Alert archive / Montana / Special Weather Statements in 2021
Special Weather Statement, NWS Missoula, MT
NWS Missoula, MT issued this special weather statement at Aug 5, 2021, 9:12 PM MDT. It was in force for 48 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
- Aug 5, 2021, 9:12 PM MDT (03:12 UTC)
- Expired
- Aug 5, 2021, 10:00 PM MDT
- In force
- 48 min
- Issued by
- NWS Missoula, MT
- Hail
- 0.50 in
- Wind
- 40
The radar
The Missoula radar (KMSX), 175 km from the middle of the area, began a volume at 03:12 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 nearest sounding before it
Boise Airport, ID (KBOI), launched 00:00Z, 3.2 hours before the alert went out and 252 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
- 484 J/kg
- Mixed-layer CIN
- -147 J/kg
- Mixed-layer LCL
- 3441 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- 72 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.8
The text
As transmitted.
362
WWUS85 KMSO 060312
SPSMSO
Special Weather Statement
National Weather Service Missoula MT
912 PM MDT Thu Aug 5 2021
IDZ009-MTZ006-060400-
Western Lemhi County ID-Bitterroot/Sapphire Mountains MT-
912 PM MDT Thu Aug 5 2021
...A strong thunderstorm will impact portions of northwestern Lemhi
and southwestern Ravalli Counties through 1000 PM MDT...
At 911 PM MDT, Doppler radar was tracking a strong thunderstorm 28
miles west of North Fork, or 37 miles northwest of Salmon, moving
northeast at 40 mph.
HAZARD...Winds in excess of 40 mph and half inch hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is
possible.
This storm will remain over mainly rural areas of northwestern Lemhi,
southeastern Idaho and southwestern Ravalli Counties.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
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.
&&
LAT...LON 4529 11461 4530 11460 4539 11471 4541 11475
4549 11469 4547 11466 4552 11463 4556 11456
4562 11454 4564 11456 4566 11451 4571 11450
4572 11451 4581 11444 4565 11413 4527 11457
TIME...MOT...LOC 0311Z 211DEG 33KT 4543 11458
MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH
$$The office that day
Everything else NWS Missoula, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 5, 6:21 PM MDT | Special Weather Statement | MSO | Powell | 39 min |
| Aug 5, 8:08 PM MDT | Special Weather Statement | MSO | 52 min | |
| Aug 6, 1:13 AM MDT | Special Weather Statement | MSO | Ravalli | 47 min |
| Aug 6, 2:46 PM MDT | Fire Weather Watch | MSO | Beaverhead, Deer Lodge, Granite, Jefferson, Madison, Powell and 1 more | 22 hr |
| Aug 5, 9:20 PM MDT | Special Weather Statement | MSO | Idaho | 40 min |
| Aug 5, 9:24 PM MDT | Special Weather Statement | MSO | Clearwater | 36 min |
| Aug 5, 9:38 PM MDT | Special Weather Statement | MSO | Idaho | 52 min |
| Aug 6, 5:32 PM MDT | Special Weather Statement | MSO | Lemhi | 43 min |
Nearby
Special Weather Statements in Montana, 2021Every special weather statement 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.