Alert archive / Montana / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 4, NWS Great Falls, MT

April 25, 2003Fergus County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Apr 25, 2003, 3:58 PM MDT for Fergus County, Montana. It was in force for 32 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 25, 2003, 3:58 PM MDT (21:58 UTC)
Expired: Apr 25, 2003, 4:30 PM MDT
In force: 32 min
Issued by: NWS Great Falls, MT
Area: Counties, with a storm outline in the text

County Fergus County, MT

The radar

The Billings radar (KBLX), 176 km from the middle of the area, began a volume at 22:01 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, 10.0 hours before the alert went out and 140 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: 1625 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 40 m²/s²
0-3 km storm-relative helicity: 55 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.

457 
WUUS55 KTFX 252158
SVRTFX
MTC027-252230-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
356 PM MDT FRI APR 25 2003

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

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

* UNTIL 430 PM MDT

* AT 355 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER NORTHEAST FERGUS COUNTY...OR ABOUT 5
  MILES NORTHEAST OF ROY...MOVING NORTHEAST AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
RURAL EASTERN FERGUS COUNTY THROUGH 430 PM MDT

SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE
WARNING. PREPARE TO MOVE TO A PLACE OF SAFETY IN A STURDY STRUCTURE
SUCH AS A BASEMENT OR SMALL INTERIOR ROOM IF A TORNADO IS SPOTTED.

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH YOU SHOULD PREPARE 
FOR DAMAGING WINDS IN EXCESS OF 55 MPH...LARGE HAIL...AND DEADLY 
LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...PREFERABLY 
INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

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 4748 10897 4723 10876 4736 10840 4762 10857

$$
10

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 25, 2:30 PM MDT, 1 hour 28 minutes earlier.

Area forecast discussion, Apr 25, 2:30 PM MDT, 1 hour 28 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
230 PM MDT FRI APR 25 2003

.SHORT TERM...TONIGHT AN UPPER LEVEL DISTURBANCE WILL MOVE NORTH
FROM SOUTHWEST TO NORTH CENTRAL MONTANA. THIS WILL ALLOW FOR A BAND
OF PRECIPITATION TO MOVE NORTH ACROSS THE AREA. SOME AREAS MAY SEE
UP TO A QUARTER OF AN INCH OF PRECIP AS IT MOVES THROUGH. THE PRECIP
WILL COME TO AN END AFTER MIDNIGHT...BUT THEN REDEVELOP TOWARDS DAY
BREAK OVER THE SOUTHWEST. EXPECT SNOW LEVELS TO LOWER TO 5000 FEET
OVER THE SOUTWEST...AS MUCH COOLER AIR MOVES IN. FOR SATURDAY...
RAIN AND MOUNTAIN SNOW WILL BE LIKELY ACROSS MUCH OF THE REGION...AS
AN UPPER LEVEL DISTURBANCE MOVES EAST ACROSS THE CWA. TEMPERATURES
WILL BE ABOUT 10 DEGREES COOLER THAN TODAY AS WELL. BRUSDA

ON SUNDAY THE SURFACE LOW TO THE NORTH OF CWA
CONTINUES TO PULL OFF TO THE EAST AS A SURFACE HIGH BUILDS IN
OVER THE SW. UPPER RIDGE BUILDS OVER CWA SO WILL DROP POPS OVER
MUCH OF THE AREA FOR EARLY SUNDAY AND SUNDAY AFTERNOON. EXPECT SW TO
S FLOW ALOFT TO START SO WENT WITH CHANCE OF SHOWERS SUNDAY
NIGHT. ATMOSPHERE BECOMES UNSTABLE IN SW FLOW ALOFT AND EXPECT
MORE SCATTERED SHOWERS/THUNDERSTORMS. TIMING AGAIN WILL BE THE
PROBLEM. LOOKS LIKE GFS CONTINUES TO BE THE FASTER OF THE MODELS SO
LEFT POPS IN GOING FORECAST AS WAS. LATEST GFS TEMPERATURES CONTINUE
TO BE COOLER THAN GRIDS. AM NOT BUYING INTO THEM AS YET. ANY SUN
DURING BREAKS IN THE CLOUDS WILL GET TEMPS INTO THE 50S QUITE EASILY.
OVERALL TREND IS FOR CLOUDINESS AND COOLER WITH SCATTERED SHOWERS.
CAMP

.EXTENDED...FOR THURSDAY AND FRIDAY...EXPECT SCATTERED SHOWERS AND
THUNDERSTORMS TO CONTINUE...AS AN UPPER LEVEL LOW MOVES INTO
SOUTHERN IDAHO. THE HIGHEST CHANCES WILL BE IN THE SOUTWEST...WITH
THE LOWEST CHANCES NEAR THE CANADIAN BORDER. EXPECT TEMPERATURES TO
BE NEAR TO SLIGHTLY BELOW NORMAL ON THURSDAY AND FRIDAY. BRUSDA

.CCF NUMBERS
GTF TW 035/051 033/056 030 17863
    BEEEE 053/034 056/034 058/033 056/036 059 22223333333
CTB TW 033/049 030/053 028 17663
    BEEEE 050/030 053/032 055/031 053/034 056 21113333333
HLN TW 035/051 034/055 031 17863
    EEEEE 056/036 059/036 059/035 057/038 060 23333333333
BZN TW 036/052 033/056 028 17863
    EEEEE 054/033 058/033 058/032 056/035 059 23333333333
WEY WO 026/039 022/043 018 17963
    EEEEE 045/025 048/025 048/024 046/027 049 24443344444
DLN WO 038/047 030/053 027 17963
    EEEEE 051/032 054/032 054/031 052/032 055 23333333333
HVR TW 037/054 032/052 030 17865
    BBEEE 055/030 061/032 062/031 060/034 062 21112222222
LWT TW 036/052 032/053 028 17863
    BEEEE 051/032 056/034 058/033 056/034 059 22223333333

.TFX...NONE.

Hazardous weather outlook, Apr 25, 6:45 AM MDT, 9 hours 13 minutes before

MTZ008>015-044>055-260010-
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREAT FALLS MT
645 AM MDT FRI APR 25 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...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.

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 25, 2:43 PM MDT	Tornado Warning	TFX	Fergus	32 min
Apr 25, 2:45 PM MDT	Tornado Warning	TFX	Fergus	30 min
Apr 25, 3:27 PM MDT	Tornado Warning	TFX	Fergus	33 min
Apr 25, 5:10 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	35 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.