Alert archive / Montana / Severe Thunderstorm Watches in 2001

Severe Thunderstorm Watch 552

July 13, 200120 counties in Montana

The Storm Prediction Center issued this severe thunderstorm watch at Jul 13, 2001, 7:00 PM MDT for 20 counties in Montana. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Jul 13, 2001, 7:00 PM MDT (01:00 UTC)
Expired
Jul 14, 2001, 1:00 AM MDT
In force
6 hr
Issued by
the Storm Prediction Center

Counties Blaine County, MT, Broadwater County, MT, Cascade County, MT, Chouteau County, MT, Fergus County, MT, Garfield County, MT, Golden Valley County, MT, Hill County, MT, Judith Basin County, MT, Liberty County, MT, Meagher County, MT, Musselshell County, MT, Petroleum County, MT, Phillips County, MT, Stillwater County, MT, Sweet Grass County, MT, Treasure County, MT, Valley County, MT, Wheatland County, MT, Yellowstone County, MT

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 13, 7:33 PM MDTSevere Thunderstorm WarningBYZMusselshell57 min
Jul 13, 7:35 PM MDTSevere Thunderstorm WarningBYZStillwater55 min
Jul 13, 8:00 PM MDTSevere Thunderstorm WarningBYZBig Horn, Yellowstone60 min
Jul 13, 8:55 PM MDTSevere Thunderstorm WarningBYZBig Horn, Treasure65 min
Jul 13, 9:25 PM MDTSevere Thunderstorm WarningBYZYellowstone65 min

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 1.0 hours before the alert went out and 109 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 2001-07-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 113 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 00:00Z on 2001-07-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 21 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
113 J/kg
Mixed-layer CIN
-40 J/kg
Mixed-layer LCL
2628 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
21 m²/s²
0-3 km storm-relative helicity
59 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 13, 11:00 PM MDTSevere Thunderstorm WatchSPCCarter, Custer, Fallon, Powder River, Rosebud4 hr
Jul 14, 5:00 PM MDTSevere Thunderstorm WatchSPCBig Horn, Carbon, Custer, Golden Valley, Musselshell, Powder River and 3 more6 hr

Nearby

Severe Thunderstorm Watches in Montana, 2001Every severe thunderstorm watch in 2001

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.