Alert archive / Montana / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 10, NWS Great Falls, MT

June 9, 2021Blaine County, Fergus County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jun 9, 2021, 9:09 PM MDT for Blaine County, Fergus County, Montana. It was in force for 21 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 9, 2021, 9:09 PM MDT (03:09 UTC)
Expired: Jun 9, 2021, 9:30 PM MDT
In force: 21 min
Issued by: NWS Great Falls, MT
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Blaine County, MT, Fergus County, MT

The radar

The Glasgow radar (KGGW), 167 km from the middle of the area, began a volume at 03:11 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.

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, 3.2 hours before the alert went out and 142 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.

480 
WUUS55 KTFX 100309
SVRTFX
MTC005-027-100330-
/O.NEW.KTFX.SV.W.0010.210610T0309Z-210610T0330Z/

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

The National Weather Service in Great Falls has issued a

* Severe Thunderstorm Warning for...
  Northern Fergus County in central Montana...
  South central Blaine County in north central Montana...

* Until 930 PM MDT.

* At 908 PM MDT, a severe thunderstorm was located 23 miles west of
  Hays, or 28 miles west of Zortman, moving northeast at 40 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Hays.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4798 10862 4792 10864 4792 10888 4777 10890
      4771 10911 4788 10930 4820 10883 4799 10856
TIME...MOT...LOC 0308Z 230DEG 34KT 4786 10913 

HAIL...1.00IN
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, 9:04 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau, Hill	26 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.