Alert archive / Montana / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 115, NWS Great Falls, MT

September 5, 2000Chouteau County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Sep 5, 2000, 5:35 PM MDT for Chouteau County, Montana. It was in force for 40 min. 4 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
Sep 5, 2000, 5:35 PM MDT (23:35 UTC)
Expired
Sep 5, 2000, 6:15 PM MDT
In force
40 min
Issued by
NWS Great Falls, MT
Area
Whole counties

County Chouteau County, MT

The radar

The Great Falls radar (KTFX), 85 km from the middle of the area, began a volume at 23:37 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.

What was reported inside it

TimeReportWhereRemark
Sep 5, 5:45 PM MDTHail 1.75Highwood, MT
Sep 5, 5:45 PM MDTHail 1.25Shonkin, MT
Sep 5, 6:00 PM MDTHail 1Geraldine, MT
Sep 5, 6:22 PM MDTHail 1Geraldine, 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

Spokane, WA (KOTX), launched 12:00Z, 11.6 hours before the alert went out and 446 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, Spokane, WA at 12:00Z on 2000-09-05Temperature 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, Spokane, WA at 12:00Z on 2000-09-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 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
1123 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
-8 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 052340
SVRGTF
MTC015-060015-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING...CORRECTED FOR TYPO
NATIONAL WEATHER SERVICE GREAT FALLS MT
535 PM MDT TUE SEP 5 2000

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN CHOUTEAU COUNTY IN NORTH CENTRAL MONTANA

* UNTIL 615 PM MDT

* AT 534 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM NEAR HIGHWOOD OR 7 MILES NORTHEAST OF BELT...
MOVING NORTHEAST AT 45 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  GERALDINE AT 600 PM MDT

HAIL UP TO ONE INCH IN DIAMETER HAS BEEN REPORTED WITH THIS
STORM. IF YOU ARE IN THE PATH OF THE STORM...PUT YOUR CAR IN A
GARAGE AND MOVE TO A SUBSTANTIAL SHELTER.

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 4755 11079 4744 11069 4749 11012 4768 10990
          4786 11022

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 Sep 5, 3:00 PM MDT, 2 hours 35 minutes earlier.

Area forecast discussion, Sep 5, 3:00 PM MDT, 2 hours 35 minutes before
SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
300 PM MDT TUE SEP 5 2000

SLOW BUT STEADY MOVEMENT OF TROF TOWARDS THE EAST. A SECOND TROF OVER
BRITISH COLUMBIA MOVES ACROSS THE HI LINE AND JOINS WITH NORTHERN BRANCH
OF TROF...LEAVING THE SOUTHERN END OF THE TROF BEHIND. TROF SHOULD BE
ACROSS THE ROCKIES IN THE NORTH BY 12Z WEDNESDAY...OVER EXTREME ERN MT
BY EVENING.  MID-HI LVL CLOUD COVER ASSOCIATED WITH THE AXIS...AND QUITE
A BIT OF LOW LVL MOISTURE ACROSS THE STATE CAUSING SOME LOWER LEVEL
CLOUDS. SEVERAL WEAK VORT LOBES MOVING THRU SWLY FLOW AHEAD OF
TROF...HOWEVER MOSTLY SHEAR VORT AND VERY LITTLE VERTICAL VELOCITY IS
CREATED. SO COMBINATION OF MOISTURE AND INSTABILITY AGAIN APPEARS TO BE
SOURCE OF ACTION...AND NOTICED THAT BUTTE IS REPORTING TCU ALL QUADS.
ONE ITEM OF CONCERN IS WHETHER THE SHORT WAVE IN BRITISH COLUMBIA WILL
CONTINUE TO MOVE QUICKLY TO THE EAST OR GET CAUGHT UP WITH THE SLOWER
MOVING TROF OVER THE ROCKIES. AT THE MOMENT ONLY LOOKING AT A PERIOD OF
ENHANCED DYNAMICS ALONG THE NORTHERN ZONES. ALSO...A SECONDARY COLD
FRONT IS ASSOCIATED WITH THE FASTER MOVING SHORT WAVE. THIS MAY DRIFT
FURTHER SOUTH THAN THE CURRENT PROGS DEPICT...ALTHO THE LATEST MESO DOES
BRING THE 552 THICKNESS SOUTH OF THE CANADIAN BORDER. RIDGING OVER THE
PAC NW BY WEDNESDAY AFTN...AND EXCEPT FOR SOME AREAS IN THE SOUTH WILL
BE IN A DRIER AND COOLER AIRMASS.  WIND NEEDS TO BE MENTIONED AS THE
TROF MOVES EAST AND WINDS GO WESTERLY...NOT ANYTHING OUT OF THE ORDINARY
THOUGH. ZELZER

EXTENDED DISCUSSION...IT SEEMS LIKE EVERY VERSION OF THE MRF HAS A
DIFFERENT SHORT WAVE PATTERN...ALTHOUGH THE LONG WAVE FEATURES ARE
FAIRLY CONSISTENT. THE MAIN MESSAGE ON THE PROGS IS THAT THE WESTERLIES
WILL BE BREAKING INTO MONTANA DURING THE 3 TO 5 DAY PERIOD. SHORT WAVE
DETAILS BETWEEN MRF...72HOUR AVN...72HOUR UKMET AND ECMWF ARE ALL
DIFFERENT. ALL BUT THE MRF HINT AT MORE DIGGING OF MAIN LONG WAVE
TROUGH...ESPECIALLY ECMWF. WILL FORECAST MOSTLY DRY AND WINDY WITH
SHOWERS IN THE NORTHERN MOUNTAINS IN THE 3 TO 5 DAY FORECAST. OARD

CCF NUMBERS
GTF EB 050/070 045/076 048 133111
CTB BB 0i49/065 045/072 044 132111
HLN EB 050/070 045/076 042 134111
BZN EB 040/075 036/077 038 134111
WEY EB 032/066 028/068 030 134111
DLN EB 038/072 036/074 038 134111
HVR EB 050/070 046/076 046 133111
LWT EB 050/065 044/070 044 133111

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 4, 10:49 PM MDTSevere Thunderstorm WarningTFXChouteau26 min
Sep 4, 11:14 PM MDTSevere Thunderstorm WarningTFXChouteau31 min
Sep 4, 11:44 PM MDTSevere Thunderstorm WarningTFXBlaine, Chouteau46 min
Sep 5, 12:12 AM MDTSevere Thunderstorm WarningTFXCascade33 min
Sep 5, 3:52 PM MDTSevere Thunderstorm WarningTFXCascade, Lewis and Clark38 min
Sep 5, 3:55 PM MDTSevere Thunderstorm WarningTFXChouteau50 min
Sep 5, 4:12 PM MDTSevere Thunderstorm WarningTFXCascade48 min
Sep 5, 4:58 PM MDTSevere Thunderstorm WarningTFXCascade47 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; radar from the NEXRAD Level II archive.