Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 20, NWS Great Falls, MT

June 22, 2002Blaine County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jun 22, 2002, 4:19 PM MDT for Blaine 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: Jun 22, 2002, 4:19 PM MDT (22:19 UTC)
Expired: Jun 22, 2002, 5:00 PM MDT
In force: 41 min
Issued by: NWS Great Falls, MT
Area: Counties, with a storm outline in the text

County Blaine 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
Jun 22, 1:45 PM MDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 10.3 hours before the alert went out and 176 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: 5 J/kg
Mixed-layer CIN: -434 J/kg
Mixed-layer LCL: 1427 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: -14 m²/s²
0-3 km storm-relative helicity: -7 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 222219
SVRTFX
MTC005-222300-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
418 PM MDT SAT JUN 22 2002

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL BLAINE COUNTY IN NORTH CENTRAL MONTANA

* UNTIL 500 PM MDT

* AT 415 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 6 MILES NORTH OF ZURICH...OR ABOUT 11 MILES
  NORTHEAST OF CHINOOK...MOVING NORTHWEST AT 5 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
RURAL NORTHERN BLAINE COUNTY AT 440 PM MDT

THIS STORM IS CAPABLE OF PRODUCING VERY LARGE HAIL AND UP TO ONE 
INCH OF RAINFALL OVER THE NEXT HOUR.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN GREAT FALLS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 700 PM MDT
SATURDAY EVENING FOR NORTH CENTRAL MONTANA.

LAT...LON 4855 10900 4870 10884 4890 10919 4870 10941

$$

BRUSDA

NNNN

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 Jun 22, 3:00 PM MDT, 1 hour 19 minutes earlier.

Area forecast discussion, Jun 22, 3:00 PM MDT, 1 hour 19 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
300 PM MDT SAT JUN 22 2002

.SHORT TERM...EXPECT SHOWERS AND THUNDERSTORMS TO CONTINUE TO
DEVELOP THIS AFTERNOON INTO THE EARLY EVENING AND BECOME WIDESPREAD
AS AN UPPER LEVEL TROUGH MOVES OVER THE CWA. PLENTY MOISTURE IS
AVAILABLE WITH DEW POINTS IN THE 50S. ATMOSPHERE HAS BECOME UNSTABLE
ACROSS THE CWA EXCEPT FOR THE SOUTHWEST ZONES. THERE WILL BE ENOUGH
INSTABILITY FOR SEVERE THUNDERSTORMS HOWEVER...WITH A WEAK SHEAR
ENVIRONMENT THE SEVERE THUNDERSTORMS WILL BE ISOLATED AND MAINLY
PULSE-TYPE STORMS. THE THREAT FOR SEVERE WEATHER WILL END THIS
EVENING WITH LOSS OF DAYTIME HEATING. SHOWERS AND EMBEDDED
THUNDERSTORMS WILL THEN CONTINUE FOR MUCH OF THE NIGHT.

WILL SEE SOME SHOWERS AND ISOLATED THUNDERSTORMS LINGER MAINLY ACROSS
THE EASTERN ZONES ON SUNDAY. THERE WILL ALSO BE ENOUGH INSTABILITY
OVER THE SOUTHWESTERN ZONES FOR SCATTERED THUNDERSTORMS TO DEVELOP
DURING THE AFTERNOON ON SUNDAY AND ON MONDAY. TEMPERATURES WILL COOL
INTO THE 70S AND LOWER 80S SUNDAY BUT THEN REBOUND INTO THE 80S
MONDAY AS THE RIDGE REBUILDS OVER THE REGION. MEIER

.EXTENDED...SOME DIFFERENCES IN THE CURRENT MODEL RUN FROM
YESTERDAYS RUN. MODELS MAINTAIN A GENERAL RIDGE PATTERN OVER THE
AREA WEDNESDAY BUT HAVE INTRODUCED LOW PRESSURE ALOFT OVER THE
SOUTHWEST. THE MRF IS MORE PRONOUNCED WITH THIS FEATURE BUT THE AVN
ALSO HINTS AT ITS EXISTENCE. MODELS CONTINUE TO MAINTAIN SOUTHWEST
FLOW ALOFT THURSDAY AND FRIDAY WITH ENOUGH INSTABILITY FOR A CHANCE
OF SHOWERS. THE UPPER RIDGE BEGINS TO REBUILD OVER THE SOUTHWEST
SATURDAY WITH CONDITIONS BECOMING DRY AND STABLE. TEMPERATURES WILL
REMAIN WARM THROUGH THE PERIOD WITH LITTLE VARIATION.

