Alert archive / Montana / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 45, NWS Great Falls, MT

July 4, 1998Pondera County, Teton County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jul 4, 1998, 6:05 PM MDT for Pondera County, Teton County, Montana. It was in force for 65 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 4, 1998, 6:05 PM MDT (00:05 UTC)
Expired
Jul 4, 1998, 7:10 PM MDT
In force
65 min
Issued by
NWS Great Falls, MT
Area
Whole counties

Counties Pondera County, MT, Teton County, MT

What was reported inside it

TimeReportWhereRemark
Jul 4, 7:15 PM MDTHail 1.75Brady, 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 4, 2:30 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 0.1 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 00:00Z on 1998-07-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1001 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 00:00Z on 1998-07-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -7 square meters per square second.1939587897Sfc1 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
1001 J/kg
Mixed-layer CIN
-77 J/kg
Mixed-layer LCL
1485 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
59 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

859 
WUUS1 KGTF 050007 RRA
SVRGTF
MTC073-099-050110-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
605 PM MDT SAT JUL 4 1998


THE NATIONAL WEATHER SERVICE HAS ISSUED A

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

* UNTIL 710 PM MDT

* AT 603 PM MDT... DOPPLER RADAR AT GREAT FALLS INDICATED A SEVERE
  THUNDERSTORM 9 MILES SOUTHWEST OF CONRAD OR 8 MILES WEST OF BRADY
  MOVING EAST AT 15 MPH.

* SOME LOCATIONS IN OR NEAR THE PATH OF THIS STORM ARE...
  CONRAD...   BRADY AND   COLLINS AREA.

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, 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, 3:45 PM MDTSevere Thunderstorm WarningTFXTeton60 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.