Alert archive / Montana / Red Flag Warnings in 2021

Red Flag Warning 6, NWS Great Falls, MT

July 11, 202118 counties in Montana

NWS Great Falls, MT issued this red flag warning at Jul 11, 2021, 12:33 AM MDT for 18 counties in Montana. It took effect at Jul 11, 2021, 12:00 PM MDT. It was in force for 9 hr. 28 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
Jul 11, 2021, 12:33 AM MDT (06:33 UTC)
In effect from
Jul 11, 2021, 12:00 PM MDT
Expired
Jul 11, 2021, 9:00 PM MDT
In force
9 hr
Issued by
NWS Great Falls, MT

Counties Blaine County, MT, Broadwater County, MT, Cascade County, MT, Chouteau County, MT, Fergus County, MT, Gallatin County, MT, