Alert archive / Montana / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 9, NWS Missoula, MT
NWS Missoula, MT issued this severe thunderstorm warning at Jul 21, 2021, 7:30 PM MDT for Granite County, Missoula County, Powell County, Montana. It was in force for 30 min. 3 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, 7:30 PM MDT (01:30 UTC)
- Expired
- Jul 21, 2021, 8:00 PM MDT
- In force
- 30 min
- Issued by
- NWS Missoula, MT
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Granite County, MT, Missoula County, MT, Powell County, MT
The radar
The Missoula radar (KMSX), 64 km from the middle of the area, began a volume at 01:29 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, 7:40 PM MDT | HAIL 0.7 | Ovando, MT | WIND GUST 30MPH, 0.35 INCH RAIN IN 20 MINUTES. |
| Jul 21, 7:45 PM MDT | HAIL 1.75 | 4 Wnw Ovando, MT | GOLF BALL SIZED HAIL REPORTED AT THE MONTURE CAMPGROUND. LASTED FOR ABOUT 5 MINUTES. |
| Jul 21, 7:45 PM MDT | HAIL 1.75 | 4 Wnw Ovando, MT | GOLF-BALL SIZED HAIL REPORTED AT THE MONTURE CAMPGROUND. LASTED FOR ABOUT 5 MINUTES. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Spokane, WA (KOTX), launched 00:00Z, 1.5 hours before the alert went out and 256 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2525 m above ground
- 0-6 km bulk shear
- 55 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- 79 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
185
WUUS55 KMSO 220130
SVRMSO
MTC039-063-077-220200-
/O.NEW.KMSO.SV.W.0009.210722T0130Z-210722T0200Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Missoula MT
730 PM MDT Wed Jul 21 2021
The National Weather Service in Missoula has issued a
* Severe Thunderstorm Warning for...
Southeastern Missoula County in west central Montana...
Northeastern Granite County in west central Montana...
West central Powell County in west central Montana...
* Until 800 PM MDT.
* At 729 PM MDT, a severe thunderstorm was located near Ovando, or 19
miles north of Drummond, moving northeast at 30 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...
Ovando.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4682 11326 4687 11340 4729 11306 4718 11305
4718 11283
TIME...MOT...LOC 0129Z 218DEG 28KT 4694 11323
HAIL...1.00IN
WIND...60MPH
$$The office that day
Everything else NWS Missoula, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 6:01 PM MDT | Severe Thunderstorm Warning | MSO | Missoula, Powell | 29 min |
| Jul 21, 6:38 PM MDT | Special Weather Statement | MSO | Granite | 22 min |
| Jul 21, 6:54 PM MDT | Severe Thunderstorm Warning | MSO | Granite, Missoula, Powell | 36 min |
| Jul 21, 7:20 PM MDT | Special Weather Statement | MSO | Granite | 25 min |
| Jul 21, 7:51 PM MDT | Special Weather Statement | MSO | Powell | 9 min |
| Jul 21, 8:02 PM MDT | Special Weather Statement | MSO | Powell | 28 min |
| Jul 21, 9:04 PM MDT | Special Weather Statement | MSO | Granite | 41 min |
| Jul 21, 9:18 PM MDT | Severe Thunderstorm Warning | MSO | Granite | 27 min |
| Jul 21, 10:12 PM MDT | Special Weather Statement | MSO | Powell | 48 min |
| Jul 22, 1:32 PM MDT | Red Flag Warning | MSO | Beaverhead, Deer Lodge, Granite, Jefferson, Madison, Powell and 1 more | 31 hr |
| Jul 22, 1:59 PM MDT | Special Weather Statement | MSO | 46 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.