Alert archive / Montana / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 80, NWS Great Falls, MT

September 15, 1997Cascade County, Chouteau County, Judith Basin County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Sep 15, 1997, 1:42 PM MDT for Cascade County, Chouteau County, Judith Basin County, Montana. It was in force for 63 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Sep 15, 1997, 1:42 PM MDT (19:42 UTC)
Expired
Sep 15, 1997, 2:45 PM MDT
In force
63 min
Issued by
NWS Great Falls, MT
Area
Whole counties

Counties Cascade County, MT, Chouteau County, MT, Judith Basin County, MT

What was reported inside it

TimeReportWhereRemark
Sep 15, 2:30 PM MDTHail 0.75Eden, MT

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 7.7 hours before the alert went out and 8 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 1997-09-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 54 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 1997-09-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 156 square meters per square second.1939587897Sfc1 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
54 J/kg
Mixed-layer CIN
-492 J/kg
Mixed-layer LCL
1231 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
156 m²/s²
0-3 km storm-relative helicity
181 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 151945
SVRGTF
MTC045-013-015-152045-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
142 PM MDT MON SEP 15 1997
 
THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  245 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN CENTRAL MONTANA
 
   ...NORTHWESTERN JUDITH BASIN COUNTY
 
IN NORTH MONTANA
 
   ...EAST CENTRAL CASCADE COUNTY
 
IN NORTH CENTRAL MONTANA
 
   ...SOUTHWESTERN CHOUTEAU COUNTY
 
DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM IN EASTERN CASCADE COUNTY.
THIS STORM WAS MOVING TOWARD THE NORTHEAST AT 45 TO 50 MPH AND WILL MOVE
ACROSS NORTHWEST JUDITH BASIN COUNTY AND INT&O SOUTHWEST CHOUTEAU COUNTY
BY 230 PM THIS AFTERNOON. REPORTS OF 3/4 INCH HAIL HAVE BEEN REPORTED
WITH THIS STORM ALONG WITH WIND GUSTS IN EXCESS OF 60 MPH. BRIEF HEAVY
RAIN HAS ALSO BEEN REPORTED.
 
&

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.

In the hours before

Special weather statement, Sep 15, 1:26 PM MDT, 16 minutes before
MTZ014-151930-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
120 PM MDT MON SEP 15 1997

...SEVERE THUNDERSTORM WARNING FOR SOUTHERN LEWIS AND CLARK COUNTY HAS
   BEEN ALLOWED TO EXPIRE...

...SEVERE THUNDERSTORM WARNING CONTINUES FOR NORTHERN CASCADE COUNTY
   UNTIL 145 PM MDT...

THE SEVERE THUNDERSTORM THAT DEVELOPED OVER SOUTHERN LEWIS AND CLARK HAS
DIMINISHED IN INTENSITY AND HAS MOVED EAST INTO NORTHERN BROADWATER
COUNTY. REPORTS OF WIND GUSTS TO 60 MPH AND HAIL THREE-QUARTER INCH IN
DIAMETER WERE REPORTED IN THE HELENA AREA.

A SEVERE THUNDERSTORM OVER NORTHERN CASCADE COUNTY CONTINUES TO MOVE
NORTHEAST AT 40 MPH. STRONG GUSTY WINDS IN EXCESS OF 55 MPH...HEAVY
RAIN AND HAIL HAVE BEEN REPORTED WITH THIS STORM.
&

&
Special weather statement, Sep 15, 1:27 PM MDT, 15 minutes before
MTZ014-151930-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
120 PM MDT MON SEP 15 1997

...SEVERE THUNDERSTORM WARNING FOR SOUTHERN LEWIS AND CLARK COUNTY HAS
   BEEN ALLOWED TO EXPIRE...

...SEVERE THUNDERSTORM WARNING CONTINUES FOR NORTHERN CASCADE COUNTY
   UNTIL 145 PM MDT...

THE SEVERE THUNDERSTORM THAT DEVELOPED OVER SOUTHERN LEWIS AND CLARK HAS
DIMINISHED IN INTENSITY AND HAS MOVED EAST INTO NORTHERN BROADWATER
COUNTY. REPORTS OF WIND GUSTS TO 60 MPH AND HAIL THREE-QUARTER INCH IN
DIAMETER WERE REPORTED IN THE HELENA AREA.

A SEVERE THUNDERSTORM OVER NORTHERN CASCADE COUNTY CONTINUES TO MOVE
NORTHEAST AT 40 MPH. STRONG GUSTY WINDS IN EXCESS OF 55 MPH...HEAVY
RAIN AND HAIL HAVE BEEN REPORTED WITH THIS STORM.
&

&

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 15, 11:46 AM MDTSevere Thunderstorm WarningTFXLewis and Clark44 min
Sep 15, 12:27 PM MDTSevere Thunderstorm WarningTFXLewis and Clark48 min
Sep 15, 12:36 PM MDTSevere Thunderstorm WarningTFXCascade, Lewis and Clark54 min
Sep 15, 1:04 PM MDTSevere Thunderstorm WarningTFXCascade41 min
Sep 15, 2:42 PM MDTSevere Thunderstorm WarningTFXBlaine, Chouteau, Hill63 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.