Alert archive / Montana / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 38, NWS Glasgow, MT

June 10, 2021Sheridan County, Montana

NWS Glasgow, MT issued this severe thunderstorm warning at Jun 10, 2021, 4:23 PM MDT for Sheridan County, Montana. It was in force for 67 min. 7 reports 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 10, 2021, 4:23 PM MDT (22:23 UTC)
Expired: Jun 10, 2021, 5:30 PM MDT
In force: 67 min
Issued by: NWS Glasgow, MT
Area: Storm-based polygon
Tornado: Possible
Hail: 1.5 in
Wind: 60.0 mph

County Sheridan County, MT

The radar

The Glasgow radar (KGGW), 177 km from the middle of the area, began a volume at 22:25 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 10, 4:25 PM MDT	HAIL 0.88	6 W Reserve, MT
Jun 10, 4:33 PM MDT	HAIL 1	Antelope, MT	QUARTER SIZE HAIL FELL FOR 20 MINUTES. RECEIVED OVER ONE INCH OF RAIN.
Jun 10, 4:36 PM MDT	TSTM WND GST 60	4 Se Antelope, MT
Jun 10, 4:42 PM MDT	HAIL 1.5	4 Se Antelope, MT	SAME LOCATION AS 60 MPH WIND AT 436 PM
Jun 10, 4:42 PM MDT	HAIL 1.5	4 Se Antelope, MT	SAME LOCATION AS 60 MPH WIND AT 436 PM.
Jun 10, 4:45 PM MDT	TSTM WND DMG	3 Se Coalridge, MT	PIVOT BLOWN OVER. GRAIN BIN BLOWN HALF A MILE INTO A HAY FIELD. ONE OUTBUILDING DESTROYED, ANOTHER LOST A ROOF. FROM SOCIAL MEDIA.
Jun 10, 4:45 PM MDT	HAIL 0.88	1 S Antelope, MT	FROM SOCIAL MEDIA.

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

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 5 storm reports to this severe thunderstorm warning; the first came 10 minutes after it went out.

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 10, 2:30 PM MDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Glasgow Intl Airport, MT (KGGW), launched 12:00Z, 10.4 hours before the alert went out and 174 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: 929 J/kg
Mixed-layer CIN: -480 J/kg
Mixed-layer LCL: 774 m above ground
0-6 km bulk shear: 61 kt
0-1 km storm-relative helicity: 651 m²/s²
0-3 km storm-relative helicity: 663 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

As transmitted.

132 
WUUS55 KGGW 102223
SVRGGW
MTC091-102330-
/O.NEW.KGGW.SV.W.0038.210610T2223Z-210610T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Glasgow MT
423 PM MDT Thu Jun 10 2021

The National Weather Service in Glasgow has issued a

* Severe Thunderstorm Warning for...
  Eastern Sheridan County in northeastern Montana...

* Until 530 PM MDT.

* At 422 PM MDT, a severe thunderstorm was located near Plentywood,
  moving north 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...
  Plentywood, Medicine Lake, Westby, Port Of Raymond, Reserve,
  Raymond, Dagmar, Dooley, Antelope, Comertown and Coalridge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM MDT for northeastern
Montana.

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

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

&&

LAT...LON 4858 10405 4847 10447 4861 10473 4900 10475
      4900 10405
TIME...MOT...LOC 2222Z 197DEG 33KT 4870 10456 

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

NWS Glasgow
rux

2 follow-up statements

723 
WWUS55 KGGW 102259
SVSGGW

Severe Weather Statement
National Weather Service Glasgow MT
459 PM MDT Thu Jun 10 2021

MTC091-102330-
/O.CON.KGGW.SV.W.0038.000000T0000Z-210610T2330Z/
Sheridan MT-
459 PM MDT Thu Jun 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM MDT
FOR NORTHEASTERN SHERIDAN COUNTY...

At 459 PM MDT, a severe thunderstorm was located 7 miles east of Port
Of Raymond, or 18 miles north of Plentywood, moving north 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...
Westby, Port Of Raymond, Comertown, Dagmar, Dooley and Coalridge. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM MDT for northeastern
Montana.

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

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

&&

LAT...LON 4858 10405 4855 10430 4900 10466 4900 10405
TIME...MOT...LOC 2259Z 197DEG 33KT 4902 10441 

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

NWS Glasgow
rux

492 
WWUS55 KGGW 102321
SVSGGW

Severe Weather Statement
National Weather Service Glasgow MT
521 PM MDT Thu Jun 10 2021

MTC091-102330-
/O.EXP.KGGW.SV.W.0038.000000T0000Z-210610T2330Z/
Sheridan MT-
521 PM MDT Thu Jun 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN SHERIDAN COUNTY
WILL EXPIRE AT 530 PM MDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.

