Alert archive / Montana / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 9, NWS Great Falls, MT

June 9, 2021Chouteau County, Hill County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jun 9, 2021, 9:04 PM MDT for Chouteau County, Hill County, Montana. It was in force for 26 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 9, 2021, 9:04 PM MDT (03:04 UTC)
Expired: Jun 9, 2021, 9:30 PM MDT
In force: 26 min
Issued by: NWS Great Falls, MT
Area: Storm-based polygon
Hail: 1.5 in
Wind: 60.0 mph

Counties Chouteau County, MT, Hill County, MT

The radar

The Great Falls radar (KTFX), 147 km from the middle of the area, began a volume at 03:04 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

Time	Report	Where	Remark
Jun 9, 9:12 PM MDT	HAIL 2	7 Ene Big Sandy, MT	PICTURES FROM A SOCIAL MEDIA POST SHOWING 1.5 TO 2 INCH HAIL REPORTED NEAR CENTENNIAL MOUNTAIN AREA.

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.

Issued	Product	Office	Lasted
Jun 9, 6:42 PM MDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 3.1 hours before the alert went out and 103 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: 22 J/kg
Mixed-layer CIN: -195 J/kg
Mixed-layer LCL: 1287 m above ground
0-6 km bulk shear: 71 kt
0-1 km storm-relative helicity: 12 m²/s²
0-3 km storm-relative helicity: 408 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

710 
WUUS55 KTFX 100304
SVRTFX
MTC015-041-100330-
/O.NEW.KTFX.SV.W.0009.210610T0304Z-210610T0330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Great Falls MT
904 PM MDT Wed Jun 9 2021

The National Weather Service in Great Falls has issued a

* Severe Thunderstorm Warning for...
  Southeastern Hill County in north central Montana...
  Northeastern Chouteau County in north central Montana...

* Until 930 PM MDT.

* At 903 PM MDT, a severe thunderstorm was located 9 miles south of
  Big Sandy, moving northeast at 40 mph.

  HAZARD...Ping pong ball size hail and 60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Expect 
           wind damage to roofs, siding, and trees.

* Locations impacted include...
  Azure, Parker School, Agency, Sangrey, St. Pierre, Boneau and Rocky
  Boy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and deadly cloud to ground
lightning. Seek shelter inside a well-built structure. Stay away from
windows.

&&

LAT...LON 4825 10955 4823 10955 4822 10953 4812 10953
      4790 11005 4804 11025 4840 10982
TIME...MOT...LOC 0303Z 224DEG 35KT 4805 11006 

HAIL...1.50IN
WIND...60MPH
 
$$

Kredensor

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 9, 6:18 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	42 min
Jun 9, 6:55 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	35 min
Jun 9, 7:08 PM MDT	Special Weather Statement	TFX	Fergus	22 min
Jun 9, 7:19 PM MDT	Special Weather Statement	TFX	Teton	56 min
Jun 9, 7:26 PM MDT	Special Weather Statement	TFX	Fergus	34 min
Jun 9, 7:28 PM MDT	Special Weather Statement	TFX	Judith Basin	32 min
Jun 9, 7:36 PM MDT	Special Weather Statement	TFX	Fergus	24 min
Jun 9, 7:53 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Fergus	37 min
Jun 9, 7:57 PM MDT	Special Weather Statement	TFX	Hill	33 min
Jun 9, 8:04 PM MDT	Special Weather Statement	TFX	Judith Basin	26 min
Jun 9, 8:19 PM MDT	Special Weather Statement	TFX	Teton	26 min
Jun 9, 8:28 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Judith Basin	32 min
Jun 9, 8:31 PM MDT	Special Weather Statement	TFX	Chouteau	29 min
Jun 9, 8:42 PM MDT	Severe Thunderstorm Warning	TFX	Blaine, Fergus	33 min
Jun 9, 8:45 PM MDT	Special Weather Statement	TFX	Petroleum	30 min
Jun 9, 8:48 PM MDT	Special Weather Statement	TFX	Hill	27 min
Jun 9, 8:57 PM MDT	Special Weather Statement	TFX	Blaine	18 min
Jun 9, 9:09 PM MDT	Severe Thunderstorm Warning	TFX	Blaine, Fergus	21 min
Jun 9, 9:18 PM MDT	Special Weather Statement	TFX	Toole	42 min
Jun 9, 9:26 PM MDT	Special Weather Statement	TFX	Blaine	49 min
Jun 9, 9:30 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	45 min
Jun 9, 9:37 PM MDT	Special Weather Statement	TFX	Blaine	23 min
Jun 9, 9:38 PM MDT	Special Weather Statement	TFX	Fergus	37 min
Jun 9, 9:38 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	40 min
Jun 9, 9:51 PM MDT	Special Weather Statement	TFX	Blaine	24 min
Jun 9, 10:17 PM MDT	Special Weather Statement	TFX	Blaine	28 min
Jun 9, 10:32 PM MDT	Special Weather Statement	TFX	Fergus	43 min
Jun 9, 10:48 PM MDT	Severe Thunderstorm Warning	TFX	Blaine	42 min
Jun 9, 11:34 PM MDT	Special Weather Statement	TFX	Blaine, Fergus, Hill	116 min
Jun 10, 2:11 AM MDT	Special Weather Statement	TFX	Blaine	34 min
Jun 10, 2:53 PM MDT	Special Weather Statement	TFX	Fergus	37 min
Jun 10, 3:08 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	52 min
Jun 10, 3:53 PM MDT	Special Weather Statement	TFX	Fergus	37 min
Jun 10, 4:22 PM MDT	Special Weather Statement	TFX	Cascade	23 min
Jun 10, 4:56 PM MDT	Special Weather Statement	TFX	Cascade	34 min
Jun 10, 5:33 PM MDT	Special Weather Statement	TFX	Cascade	27 min

Nearby

Severe Thunderstorm Warnings in Montana, 2021 Every severe thunderstorm warning in 2021

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.