Alert archive / Montana / Special Weather Statements in 2021
Special Weather Statement, NWS Missoula, MT
NWS Missoula, MT issued this special weather statement at Aug 2, 2021, 2:21 PM MDT for Deer Lodge County, Powell County, Montana. It was in force for 54 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 2, 2021, 2:21 PM MDT (20:21 UTC)
- Expired
- Aug 2, 2021, 3:15 PM MDT
- In force
- 54 min
- Issued by
- NWS Missoula, MT
- Hail
- 0.00 in
- Wind
- 30
Counties Deer Lodge County, MT, Powell County, MT
The radar
The Missoula radar (KMSX), 114 km from the middle of the area, began a volume at 20:24 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
Great_falls, MT (KTFX), launched 12:00Z, 8.4 hours before the alert went out and 214 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
- 13 J/kg
- Mixed-layer CIN
- -239 J/kg
- Mixed-layer LCL
- 2022 m above ground
- 0-6 km bulk shear
- 12 kt
- 0-1 km storm-relative helicity
- -12 m²/s²
- 0-3 km storm-relative helicity
- 46 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
237
WWUS85 KMSO 022021
SPSMSO
Special Weather Statement
National Weather Service Missoula MT
221 PM MDT Mon Aug 2 2021
MTZ007-043-022115-
Butte/Blackfoot Region MT-Potomac/Seeley Lake Region MT-
221 PM MDT Mon Aug 2 2021
...Strong thunderstorms will impact portions of Deer Lodge,
southeastern Granite, northwestern Silver Bow and southeastern Powell
Counties through 315 PM MDT...
At 220 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from 13 miles northeast of Ovando to 12 miles west
of Garrison to 9 miles north of Wisdom. Movement was east at 20 mph.
HAZARD...Visibility one-half mile or less.
SOURCE...Radar indicated.
IMPACT...Low visibility could result in dangerous driving
conditions.
Locations impacted include...
Deer Lodge, Drummond, Anaconda, Galen, Warm Springs, Gregson Hot
Springs, Garrison, West Valley, Finn, Jens, Brock Creek, Dewey,
Fishtrap, Racetrack, Helmville, Opportunity, Ramsay, Georgetown,
Princeton and New Chicago.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.
These storms 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 4633 11252 4633 11253 4630 11257 4622 11257
4576 11281 4581 11300 4588 11311 4588 11318
4582 11327 4581 11334 4576 11338 4588 11347
4649 11316 4726 11307 4718 11305 4718 11280
4683 11280 4683 11253 4670 11253 4670 11248
TIME...MOT...LOC 2020Z 291DEG 20KT 4717 11300 4648 11308 4574 11345
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...<30 MPH
$$The office that day
Everything else NWS Missoula, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 1, 6:30 PM MDT | Areal Flood Advisory | MSO | Flathead, Lake | 3 hr |
| Aug 1, 6:33 PM MDT | Areal Flood Advisory | MSO | Flathead | 3 hr |
| Aug 1, 6:40 PM MDT | Areal Flood Advisory | MSO | Silver Bow | 10 min |
| Aug 1, 6:46 PM MDT | Special Weather Statement | MSO | Flathead | 29 min |
| Aug 1, 6:49 PM MDT | Flash Flood Warning | MSO | Silver Bow | 97 min |
| Aug 2, 10:09 AM MDT | Flash Flood Watch | MSO | Deer Lodge, Silver Bow | 9 hr |
| Aug 2, 2:18 PM MDT | Special Weather Statement | MSO | Flathead | 42 min |
| Aug 2, 2:54 PM MDT | Special Weather Statement | MSO | Silver Bow | 51 min |
| Aug 2, 3:05 PM MDT | Special Weather Statement | MSO | Flathead | 55 min |
| Aug 2, 5:59 PM MDT | Dense Fog Advisory | MSO | Flathead, Lake, Sanders | 17 hr |
| Aug 1, 6:30 PM MDT | Flash Flood Warning | MSO | Lemhi | 3 hr |
| Aug 1, 7:22 PM MDT | Areal Flood Advisory | MSO | Idaho | 113 min |
| Aug 1, 7:53 PM MDT | Areal Flood Advisory | MSO | Idaho | 112 min |
| Aug 1, 7:59 PM MDT | Areal Flood Warning | MSO | Lemhi | 3 hr |
| Aug 1, 8:15 PM MDT | Areal Flood Advisory | MSO | Idaho | 2 hr |
| Aug 1, 10:01 PM MDT | Areal Flood Advisory | MSO | Idaho | 119 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.