.CCF NUMBERS
GTF EB 056/078 053/083 056 12730
    BBBBB 086/055 088/055 090/055 090/055 090 11112222211
CTB BB 055/076 050/080 052 12620
    BBBBB 083/052 086/050 086/050 087/050 087 11112222211
HLN BB 055/080 055/086 058 12621
    BBBBB 090/055 090/055 090/055 090/055 090 22112222211
BZN BB 052/078 050/082 050 12531
    BBBBB 086/050 088/050 088/050 088/050 088 33112222211
WEY BB 042/070 040/076 040 12531
    BBBBB 080/040 078/040 079/040 079/040 079 33112222211
DLN BB 050/078 050/083 050 12431
    BBBBB 088/048 088/048 088/048 088/048 088 33112222211
HVR TB 060/080 057/088 058 12741
    BBBBB 090/058 090/058 090/058 090/058 090 11112222221
LWT TB 055/076 052/082 052 12741
    BBBBB 085/052 087/053 087/053 087/053 087 11112222221=

.TFX...FLOOD WARNING CONTINUES FOR GLACIER COUNTY
       RIVER STATEMENT FOR NORTHWEST ZONES...SEE FGUS85 KTFX...
       RVSTFX.

In the hours before

Local storm report, Jun 22, 10:59 AM MDT, 5 hours 20 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1059 AM MDT SAT JUN 22 2002

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

0720 PM    BOULDER                   MT   1 INCH HAIL
06/21/02   JEFFERSON                      REPORTED BY BOULDER SHERIFF

0752 PM    SILVER CITY               MT   62 MPH TSTM GUST
06/21/02   LEWIS  AND  CLARK

0815 PM    20 SE CASCADE             MT   60 MPH TSTM GUST
06/21/02   CASCADE                        ESTIMATED. 0.47 INCHES OF
                                          RAIN IN 10 MINUTES. 1/4
                                          INCH HAIL.

0815 PM    SILVER CITY               MT   65 MPH TSTM GUST
06/21/02   LEWIS  AND  CLARK              ESTIMATED

0930 PM    7 S NEIHART               MT   0.75 INCH HAIL
06/21/02   CASCADE                        HAIL COVERED THE GROUND

0930 PM    14 E JEFFERSON CITY       MT   60 MPH TSTM GUST
06/21/02   JEFFERSON                      ESTIMATED

1000 PM    3 N MONARCH               MT   0.75 INCH HAIL
06/21/02   CASCADE

NNNN

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 21, 7:39 PM MDT	Severe Thunderstorm Warning	TFX	Jefferson	36 min
Jun 21, 7:45 PM MDT	Severe Thunderstorm Warning	TFX	Jefferson	30 min
Jun 21, 7:59 PM MDT	Severe Thunderstorm Warning	TFX	Broadwater	31 min
Jun 21, 8:03 PM MDT	Severe Thunderstorm Warning	TFX	Cascade	42 min
Jun 21, 8:07 PM MDT	Severe Thunderstorm Warning	TFX	Lewis and Clark	23 min
Jun 21, 8:08 PM MDT	Severe Thunderstorm Warning	TFX	Cascade	37 min
Jun 21, 8:28 PM MDT	Severe Thunderstorm Warning	TFX	Meagher	32 min
Jun 21, 8:58 PM MDT	Severe Thunderstorm Warning	TFX	Meagher	47 min
Jun 21, 9:11 PM MDT	Severe Thunderstorm Warning	TFX	Cascade, Meagher	64 min
Jun 21, 9:57 PM MDT	Severe Thunderstorm Warning	TFX	Judith Basin	48 min
Jun 22, 2:49 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	26 min
Jun 22, 3:20 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	55 min

Nearby

Severe Thunderstorm Warnings in Montana, 2002 Every severe thunderstorm warning in 2002

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.