Alert archive / Montana / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 2, NWS Great Falls, MT

June 2, 2012Fergus County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jun 2, 2012, 4:35 PM MDT for Fergus County, Montana. It was in force for 22 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 2, 2012, 4:35 PM MDT (22:35 UTC)
Expired
Jun 2, 2012, 4:57 PM MDT
In force
22 min
Issued by
NWS Great Falls, MT
Area
Storm-based polygon

County Fergus County, MT

The radar

The Billings radar (KBLX), 137 km from the middle of the area, began a volume at 22:38 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.

What was reported inside it

TimeReportWhereRemark
Jun 2, 4:36 PM MDTHAIL 12 W Forestgrove, MTHAIL UP TO QUARTER SIZE JUST ENDING.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jun 2, 2:10 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 10.6 hours before the alert went out and 146 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 2012-06-02Temperature 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 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 12:00Z on 2012-06-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 square meters per square second.19395878Sfc1 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
1977 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
66 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.

029 
WUUS55 KTFX 022235
SVRTFX
MTC027-022315-
/O.NEW.KTFX.SV.W.0002.120602T2235Z-120602T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
435 PM MDT SAT JUN 2 2012

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

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

* UNTIL 515 PM MDT.

* AT 433 PM MDT...TRAINED WEATHER SPOTTERS REPORTED A SEVERE
  THUNDERSTORM 13 MILES WEST OF GRASS RANGE...MOVING EAST AT 30 MPH.

* LOCATIONS IN THE WARNING INCLUDE GRASS RANGE.

HAIL TO THE SIZE OF QUARTERS AND WIND GUSTS TO 60 MPH ARE LIKELY WITH
THIS STORM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM MDT
SATURDAY EVENING FOR SOUTHWEST MONTANA.

&&

LAT...LON 4676 10862 4682 10912 4705 10919 4731 10861
      4726 10861 4726 10867 4724 10871 4719 10870
      4717 10873 4711 10873 4710 10861
TIME...MOT...LOC 2235Z 250DEG 25KT 4700 10905

$$
1 follow-up statement
633 
WWUS55 KTFX 022257
SVSTFX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
457 PM MDT SAT JUN 2 2012

MTC027-022307-
/O.CAN.KTFX.SV.W.0002.000000T0000Z-120602T2315Z/
FERGUS MT-
457 PM MDT SAT JUN 2 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL FERGUS COUNTY IS
CANCELLED...

NATIONAL WEATHER SERVICE RADAR INDICATED THAT THE SEVERE THUNDERSTORM
THAT PROMPTED THE WARNING HAD WEAKENED AND WAS NO LONGER SEVERE...
THUS THE WARNING HAS BEEN CANCELLED.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM MDT
SATURDAY EVENING FOR CENTRAL MONTANA.

LAT...LON 4676 10862 4682 10912 4705 10919 4731 10861
      4726 10861 4726 10867 4724 10871 4719 10870
      4717 10873 4711 10873 4710 10861
TIME...MOT...LOC 2257Z 250DEG 25KT 4705 10884

$$

BRUSDA

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 2, 12:05 PM MDTSpecial Weather StatementTFXBeaverhead55 min
Jun 2, 12:45 PM MDTSpecial Weather StatementTFXBeaverhead60 min
Jun 2, 1:38 PM MDTSpecial Weather StatementTFXMadison67 min
Jun 2, 2:23 PM MDTSpecial Weather StatementTFXLewis and Clark22 min
Jun 2, 2:56 PM MDTSpecial Weather StatementTFXCascade49 min
Jun 2, 4:28 PM MDTSpecial Weather StatementTFXFergus47 min
Jun 2, 4:49 PM MDTSpecial Weather StatementTFXGallatin41 min
Jun 2, 4:55 PM MDTSpecial Weather StatementTFXJudith Basin65 min
Jun 2, 5:50 PM MDTSevere Thunderstorm WarningTFXBlaine, Chouteau, Fergus70 min

Nearby

Severe Thunderstorm Warnings in Montana, 2012Every severe thunderstorm warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.