A Tornado Watch remains in effect until 900 PM MDT for northeastern
Montana.

LAT...LON 4858 10405 4855 10430 4900 10466 4900 10405
TIME...MOT...LOC 2320Z 197DEG 33KT 4918 10433 

$$

NWS Glasgow
rux

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 Glasgow, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 10, 4:13 PM MDT, 10 minutes earlier.

Area forecast discussion, Jun 10, 4:13 PM MDT, 10 minutes before

Area Forecast Discussion
National Weather Service Glasgow MT
413 PM MDT Thu Jun 10 2021

.DISCUSSION...
Update: This Afternoon and tonight.

There is a Tornado Watch out for our eastern counties and Severe
Thunderstorm Watch out for the rest of the area.

Plenty of lift as an upper level jet and shortwave trough lift
across the area tonight. Moisture, instability and shear
available for rapid thunderstorm development over all of NE MT
this afternoon and into this evening. Most of the activity will
begin to move off to the east in to the Dakotas by around
midnight.

Tornado Threat:
For Sheridan, Daniels, Roosevelt, Richland, and Wibaux there is
enough shear and instability that there is a Tornado Watch in
effect through 900 pm mdt. Possible tornadoes, severe wind gusts,
and large hail 1-3 inches possible.

Severe Thunderstorm Threat:
For Phillips, Petroleum, Garfield, Valley, McCone, Dawson, and
Prairie there is a Severe Thunderstorm Watch in effect until 10 pm
MDT. This area has enough shear, instability, and a slightly drier
atmosphere will produce the main threat for severe wind gusts and
large hail.
Friday, a cooler, post-frontal, drier environment will be in place
with persistent gusty west winds, keeping the need for the current
Lake Wind Advisory in place.

By Friday night, the main active and forcing mechanisms will be
past and calmer conditions will return, allbeit under a building
broad ridge of high pressure from the south.

This will allow for a period of hot and dry weather to prevail
this weekend and into next week.
&&

.AVIATION...

FLIGHT CONDITIONS: Severe Thunderstorm Watch in effect until 1000
pm mdt & Tornado Watch in effect until 900 pm mdt covering all of
NE MT. IFR to LIFR briefly as multiple thunderstorms sweep
through the region during the afternoon and evening hours. All
summertime severe weather threats will be possible. Expect
amendments.

LLWS: Possible due to severe thunderstorms.

WINDS: Winds SE 25-30kts along the MT/ND border through 00z then
shifting to W-SW at 15-20kts through 06z then W-NW 15 to 25 kts through
the remainder of the period as the front sweep across the
remainder of the area overnight.

SYNOPSIS: The weather pattern and ingredients have come together
for severe thunderstorms and possible tornadoes this afternoon
and evening. All summertime severe weather threats are possible,
large hail from 1-3", thunderstorm wind gust possible from from 45-60
kts, and possible tornadoes.
&&

.FIRE WEATHER...
Red Flag Warning through 800 pm MDT this evening due to low
humidities and strong gusty winds for fire weather zones 122 to
include the following counties; McCone; Dawson; Richland Prairie;
and Wibaux counties. A trough of low pressure is forecast to move
across the area creating an environment conducive for severe
thunderstorms. Expect frequent lightning, strong microburst winds,
and hail from these storms. As the trough moves NE across the
area this evening, low RH will wrap NNE across the warning area as
a dryline pushes east through the warned area. A cold front will
move through the area by around midnight tonight bringing cooler
conditions, breezy NW winds and higher RH values.

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...
Lake Wind Advisory until 7 PM MDT Friday For Fort Peck Lake for
Central and Southeast Phillips...Central and Southern Valley...
Garfield...McCone...Petroleum.

Red Flag Warning until 8 PM MDT this evening for MTZ122.

&&

weather.gov/glasgow

In the hours before

Local storm report, Jun 10, 12:34 PM MDT, 3 hours 49 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GLASGOW MT
1234 PM MDT THU JUN 10 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1038 PM     HAIL             6 NNW FOURCHETTE        47.81N 108.04W
06/09/2021  M1.25 INCH       PHILLIPS           MT   PUBLIC

            PHOTO SUBMITTED THROUGH FACEBOOK. LOCATED
            NEAR THE DRY FORK RD AND MIDALE RD.

