Alert archive / Montana / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 30, NWS Missoula, MT

August 4, 2001Powell County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Aug 4, 2001, 1:54 PM MDT for Powell County, Montana. It was in force for 51 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued
Aug 4, 2001, 1:54 PM MDT (19:54 UTC)
Expired
Aug 4, 2001, 2:45 PM MDT
In force
51 min
Issued by
NWS Missoula, MT
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Powell County, MT

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 7.9 hours before the alert went out and 205 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 2001-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 38 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 2001-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -70 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
38 J/kg
Mixed-layer CIN
-272 J/kg
Mixed-layer LCL
2483 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
-70 m²/s²
0-3 km storm-relative helicity
-33 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS55 KMSO 041956
SVRMSO

MTC077-042045-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
154 PM MDT SAT AUG 4 2001

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL POWELL COUNTY IN WEST CENTRAL MONTANA

* UNTIL 245 PM MDT

* AT 154 PM MDT...RADAR INDICATED A SEVERE THUNDERSTORM 16 MILES
  SOUTHWEST OF GARRISON...OR 13 MILES WEST OF DEER LODGE...MOVING
  NORTH AT 35 MPH.

* THE SEVERE THUNDERSTORM WILL BE...
  6 MILES WEST OF GARRISON AT 210 PM MDT

LARGE HAIL IS LIKELY WITH THIS SEVERE THUNDERSTORM. DAMAGING WINDS IN
EXCESS OF 55 MPH ARE POSSIBLE...ALONG WITH FREQUENT LIGHTNING AND
HEAVY RAIN. FOR YOUR PROTECTION...GO INDOORS AND STAY AWAY FROM
WINDOWS. IF YOU ARE CAUGHT OUTSIDE...MOVE TO A WELL PROTECTED AREA.


LAT...LON 4632 11313 4628 11288 4690 11264 4695 11300

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Missoula, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 4, 9:31 AM MDT, 4 hours 23 minutes earlier.

Area forecast discussion, Aug 4, 9:31 AM MDT, 4 hours 23 minutes before
WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
931 AM MDT SAT AUG 4 2001

.SHORT TERM...HAVE UPDATED ZFP AND SFP. MSX RADAR AND SATELLITE
IMAGERY SHOWS SOME SHOWERS/THUNDERSTORMS MOVING INTO SOUTHERN
RAVALLI COUNTY IN THE SOUTHWEST FLOW. CLOUDS MOVING ACROSS NORTHERN
IDAHO AND INTO THE NORTHWEST CORNER OF MONTANA...AHEAD OF THE UPPER
TROUGH MOVING ACROSS WASHINGTON. EXPECT SCATTERED
SHOWERS/THUNDERSTORMS TODAY AS THE TROUGH MOVES ACROSS THE AREA...
ALONG WITH BREEZY WINDS. RIDGE REBUILDS ON SUNDAY WITH A WARMING
TREND. KOLATA

.MSO...NONE.

The office that day

Everything else NWS Missoula, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 4, 1:10 PM MDTSevere Thunderstorm WarningMSODeer Lodge, Silver Bow65 min
Aug 4, 2:29 PM MDTSevere Thunderstorm WarningMSOSilver Bow61 min

Nearby

Severe Thunderstorm Warnings in Montana, 2001Every severe thunderstorm warning 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.