Alert archive / Montana / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 93, NWS Great Falls, MT

August 1, 2000Fergus County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Aug 1, 2000, 3:34 PM MDT for Fergus County, Montana. It was in force for 41 min. 3 reports 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
Aug 1, 2000, 3:34 PM MDT (21:34 UTC)
Expired
Aug 1, 2000, 4:15 PM MDT
In force
41 min
Issued by
NWS Great Falls, MT
Area
Whole counties

County Fergus County, MT

What was reported inside it

TimeReportWhereRemark
Aug 1, 3:40 PM MDTThunderstorm Wind 52 EMoore, MTBlew down several cottonwood trees.
Aug 1, 3:40 PM MDTHail 0.75Garneill, MT
Aug 1, 4:15 PM MDTHail 0.88Grassrange, 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.

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 9.6 hours before the alert went out and 106 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 2000-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 38 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 2000-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -12 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
38 J/kg
Mixed-layer CIN
-278 J/kg
Mixed-layer LCL
2886 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
-12 m²/s²
0-3 km storm-relative helicity
45 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 
WUUS55 KTFX 012134
SVRGTF
MTC027-012215-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
334 PM MDT TUE AUG 1 2000

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL FERGUS COUNTY IN CENTRAL MONTANA

* UNTIL 415 PM MDT

* AT 322 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER EXTREME SOUTHWESTERN FERGUS COUNTY...OR   
ABOUT 10 MILES EAST OF GARNEIL...MOVING EAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL REMAIN OVER...
THE SNOWY MOUNTAINS THROUGH 415 PM.

HAIL TO ONE INCH IN DIAMETER AND WIND GUSTS TO 60 MPH ARE POSSIBLE 
WITH THIS STORM.

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 4689 10973 4677 10972 4677 10916 4694 10920

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 Aug 1, 3:00 PM MDT, 34 minutes earlier.

Area forecast discussion, Aug 1, 3:00 PM MDT, 34 minutes before
SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
300 PM MDT TUE AUG 1 2000

UPPER LOW MOVING EWD ACROSS WRN ALBERTA...WITH UPPER HIGH STATIONARY
OVER THE GREAT BASIN. WEAK UPPER LEVEL RIDGE OVER MONTANA. SURFACE FRONT
MOVING SLOWLY EWD ACROSS CWA.  WATER VAPOR IMAGERY SHOWS SHORT WAVE
MOVING EWD INTO SWRN MT...ETA MODEL HANDLING THIS FEATURE QUITE WELL.
THIS FEATURE ALONG WITH DECREASING STABILITY THIS AFTERNOON AND EVENING
WILL FIRE SOME THUNDERSTORMS OVER SWRN ZONES...WITH MOVE ACTIVITY
EXPECTED IN EASTERN CWA IN VICINITY OF SFC FRONT. ACTIVITY WILL DIE OFF
FROM WEST TO EAST AFTER SUNSET.

AIRMASS BECOMES INCREASINGLY STABLE AND DRIER TONIGHT...LASTING THROUGH
THURSDAY...AS FLAT UPPER RIDGE BUILDS OVER AREA. AFTER TEMPERATURES COOL
A BIT INTO WED...THICKNESSES INCREASE ONCE AGAIN FOR WARMING
TEMPERATURES ON THUR. THERE REMAINS THE THREAT OF ISOLD AFTN/EVE TSTMS
OVER MOUNTAINS WED-THUR. JOHNSON

EXTENDED DISCUSSION...
BOTH MRF AND ECMWF MODELS HAS H5 RIDGE OVER AREA WITH A DEVELOPING TROF
OVR THE PAC NW. MRF HAS PAC NW TROF MORE PROGRESSIVE BY SUNDAY...WHILE
ECMWF HAS RIDGE OVR ERN MT. CONTINUED WARM AND MAINLY DRY WEATHER
THROUGH SATURDAY...WITH A CHANCE OF THUNDERSTORMS SUNDAY.

CCF NUMBERS
GTF UU 054/091 053/093 057 121000
CTB UU 050/086 049/088 053 120001
HLN BB 055/092 053/094 056 122211
BZN BB 052/092 050/093 052 122211
WEY BB 042/084 040/086 043 123211
DLN BB 051/088 048/089 050 122211
HVR UU 056/092 053/093 056 123300
LWT BU 053/087 051/089 054 123300

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 4:10 PM MDTSevere Thunderstorm WarningTFXFergus50 min

Nearby

Severe Thunderstorm Warnings in Montana, 2000Every 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.