Alert archive / Montana / Red Flag Warnings in 2021

Red Flag Warning 20, NWS Missoula, MT

September 16, 20217 counties in Montana

NWS Missoula, MT issued this red flag warning at Sep 16, 2021, 2:39 PM MDT for 7 counties in Montana. It took effect at Sep 17, 2021, 1:00 PM MDT. It was in force for 32 hr. 37 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Sep 16, 2021, 2:39 PM MDT (20:39 UTC)
In effect from
Sep 17, 2021, 1:00 PM MDT
Expired
Sep 18, 2021, 9:00 PM MDT
In force
32 hr
Issued by
NWS Missoula, MT

Counties Beaverhead County, MT, Deer Lodge County, MT, Granite County, MT, Jefferson County, MT, Madison County, MT, Powell County, MT, Silver Bow County, MT

The radar

The Missoula radar (KMSX), 154 km from the middle of the area, began a volume at 20:36 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

TimeReportWhereRemark
Sep 18, 11:02 AM MDTNON-TSTM WND GST 406 Nnw Lakeview, MTMESONET STATION RRDM8 RED ROCK RAWS.
Sep 18, 11:46 AM MDTNON-TSTM WND GST 403 Sse Butte, MTASOS STATION KBTM BUTTE-MOONEY AP.
Sep 18, 12:11 PM MDTNON-TSTM WND GST 52Macdonald Pass, MTCORRECTS PREVIOUS NON-TSTM WND GST REPORT FROM MTMDP. MACDONALD PASS US-12 MP 27.9, MT. MTMDP (MT DOT) MEASURED 37G52 MPH AT 12:11 AND 12:15 PM MDT.
Sep 18, 12:11 PM MDTNON-TSTM WND GST 52Mtmdp, MTMACDONALD PASS US-12 MP 27.9, MT. MTMDP (MT DOT) ELEV: 6325 FT.; LAT/LON: 46.56148/-112.30931 WINDS OF 37G52 MPH OBSERVED AT 12:11 AND 12:15 PM MDT.
Sep 18, 12:11 PM MDTNON-TSTM WND GST 52Mtmdp, MTMACDONALD PASS US-12 MP 27.9, MT. MTMDP (MT DOT) MEASURED 37G52 MPH AT 12:11 AND 12:15 PM MDT.
Sep 18, 12:15 PM MDTNON-TSTM WND GST 52Macdonald Pass, MTMACDONALD PASS HWY 12 SENSOR.
Sep 18, 12:16 PM MDTNON-TSTM WND GST 461 Ese Wise River, MTMESONET STATION WRSM8 WISE RIVER.
Sep 18, 12:25 PM MDTNON-TSTM WND GST 4118 Wnw West Yellowstone, MTMESONET STATION MTRAY RAYNOLDS PASS (MT DOT).
Sep 18, 12:42 PM MDTNON-TSTM WND GST 475 Ene Dillon, MTASOS STATION KDLN DILLON AIRPORT.
Sep 18, 12:45 PM MDTNON-TSTM WND GST 436 Se Jackson, MTMESONET STATION MTBHP BIG HOLE PASS (MT DOT).
Sep 18, 12:47 PM MDTNON-TSTM WND GST 4510 Wsw Grant, MTMESONET STATION BRRM8 BRENNER RAWS.
Sep 18, 1:16 PM MDTNON-TSTM WND GST 433 Ssw Ennis, MTMESONET STATION ENNM8 ENNIS RAWS.
Sep 18, 1:19 PM MDTNON-TSTM WND GST 429 Ssw Jackson, MTMESONET STATION BDLM8 BEAVERHEAD DEERLODGE NO. 2.
Sep 18, 1:23 PM MDTNON-TSTM WND GST 594 Nne Mcallister, MT59 MPH WIND GUST AT NORRIS HILL MDT.
Sep 18, 1:59 PM MDTNON-TSTM WND GST 424 Ne Lima, MTMESONET STATION LMRM8 ANTELOPE RAWS.
Sep 18, 2:00 PM MDTNON-TSTM WND GST 427 N Dell, MTMESONET STATION MTM16 6.6 N DELL (MT-MESO).
Sep 18, 2:00 PM MDTNON-TSTM WND GST 496 Se Jackson, MTMESONET STATION MTBHP BIG HOLE PASS (MT DOT).
Sep 18, 2:02 PM MDTNON-TSTM WND GST 466 Nnw Lakeview, MTMESONET STATION RRDM8 RED ROCK RAWS.
Sep 18, 2:15 PM MDTNON-TSTM WND GST 448 Ne Bannack, MTMESONET STATION MTM14 8.3 NE BANNACK (MT-MESO).
Sep 18, 2:16 PM MDTNON-TSTM WND GST 513 Ssw Ennis, MTMESONET STATION ENNM8 ENNIS RAWS.
Sep 18, 2:22 PM MDTNON-TSTM WND GST 4011 Sw Basin, MTMESONET STATION MTELK ELK PARK (MT DOT).
Sep 18, 2:43 PM MDTNON-TSTM WND GST 4522 Sw Cameron, MTMESONET STATION BTKM8 BURNT CREEK RAWS.
Sep 18, 2:47 PM MDTNON-TSTM WND GST 5310 Wsw Grant, MTMESONET STATION BRRM8 BRENNER RAWS.
Sep 18, 3:05 PM MDTNON-TSTM WND GST 4921 Sw Lima, MTMESONET STATION HRKM8 HARKNESS RAWS.
Sep 18, 3:10 PM MDTNON-TSTM WND GST 47Monida, MTMESONET STATION MTMQM MONIDA PASS (MT DOT).
Sep 18, 3:18 PM MDTNON-TSTM WND GST 455 Ene Dillon, MTASOS STATION KDLN DILLON AIRPORT.
Sep 18, 3:26 PM MDTNON-TSTM WND GST 4318 Wnw West Yellowstone, MTMESONET STATION MTRAY RAYNOLDS PASS (MT DOT).
Sep 18, 3:43 PM MDTNON-TSTM WND GST 4522 Sw Cameron, MTMESONET STATION BTKM8 BURNT CREEK RAWS.
Sep 18, 3:53 PM MDTNON-TSTM WND GST 513 Nne Newcomb, MT
Sep 18, 4:15 PM MDTNON-TSTM WND GST 401 W Whitehall, MTMESONET STATION WHHM8 WHITEHALL RAWS.
Sep 18, 4:59 PM MDTNON-TSTM WND GST 424 Ne Lima, MTMESONET STATION LMRM8 ANTELOPE RAWS.
Sep 18, 5:05 PM MDTNON-TSTM WND GST 5121 Sw Lima, MTMESONET STATION HRKM8 HARKNESS RAWS.
Sep 18, 5:16 PM MDTNON-TSTM WND GST 481 Ese Wise River, MTMESONET STATION WRSM8 WISE RIVER.
Sep 18, 5:22 PM MDTNON-TSTM WND GST 4311 Sw Basin, MTMESONET STATION MTELK ELK PARK (MT DOT).
Sep 18, 6:00 PM MDTNON-TSTM WND GST 492 Wsw Deer Lodge, MTMESONET STATION K38S 1.8 W DEER LODGE (GTFWFO).
Sep 18, 6:08 PM MDTNON-TSTM WND GST 51Avon North Mt Hwy 141 M, MTOBSERVATION FROM MESOWEST SITE: AVON NORTH MT-141 MP 8.1, MT. MTAVN (MT DOT). ELEV: 5085 FT.; LAT/LON: 46.69679/-112.65944 LOCATION FOR THIS LSR ESTIMATED FROM MESOWEST MAP.
Sep 18, 6:43 PM MDTNON-TSTM WND GST 4622 Sw Cameron, MTMESONET STATION BTKM8 BURNT CREEK RAWS.

