Alert archive / Montana / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 16, NWS Great Falls, MT

June 6, 1997Lewis and Clark County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jun 6, 1997, 2:55 PM MDT for Lewis and Clark County, Montana. It was in force for 50 min. 3 reports 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
Jun 6, 1997, 2:55 PM MDT (20:55 UTC)
Expired
Jun 6, 1997, 3:45 PM MDT
In force
50 min
Issued by
NWS Great Falls, MT
Area
Whole counties

County Lewis and Clark County, MT

The radar

The Great Falls radar (KTFX), 85 km from the middle of the area, began a volume at 20:56 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.

What was reported inside it

TimeReportWhereRemark
Jun 6, 3:23 PM MDTHail 1Helena, MT
Jun 6, 3:30 PM MDTHail 1.25Helena Arpt, MT
Jun 6, 3:35 PM MDTHail 3Helena, 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, 8.9 hours before the alert went out and 140 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 1997-06-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 1997-06-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 43 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
986 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
168 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 062055
SVRGTF
MTC049-062145-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
255 PM MDT FRI JUN 6 1997
 
THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 345 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTHWEST MONTANA
 
   ...SOUTHERN LEWIS AND CLARK COUNTY
 
AT 255 PM...GREAT FALLS RADAR INDICATED A SEVERE THUNDERSTORM 25 MILES
SOUTH|WEST OF HELENA. THIS STORM WAS MOVING TOWARDS THE NORTHEAST AT 35
MPH AND WILL MOVE INTO HELENA BY 330 PM. LARGE DAMAGING HAIL AND HEAVY
RAIN ARE LIKELY WITH THIS STORM.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 5, 6:34 PM MDTSevere Thunderstorm WarningTFXBroadwater41 min
Jun 6, 3:45 PM MDTSevere Thunderstorm WarningTFXLewis and Clark45 min
Jun 6, 4:03 PM MDTSevere Thunderstorm WarningTFXCascade57 min
Jun 6, 4:19 PM MDTSevere Thunderstorm WarningTFXChouteau, Judith Basin56 min
Jun 6, 4:38 PM MDTSevere Thunderstorm WarningTFXCascade67 min
Jun 6, 5:15 PM MDTSevere Thunderstorm WarningTFXBlaine, Chouteau, Fergus60 min
Jun 6, 5:31 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau, Judith Basin, Meagher59 min
Jun 6, 5:52 PM MDTSevere Thunderstorm WarningTFXYellowstone68 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; radar from the NEXRAD Level II archive.