Alert archive / Montana / Severe Thunderstorm Watches in 2003

Severe Thunderstorm Watch 548

June 20, 200318 counties in Montana

The Storm Prediction Center issued this severe thunderstorm watch at Jun 20, 2003, 12:05 PM MDT for 18 counties in Montana. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Jun 20, 2003, 12:05 PM MDT (18:05 UTC)
Expired
Jun 20, 2003, 8:00 PM MDT
In force
8 hr
Issued by
the Storm Prediction Center

Counties Blaine County, MT, Broadwater County, MT, Carbon County, MT, Cascade County, MT, Chouteau County, MT, Fergus County, MT, Gallatin County, MT, Golden Valley County, MT, Hill County, MT, Judith Basin County, MT, Liberty County, MT, Madison County, MT, Meagher County, MT, Park County, MT, Stillwater County, MT, Sweet Grass County, MT, Toole County, MT, Wheatland County, MT

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jun 20, 12:13 PM MDTSevere Thunderstorm WarningTFXCascade47 min
Jun 20, 12:55 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau, Teton35 min
Jun 20, 1:30 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau, Liberty, Pondera, Toole45 min
Jun 20, 2:14 PM MDTSevere Thunderstorm WarningTFXHill, Liberty46 min
Jun 20, 2:25 PM MDTSevere Thunderstorm WarningTFXFergus, Judith Basin35 min
Jun 20, 2:47 PM MDTSevere Thunderstorm WarningTFXChouteau, Hill43 min
Jun 20, 3:26 PM MDTSevere Thunderstorm WarningTFXBlaine, Hill64 min
Jun 20, 4:00 PM MDTSevere Thunderstorm WarningTFXFergus60 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 6.1 hours before the alert went out and 36 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 2003-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 29 joules per kilogram.LCLLFCEL10008507005003002001001 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 2003-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -7 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
29 J/kg
Mixed-layer CIN
-308 J/kg
Mixed-layer LCL
1255 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
162 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 20, 11:36 AM MDTMesoscale DiscussionSPCBlaine, Broadwater, Carbon, Cascade, Chouteau, Fergus and 17 more114 min
Jun 20, 2:39 PM MDTMesoscale DiscussionSPCBlaine, Broadwater, Cascade, Chouteau, Fergus, Gallatin and 9 more96 min
Jun 20, 3:25 PM MDTMesoscale DiscussionSPCBig Horn, Carter, Custer, Daniels, Dawson, Fallon and 15 more65 min
Jun 20, 3:30 PM MDTSevere Thunderstorm WatchSPCBig Horn, Carter, Custer, Daniels, Dawson, Fallon and 15 more8 hr
Jun 20, 4:43 PM MDTMesoscale DiscussionSPCBig Horn, Blaine, Carter, Custer, Daniels, Dawson and 16 more62 min

Nearby

Severe Thunderstorm Watches in Montana, 2003Every severe thunderstorm watch in 2003

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.