Alert archive / Montana / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 57, NWS Missoula, MT

August 23, 1997Beaverhead County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Aug 23, 1997, 4:03 PM MDT for Beaverhead County, Montana. It was in force for 27 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
Aug 23, 1997, 4:03 PM MDT (22:03 UTC)
Expired
Aug 23, 1997, 4:30 PM MDT
In force
27 min
Issued by
NWS Missoula, MT
Area
Whole counties

County Beaverhead County, MT

The radar

The Pocatello radar (KSFX), 226 km from the middle of the area, began a volume at 22:05 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 12:00Z, 10.1 hours before the alert went out and 313 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 1997-08-23Temperature 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 1997-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 59 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2922 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
59 m²/s²
0-3 km storm-relative helicity
152 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 232204 RRA
SVRMSO
MTC001-232230-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
403 PM MDT SAT AUG 23 1997
 
THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  430 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTHWEST MONTANA
 
   ...NORTHEASTERN BEAVERHEAD COUNTY
 
AT 4PM NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE THUNDERSTORM IN
NORTHEAST BEAVERHEAD COUNTY. THE DILLON AIRPORT REPORTED A WIND GUST OF
53 MPH ASSOCIATED WITH THIS STORM. A SPOTTER REPORTED PEA SIZE HAIL.
THIS STORM IS MOVING NORTHEAST AT 20 MPH. AND WILL MOVE INTO MADISON
COUNTY BY 4:15
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WH,ERE WATER COVERS THE ROAD.
 
HOADLEY

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 Aug 23, 1:52 PM MDT, 2 hours 11 minutes earlier.

Area forecast discussion, Aug 23, 1:52 PM MDT, 2 hours 11 minutes before
WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
150 PM MDT SAT AUG 23 1997

VORT AT NORTHEAST CORNER OF CA LOOKS LESS OF A THREAT TO NORTH
CENTRAL ID TO CAUSE SHOWERS ESPECIALLY SINCE MOISTURE IS INITIALLY
SO LIMITED. NOTHING ON RADARS ATTM AND VISUAL SATELLITE SHOTS SHOW
NOTHING UPSTREAM FROM CWA THAT IS READY TO POP YET. SHORTWAVE AT
38N/128W SHOWING ALOT OF NEGATIVE TILT ATTM AND DONT KNOW THAT WILL
LAST BUT PREFER MUCH SLOWER ETA/NGM PROGRESSION REGARDING IT. MAJOR
DIFFERENCES BETWEEN MODELS OVER THE POSITION OF JET ON SUN. BUT NO
MATTER WHICH WE LOOK AT...MSO NORTHWARD TO CANADIAN BORDER WOULD BE
IN A FAVORABLE QUADRANT FOR LIFTING. NOT ALOT OF INSTABILITY WITH
THIS SYSTEM AND MAY ONLY MENTION ISOLATED THUNDER. SHORTWAVE RIDGE
DEVELOPS SUN NIGHT/MON WHILE MOISTURE AND LIFTING MECHANISMS GET
SHOVED INTO CANADA...GOING BELOW GUIDANCE POPS THEN. TEMP REBOUND
ALSO LOOKS UNDERDONE FOR MON GIVEN THE RISE IN THICKNESS AND 8H
TEMPS ON AVN PLUS BETTER SUNSHINE. WILL BE A MARGINAL DAY FOR LAKE
WIND ADVISORY FOR TOMORROW...WILL PASS THE WORD ON. GV

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

LIB .. 057/073 044/080 ... 354722
FCA WB 055/073 045/080 047 353721
POL .. 058/074 050/078 ... 353611
MSO EB 056/076 050/083 051 353510
HMM .. 055/078 049/085 ... 353410
BTM .. 052/074 043/079 ... 352410
S80 .. 057/078 048/083 ... 352310
P69 .. 059/080 051/085 ... 352310
SMN .. 050/080 050/083 ... 351210

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.