Alert archive / Montana / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 75, NWS Great Falls, MT

August 5, 2003Jefferson County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Aug 5, 2003, 6:17 PM MDT for Jefferson County, Montana. It was in force for 28 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 5, 2003, 6:17 PM MDT (00:17 UTC)
Expired: Aug 5, 2003, 6:45 PM MDT
In force: 28 min
Issued by: NWS Great Falls, MT
Area: Counties, with a storm outline in the text

County Jefferson County, MT

The radar

The Great Falls radar (KTFX), 165 km from the middle of the area, began a volume at 00:16 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.

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, 0.3 hours before the alert went out and 187 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: 169 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 3292 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 28 m²/s²
0-3 km storm-relative helicity: 137 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

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

110 
WUUS55 KTFX 060017
SVRTFX
MTC043-060045-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
615 PM MDT TUE AUG 5 2003

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN JEFFERSON COUNTY IN SOUTHWEST MONTANA

* UNTIL 645 PM MDT

* AT 610 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER SOUTHEASTERN JEFFERSON COUNTY...OR ABOUT
  20 MILES SOUTHEAST OF BOULDER...MOVING NORTHEAST AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL REMAIN OVER...
  RURAL SOUTHERN AND EASTERN JEFFERSON COUNTY

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

LAT...LON 4603 11201 4619 11180 4606 11178 4606 11166
          4598 11166 4590 11177 4581 11192

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 5, 2:45 PM MDT, 3 hours 32 minutes earlier.

Area forecast discussion, Aug 5, 2:45 PM MDT, 3 hours 32 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST
NATIONAL WEATHER SERVICE GREAT FALLS MT
245 PM MDT TUE AUG 5 2003

.DISCUSSION...

TONIGHT THROUGH WEDNESDAY...STRONG RIDGE OVER 4 CORNERS REGION WITH
AXIS NORTHWARD ACROSS ERN MONTANA AND TROUGH OVER W COAST WILL BRING
A MOIST AND UNSTABLE SOUTHWEST FLOW ALOFT. UPPER LEVEL DYNAMICS WILL
ENHANCE POTENTIAL FOR THUNDERSTORM ACTIVITY...PRIMARILY ACROSS SW
MONTANA. SOME OF THESE THUNDERSTORMS MAY BECOME SEVERE...ESPECIALLY
WEDNESDAY AFTERNOON ACROSS THE SW AND WEDNESDAY EVENING OVER NORTH
CENTRAL MT. TEMPERATURES WILL WARM INTO THE 90S ON WEDNESDAY...THUS
THE AIRMASS WILL BECOME QUITE UNSTABLE.

THURSDAY THROUGH SATURDAY...SOUTHWEST FLOW ALOFT CONTINUES.
AFTERNOON AND EVENING CONVECTION A POSSIBILITY EACH DAY WITH NO
ORGANIZED STORMS ANTICIPATED. TEMPS WILL REMAIN ABOVE SEASONAL
AVERAGES, BUT NOT TOO HOT FOR THIS TIME OF YEAR.

SUNDAY AND MONDAY...SUNDAY REMAINS WARM WITH ONLY ISOLATED POPS
BUT A SURFACE LOW DEVELOPS OVER ERN MONTANA AND SRN SASKATCHEWAN
SUNDAY NIGHT CAUSING SOME GUSTY WEST WINDS. THIS DOES BEAR WATCHING
FOR FIRE WEATHER ISSUES. MONDAY LOOKS DRY AND CONTINUED WARMER THAN
AVERAGE.

.CCF NUMBERS
GTF BB 059/094 057/092 056 05223
    BBUUU 088/055 087/057 088/055 088/060 088 22222110000
CTB BB 055/089 053/090 054 05323
    BBUBU 082/053 084/053 083/052 086/055 084 11222--0000
HLN BB 061/092 058/093 059 05332
    BBUUU 090/055 090/056 090/055 087/058 086 22222--0000
BZN BB 055/093 051/092 053 05332
    BBUUU 089/052 089/054 088/055 090/058 086 22222110000
WEY BB 050/083 047/079 047 05222
    BBBBU 081/047 082/051 082/050 082/051 076 22222220000
DLN BB 052/087 052/088 054 05332
    BBBUU 088/052 087/054 086/053 085/054 083 22222110000
HVR BB 061/095 063/095 060 05324
    BBUBU 091/059 092/060 091/056 089/063 091 01222110000
LWT BB 058/091 060/093 058 05223
    BBUUU 086/056 086/058 084/057 091/061 087 11222220000

.TFX...NONE.

Hazardous weather outlook, Aug 5, 6:30 AM MDT, 11 hours 47 minutes before

MTZ008>015-044>055-060010-
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREAT FALLS MT
630 AM MDT TUE AUG 5 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND SOUTHWEST MONTANA

.DAY ONE...TODAY

THERE IS A POSSIBILITY OF THUNDERSTORMS ACROSS NORTH CENTRAL
AND SOUTHWEST MONTANA TODAY AND TONIGHT. SOME OF THE STORMS COULD
BECOME SEVERE WITH HAIL AND DAMAGING WINDS THE MAIN SEVERE WEATHER
THREAT. THUNDERSTORMS ARE EXPECTED TO IMPACT WESTERN PARTS OF THE
AREA TODAY WITH EASTERN SECTIONS OF THE REGION EXPECTED TO SEE
THUNDERSTORMS LATER THIS AFTERNOON AND TONIGHT.

NO WATCHES, WARNINGS, OR ADVISORIES ARE CURRENTLY IN EFFECT BUT
YOU SHOULD REMAIN COGNIZANT OF WEATHER UPDATES THROUGH WWW.WEATHER.GOV
...NOAA WEATHER RADIO OR YOUR FAVORITE MEDIA OUTLET TODAY AND TONIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THERE IS A CHANCE OF THUNDERSTORMS WEDNESDAY AND THURSDAY ACROSS
NORTH CENTRAL AND SOUTHWEST MONTANA. SOME OF THESE STORMS COULD
BECOME SEVERE.

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.

Issued	Product	Office	Counties	Lasted
Aug 5, 6:06 PM MDT	Severe Thunderstorm Warning	TFX	Madison	39 min
Aug 6, 4:45 PM MDT	Severe Thunderstorm Warning	TFX	Lewis and Clark	45 min
Aug 6, 4:54 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	36 min
Aug 6, 5:06 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	39 min
Aug 6, 5:09 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	51 min
Aug 6, 5:35 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	25 min
Aug 6, 5:44 PM MDT	Severe Thunderstorm Warning	TFX	Lewis and Clark	46 min
Aug 6, 5:45 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	30 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; radar from the NEXRAD Level II archive.