Alert archive / Montana / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 79, NWS Great Falls, MT

August 4, 2001Beaverhead County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Aug 4, 2001, 1:17 PM MDT for Beaverhead County, Montana. It was in force for 28 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, 1:17 PM MDT (19:17 UTC)
Expired
Aug 4, 2001, 1:45 PM MDT
In force
28 min
Issued by
NWS Great Falls, MT
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Beaverhead County, MT

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 7.3 hours before the alert went out and 289 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.

074 
WUUS55 KTFX 041917
SVRGTF
MTC001-041945-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
117 PM MDT SAT AUG 4 2001

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL BEAVERHEAD COUNTY IN SOUTHWEST MONTANA

* UNTIL 145 PM MDT

* AT 100 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  A SEVERE THUNDERSTORM OVER NORTHWESTERN BEAVERHEAD                 
  COUNTY....MOVING NORTHEAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
RURAL NORTHERN BEAVERHEAD COUNTY AT 130 PM MDT

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN GREAT FALLS.

LAT...LON 4550 11339 4537 11320 4562 11281 4578 11303

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 Great Falls, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 4, 8:53 AM MDT, 4 hours 24 minutes earlier.

Area forecast discussion, Aug 4, 8:53 AM MDT, 4 hours 24 minutes before
SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
853 AM MDT SAT AUG 4 2001

WILL UPDATE ZONES THIS MORNING TO INCREASE MAX TEMPERATURES F0R THIS
AFTERNOON AND REFLECT THE MOSTLY CLEAR CONDITIONS THIS MORNING.
FIRST SHORT WAVE WENT CWA THROUGH LAST NIGHT...THE 2ND NOW MOVING
THROUGH EASTERN WASHINGTON.  WATER VAPOR IMAGERY SHOWS DRY SLOT
THROUGH WRN 3RD MONTANA...RESULTING IN MOSTLY CLEAR SKIES...ALLOWING
GOOD INSOLATION AHEAD OF NEXT TROUGH.  SFC ANALYSIS SUGGESTS COLD
FRONT NEAR CTB THEN EXTENDING SW ACROSS THE DIVIDE. DON NOT EXPECT
THIS FRONT TO ACTIVELY ADVANCE UNTIL MUCH LATER TODAY. NEW ETA
PREDICTS THAT THE STRONGEST DYNAMICS WILL AFFECT THE CWA LATE THIS
AFTERNOON AND EVENING. GREATEST THREAT WILL BE THE WINDS WITH HIGH
BASED TSTMS.  WE HAVE ISSUED RED FLAG WARNING FOR LOW RH, DRY TSTMS
AND ASSOCIATED WINDS. MIELKE

GTF EU 095/057 087/055 092 14330
CTB EU 085/052 084/050 088 14330
HLN EU 095/052 089/050 091 14330
BZN EU 094/052 090/050 092 14330
WEY EU 087/044 084/042 088 14330
DLN EU 088/048 086/046 088 14320
HVR EU 099/060 090/058 094 14230
LWT EU 097/055 088/053 090 14230

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 1:28 PM MDTSevere Thunderstorm WarningTFXCascade, Lewis and Clark47 min
Aug 4, 2:15 PM MDTSevere Thunderstorm WarningTFXCascade60 min
Aug 4, 2:18 PM MDTSevere Thunderstorm WarningTFXJefferson27 min
Aug 4, 3:12 PM MDTSevere Thunderstorm WarningTFXLewis and Clark63 min
Aug 4, 3:39 PM MDTSevere Thunderstorm WarningTFXJudith Basin66 min
Aug 4, 3:49 PM MDTSevere Thunderstorm WarningTFXCascade26 min
Aug 4, 3:59 PM MDTSevere Thunderstorm WarningTFXBroadwater31 min
Aug 4, 4:00 PM MDTSevere Thunderstorm WarningTFXMeagher30 min
Aug 4, 4:09 PM MDTSevere Thunderstorm WarningTFXCascade51 min
Aug 4, 4:43 PM MDTSevere Thunderstorm WarningTFXCascade32 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.