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, 8.7 hours before the alert went out and 231 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-pSkew-T log-p diagram, Great_falls, MT at 12:00Z on 2021-09-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Great_falls, MT at 12:00Z on 2021-09-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -125 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1222 m above ground
0-6 km bulk shear
75 kt
0-1 km storm-relative helicity
-125 m²/s²
0-3 km storm-relative helicity
96 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

507 
WWUS85 KMSO 162039
RFWMSO

URGENT - FIRE WEATHER MESSAGE
National Weather Service Missoula MT
239 PM MDT Thu Sep 16 2021

MTZ110-111-180300-
/O.NEW.KMSO.FW.W.0020.210917T1900Z-210919T0300Z/
Deerlodge/West Beaverhead-East Beaverhead-
239 PM MDT Thu Sep 16 2021

...RED FLAG WARNING IN EFFECT FROM 1 PM FRIDAY TO 9 PM MDT
SATURDAY...

* Affected area: Fire Zone 110 (Deerlodge/West Beaverhead). Fire 
  Zone 111 (East Beaverhead). 

* Impacts: The combination of gusty winds and low humidity will
  result in critical fire weather conditions. An exceptional fire
  weather event is taking shape Saturday. Strong and potentially
  damaging winds are expected. Use extra caution with potential 
  ignition sources, especially in grassy areas.

* Winds: Southwest to west winds gusting between 30 to 40 mph on 
  Friday increasing to 50 to 60 mph on Saturday. 

* Minimum humidities: 10 to 15 percent. 

&&

$$
2 follow-up statements
096 
WWUS85 KMSO 180241
RFWMSO

URGENT - FIRE WEATHER MESSAGE
National Weather Service Missoula MT
841 PM MDT Fri Sep 17 2021

MTZ110-111-190300-
/O.CON.KMSO.FW.W.0020.000000T0000Z-210919T0300Z/
Deerlodge/West Beaverhead-East Beaverhead-
841 PM MDT Fri Sep 17 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT SATURDAY...

* Affected area:
   Fire Zone 110 (Deerlodge/West Beaverhead).
   Fire Zone 111 (East Beaverhead).

* Impacts: The combination of gusty winds and low humidity will
  result in critical fire weather conditions. An exceptional fire
  weather event is taking shape Saturday. Expect strong and
  potentially damaging winds. Use extra caution with potential 
  ignition sources, especially in grassy areas. 

* Winds: Southwest to west winds gusting between 50 to 60 mph 

* Minimum humidities: 10 to 15 percent.

&&

$$
219 
WWUS85 KMSO 190235
RFWMSO

URGENT - FIRE WEATHER MESSAGE
National Weather Service Missoula MT
835 PM MDT Sat Sep 18 2021

MTZ110-111-190345-
/O.EXP.KMSO.FW.W.0020.000000T0000Z-210919T0300Z/
Deerlodge/West Beaverhead-East Beaverhead-
835 PM MDT Sat Sep 18 2021

...RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING...

* Affected area: Fire Zone 110 (Deerlodge/West Beaverhead). Fire 
  Zone 111 (East Beaverhead). 


&&

$$

Nearby

Red Flag Warnings in Montana, 2021Every red flag 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.