Alert archive / Montana / Tornado Warnings in 1990

Tornado Warning 3, NWS Great Falls, MT

July 5, 1990Cascade County, Montana

NWS Great Falls, MT issued this tornado warning at Jul 5, 1990, 9:23 PM MDT for Cascade County, Montana. It was in force for 52 min.

The area

The counties it named.

The facts

Issued
Jul 5, 1990, 9:23 PM MDT (03:23 UTC)
Expired
Jul 5, 1990, 10:15 PM MDT
In force
52 min
Issued by
NWS Great Falls, MT
Area
Whole counties

County Cascade County, MT

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Glasgow Intl Airport, MT (KGGW), launched 00:00Z, 3.4 hours before the alert went out and 369 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, Glasgow Intl Airport, MT at 00:00Z on 1990-07-06Temperature 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, Glasgow Intl Airport, MT at 00:00Z on 1990-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -19 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
2700 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
-19 m²/s²
0-3 km storm-relative helicity
226 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 060324
TORGTF
MTC013-060415-
 
BULLETIN - EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
923 PM MDT THU JUL 5 1990
 
THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A
TORNADO WARNING EFFECTIVE UNTIL 1015 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATION......
 
IN NORTH CENTRAL MONTANA
 
   ...EXTREME NORTHERN CASCADE COUNTY AND SOUTHERN CHOTEAU COUNTY
 
AT 915PM MDT A POSSIBLE TORNADO WAS SIGHTED NORTH OF MALMSTROM AFB.
THIS STORM WAS MOVING NORTHEAST AND WILL MOVE INTO SOUTHWEST CHOTEAU
COUNTY DURING THE NEXT HOUR.
 
THIS STORM IS NORTH OF THE CITY OF GREAT FALLS AND MOVING AWAY TO THE
NORTHEAST.
 
 
 
IF YOU LIVE IN A HOME OR APARTMENT...SEEK SHELTER IN THE
bINNERMOST PORTION OF THE BUILDING ON THE LOWEST FLOOR.  GET TO
A BASEMENT IF ONE IS AVAILABLE.  AVOID WINDOWS AND PROTECT YOUR
BODY FROM FLYING DEBRIS WITH CUSHIONS...BLANKETS...OR PILLOWS.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 5, 8:39 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau66 min
Jul 5, 9:54 PM MDTSevere Thunderstorm WarningTFXBlaine, Hill66 min
Jul 5, 10:19 PM MDTSevere Thunderstorm WarningTFXChouteau56 min
Jul 5, 10:56 PM MDTSevere Thunderstorm WarningTFXBlaine, Hill64 min
Jul 6, 12:02 AM MDTSevere Thunderstorm WarningTFXBlaine58 min
Jul 6, 12:52 AM MDTSevere Thunderstorm WarningTFXBlaine68 min

Nearby

Tornado Warnings in Montana, 1990Every tornado warning in 1990Tornadoes in 1990

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.