Alert archive / Montana / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 64, NWS Missoula, MT

September 5, 1997Missoula County, Powell County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Sep 5, 1997, 8:02 PM MDT for Missoula County, Powell County, Montana. It was in force for 58 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: Sep 5, 1997, 8:02 PM MDT (02:02 UTC)
Expired: Sep 5, 1997, 9:00 PM MDT
In force: 58 min
Issued by: NWS Missoula, MT
Area: Whole counties

Counties Missoula County, MT, Powell County, MT

The radar

The Missoula radar (KMSX), 43 km from the middle of the area, began a volume at 02:04 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, 2.0 hours before the alert went out and 221 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 35 J/kg
Mixed-layer CIN: -24 J/kg
Mixed-layer LCL: 3054 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: -9 m²/s²
0-3 km storm-relative helicity: 37 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 KMSO 060204 RRA
SVRMSO
MTC053-063-077-060300-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
802 PM MDT FRI SEP 5 1997
 
THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  900 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN NORTHWEST MONTANA
 
   ...LINCOLN COUNTY
 
IN WEST CENTRAL MONTANA
 
   ...EASTERN MISSOULA COUNTY...NORTHERN POWELL COUNTY
 
AT 750 PM MDT...A SEVERE THUNDERSTORM WAS LOCATED...7 MILES NORTHWEST
OF HERON ALONG THE IDAHO MONTANA BORDER AND WILL APPROACH LIBBY AT 830
PM MDT. ANOTHER SEVERE STORM WAS LOCATED 17 MILES EAST OF LIBBY MOVING
TO THE NORTH AT 25 MPH. ANOTHER SEVERE THUNDERSTORM WAS OVER EASTERN
MISSOULA COUNTY... 4 MILES WEST OF SEELEY LAKE. THIS STORM WILL MOVE
INTO NORTHERN POWELL COUNTY BY 830 PM MDT. HAIL OF ONE INCH OR GREATER
MAY BE ASSOCIATED WITH THESE STORMS.
 
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A
STRONG BUILDING.  DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.
STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

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.

NWS Missoula, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 5, 1:45 PM MDT, 6 hours 17 minutes earlier.

Area forecast discussion, Sep 5, 1:45 PM MDT, 6 hours 17 minutes before

WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
145 PM MDT FRI SEP 5 1997

MODELS INITIALIZED POORLY WITH ONLY THE ETA HINTING AT THE VORTS TO
THE SOUTH...ONE IN SOUTH CENTRAL OR AND THE OTHER OVER SOUTHERN ID.
BOTH VORTS TRACKING TO THE NORTHEAST ATTM. BASED FCST ON ETA BECAUSE
OF VORT POSITIONS AND ITS MOISTURE PROG SEEMS THE MORE REASONABLE.
PANHANDLE/NW AND WEST CENTRAL MT FAVORED AREAS FOR SIG WX THIS
AFTERNOON/EVENING GIVEN CAPE...LIS AND CON/DIV COUPLET. HOWEVER...
ID VORT SEEMS THE MORE ACTIVE AS SOME CONVECTION FIRING OVER SOUTH
CENTRAL ID ATTM. UPPER LEVEL DISCONTINUITY SEEN ON WV PICS MOVING
THRU EASTERN WA. EXPECT THIS FEATURE AND SURFACE TROF TO BE EDVD
AFTER MIDNIGHT. ACTIVITY TODAY SHOULD BE HIGH BASED WITH GUSTY WINDS
ACCOMPANYING TSTMS. ANALYSIS PAST 24 HRS SHOWS WEST COAST H5 TROF
FILLING AS ADVERTISED BY LAST SEVERAL MODEL RUNS. TROF ROTATES INTO
SASK WITH SHORTWAVE RIDGING OVER NORTHERN ROCKIES SATURDAY
NIGHT/SUNDAY. SW FLOW ALOFT INCREASING ON SUNDAY AHEAD OF NEXT TROF.
AVN HINTING AT S/WV MOVING INTO SW MT BY AFTERNOON. FOSS

...FORECASTS BELOW ARE PRELIMINARY AND SUBJECT TO CHANGE...

LIB .. 050/072 042/072 ... 315211
FCA EB 048/072 042/072 043 314211
POL .. 054/075 050/075 ... 313101
MSO BA 050/077 045/077 043 314102
HMM .. 048/079 042/079 ... 313102
BTM .. 046/075 042/078 ... 313202
S80 .. 049/075 054/078 ... 313101
P69 .. 052/077 054/080 ... 314101
SMN .. 047/075 044/080 ... 313102

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 5, 6:37 PM MDT	Severe Thunderstorm Warning	MSO	Mineral, Missoula	68 min
Sep 5, 7:13 PM MDT	Severe Thunderstorm Warning	MSO	Flathead	62 min
Sep 5, 8:02 PM MDT	Severe Thunderstorm Warning	MSO	Lincoln	58 min
Sep 6, 6:48 AM MDT	Severe Thunderstorm Warning	MSO	Missoula	27 min

Nearby

Severe Thunderstorm Warnings in Montana, 1997 Every 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.