County, MT, Chouteau County, MT, Fergus County, MT, Gallatin County, MT, Glacier County, MT, Golden Valley County, MT, Hill County, MT, Jefferson County, MT, Judith Basin County, MT, Lewis and Clark County, MT, Liberty County, MT, Madison County, MT, Meagher County, MT, Musselshell County, MT, Park County, MT, Petroleum County, MT, Pondera County, MT, Stillwater County, MT, Sweet Grass County, MT, Teton County, MT, Toole County, MT, Wheatland County, MT, Yellowstone County, MT

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Aug 4, 4:14 PM MDTSevere Thunderstorm WarningTFXGallatin46 min
Aug 4, 4:39 PM MDTSevere Thunderstorm WarningTFXBroadwater36 min
Aug 4, 4:49 PM MDTSevere Thunderstorm WarningTFXLewis and Clark56 min
Aug 4, 5:49 PM MDTSevere Thunderstorm WarningTFXMeagher41 min
Aug 4, 6:17 PM MDTSevere Thunderstorm WarningBYZWheatland58 min
Aug 4, 7:02 PM MDTSevere Thunderstorm WarningTFXFergus, Judith Basin58 min

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 8.7 hours before the alert went out and 51 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 2002-08-04Temperature 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 2002-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 52 square meters per square second.1939587897Sfc1 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
863 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
52 m²/s²
0-3 km storm-relative helicity
106 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 4, 4:20 PM MDTSevere Thunderstorm WatchSPCCarter, Custer, Dawson, Fallon, Garfield, McCone and 6 more6 hr

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.