Alert archive / Montana / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 2, NWS Missoula, MT

July 2, 1990Broadwater County, Lewis and Clark County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Jul 2, 1990, 3:49 PM MDT for Broadwater County, Lewis and Clark County, Montana. It was in force for 56 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 2, 1990, 3:49 PM MDT (21:49 UTC)
Expired
Jul 2, 1990, 4:45 PM MDT
In force
56 min
Issued by
NWS Missoula, MT
Area
Whole counties

Counties Broadwater County, MT, Lewis and Clark County, MT

The radar

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

What was reported inside it

TimeReportWhereRemark
Jul 2, 4:00 PM MDTThunderstorm Wind 0Lewis And Clark, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Great Falls, MT (KGTF), launched 12:00Z, 9.8 hours before the alert went out and 97 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 1990-07-02Temperature 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 1990-07-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 24 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2690 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
24 m²/s²
0-3 km storm-relative helicity
72 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 022149
SVRHLN
MTC007-049-022245-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HELENA MT
349 PM MDT MON JUL 2 1990
 
THE NATIONAL WEATHER SERVICE IN HELENA HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  445 PM MDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTHWEST MONTANA
 
   ...BROADWATER COUNTY...EASTERN LEWIS AND CLARK COUNTY
 
A SEVERE THUNDERSTORM PASSED OVER HELENA AT 345 PM THIS MONDAY
AFTERNOON. IT PRODUCED WINDS GUSTING TO 65 MPH AND 1/2 INCH HAIL. THIS
STORM IS ONCE OF SEVERAL THAT ARE MOVING TO THE EAST. PERSONS IN THE
PATH OF THESE STORMS SHOULD TAKE SHELTER.
 
THIS IS A DANGEROUS STORM.  IF YOU ARE IN ITS PATH YOU SHOrULD
PREPARE FOR DAMAGING WIND IN EXCESS OF 55 MPH...LARGE HAIL...AND
DEADLY LIGHTNING.  PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT STAY AWAY FROM WINDOWS.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 2, 4:01 PM MDTSevere Thunderstorm WarningMSOMeagher59 min
Jul 2, 4:39 PM MDTSevere Thunderstorm WarningMSOBroadwater, Lewis and Clark, Meagher66 min

Nearby

Severe Thunderstorm Warnings in Montana, 1990Every severe thunderstorm warning 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.