Alert archive / Montana / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 64, NWS Great Falls, MT

July 10, 1998Pondera County, Teton County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jul 10, 1998, 4:54 PM MDT for Pondera County, Teton County, Montana. It was in force for 61 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 10, 1998, 4:54 PM MDT (22:54 UTC)
Expired
Jul 10, 1998, 5:55 PM MDT
In force
61 min
Issued by
NWS Great Falls, MT
Area
Whole counties

Counties Pondera County, MT, Teton County, MT

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 10.9 hours before the alert went out and 138 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 1998-07-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 147 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 1998-07-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 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
147 J/kg
Mixed-layer CIN
-223 J/kg
Mixed-layer LCL
2441 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
22 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.

364 
WUUS1 KGTF 102255 RRA
SVRGTF
MTC073-099-102355-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
454 PM MDT FRI JUL 10 1998


THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL PONDERA COUNTY IN NORTHWESTERN MONTANA
  NORTHERN TETON COUNTY IN NORTHWESTERN MONTANA

* UNTIL 555 PM MDT

* AT 454 PM MDT... DOPPLER RADAR AT GREAT FALLS INDICATED A SEVERE
  THUNDERSTORM IN WESTERN TETON COUNTY MOVING NORTHEAST AT 20 MPH.

* THE SEVERE THUNDERSTORMS WILL BE NEAR DUPUYER BY 515 PM MDT.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 10, 5:19 PM MDTSevere Thunderstorm WarningTFXChouteau61 min
Jul 10, 5:44 PM MDTSevere Thunderstorm WarningTFXCascade31 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; the sounding from the Mesonet's radiosonde archive.