Alert archive / Montana / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 18, NWS Great Falls, MT

June 22, 2000Beaverhead County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jun 22, 2000, 1:09 PM MDT for Beaverhead County, Montana. It was in force for 36 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Jun 22, 2000, 1:09 PM MDT (19:09 UTC)
Expired: Jun 22, 2000, 1:45 PM MDT
In force: 36 min
Issued by: NWS Great Falls, MT
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Beaverhead County, MT

The radar

The Missoula radar (KMSX), 166 km from the middle of the area, began a volume at 19:01 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 nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 7.2 hours before the alert went out and 277 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1365 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: -61 m²/s²
0-3 km storm-relative helicity: 156 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.

578 
WUUS55 KTFX 221909
SVRGTF
MTC001-221945-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
109 PM MDT THU JUN 22 2000

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL BEAVERHEAD COUNTY IN SOUTHWEST MONTANA

* UNTIL 145 PM MDT

* AT 106 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 22 MILES SOUTHWEST OF WISE RIVER...OR ABOUT 32
  MILES SOUTHWEST OF ANACONDA...MOVING EAST AT 35 MPH.

* THE SEVERE THUNDERSTORM WILL BE OVER...
RURAL NORTHERN BEAVERHEAD COUNTY AT 120 PM MDT

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A STRONG
BUILDING. DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...AND DEADLY
LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS. STAY INSIDE AWAY
FROM WINDOWS UNTIL THE STORM HAS PASSED.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN GREAT FALLS.

LAT...LON 4574 11344 4556 11346 4553 11273 4567 11276
          4580 11293

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Great Falls, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 22, 9:30 AM MDT, 3 hours 39 minutes earlier.

Area forecast discussion, Jun 22, 9:30 AM MDT, 3 hours 39 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
930 AM MDT THU JUN 22 2000

...UPDATE PLANNED BY 1000 AM...
NESDIS GOES SOUNDINGS INDICATED MOST OF MONTANA EAST OF DIVIDE IS
UNSTABLE. RADAR SHOWS SCATTERED RAINSHOWERS OVER PARTS OF NORTHERN ZONES
AS WELL AS SOUTH CENTRAL ZONES...ALONG WITH A FEW THUNDERSTORMS. THESE
APPEAR TO BE ASSOCIATED WITH A WEAK SHORT WAVE CROSSING THE ROCKIES AND
SHOULD CONTINUE TO MOVE EAST. WESTERLY FLOW ALOFT IS FAIRLY MOIST
HOWEVER WATER VAPOR INDICATES DRY AIR MOVING ACROSS NORTHERN ROCKIES AND
THE AIR MASS WILL BE DRYING FROM THE NORTHWEST...BUT MID LEVELS REMAIN
MOIST. ALOS....INDICES SHOW WIDESPREAD WEAK INSTABLITY AGAIN THIS
AFTERNOON. SW MT UNDER AREA OF DIVERGENCE ALOFT...COMBINED WITH
INSTABILITY AND MOISTURE CONVERGENCE APPEARS SHOULD BE AREA OF HIGHEST
POPS FOR TODAY. ANOTHER SHORT WAVE MOVES ACROSS NORTHERN ZONES AFTER 00Z
AND SHOULD BE ENOUGH TO KICK OFF A FEW THUNDERSTORMS TOWARDS FRIDAY
MORNING.  ZELZER

CCF NUMBERS
GTF BB 078/054 072/045 069 201334
CTB BB 074/050 068/043 066 202335
HLN BE 083/054 076/050 083 202333
BZN BE 082/050 076/044 081 202333
WEY BE 075/035 070/039 075 203334
DLN BE 081/050 076/048 083 202233
HVR BB 081/054 074/049 076 202225
LWT BE 075/050 068/046 068 203245

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 22, 2:02 PM MDT	Severe Thunderstorm Warning	TFX	Madison	28 min
Jun 22, 2:35 PM MDT	Severe Thunderstorm Warning	TFX	Madison	40 min
Jun 22, 2:59 PM MDT	Severe Thunderstorm Warning	TFX	Gallatin	46 min

Nearby

Severe Thunderstorm Warnings in Montana, 2000 Every severe thunderstorm warning in 2000

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.