Alert archive / Montana / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 49, NWS Great Falls, MT

July 5, 1998Teton County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jul 5, 1998, 3:45 PM MDT for Teton County, Montana. It was in force for 60 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
Jul 5, 1998, 3:45 PM MDT (21:45 UTC)
Expired
Jul 5, 1998, 4:45 PM MDT
In force
60 min
Issued by
NWS Great Falls, MT
Area
Whole counties

County Teton County, MT

The radar

The Great Falls radar (KTFX), 77 km from the middle of the area, began a volume at 21:48 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

TimeReportWhereRemark
Jul 5, 4:37 PM MDTHail 1.75Fairfield, 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, 9.8 hours before the alert went out and 130 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 1998-07-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 1998-07-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1987 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
35 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 KGTF 052145 RRA
SVRGTF
MTC099-052245-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
345 PM MDT SUN JUL 5 1998


THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN AND CENTRAL TETON COUNTY IN NORTHWESTERN MONTANA

* UNTIL 445 PM MDT

* AT 345 PM MDT... DOPPLER RADAR AT GREAT FALLS INDICATED A SEVERE
  THUNDERSTORM 13 MILES SOUTHWEST OF CHOTEAU MOVING NORTHEAST AT 15
  MPH.

* SOME LOCATIONS IN OR NEAR THE PATH OF THIS STORM ARE...   CHOTEAU
  AND   FAIRFIELD.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 4, 6:00 PM MDTSevere Thunderstorm WarningTFXToole65 min
Jul 4, 6:05 PM MDTSevere Thunderstorm WarningTFXPondera, Teton65 min
Jul 4, 7:05 PM MDTSevere Thunderstorm WarningTFXChouteau, Pondera60 min
Jul 4, 7:12 PM MDTSevere Thunderstorm WarningTFXToole58 min
Jul 4, 9:31 PM MDTSevere Thunderstorm WarningTFXGlacier, Toole64 min
Jul 5, 4:15 PM MDTSevere Thunderstorm WarningTFXToole45 min
Jul 5, 4:50 PM MDTSevere Thunderstorm WarningTFXTeton60 min
Jul 5, 5:00 PM MDTSevere Thunderstorm WarningTFXLiberty, Toole65 min
Jul 5, 5:37 PM MDTSevere Thunderstorm WarningTFXChouteau63 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.