Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 81, NWS Great Falls, MT

July 26, 2002Blaine County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jul 26, 2002, 7:55 PM MDT for Blaine County, Montana. It was in force for 50 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
Jul 26, 2002, 7:55 PM MDT (01:55 UTC)
Expired
Jul 26, 2002, 8:45 PM MDT
In force
50 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 nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 1.9 hours before the alert went out and 177 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 00:00Z on 2002-07-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 30 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 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 00:00Z on 2002-07-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 33 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
30 J/kg
Mixed-layer CIN
-146 J/kg
Mixed-layer LCL
2271 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
33 m²/s²
0-3 km storm-relative helicity
96 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.

511 
WUUS55 KTFX 270155
SVRTFX
MTC005-270245-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
754 PM MDT FRI JUL 26 2002

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

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

* UNTIL 845 PM MDT

* AT 746 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 9 MILES NORTHWEST OF ZURICH...OR ABOUT 8 MILES
  NORTHEAST OF CHINOOK...MOVING SOUTHEAST AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  3 MILES NORTHEAST OF ZURICH AT 815 PM MDT

VERY LARGE HAIL TO ONE INCH IN DIAMETER 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.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS AS THEY
MAY BE WASHED OUT. WATER LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO
RISE...THEREFORE SEEK HIGHER GROUND IF THREATENED BY FLOOD WATERS.

STRONG WIND GUSTS TO 60 MPH ARE ALSO POSSIBLE.

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 4875 10905 4864 10922 4847 10899 4862 10878

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 Jul 26, 3:15 PM MDT, 4 hours 40 minutes earlier.

Area forecast discussion, Jul 26, 3:15 PM MDT, 4 hours 40 minutes before
SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
315 PM MDT FRI JUL 26 2002

.SHORT TERM...SURFACE COLD FRONT OVER PACIFIC NORTHWEST WITH
ASSOCIATED UPPER LEVEL TROUGH OF LOW PRESSURE TO SWEEP ACROSS
AREA TONIGHT AND SATURDAY. AVN MODEL IS FASTER AND MORE IN
LINE WITH UKMET/CAN MODELS THAN THE ETA. SCATTERED SHOWERS
AND THUNDERSTORMS WERE DEVELOPING ACROSS CENTRAL AND SW
MT THIS AFTERNOON. MAIN CONCERN WITH CONVECTION IS STRONG
GUSTY WINDS AS AMS IS DRY AT THE LOW LEVELS. SURFACE FRONT
COLD FRONT SHOULD MOVE THROUGH KGTF AROUND MIDNIGHT AND WILL
KEEP SCT POPS SW AND LOW POPS CENTRAL MT THROUGH SATURDAY AS
UPPER TROUGH SWEEPS THROUGH WITH CYCLONIC NORTHWEST FLOW ALOFT
AND COLD AIR ADVECTION ALOFT FOR INCREASED INSTABILITIES.
SUNDAY AND MONDAY WILL BE DRY WITH TEMPERATURES A BIT WARMER
UNDER A WEST-NORTHWEST ZONAL FLOW. WILLIAMSON DC

.EXTENDED...MEDIUM RANGE MODELS FALLING MORE INTO LINE TODAY.
EXTENDED AVN BACKING OFF FROM UPPER RIDGE OVER STATE TO MORE OF A
ZONAL FLOW FOR TUESDAY AND WEDNESDAY. A WEAK DISTURBANCE MOVES
THROUGH SOUTHWEST MONTANA ON WEDNESDAY FOR A CHANCE OF
AFTERNOON/EVENING SHOWERS/THUNDERSTORMS THERE AND OVER THE MOUNTAINS
OF CENTRAL MONTANA. AN UPPER TROUGH DIGS OVER THE PACIFIC NORTHWEST
FOR THURSDAY AND FRIDAY...BRINGING A MORE MOIST AND UNSTABLE
SOUTHWEST FLOW ALOFT. A STRONGER DISTURBANCE MOVES THROUGH
SOUTHWEST AND CENTRAL MONTANA THURSDAY FOR A CHANCE OF ACTIVITY
AGAIN. THE FLOW IS NOT AS MOIST ON FRIDAY WITH ONLY A WEAK
DISTURBANCE MOVING OVERHEAD...FOR ONLY A SLIGHT CHANCE OF ACTIVITY.
WITH THE SCATTERED ACTIVITY...TEMPERATURES WILL ONLY SLIGHTLY ABOVE
NORMAL THROUGH THE PERIOD...WITH HIGHS GENERALLY IN THE 80S AND
LOWS IN THE UPPER 40S AND 50S.  COULSTON

.CCF NUMBERS
GTF EB 058/078 054/080 054 20322
   UUBBB 082/052 085/055 088/053 085/052 088 10000022221
CTB EB 054/074 050/078 051 20322
   UUUBB 079/049 082/052 085/050 082/050 085 10000001111
HLN EB 055/077 052/080 052 20332
   UUBBB 084/051 087/053 089/055 087/055 090 10000022321
BZN EB 051/078 050/080 051 20332
   UUBBB 081/049 084/051 086/053 085/053 087 10000033442
WEY EB 044/077 040/075 042 20332
   UUBBB 075/042 080/043 082/044 082/044 082 10000033442
DLN EB 052/076 050/078 050 20222
   UUBBB 080/051 085/052 088/052 086/052 088 10000022332
HVR EB 060/080 055/080 052 20322
   UUUBB 084/053 088/055 091/057 091/057 091 10000000221
LWT EB 056/075 049/076 050 20332
   UUBBB 078/051 083/052 087/055 087/055 087 10000022332

.TFX...NONE.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 27, 12:00 PM MDTSevere Thunderstorm WarningTFXGallatin45 min

Nearby

Severe Thunderstorm Warnings in Montana, 2002Every 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.