Alert archive / Montana / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 3, NWS Great Falls, MT

April 23, 2003Toole County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Apr 23, 2003, 5:04 PM MDT for Toole County, Montana. It was in force for 41 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
Apr 23, 2003, 5:04 PM MDT (23:04 UTC)
Expired
Apr 23, 2003, 5:45 PM MDT
In force
41 min
Issued by
NWS Great Falls, MT
Area
Counties, with a storm outline in the text

County Toole County, MT

The radar

The Great Falls radar (KTFX), 136 km from the middle of the area, began a volume at 23:08 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 12:00Z, 11.1 hours before the alert went out and 163 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 12:00Z on 2003-04-23Temperature 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 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 12:00Z on 2003-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 110 square meters per square second.1939Sfc1 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
1600 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
110 m²/s²
0-3 km storm-relative helicity
194 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.

884 
WUUS55 KTFX 232304
SVRTFX
MTC101-232345-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
504 PM MDT WED APR 23 2003

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

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

* UNTIL 545 PM MDT

* AT 500 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 8 MILES SOUTHEAST OF KEVIN...OR ABOUT 10 MILES
  NORTH OF SHELBY...MOVING WEST AT 10 MPH.

* THE SEVERE THUNDERSTORM WILL BE...
  7 MILES SOUTH OF KEVIN AT 515 PM MDT
  AND JUST NORTH OF ETHRIDGE BY 525 PM MDT

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 4858 11171 4876 11174 4879 11214 4849 11215

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 Apr 23, 2:20 PM MDT, 2 hours 44 minutes earlier.

Area forecast discussion, Apr 23, 2:20 PM MDT, 2 hours 44 minutes before
SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
220 PM MDT WED APR 23 2003

.SHORT TERM...THUNDERSTORMS POPPING ONCE AGAIN OVER MY CWA. ACTIVITY
WILL DIE DOWN SOMEWHAT AFTER SUNSET BUT PROBABLY WILL NOT CEASE
ALTOGHER...ESPECIALLY OVER HIGHER TERRAIN. A SIMILAR SCENARIO WILL
UNFOLD TOMORROW...WITH CONVECTION INITIATING OVER THE MOUNTAINS LATE
IN THE MORNING AND THEN SOME CELLS SURVIVING OVER THE PLAINS IN THE
AFTERNOON. HIGH TEMPS TOMORROW SHOULD ALSO BE SIMILAR TO TODAY OVER
THE PLAINS. THERE WILL BE A PRONOUNCED WARM-UP OVER THE SOUTHWEST
WHERE THE SUN WILL SHINE MORE THAN IT DID TODAY. ATTENTION THEN TURNS
TO A BROAD UPPER LOW AND ASSOCIATED COLD FRONT OFF THE PACIFIC COAST.
THE UPPER LOW WILL BRING A MOIST AND UNSTABLE SOUTHWEST FLOW INTO
CENTRAL AND SOUTHWEST MONTANA FRIDAY. THIS COULD EVOLVE INTO A
WIDESPREAD OUTBREAK OF THUNDERSTORMS...WITH A SEVERE CELL OR TWO IN
THE SOUTHWEST. BUT SOME UNCERTAINTY REMAINS. HAVE ELECTED TO
RAISE POPS MAINLY FOR FRIDAY AFTERNOON. POMEROY

.EXTENDED...LITTLE CHANGE IN THE GOING FORECAST. MODELS IN
GOOD AGREEMENT ON GENERAL TRENDS. UPPER LOW NEAR PAC NW COAST EARLY
SAT MOVES E/NE THROUGH AREA OVER THE WEEKEND WITH AREA COMING UNDER
THE INFLUENCE OF STILL ANOTHER PACIFIC UPPER TROUGH EARLY NEXT WEEK.
MODELS IN BETTER AGREEMENT FOR MONDAY.  ALTHOUGH AN UPPER RIDGE TRIES
TO DEVELOP OVER CWA ON MONDAY...LEFT POPS AS IS AS SW FLOW OVER SW
MT TO PICK UP AGAIN AND SPREAD MOISTURE TUESDAY NORTHWARD TUESDAY
AND WEDNESDAY. CAMP

.CCF NUMBERS
GTF ET 042/070 042/059 035 19433
    EEBER 052/032 050/032 053/034 058/034 058 54442223335
CTB BT 040/067 041/054 033 19334
    NEBEE 046/030 046/028 052/032 055/032 055 53332223333
HLN ET 042/067 044/059 035 19534
    EEBER 052/032 050/031 056/036 059/036 059 64442233325
BZN ET 042/067 040/058 033 19633
    EEBER 050/030 049/028 054/033 058/033 058 64442233346
WEY ET 033/057 029/047 027 19844
    WEBEO 038/026 036/020 045/025 047/025 047 75552244466
DLN ET 042/064 040/051 032 19634
    EEBER 046/027 045/027 051/032 054/032 054 64442233356
HVR BB 044/071 042/064 036 19222
    EEBEE 058/032 049/030 058/032 062/032 062 43332223343
LWT EB 041/067 040/060 034 19522
    EEBER 052/030 046/030 051/034 056/034 056 54442223356

.TFX...NONE.
Hazardous weather outlook, Apr 23, 6:39 AM MDT, 10 hours 25 minutes before
MTZ008>015-044>055-240010-
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREAT FALLS MT
64 AM MDT WED APR 23 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND SOUTHWEST
MONTANA

.DAY ONE...TODAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

NO WATCHES, WARNINGS, OR ADVISORIES CURRENTLY IN EFFECT

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

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.

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; radar from the NEXRAD Level II archive.