Alert archive / Montana / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 3, NWS Great Falls, MT

May 31, 1997Pondera County, Teton County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at May 31, 1997, 8:41 PM MDT for Pondera County, Teton County, Montana. It was in force for 34 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
May 31, 1997, 8:41 PM MDT (02:41 UTC)
Expired
May 31, 1997, 9:15 PM MDT
In force
34 min
Issued by
NWS Great Falls, MT
Area
Whole counties

Counties Pondera County, MT, Teton County, MT

The radar

The Great Falls radar (KTFX), 90 km from the middle of the area, began a volume at 02:41 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 31, 4:15 PM MDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 2.7 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 1997-06-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 133 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 1997-06-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 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
133 J/kg
Mixed-layer CIN
-72 J/kg
Mixed-layer LCL
1740 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
130 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KGTF 010244
SVRGTF
MTC073-099-010315-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING!!!
NATIONAL WEATHER SERVICE GREAT FALLS MT
841 PM MDT SAT MAY 31 1997
 
      ***
THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  915 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN NORTH MONTANA
 
   ...EASTERN PONDERA COUNTY...EASTERN TETON COUNTY
 
AT 235 PM...A SEVERE THUNDERSTORM WAS OVER EASTERN PONDERA AND EASTERN
TOOLE COUNTY. THIS THUNDERSTORM WAS MOVING TOWARDS THE EAST AT 35 MPH. A
SPOTTER IN VALIER REPORTED A ROOF TAKEN OFF A TRAILER HOUSE IN THE TOWN
OF VALIER. STRONG DAMAGING WINDS TO 65 MPH AND HEAVY RAIN ARE LIKELY
WITH THIS THUNDERSTORM.
         &

The office that day

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

IssuedProductOfficeCountiesLasted
May 31, 8:18 PM MDTSevere Thunderstorm WarningTFXGlacier, Toole42 min
May 31, 9:02 PM MDTSevere Thunderstorm WarningTFXChouteau, Liberty43 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.