Alert archive / Montana / Tornado Warnings in 1991

Tornado Warning 3, NWS Great Falls, MT

June 25, 1991Cascade County, Chouteau County, Montana

NWS Great Falls, MT issued this tornado warning at Jun 25, 1991, 11:16 AM MDT for Cascade County, Chouteau County, Montana. It was in force for 29 min.

The area

The counties it named.

The facts

Issued
Jun 25, 1991, 11:16 AM MDT (17:16 UTC)
Expired
Jun 25, 1991, 11:45 AM MDT
In force
29 min
Issued by
NWS Great Falls, MT
Area
Whole counties

Counties Cascade County, MT, Chouteau County, MT

The nearest sounding before it

Great Falls, MT (KGTF), launched 12:00Z, 5.3 hours before the alert went out and 33 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 1991-06-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 25 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 1991-06-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 11 square meters per square second.193958Sfc1 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
25 J/kg
Mixed-layer CIN
-33 J/kg
Mixed-layer LCL
832 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
67 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 
TTAA00 KGTF 251717
TORGTF
MTC013-015-251745-
 
BULLETIN - EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
1116 AM MDT TUE JUN 25 1991
 
THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A
TORNADO WARNING EFFECTIVE UNTIL 1145 AM MDT
FOR PEOPLE IN THE FOLLOWING LOCATION...S...
 
IN NORTH CENTRAL MONTANA
 
   ...NORTHEASTERN CASCADE COUNTY...WESTERN CHOUTEAU COUNTY
 
A FUNNEL CLOUD HAS BEEN REPORTED 10 MILES NE OF GREAT FALLS ALONG BOOT
LEGGER TRAIL. THE STORM ASSOCIATED WITH THIS FUNNEL CLOUD IS MOVING
NORTHEAST INTO WESTERN CHOTEAU COUNTY.
 
 
IF YOU ARE IN THE PATH OF A TORNADO...THE SAFEST PLACE IS A
BASEMENT.  GET UNDER A WORKBENCH OR PIECE OF STURDY FURNITURE.
IF NO BASdEMENT IS AVAILABLE...SEEK SHELTER IN AN INTERIOR ROOM
SUCH AS A CLOSET ON THE LOWEST FLOOR.  USE BLANKETS...PILLOWS...
OR CUSHIONS TO COVER YOUR BODY.  AVOID WINDOWS.

What forecasters said that day

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

In the hours before

Special weather statement, Jun 25, 7:39 AM MDT, 3 hours 37 minutes before
MTZ006-251500-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
736 AM MDT TUE JUN 25 1991

...STRONG THUNDERSTORM IN SOUTHEAST FERGUS COUNTY...

BILLINGS RADAR AND SATELLITE PICTURES SHOW A STRONG THUNDERSTORM
LOCATED IN SOUTHEAST FERGUS COUNTY MOVING RAPIDLY NORTHEAST AT ABOUT
40 MPH. THIS STORM WILL MOVE INTO PETROLEUM COUNTY BY AROUND 8 AM MDT.

THE RADAR INDICATES POSSIBLE HAIL WITH THIS SYSTEM AND LOCALLY HEAVY
RAINS ARE LgIKELY ALONG WITH BRIEF GUSTY WINDS.

RESIDENTS IN SOUTHEAST FERGUS AND WESTERN PETROLEUM COUNTIES ARE
URGED TO PAY CLOSE ATTENTION TO THIS STORM AND BE PREPARED TO MOVE
TO A PLACE OF SAFETY IF ADVERSE CONDITIONS OCCUR.
END...

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 25, 3:31 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau59 min
Jun 25, 4:01 PM MDTTornado WarningTFXCascade, Chouteau59 min

Nearby

Tornado Warnings in Montana, 1991Every tornado warning in 1991Tornadoes in 1991

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.