Alert archive / Montana / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 97, NWS Great Falls, MT

August 12, 2003Teton County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Aug 12, 2003, 9:03 PM MDT for Teton County, Montana. It was in force for 42 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, 9:03 PM MDT (03:03 UTC)
Expired: Aug 12, 2003, 9:45 PM MDT
In force: 42 min
Issued by: NWS Great Falls, MT
Area: Counties, with a storm outline in the text

County Teton 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, 3.1 hours before the alert went out and 96 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: 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 130303
SVRTFX
MTC099-130345-

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

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL TETON COUNTY IN NORTH CENTRAL MONTANA

* UNTIL 945 PM MDT

* AT 858 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 6 MILES NORTHWEST OF POWER...OR ABOUT 19 MILES
  EAST OF CHOTEAU...MOVING NORTH AT 45 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  DUTTON AT 920 PM MDT

* OTHER LOCATIONS IN THE WARNING INCLUDE INTERSTATE 15 BETWEEN POWER 
AND DUTTON.

LARGE HAIL IS LIKELY 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 4795 11203 4765 11177 4772 11144 4796 11144

$$

BRUSDA

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, 8:50 PM MDT, 13 minutes earlier.

Area forecast discussion, Aug 12, 8:50 PM MDT, 13 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST
NATIONAL WEATHER SERVICE GREAT FALLS MT
850 PM MDT TUE AUG 12 2003

.DISCUSSION...

SHORT TERM OUTLOOK...WITH SEVERE WEATHER STARTING UP LATE...WITH
ISSUE AN UPDATE...BUT MAINLY TO REMOVE THUNDERSTORMS OVER SOUTHWEST
AFTER MIDNIGHT. THUNDERSTORMS ARE A RESULT OF A DISTURBANCE IN WEST
CENTRAL MONTANA...SHOULD BE NEAR CANADIAN BORDER NORTH OF HAVRE BY
MIDNIGHT. EXPECT THUNDERSTORM ACTIVITY TO CONTINUE ALONG AND AHEAD
OF THE DISTURBANCE THROUGH THE EVENING...INTO THE EARLY AM HOURS
OVER NORTH CENTRAL MONTANA...HVR VICINITY AND EAST.

WEDNESDAY THROUGH FRIDAY...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 01021
    UUUUU 089/050 089/051 086/044 088/044 086 11011000000
DLN BB 054/097 057/099 057 01021
    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, 5 hours 48 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.

In the hours before

Local storm report, Aug 12, 8:30 PM MDT, 33 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
830 PM MDT TUE AUG 12 2003

TIME(MDT)  .....EVENT  LOCATION..... ST   ...EVENT/REMARKS...........
           .....COUNTY LOCATION.....

0815 PM    11 N CARTER               MT   1 INCH HAIL
08/12/03   CHOUTEAU

NNNN

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 12, 8:02 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau	43 min
Aug 12, 8:47 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Hill	58 min

Nearby

Severe Thunderstorm Warnings in Montana, 2003 Every 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.