Alert archive / Idaho / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 42, NWS Missoula, MT

July 30, 1998Lemhi County, Idaho

NWS Missoula, MT issued this severe thunderstorm warning at Jul 30, 1998, 4:35 PM MDT for Lemhi County, Idaho. It was in force for 40 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, 4:35 PM MDT (22:35 UTC)
Expired
Jul 30, 1998, 5:15 PM MDT
In force
40 min
Issued by
NWS Missoula, MT
Area
Whole counties

County Lemhi County, ID

The radar

The Pocatello radar (KSFX), 227 km from the middle of the area, began a volume at 22:37 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

Boise Airport, ID (KBOI), launched 12:00Z, 10.6 hours before the alert went out and 236 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, Boise Airport, ID at 12:00Z on 1998-07-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 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, Boise Airport, ID at 12:00Z on 1998-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -14 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
5 J/kg
Mixed-layer CIN
-408 J/kg
Mixed-layer LCL
2078 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
-14 m²/s²
0-3 km storm-relative helicity
57 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 302237 RRA
SVRMSO
IDC059-302315-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
435 PM MDT (335 PM PDT) THU JUL 30 1998

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN LEMHI COUNTY IN EAST CENTRAL IDAHO

* UNTIL 515 PM MDT

* AT 435 PM MDT...SEVERE THUNDERSTORM INDICATED 8 MILES SOUTH OF
  SALMON...BY NATIONAL WEATHER SERVICE DOPPLER RADAR...MOVING
  NORTH AT 15 MPH.

* SEVERE THUNDERSTORM WILL BE NEAR...
  SALMON AT 445 PM MDT


DESTRUCTIVE HAIL...DAMAGING WINDS...DEADLY LIGHTNING...AND VERY
HEAVY RAIN ARE ALL LIKELY WITH THIS STORM. FOR YOUR PROTECTION...
MOVE INSIDE A STRONG BUILDING...AND STAY A0WAY FROM WINDOWS. DO NOT
DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

FOSS/BELTZ

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, 2:30 PM MDT, 2 hours 5 minutes earlier.

Area forecast discussion, Jul 30, 2:30 PM MDT, 2 hours 5 minutes before
WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
230 PM MDT THU JUL 30 1998

WILL FOLLOW ETA MODEL SINCE IT INITIALIZED WELL AND JET SOUTH SIDE OF
TROUGH BUT LITTLE DIFFERENCE SINCE ALL SHOW TROUGH MOVING INLAND NEXT
48 HOURS. FIRST SHORTWAVE OVER IDA LIFTING NORTH AND BRINGING BAND OF
CONVECTION FROM EASTERN WA TO NORTHWEST WY. THIS WILL BE MAIN CONCERN
THIS EVENING ACROSS FORECAST AREA. UPPER LOW ACROSS NORTHERN CALIF
HAS SHORTWAVE UNDERCUTTING INTO WESTERN NV. THIS IS SPARKING STRONG
CELLS INTO SOUTHEAST ORE...MODELS TEND TO BRING THIS PRECIP ACROSS
CWA LATE TONIGHT INTO EARLY FRIDAY SO WILL LEAVE THUNDERSTORM THREAT
OVERNIGHT. NGM FORECAST -6 LIFTED INDEX AT 6 AM FRIDAY AS SYSTEM
MOVES INTO WESTERN MT. TROUGH MOVES OVER WESTERN MT FRIDAY FOR DAY OF
SCATTERED SHOWERS AND T-STORMS...THEN LINGERS INTO EARLY SATURDAY.
OUTSIDE CHANCE OF TROPICAL MOISTURE INJECTING TROUGH FRIDAY...WHEN
MODELS HAVE HIGHER QPF AMOUNTS. MOS TEMPS ONLY IN UPPER 70S FOR HIGHS
MANY LOCATIONS ON SATURDAY...NOT BAD FOR AUGUST 1ST. SLOW MOVING
CONVECTION STILL A THREAT FOR FLASH FLOODING IN IDAHO BUT BELIEVE
MAIN PRECIP COMING FRIDAY FROM ACTIVE TROUGH. LOWERING TEMPS AND
RAISING POPS.   BOLDT

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

LIB .. 060/085 059/082 ... 285542
FCA TB 056/081 055/078 053 285553
POL .. 059/082 057/080 ... 285553
MSO TB 059/082 057/080 054 285553
HMM .. 060@/084 058/082 ... 285553
BTM .. 055/080 053/078 ... 286553
S80 .. 061/085 056/084 ... 285532
P69 .. 062/089 060/088 ... 285532
SMN .. 055/088 053/087 ... 285431

Nearby

Severe Thunderstorm Warnings in Idaho, 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.