Alert archive / Montana / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 91, NWS Great Falls, MT
NWS Great Falls, MT issued this severe thunderstorm warning at Aug 23, 1998, 5:08 PM MDT for Chouteau County, Fergus County, Judith Basin County, Montana. It was in force for 62 min. 3 reports 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 23, 1998, 5:08 PM MDT (23:08 UTC)
- Expired
- Aug 23, 1998, 6:10 PM MDT
- In force
- 62 min
- Issued by
- NWS Great Falls, MT
- Area
- Whole counties
Counties Chouteau County, MT, Fergus County, MT, Judith Basin County, MT
The radar
The Great Falls radar (KTFX), 106 km from the middle of the area, began a volume at 23:08 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 23, 5:20 PM MDT | Hail 0.75 | Windham, MT | |
| Aug 23, 5:35 PM MDT | Tornado F0 | Moore, MT | |
| Aug 23, 5:45 PM MDT | Thunderstorm Wind 60 | Hobson, 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, 11.1 hours before the alert went out and 48 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2124 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 20 m²/s²
- 0-3 km storm-relative helicity
- 95 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
074 WUUS1 KGTF 232310 RRA SVRGTF MTC015-027-045-240010- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE GREAT FALLS MT 508 PM MDT SUN AUG 23 1998 THE NATIONAL WEATHER SERVICE HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... SOUTHERN CHOUTEAU COUNTY IN NORTH CENTRAL MONTANA NORTHERN FERGUS COUNTY IN CENTRAL MONTANA NORTHERN JUDITH BASIN COUNTY IN CENTRAL MONTANA * UNTIL 610 PM MDT * DOPPLER RADAR INDICATES SEVERAL RAPIDLY BUILDING THUNDERSTORMS MOVING TOWARDS THE NORTHEAST AT 20 TO 25 MPH. GUSTY WINDS EXCEEDING 60 MPH AND HAIL UP TO 1 INCH IN DIAMETER CAN BE EXPECTED WITH THESE THUNDERSTORMS. TOWNS THAT CAN BE AFFECTED BY THESE THUNDERSTORMS INCLUDE GEYSER...STANFORD...DENTON...AND RAYNESFORD
The office that day
Everything else NWS Great Falls, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 23, 4:17 PM MDT | Severe Thunderstorm Warning | TFX | Cascade | 58 min |
| Aug 23, 5:01 PM MDT | Severe Thunderstorm Warning | TFX | Cascade | 59 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; radar from the NEXRAD Level II archive.