Alert archive / Montana / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 61, NWS Great Falls, MT

August 7, 1997Liberty County, Pondera County, Toole County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Aug 7, 1997, 6:09 PM MDT for Liberty County, Pondera County, Toole County, Montana. It was in force for 66 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 7, 1997, 6:09 PM MDT (00:09 UTC)
Expired
Aug 7, 1997, 7:15 PM MDT
In force
66 min
Issued by
NWS Great Falls, MT
Area
Whole counties

Counties Liberty County, MT, Pondera County, MT, Toole County, MT

The radar

The Great Falls radar (KTFX), 115 km from the middle of the area, began a volume at 00:09 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.

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 0.2 hours before the alert went out and 138 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 1997-08-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 655 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 1997-08-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -8 square meters per square second.1939Sfc1 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
655 J/kg
Mixed-layer CIN
-41 J/kg
Mixed-layer LCL
2423 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
-8 m²/s²
0-3 km storm-relative helicity
72 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.

886 
WUUS1 KGTF 080012 RRA
SVRGTF
MTC073-099-101-051-080115-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
609 PM MDT THU AUG 7 1997
 
THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  715 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN NORTH MONTANA
 
   ...EASTERN PONDERA COUNTY...EASTERN TETON COUNTY
   ...SOUTHERN TOOLE COUNTY...SOUTHERN LIBERTY COUNTY
 
AT 605 PM...RADAR INDICATED A SEVERE THUNDERSTORMS 20 MILES NORTHEAST OF
CONRAD...10 MILES SOUTHWEST OF CONRAD AND 15 MILES WEST OF CHOTEAU IN
CENTRAL TETON COUNTY. THESE STORMS WERE MOVING EAST AT 30 MPH.
 
THE STORM NORTHEAST OF CONRAD WILL AFFECT THE TIBER DAM AREA WITHIN THE
NEXT HOUR. THE STORM SOUTHWEST OF CONRAD WILL BE MOVING THROUGH EASTERN
PONDERA COUNTY.  THE STORM OVER TETON COUNTY WILL BE MOVING THROUGH
EASTERN TETON COUNTY OVER THE NEXT HOUR.
 
LARGE HAIL...DAMAGING WIND...STRONG WIND AND DANGEROUS LIGHTNING ARE
LIKELY WITH THESE STORMS.
 
 
 
 
&

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 6:09 PM MDTSevere Thunderstorm WarningTFXTeton66 min
Aug 7, 6:42 PM MDTSevere Thunderstorm WarningTFXLewis and Clark63 min
Aug 7, 6:57 PM MDTSevere Thunderstorm WarningTFXMeagher63 min
Aug 7, 7:38 PM MDTSevere Thunderstorm WarningTFXTeton52 min
Aug 7, 9:00 PM MDTSevere Thunderstorm WarningTFXCascade60 min

Nearby

Severe Thunderstorm Warnings in Montana, 1997Every severe thunderstorm warning in 1997

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.