Alert archive / Montana / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 45, NWS Missoula, MT

August 7, 1998Deer Lodge County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Aug 7, 1998, 2:33 PM MDT for Deer Lodge County, Montana. It was in force for 47 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
Aug 7, 1998, 2:33 PM MDT (20:33 UTC)
Expired
Aug 7, 1998, 3:20 PM MDT
In force
47 min
Issued by
NWS Missoula, MT
Area
Whole counties

County Deer Lodge County, MT

What was reported inside it

TimeReportWhereRemark
Aug 7, 3:20 PM MDTHail 1.75Anaconda, 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, 8.6 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 1998-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 70 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 1998-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
70 J/kg
Mixed-layer CIN
-254 J/kg
Mixed-layer LCL
1445 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
153 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.

813 
WUUS1 KMSO 072037 RRA
SVRMSO
MTC023-072120-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
233 PM MDT FRI AUG 7 1998

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN DEER LODGE COUNTY IN WEST CENTRAL MONTANA

* UNTIL 320 PM MDT

* AT 225 PM MDT...SEVERE THUNDERSTORM INDICATED 10 MILES WEST OF
  ANACONDA...BY NATIONAL WEATHER SERVICE DOPPLER RADAR...MOVING
  NORTHEAST AT 25 MPH.

* SEVERE THUNDERSTORM WILL BE NEAR...
  STATE ROUTE 1 AT 235 PM MDT
  INTERSTATE 90...5 MILES NORTH OF WARM SPRINGS AT 300 PM MDT


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 DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

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 7, 2:30 PM MDT, 3 minutes earlier.

Area forecast discussion, Aug 7, 2:30 PM MDT, 3 minutes before
WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
230 PM MDT FRI AUG 7 1998

VORT CENTER CRUISING OVER CENTRAL WASHINGTON IDENTIFIED WELL BY ETA
ALONG WITH SURFACE CONVERGENCE ZONE OVER SOUTHWEST MONTANA WHERE
ACTIVITY STILL GENERATING WHILE SLIPPING SOUTHEASTWARD. CONVECTIVE
INSTABILITIES STILL REMAIN FAVORABLE OVER THE ENTIRE CWA FOR THIS
AFTERNOON AND EVENING ISOLATED ACTIVITY...MORE SCATTERED SOUTH. BY
SATURDAY MORNING...HEIGHTS START TO RISE REDEFINING AND BUILDING
UPPER RIDGE OVER THE FORECAST AREA. ETA SUGGEST BEST INSTABILITY TO
SHIFT EAST OF THE DIVIDE WITH DRIER AIR ADVECTING OVER CWA.
TEMPERATURES TREND UPWARD FOR SUNDAY AS THERMAL TROF REDEVELOPS OVER
WESTERN IDAHO.

STOLL

LIB .. 047/087 048/088 ... 332000
FCA UU 048/088 049/089 051 332000
POL .. 049/086 050/087 ... 332000
MSO UU 053/088 051/091 053 332000
HMM .. 055/090 054/093 ... 332000
BTM .. 048/088 047/091 ... 332100
S80 .. 053/089 054/090 ... 331000
P69 .. 055/091 054/091 ... 331000
SMN .. 049/089 048/090 ... 331000

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 12:15 AM MDTSevere Thunderstorm WarningMSOMissoula, Ravalli60 min
Aug 7, 3:43 PM MDTSevere Thunderstorm WarningMSOPowell47 min
Aug 7, 4:31 PM MDTSevere Thunderstorm WarningMSOPowell34 min

Nearby

Severe Thunderstorm Warnings in Montana, 1998Every severe thunderstorm warning in 1998

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.