Alert archive / Montana / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 89, NWS Great Falls, MT

August 8, 2003Fergus County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Aug 8, 2003, 5:26 PM MDT for Fergus County, Montana. It was in force for 49 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 8, 2003, 5:26 PM MDT (23:26 UTC)
Expired: Aug 8, 2003, 6:15 PM MDT
In force: 49 min
Issued by: NWS Great Falls, MT
Area: Counties, with a storm outline in the text

County Fergus 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 8, 4:35 PM MDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 11.4 hours before the alert went out and 77 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: 1701 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 17 m²/s²
0-3 km storm-relative helicity: 192 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 082326
SVRTFX
MTC027-090015-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
525 PM MDT FRI AUG 8 2003

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

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

* UNTIL 615 PM MDT

* AT 521 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 36 MILES SOUTH OF WINIFRED...OR ABOUT 11 MILES
  WEST OF LEWISTOWN...MOVING NORTH AT 35 MPH.

* THE SEVERE THUNDERSTORM WILL AFFECT...
  HIGHWAY 81 BETWEEN DENTON AND BROOKS AT 550 PM MDT 

VERY LARGE HAIL IS POSSIBLE WITH THIS SEVERE THUNDERSTORM. IF YOU ARE
IN THE PATH OF THE STORM...PUT YOUR CAR IN A GARAGE AND MOVE TO A
SUBSTANTIAL SHELTER.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM MDT
FRIDAY EVENING FOR CENTRAL MONTANA.

LAT...LON 4706 10975 4700 10948 4761 10931 4764 10976

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 8, 2:30 PM MDT, 2 hours 56 minutes earlier.

Area forecast discussion, Aug 8, 2:30 PM MDT, 2 hours 56 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST
NATIONAL WEATHER SERVICE GREAT FALLS MT
230 PM MDT FRI AUG 8 2003

.DISCUSSION...

PATTERN REMAINS ESSENTIALLY UNCHANGED WITH A DEEP UPPER LEVEL LOW OFF
THE PACIFIC NORTHWEST COAST AND RIDGING OVER THE ROCKIES. SOUTHWEST
FLOW CONTINUES OVER MY CWA...WITH OCCASIONAL DISTURBANCES MOVING OVER
AN UNSTABLE AIRMASS FOR AFTERNOON AND EVENING CONVECTION.

TONIGHT...MODELS HAVE COME INTO AGREEMENT THIS AFTERNOON...AND BRING
UPPER LEVEL ENERGY FROM SOUTHWEST MONTANA NORTHEAST OVERNIGHT.
MODELS ALSO HINT AT THE POSSIBILITY OF A MESO-SCALE COMPEX FORMING
IN CENTRAL AND EASTERN MONTANA. HAVE INCREASED POPS IN MANY LOCATIONS
TO SCATTERED FOR TONIGHT...AND WILL CONTINUE A MENTION OF POSSIBLE
SEVERE STORMS. HAVE ALSO ISSUED A FIRE WEATHER WATCH FOR FW ZONE
118...DUE TO LOW RH VALUES AND ISOLATED DRY THUNDERSTORMS.

FRIDAY THROUGH SUNDAY...DIURNAL CONVECTION DEVELOPS DURING THE
AFTERNOON AND EVENING HOURS EACH DAY. TEMPERATURES REMAIN WARM AND
WINDS LIGHT. MPJ

MONDAY THROUGH FRIDAY...UPPER RIDGE REMAINS IN PLACE OVER
CENTRAL ROCKIES THROUGH EXTENDED PERIOD. UPPER TROUGH OVER PACIFIC
NORTHWEST SENDS SEVERAL IMPULSES INTO RIDGE...FLATTENING RIDGE
SOMEWHAT AND LEAVING AREA UNDER SW FLOW ALOFT THROUGH FRIDAY. WEAK
DISTURBANCES MOVING THRU SW FLOW ALOFT WILL HELP KICK OFF AFTERNOON
AND EVENING CONVECTION...MAINLY OVER THE MOUNTAINS OF SW MT. IF
PACIFIC TROUGH INCHES EASTWARD...THERE WILL BE A BETTER CHANCE FOR
ORGANIZED CONVECTION. BUT NOT ENOUGH EVIDENCE OF THAT TO MAKE ANY
CHANGES TO THE FORECAST NOW. TEMPERATURES REMAIN AT OR ABOVE NORMAL
THROUGH THE PERIOD...WITH COOLER TEMPS TOWARDS THE NORTHWEST.

.CCF NUMBERS
GTF BU 057/090 062/093 056 14322
    UUUBU 092/060 088/058 088/054 078/055 085 1000000--00
CTB BU 053/086 054/089 052 14222
    BUBBU 085/055 084/054 084/050 077/052 080 1000000--00
HLN UU 058/091 062/093 055 14322
    UBUBB 092/058 086/056 086/051 078/053 086 2-----022--
BZN UU 050/089 053/090 056 14322
    UBBBU 092/054 086/057 086/053 080/055 089 1-0-00022--
WEY UU 040/082 047/083 050 14222
    BBBBU 083/051 076/051 076/049 077/052 083 22121111111
DLN UU 051/088 052/091 054 14211
    BBBBB 089/053 083/052 083/047 088/053 087 111122122--
HVR BU 060/093 064/093 056 14322
    BUUBU 094/063 091/062 091/059 082/057 084 00000000000
LWT BU 059/087 059/090 058 14322
    UUUUU 091/061 087/060 087/057 082/054 084 00000001100

.TFX...FIRE WEATHER WATCH FOR ISOLATED DRY LIGHTNING THIS AFTERNOON
       THROUGH THIS EVENING ZONE 118.

Hazardous weather outlook, Aug 8, 1:15 PM MDT, 4 hours 11 minutes before

MTZ008>015-044>055-090600-
HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE GREAT FALLS MT
115 PM MDT FRI AUG 8 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND SOUTHWEST
MONTANA

.DAY ONE...TODAY

ISOLATED THUNDERSTORMS WILL OCCUR THIS AFTERNOON AND EVENING. SOME
OF THESE STORMS MAY BE SEVERE...WITH DAMAGING WINDS AND HAIL. STORMS
SHOULD DEVELOP OVER EXTREME SOUTHWEST MONTANA BETWEEN 2 AND 4 PM AND
SPREAD NORTHWARD THROUGH THE AREA...REACHING HILL AND BLAINE
COUNTIES BETWEEN 8 PM AND MIDNIGHT.

FREQUENT LIGHTNING IS EXPECTED WITH THE THUNDERSTORMS. THEREFORE A
FIRE WEATHER WATCH HAS BEEN ISSUED FOR MOST OF SOUTHWEST MONTANA FOR
THIS AFTERNOON AND EVENING. REFER TO GTFRFWTFX...GTFRFWBYZ AND
GTFRFWMSO FOR MORE INFORMATION.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.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 8, 5:24 PM MDT, 2 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
524 PM MDT FRI AUG 8 2003

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

0510 PM    2 W MOORE                 MT   0.50 INCH HAIL
08/08/03   FERGUS

0515 PM    MOORE                     MT   0.50 INCH HAIL
08/08/03   FERGUS

NNNN

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.