Alert archive / Montana / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 41, NWS Missoula, MT

July 30, 1998Mineral County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Jul 30, 1998, 2:09 PM MDT for Mineral County, Montana. It was in force for 46 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 30, 1998, 2:09 PM MDT (20:09 UTC)
Expired
Jul 30, 1998, 2:55 PM MDT
In force
46 min
Issued by
NWS Missoula, MT
Area
Whole counties

County Mineral County, MT

The radar

The Missoula radar (KMSX), 78 km from the middle of the area, began a volume at 20:13 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

Spokane, WA (KOTX), launched 12:00Z, 8.2 hours before the alert went out and 122 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, Spokane, WA at 12:00Z on 1998-07-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 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, Spokane, WA at 12:00Z on 1998-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 50 square meters per square second.1939Sfc1 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
8 J/kg
Mixed-layer CIN
-342 J/kg
Mixed-layer LCL
1869 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
50 m²/s²
0-3 km storm-relative helicity
43 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.

167 
WUUS1 KMSO 302012 RRA
SVRMSO
MTC061-302055-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
209 PM MDT THU JUL 30 1998

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN MINERAL COUNTY IN WEST CENTRAL MONTANA

* UNTIL 255 PM MDT

* AT 205 PM MDT...SEVERE THUNDERSTORM INDICATED 5 MILES SOUTHEAST
  OF LOOKOUT PASS...BY NATIONAL WEATHER SERVICE DOPPLER RADAR...
  MOVING NORTHWEST AT 10 MPH.

* SEVERE THUNDERSTORM WILL BE NEAR...
  INTERSTATE 90 NEAR LOOKOUT PASS AT 230 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.

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 30, 9:00 AM MDT, 5 hours 9 minutes earlier.

Area forecast discussion, Jul 30, 9:00 AM MDT, 5 hours 9 minutes before
WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
900 AM MDT THU JUL 30 1998

NO CHANGES TO MT ZONES. 03Z ETA RUN NICELY SHOWS EXTENSION OF VORT
LOBE ROTATING NORTHWARD FROM UPPER LOW ALONG NORTHERN CALIF COAST.
SHORTWAVE NOTED IN S-CENTRAL IDA AND LAYERED MOISTURE BAND CENTRAL
IDA...SYSTEM MOVES ACROSS FORECAST AREA THIS AFTERNOON IN GOOD TIMING
OF AFTERNOON HEATING. NEARBY RAOBS SHOW LARGE CAPES TODAY AFTER
WARMING OF LOWEST 100 MB. WEAK SHEAR AVAILABLE FOR SEVERE STORMS BUT
STRONG LIFT ASSOCIATED WITH SHORTWAVE AND SLOW CELL MOVEMENT SHOULD
RESULT IN GOOD PRECIP MAKERS AND POTENTIAL HAIL. STRONGER DYNAMICS
TODAY NEAR UPPER LOW ACROSS EASTERN ORE...BUT LEFTOVER CONVECTION MAY
HOLD TOGETHER LATE TONIGHT AS IT MOVES OVER CWA. UPPER TROUGH MOVES
INLAND FRIDAY AND WILL KEEP ACTIVE SHOWER/T-STORM PATTERN W OF DIVIDE
WITH BETTER CHANCE OF SEVERE E OF DIVIDE. MORNING CLOUDS AND SHOWERS
ACROSS IDA ZONES MAY HAMPER MAX TEMPS SLIGHTLY...WILL SEND CHANGES.
BOLDT

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

LIB .. 087/060 086/... ... 28653
FCA TW 085/059 084/057 080 28553
POL .. 084/062 083/... ... 28553
MSO TW 086/059 084/057 082 28554
HMM .. 088/060 086/... ... 28554
BTM .. 081/054 080/... ... 28555
S80 .. 086/058 089/... ... 28653
P69 .. 093/062 093/... ... 28653
SMN .. 090/053 088/... ... 28553

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.