&&

Local storm report, Jun 10, 1:15 PM MDT, 3 hours 8 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GLASGOW MT
115 PM MDT THU JUN 10 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1000 PM     TSTM WND GST     8 SW ZORTMAN            47.84N 108.65W
06/09/2021  E65 MPH          PHILLIPS           MT   TRAINED SPOTTER

&&

BB

Local storm report, Jun 10, 3:39 PM MDT, 44 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GLASGOW MT
339 PM MDT THU JUN 10 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0337 PM     HAIL             5 N CULBERTSON          48.22N 104.50W
06/10/2021  E1.00 INCH       ROOSEVELT          MT   TRAINED SPOTTER

            AND HEAVY RAIN

&&

BB

Local storm report, Jun 10, 3:55 PM MDT, 28 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GLASGOW MT
355 PM MDT THU JUN 10 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0333 PM     HAIL             18 W SIDNEY             47.71N 104.55W
06/10/2021  M1.50 INCH       RICHLAND           MT   TRAINED SPOTTER

&&

Local storm report, Jun 10, 4:06 PM MDT, 17 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GLASGOW MT
406 PM MDT THU JUN 10 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0400 PM     HAIL             OUTLOOK                 48.89N 104.78W
06/10/2021  E1.00 INCH       SHERIDAN           MT   PUBLIC

            CALL REPORTING NICKEL TO QUARTER SIZE HAIL
            ONGOING.

&&

JEZ

Special weather statement, Jun 10, 4:22 PM MDT, 1 minute before

Special Weather Statement
National Weather Service Glasgow MT
422 PM MDT Thu Jun 10 2021

MTZ016-021-060-102300-
Petroleum MT-Southwest Phillips MT-Central and Southeast Phillips MT-
422 PM MDT Thu Jun 10 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN PHILLIPS AND NORTH
CENTRAL PETROLEUM COUNTIES UNTIL 500 PM MDT...

At 422 PM MDT, Doppler radar was tracking a strong thunderstorm 22
miles northeast of Roy, or 29 miles south of Zortman, moving
northeast at 35 mph.

Nickel size hail and wind gusts up to 50 mph will be possible with
this storm.

Locations impacted include...
Fourchette.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

A Severe Thunderstorm Watch remains in effect until 1000 PM MDT for
northeastern Montana.

LAT...LON 4798 10846 4798 10843 4803 10843 4785 10780
      4740 10831 4758 10831 4759 10833 4757 10833
      4757 10834 4759 10839 4758 10842 4760 10842
      4762 10844 4760 10848 4760 10851 4762 10852
      4761 10858 4762 10863
TIME...MOT...LOC 2222Z 207DEG 31KT 4750 10854

NWS Glasgow
TFJ

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 9, 6:56 PM MDT	Severe Thunderstorm Warning	GGW	Phillips	64 min
Jun 9, 7:51 PM MDT	Severe Thunderstorm Warning	GGW	Phillips	54 min
Jun 9, 8:30 PM MDT	Special Weather Statement	GGW		45 min
Jun 9, 8:33 PM MDT	Special Weather Statement	GGW	Petroleum	42 min
Jun 9, 8:44 PM MDT	Severe Thunderstorm Warning	GGW	Phillips, Valley	61 min
Jun 9, 9:18 PM MDT	Special Weather Statement	GGW		42 min
Jun 9, 9:32 PM MDT	Severe Thunderstorm Warning	GGW	Petroleum, Phillips	58 min
Jun 9, 10:16 PM MDT	Special Weather Statement	GGW	Phillips	44 min
Jun 9, 10:25 PM MDT	Severe Thunderstorm Warning	GGW	Petroleum, Phillips	65 min
Jun 9, 10:37 PM MDT	Special Weather Statement	GGW		38 min
Jun 9, 10:38 PM MDT	Severe Thunderstorm Warning	GGW	Phillips	67 min
Jun 9, 11:28 PM MDT	Severe Thunderstorm Warning	GGW	Phillips, Valley	25 min
Jun 9, 11:56 PM MDT	Special Weather Statement	GGW	Phillips	94 min
Jun 10, 3:47 AM MDT	Red Flag Warning	GGW	Dawson, McCone, Prairie, Richland, Wibaux	16 hr
Jun 10, 2:32 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Richland	16 min
Jun 10, 3:14 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Richland, Roosevelt, Sheridan	61 min
Jun 10, 3:27 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, Petroleum	63 min
Jun 10, 3:31 PM MDT	Severe Thunderstorm Warning	GGW	Daniels, Roosevelt, Sheridan	59 min
Jun 10, 3:41 PM MDT	Tornado Warning	GGW	Richland	34 min
Jun 10, 4:05 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, Petroleum	55 min
Jun 10, 4:12 PM MDT	Tornado Warning	GGW	Richland, Roosevelt	33 min
Jun 10, 4:22 PM MDT	Special Weather Statement	GGW		38 min
Jun 10, 4:38 PM MDT	Severe Thunderstorm Warning	GGW	Richland, Roosevelt, Wibaux	45 min
Jun 10, 5:21 PM MDT	Special Weather Statement	GGW	Garfield	39 min
Jun 10, 5:44 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Richland, Wibaux	61 min
Jun 10, 5:54 PM MDT	Severe Thunderstorm Warning	GGW	Garfield	66 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.