Alert archive / Montana / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 49, NWS Great Falls, MT
NWS Great Falls, MT issued this severe thunderstorm warning at Jul 21, 2021, 5:29 PM MDT for Liberty County, Toole County, Montana. It was in force for 46 min. 2 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
- Jul 21, 2021, 5:29 PM MDT (23:29 UTC)
- Expired
- Jul 21, 2021, 6:15 PM MDT
- In force
- 46 min
- Issued by
- NWS Great Falls, MT
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Liberty County, MT, Toole County, MT
The radar
The Great Falls radar (KTFX), 119 km from the middle of the area, began a volume at 23:31 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 |
|---|---|---|---|
| Jul 21, 5:30 PM MDT | TSTM WND GST 48 | 3 E Lothair, MT | MESONET STATION EW8201 LOTHAIR 3E. |
| Jul 21, 6:04 PM MDT | TSTM WND GST 40 | 3 Nnw Joplin, MT | MESONET STATION EW9056 JOPLIN. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Great_falls, MT (KTFX), launched 12:00Z, 11.5 hours before the alert went out and 118 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.
- Mixed-layer CAPE
- 158 J/kg
- Mixed-layer CIN
- -180 J/kg
- Mixed-layer LCL
- 1952 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 27 m²/s²
- 0-3 km storm-relative helicity
- 33 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
875
WUUS55 KTFX 212329
SVRTFX
MTC051-101-220015-
/O.NEW.KTFX.SV.W.0049.210721T2329Z-210722T0015Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Great Falls MT
529 PM MDT Wed Jul 21 2021
The National Weather Service in Great Falls has issued a
* Severe Thunderstorm Warning for...
Southern Liberty County in north central Montana...
East central Toole County in north central Montana...
* Until 615 PM MDT.
* At 528 PM MDT, a severe thunderstorm was located near Lothair, or
13 miles southwest of Chester, moving east at 25 mph.
HAZARD...60 mph wind gusts and quarter size hail. Severe wind
gusts may occur well away from the heaviest part of the
storm.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage
to roofs, siding, and trees.
* Locations impacted include...
Chester, Joplin, Lothair, Tiber Dam and Galata.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.
&&
LAT...LON 4857 11075 4828 11075 4831 11137 4858 11140
4864 11080
TIME...MOT...LOC 2328Z 248DEG 21KT 4839 11121
HAIL...1.00IN
WIND...60MPH
$$
HART3 follow-up statements
252
WWUS55 KTFX 212344
SVSTFX
Severe Weather Statement
National Weather Service Great Falls MT
544 PM MDT Wed Jul 21 2021
MTC101-212354-
/O.CAN.KTFX.SV.W.0049.000000T0000Z-210722T0015Z/
Toole MT-
544 PM MDT Wed Jul 21 2021
...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL TOOLE COUNTY IS
CANCELLED...
The severe thunderstorm which prompted the warning has moved out of
the warned area. Therefore, the warning has been cancelled.
LAT...LON 4857 11075 4828 11075 4831 11128 4859 11128
4864 11080
TIME...MOT...LOC 2344Z 255DEG 22KT 4841 11105
$$
MTC051-220015-
/O.CON.KTFX.SV.W.0049.000000T0000Z-210722T0015Z/
Liberty MT-
544 PM MDT Wed Jul 21 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM MDT
FOR SOUTHERN LIBERTY COUNTY...
At 544 PM MDT, a severe thunderstorm was located 8 miles southwest of
Chester, moving east at 25 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...
Chester, Joplin, Lothair and Tiber Dam.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.
&&
LAT...LON 4857 11075 4828 11075 4831 11128 4859 11128
4864 11080
TIME...MOT...LOC 2344Z 255DEG 22KT 4841 11105
HAIL...1.00IN
WIND...60MPH
$$
HART148
WWUS55 KTFX 220004
SVSTFX
Severe Weather Statement
National Weather Service Great Falls MT
604 PM MDT Wed Jul 21 2021
MTC051-220015-
/O.CON.KTFX.SV.W.0049.000000T0000Z-210722T0015Z/
Liberty MT-
604 PM MDT Wed Jul 21 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM MDT
FOR EAST CENTRAL LIBERTY COUNTY...
At 603 PM MDT, a severe thunderstorm was located near Joplin, or near
Chester, moving northeast at 30 mph.
HAZARD...60 mph wind gusts and penny size hail.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
Locations impacted include...
Chester and Joplin.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4857 11075 4838 11075 4844 11111 4861 11107
4864 11080
TIME...MOT...LOC 0003Z 239DEG 28KT 4853 11087
HAIL...0.75IN
WIND...60MPH
$$
HART586
WWUS55 KTFX 220009
SVSTFX
Severe Weather Statement
National Weather Service Great Falls MT
609 PM MDT Wed Jul 21 2021
MTC051-220019-
/O.EXP.KTFX.SV.W.0049.000000T0000Z-210722T0015Z/
Liberty MT-
609 PM MDT Wed Jul 21 2021
...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL LIBERTY COUNTY
WILL EXPIRE AT 615 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. However gusty
winds up to 55 mph and heavy rain are still possible with this
thunderstorm.
