Alert archive / Montana / Severe Thunderstorm Watches in 2003

Severe Thunderstorm Watch 852

August 8, 20037 counties in Montana

The Storm Prediction Center issued this severe thunderstorm watch at Aug 8, 2003, 4:35 PM MDT for 7 counties in Montana. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Aug 8, 2003, 4:35 PM MDT (22:35 UTC)
Expired
Aug 8, 2003, 10:00 PM MDT
In force
5 hr
Issued by
the Storm Prediction Center

Counties Fergus County, MT, Garfield County, MT, Golden Valley County, MT, McCone County, MT, Musselshell County, MT, Petroleum County, MT, Treasure County, MT

The radar

The Glasgow radar (KGGW), 152 km from the middle of the area, began a volume at 22:36 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

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

IssuedProductOfficeCountiesLasted
Aug 8, 4:45 PM MDTSevere Thunderstorm WarningBYZGolden Valley30 min
Aug 8, 5:26 PM MDTSevere Thunderstorm WarningTFXFergus49 min
Aug 8, 5:28 PM MDTSevere Thunderstorm WarningBYZMusselshell32 min
Aug 8, 6:03 PM MDTTornado WarningBYZMusselshell27 min
Aug 8, 9:16 PM MDTSevere Thunderstorm WarningGGWGarfield59 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, 10.6 hours before the alert went out and 197 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 2003-08-08Temperature 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 2003-08-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 17 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1701 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
17 m²/s²
0-3 km storm-relative helicity
192 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 7, 9:11 PM MDTMesoscale DiscussionSPCBlaine, Daniels, Dawson, Garfield, Hill, McCone and 7 more64 min
Aug 8, 1:48 PM MDTMesoscale DiscussionSPCDawson, Richland, Roosevelt, Sheridan, Wibaux117 min
Aug 8, 3:40 PM MDTSevere Thunderstorm WatchSPCDawson, Richland, Roosevelt, Sheridan, Wibaux6 hr

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; radar from the NEXRAD Level II archive.