Alert archive / Montana / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 41, NWS Great Falls, MT

July 4, 1998Cascade County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jul 4, 1998, 5:25 PM MDT for Cascade County, Montana. It was in force for 60 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 4, 1998, 5:25 PM MDT (23:25 UTC)
Expired
Jul 4, 1998, 6:25 PM MDT
In force
60 min
Issued by
NWS Great Falls, MT
Area
Whole counties

County Cascade County, MT

The radar

The Great Falls radar (KTFX), 17 km from the middle of the area, began a volume at 23:25 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 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 12:00Z, 11.4 hours before the alert went out and 59 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 1998-07-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 149 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 1998-07-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -1 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
149 J/kg
Mixed-layer CIN
-293 J/kg
Mixed-layer LCL
1077 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
35 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

686 
WUUS1 KGTF 042327 RRA
SVRGTF
MTC013-050025-

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


THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CASCADE COUNTY IN CENTRAL MONTANA

* UNTIL 625 PM MDT

* AT 522 PM MDT... DOPPLER RADAR AT GREAT FALLS INDICATED A SEVERE
  THUNDERSTORM 30 MILES SOUTHWEST OF GREAT FALLS OR 12 MILES WEST
  OF CASCADE MOVING NORTHEAST AT 30 MPH.

* SOME LOCATIONS IN OR NEAR THE PATH OF THIS STORM ARE...CASCADE...
  ULM...GREAT FALLS.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 3, 6:18 PM MDTSevere Thunderstorm WarningTFXPondera32 min
Jul 3, 6:33 PM MDTSevere Thunderstorm WarningTFXLewis and Clark32 min
Jul 3, 6:56 PM MDTSevere Thunderstorm WarningTFXJefferson34 min
Jul 3, 7:10 PM MDTSevere Thunderstorm WarningTFXGlacier35 min
Jul 3, 7:22 PM MDTSevere Thunderstorm WarningTFXCascade, Lewis and Clark43 min
Jul 3, 7:48 PM MDTSevere Thunderstorm WarningTFXCascade47 min
Jul 3, 7:57 PM MDTSevere Thunderstorm WarningTFXChouteau, Teton48 min
Jul 3, 8:01 PM MDTSevere Thunderstorm WarningTFXLewis and Clark59 min
Jul 3, 8:06 PM MDTSevere Thunderstorm WarningTFXMeagher29 min
Jul 3, 8:09 PM MDTSevere Thunderstorm WarningTFXFergus, Judith Basin61 min
Jul 3, 8:16 PM MDTSevere Thunderstorm WarningTFXLiberty, Pondera, Toole64 min
Jul 3, 8:17 PM MDTTornado WarningTFXCascade, Chouteau18 min
Jul 3, 8:36 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau, Teton49 min
Jul 3, 8:36 PM MDTSevere Thunderstorm WarningTFXLiberty, Pondera, Toole49 min
Jul 3, 8:39 PM MDTSevere Thunderstorm WarningTFXFergus, Judith Basin, Meagher51 min
Jul 3, 8:59 PM MDTTornado WarningTFXCascade, Meagher21 min
Jul 3, 9:00 PM MDTFlash Flood WarningTFXChouteau, Fergus, Judith Basin3 hr
Jul 3, 9:06 PM MDTSevere Thunderstorm WarningTFXBroadwater, Jefferson49 min
Jul 3, 9:26 PM MDTSevere Thunderstorm WarningTFXChouteau, Fergus, Hill, Judith Basin, Liberty49 min
Jul 3, 9:30 PM MDTSevere Thunderstorm WarningTFXBroadwater, Meagher50 min
Jul 3, 10:07 PM MDTSevere Thunderstorm WarningTFXChouteau, Fergus, Judith Basin58 min
Jul 3, 10:07 PM MDTSevere Thunderstorm WarningTFXBlaine, Hill58 min
Jul 3, 10:40 PM MDTSevere Thunderstorm WarningTFXMeagher50 min
Jul 3, 11:10 PM MDTSevere Thunderstorm WarningTFXJudith Basin60 min
Jul 4, 12:15 AM MDTSevere Thunderstorm WarningTFXJudith Basin45 min
Jul 4, 2:42 PM MDTSevere Thunderstorm WarningTFXJudith Basin63 min
Jul 4, 4:04 PM MDTSevere Thunderstorm WarningTFXGallatin, Madison61 min
Jul 4, 4:27 PM MDTSevere Thunderstorm WarningTFXFergus63 min
Jul 4, 4:47 PM MDTSevere Thunderstorm WarningTFXGallatin48 min
Jul 4, 5:29 PM MDTSevere Thunderstorm WarningTFXFergus51 min
Jul 4, 5:47 PM MDTSevere Thunderstorm WarningTFXMeagher63 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; radar from the NEXRAD Level II archive.