Alert archive / Montana / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 18, NWS Missoula, MT

July 19, 1997Deer Lodge County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Jul 19, 1997, 9:34 AM MDT for Deer Lodge County, Montana. It was in force for 56 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
Jul 19, 1997, 9:34 AM MDT (15:34 UTC)
Expired
Jul 19, 1997, 10:30 AM MDT
In force
56 min
Issued by
NWS Missoula, MT
Area
Whole counties

County Deer Lodge County, MT

The radar

The Missoula radar (KMSX), 130 km from the middle of the area, began a volume at 15:35 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, 3.6 hours before the alert went out and 244 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 1997-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 122 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 1997-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 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
122 J/kg
Mixed-layer CIN
-92 J/kg
Mixed-layer LCL
1225 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
51 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 191534 RRA
SVRMSO
MTC023-191630-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
934 AM MDT SAT JUL 19 1997
 
THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1030 AM MDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTHWEST MONTANA
 
   ...DEER LODGE COUNTY
 
AT 930 AM MDT MISSOULA RADAR INDICATED A SEVERE THUNDERSTORM MOVING INTO
DEER LODGE COUNTY 10 MILES SOUTH OF ANACONDA. THE STORM IS MOVING NORTH
AT 20 MPH...AND WILL APPROACH ANACONDA AROUND 10 AM MDT.
 
THIS STORM HAS PRODUCED HAIL IN EXCESS OF ONE-INCH DIAMETER...FREQUENT
LIGHTNING...AND HEAVY RAIN SHOWERS.
 
FOR YOUR PROTECTION MOVE TOP AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.
 
WHITMORE
 
&

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 Jul 19, 9:15 AM MDT, 19 minutes earlier.

Area forecast discussion, Jul 19, 9:15 AM MDT, 19 minutes before
WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
915 AM MDT SAT JUL 19 1997

THUNDERSTORM ACTIVITY CONTINUING...MAINLY OVER SOUTHWEST
MONTANA...BUT PLENTY OF SHOWERS ELSEWHERE AS VORT LOBES PINWHEEL
AROUND LOW.  NO NEW MODELS TO LOOK AT...HOWEVER STILL HAVE SOME
CHANGES IN MIND.  RADAR AND SATELLITE SHOWING BAND OF MOISTURE MAKING
IT UP INTO NORTHWEST MONTANA.  BELIEVE LATER BANDS SHOULD ALSO
PROGRESS INTO THE NORTH.  SO WILL BUMP UP POPS FIRST PERIOD.
MOISTURE ALSO TRACKING INTO NORTH CENTRAL IDAHO.  LATER BANDS MAY
HAVE MORE DIFFICULTY MOVING THAT FAR WESTWARD AS THE UPPER LOW DRIFTS
EAST...BUT POPS COULD STILL BE RAISED.  TEMPS LOOK REASONABLE.  WORK
ZONES DO CONTAIN CHANGES.             WHITMORE

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

LIB .. 082/057 084/... ... 34532
FCA WE 081/056 080/054 082 34643
POL .. 081/057 085/... ... 34753
MSO WE 078/056 082/055 085 34874
HMM .. 077/055 085/... ... 34864
BTM .. 070/050 073/... ... 34975
S80 .. 075/055 084/... ... 34632
P69 .. 078/058 081/... ... 34742
SMN .. 073/053 082/... ... 34642

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 19, 8:30 AM MDTSevere Thunderstorm WarningMSOBeaverhead, Silver Bow60 min
Jul 19, 12:00 PM MDTSevere Thunderstorm WarningMSOPowell45 min
Jul 19, 2:19 PM MDTFlash Flood WarningMSOBeaverhead56 min
Jul 19, 2:19 PM MDTSevere Thunderstorm WarningMSOBeaverhead56 min
Jul 19, 3:06 PM MDTTornado WarningMSOBeaverhead69 min
Jul 19, 4:00 PM MDTSevere Thunderstorm WarningMSOSilver Bow60 min
Jul 19, 5:25 PM MDTSevere Thunderstorm WarningMSOPowell50 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.