Alert archive / Montana / Severe Thunderstorm Watches in 2001

Severe Thunderstorm Watch 551

July 13, 200116 counties in Montana

The Storm Prediction Center issued this severe thunderstorm watch at Jul 13, 2001, 2:15 PM MDT for 16 counties in Montana. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jul 13, 2001, 2:15 PM MDT (20:15 UTC)
Expired
Jul 13, 2001, 7:00 PM MDT
In force
5 hr
Issued by
the Storm Prediction Center

Counties Broadwater County, MT, Cascade County, MT, Chouteau County, MT, Deer Lodge County, MT, Gallatin County, MT, Granite County, MT, Jefferson County, MT, Judith Basin County, MT, Lewis and Clark County, MT, Madison County, MT, Meagher County, MT, Park County, MT, Pondera County, MT, Powell County, MT, Silver Bow County, MT, Teton County, MT

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 13, 2:52 PM MDTSevere Thunderstorm WarningTFXGallatin28 min
Jul 13, 5:20 PM MDTSevere Thunderstorm WarningTFXLewis and Clark40 min
Jul 13, 5:43 PM MDTSevere Thunderstorm WarningMSOSilver Bow37 min
Jul 13, 5:57 PM MDTSevere Thunderstorm WarningTFXJefferson48 min
Jul 13, 6:05 PM MDTSevere Thunderstorm WarningTFXCascade, Meagher40 min
Jul 13, 6:42 PM MDTSevere Thunderstorm WarningTFXCascade, Judith Basin48 min

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 8.3 hours before the alert went out and 177 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 2001-07-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 100 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 2001-07-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 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
100 J/kg
Mixed-layer CIN
-251 J/kg
Mixed-layer LCL
1561 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
41 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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 12, 6:15 PM MDTSevere Thunderstorm WatchSPCBlaine, Fergus, Garfield, Hill, McCone, Petroleum and 3 more6 hr
Jul 13, 1:30 PM MDTSevere Thunderstorm WatchSPCBig Horn, Blaine, Carbon, Fergus, Garfield, Golden Valley and 12 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.