Alert archive / Montana / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 95, NWS Great Falls, MT

August 12, 2003Chouteau County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Aug 12, 2003, 8:02 PM MDT for Chouteau County, Montana. It was in force for 43 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 12, 2003, 8:02 PM MDT (02:02 UTC)
Expired
Aug 12, 2003, 8:45 PM MDT
In force
43 min
Issued by
NWS Great Falls, MT
Area
Counties, with a storm outline in the text

County Chouteau County, MT

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 2.0 hours before the alert went out and 70 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 00:00Z on 2003-08-13Temperature 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 00:00Z on 2003-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 67 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
3243 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
67 m²/s²
0-3 km storm-relative helicity
248 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS55 KTFX 130202
SVRTFX
MTC015-130245-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
802 PM MDT TUE AUG 12 2003

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

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

* UNTIL 845 PM MDT

* AT 758 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 12 MILES SOUTH OF THE KNEES...OR ABOUT 25 MILES
  NORTH OF GREAT FALLS...MOVING EAST AT 45 MPH.

* THE SEVERE THUNDERSTORM WILL MOVE OVER...
RURAL CENTRAL CHOUTEAU COUNTY THROUGH 845 PM MDT

IF SEVERE WEATHER APPROACHES YOUR AREA...GO INSIDE A STURDY SHELTER
AWAY FROM CREEK BEDS AND OTHER FLOOD-PRONE AREAS. REMEMBER...A SEVERE
THUNDERSTORM CAN PRODUCE LARGE DAMAGING HAIL...DAMAGING WINDS IN
EXCESS OF 55 MPH...DEADLY LIGHTNING...AND VERY HEAVY RAIN.

REPORT SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE FORECAST 
OFFICE IN GREAT FALLS 1-800-932-6694.

LAT...LON 4791 11140 4777 11123 4800 11069 4811 11094
          4810 11133

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 12, 2:40 PM MDT, 5 hours 22 minutes earlier.

Area forecast discussion, Aug 12, 2:40 PM MDT, 5 hours 22 minutes before
SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST
NATIONAL WEATHER SERVICE GREAT FALLS MT
240 PM MDT TUE AUG 12 2003

.DISCUSSION...

SW FLOW ALOFT BRINGING ABUNDANT UPPER LEVEL MOISTURE ACROSS THE AREA
THIS EVENING ALONG WITH SHORT WAVE AND ASSOCIATED VORTICITY CENTER
THAT MAY DEVELOP THUNDERTORMS TONIGHT. INHIBITING FACTOR ACROSS
WESTERN CWA IS CLOUDS AND CURRENT TEMPERATURES IN THE 80S ACROSS
MUCH OF CENTRAL MONTANA. TEMPERATURES NEAR 100 EAST WILL ENHANCE
THUNDERSTORMS ACTIVITY THIS EVENING. LITTLE CHANGE IN PATTERN WED...
WITH DECREASING CHANCE OF RAIN AS RIDGE STARTS TO BUILD OVER AREA.
HIGH PRESSURE CONTINUES TO BUILD OVER REGION THURSDAY AND FRIDAY
BRINGING NEAR RECORD HIGH TEMPERATURES TO THE AREA AND ONLY SLIGHT
CHANCE OF MAINLY AFTERNOON THUNDERSTORMS. STRONGER WINDS FRIDAY
AFTERNOON...20 MPH OR MORE ALONG ROCKY MOUNTAIN FRONT...WILL
COMBINE WITH HIGH TEMPERATURES AND LOW HUMIDITIES TO CREATE
PARTICULARLY DANGEROUS FIRE CONDITIONS.

FRIDAY NIGHT THROUGH SATURDAY...GFS RUN SHOWS A WAVE MOVING OVER THE
TOP OF THE RIDGE FRIDAY EVENING. THE RESPONSE TO THIS WAVE WILL BE
FOR A SURFACE LOW TO FORM OVER CENTRAL AND EASTERN MONTANA/SOUTHERN
SASKATCHEWAN WHICH WILL CREATE DOWNSLOPE WINDS.  WILL TEMPER THESE
WIND SPEEDS FOR NOW HOPING FOR SOME CONSISTENCY IN THE MODEL RUNS.
HOWEVER...IT COULD BE A BIT WINDY FRIDAY NIGHT AND SATURDAY.
CONSEQUENTLY...NO RAIN FOR OUR AREA FRIDAY NIGHT THROUGH SATURDAY
AND CONTINUED HOT.
DITTMANN

.SUNDAY THROUGH TUESDAY...UPPER LEVEL RIDGE REBUILDS RAPIDLY BY
SUNDAY. THE MODELS KEPT DELAYING THE COOLER WEATHER BY A DAY OVER
THE LAST 3 DAYS. THUS WILL GO WITH A RIDGE OVER THE AREA FOR
CONTINUED HOT AND DRY WEATHER THROUGH TUESDAY. WILLIAMSON DC

.CCF NUMBERS
GTF BB 057/096 059/100 061 01322
    BBUUU 097/061 092/061 092/058 091/058 092 21-00000000
CTB BB 051/092 054/094 060 01222
    BBUUU 093/057 089/057 083/055 088/055 089 22100000000
HLN BB 058/096 060/099 059 01321
    BBUUU 099/060 094/060 091/060 093/060 092 11-00000000
BZN BB 054/099 053/100 057 01321
    BBUUU 096/059 093/059 091/055 092/055 091 11000000000
WEY BB 048/091 049/093 055 01321
    UUUUU 089/050 089/051 086/044 088/044 086 11011000000
DLN BB 054/097 057/099 057 01321
    BUUUU 095/056 093/056 093/050 092/050 093 111--000000
HVR BB 060/100 062/102 062 01322
    BBUUU 100/060 095/060 094/063 094/063 095 21100000000
LWT BB 058/098 060/100 062 01322
    BBUUU 098/060 093/060 091/060 092/060 089 21-00000000

.TFX...RED FLAG WARNING TODAY THROUGH TONIGHT FOR FIRE ZONES 112...
113...114...115...116...117 AND 118.
Hazardous weather outlook, Aug 12, 3:15 PM MDT, 4 hours 47 minutes before
MTZ008>015-044>055-131210-
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREAT FALLS MT
315 PM MDT TUE AUG 12 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND SOUTHWEST MONTANA

.DAY ONE...TODAY

A RED FLAG WARNING CONTINUES THROUGH THIS EVENING FOR ALL OF NORTH
CENTRAL AND SOUTHWEST MONTANA FOR LOW RELATIVE HUMIDITIES...HIGH
FIRE DANGERS AND GUSTY WINDS ASSOCIATED WITH A MIX OF WET AND DRY
THUNDERSTORMS. PLEASE REFER TO GTFRFWTFX AND GTFRFWMSO FOR MORE
INFORMATION.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

INCREASING TEMPERATURES AND LOW RELATIVE HUMIDITIES WILL CONTRIBUTE
TO VERY HIGH FIRE DANGERS THROUGH AT LEAST FRIDAY. THERE IS ALSO A
SLIGHT CHANCE OF THUNDERSTORMS EACH DAY. THEREFORE RED FLAG
CONDITIONS WILL BE POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 8:47 PM MDTSevere Thunderstorm WarningTFXChouteau, Hill58 min
Aug 12, 9:03 PM MDTSevere Thunderstorm WarningTFXTeton42 min

Nearby

Severe Thunderstorm Warnings in Montana, 2003Every severe thunderstorm warning in 2003

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.