Alert archive / Montana / Severe Thunderstorm Warnings in 1989

Severe Thunderstorm Warning 2, NWS Missoula, MT

May 10, 1989Jefferson County, Silver Bow County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at May 10, 1989, 12:03 PM MDT for Jefferson County, Silver Bow County, Montana. It was in force for 57 min.

The area

The counties it named.

The facts

Issued
May 10, 1989, 12:03 PM MDT (18:03 UTC)
Expired
May 10, 1989, 1:00 PM MDT
In force
57 min
Issued by
NWS Missoula, MT
Area
Whole counties

Counties Jefferson County, MT, Silver Bow 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

Great Falls, MT (KGTF), launched 12:00Z, 6.1 hours before the alert went out and 181 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 1989-05-10Temperature 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 1989-05-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 95 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1682 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
95 m²/s²
0-3 km storm-relative helicity
92 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 KHLN 101804
SVRHLN
MTC043-093-101900-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HELENA MT
1203 PM MDT WED MAY 10 1989
 
THE NATIONAL WEATHER SERVICE IN HELENA MT     HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  100 PM MDT
FOR PEOPLE IN THE FOLLOWING COUNTIES...
 
IN SOUTHWEST MONTANA
          ...SOUTHERN HALF JEFFERSON...NORTHERN HALF SILVER BOW
 
AT 1130AM MDT RADAR IN MISSOULA INDICATED RAPIDLY DEVELOPING
THUNDERSTORMS IN THE VICINITY OF BUTTE. AT 1145AM MDT BUTTE FLIGHT
SERVICE STATION REPORTED WIND GUSTS TO 75 MPH WITH HAIL. THESE STORMS
ARE MOVING TO THE NORTHEAST AT 40 TO 45 MPH. PERSONS IN THE NORTHERN
HALF OF SILVER BOW AND THE SOUTHERN HALF OF JEFFERSON COUNTIES SHOULD
BE ON THE ALERT FOR THESE STORMS FOR THE NEXT HOUR.
 
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

The office that day

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

IssuedProductOfficeCountiesLasted
May 9, 11:59 PM MDTSevere Thunderstorm WarningMSOMissoula, Ravalli61 min
May 10, 12:49 PM MDTSevere Thunderstorm WarningMSOJefferson, Lewis and Clark116 min
May 10, 2:26 PM MDTSevere Thunderstorm WarningMSOMissoula64 min

Nearby

Severe Thunderstorm Warnings in Montana, 1989Every severe thunderstorm warning in 1989

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.