LAT...LON 4857 11075 4838 11075 4844 11111 4861 11107
4864 11080
TIME...MOT...LOC 0009Z 248DEG 21KT 4854 11084
$$
HARTThe office that day
Everything else NWS Great Falls, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 6:10 PM MDT | Special Weather Statement | TFX | Teton | 35 min |
| Jul 20, 6:14 PM MDT | Special Weather Statement | TFX | Toole | 31 min |
| Jul 20, 6:18 PM MDT | Special Weather Statement | TFX | Cascade | 27 min |
| Jul 20, 6:34 PM MDT | Special Weather Statement | TFX | Teton | 26 min |
| Jul 20, 6:48 PM MDT | Severe Thunderstorm Warning | TFX | Pondera, Teton | 27 min |
| Jul 20, 7:01 PM MDT | Special Weather Statement | TFX | Cascade | 29 min |
| Jul 20, 7:17 PM MDT | Special Weather Statement | TFX | Teton | 28 min |
| Jul 20, 7:47 PM MDT | Special Weather Statement | TFX | 28 min | |
| Jul 20, 7:52 PM MDT | Special Weather Statement | TFX | Cascade | 23 min |
| Jul 20, 8:45 PM MDT | Special Weather Statement | TFX | Chouteau, Judith Basin | 30 min |
| Jul 21, 1:26 PM MDT | Fire Weather Watch | TFX | Broadwater, Cascade, Chouteau, Fergus, Gallatin, Jefferson and 4 more | 25 hr |
| Jul 21, 1:26 PM MDT | Red Flag Warning | TFX | Blaine, Broadwater, Cascade, Chouteau, Fergus, Gallatin and 12 more | 56 hr |
| Jul 21, 2:38 PM MDT | Special Weather Statement | TFX | Glacier | 37 min |
| Jul 21, 2:48 PM MDT | Special Weather Statement | TFX | Pondera | 27 min |
| Jul 21, 2:56 PM MDT | Severe Thunderstorm Warning | TFX | Glacier | 34 min |
| Jul 21, 3:16 PM MDT | Severe Thunderstorm Warning | TFX | Glacier | 29 min |
| Jul 21, 3:23 PM MDT | Special Weather Statement | TFX | Pondera | 37 min |
| Jul 21, 3:49 PM MDT | Special Weather Statement | TFX | Pondera | 26 min |
| Jul 21, 3:50 PM MDT | Severe Thunderstorm Warning | TFX | Pondera | 40 min |
| Jul 21, 3:51 PM MDT | Special Weather Statement | TFX | Teton | 24 min |
| Jul 21, 4:07 PM MDT | Special Weather Statement | TFX | Fergus | 23 min |
| Jul 21, 4:07 PM MDT | Severe Thunderstorm Warning | TFX | Pondera, Teton | 38 min |
| Jul 21, 4:24 PM MDT | Special Weather Statement | TFX | Jefferson | 36 min |
| Jul 21, 4:29 PM MDT | Special Weather Statement | TFX | Madison | 31 min |
| Jul 21, 4:34 PM MDT | Special Weather Statement | TFX | Silver Bow | 26 min |
| Jul 21, 4:39 PM MDT | Special Weather Statement | TFX | Fergus | 36 min |
| Jul 21, 4:42 PM MDT | Special Weather Statement | TFX | Lewis and Clark | 33 min |
| Jul 21, 4:45 PM MDT | Severe Thunderstorm Warning | TFX | Liberty, Pondera, Teton, Toole | 45 min |
| Jul 21, 4:53 PM MDT | Special Weather Statement | TFX | Teton | 22 min |
| Jul 21, 4:54 PM MDT | Special Weather Statement | TFX | Lewis and Clark | 36 min |
| Jul 21, 4:56 PM MDT | Special Weather Statement | TFX | Jefferson | 34 min |
| Jul 21, 4:58 PM MDT | Special Weather Statement | TFX | Broadwater, Jefferson | 32 min |
| Jul 21, 5:02 PM MDT | Special Weather Statement | TFX | Glacier | 28 min |
| Jul 21, 5:04 PM MDT | Special Weather Statement | TFX | Deer Lodge | 26 min |
| Jul 21, 5:21 PM MDT | Special Weather Statement | TFX | Lewis and Clark | 24 min |
| Jul 21, 5:32 PM MDT | Special Weather Statement | TFX | Cascade | 43 min |
Nearby
Severe Thunderstorm Warnings in Montana, 2021Every 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.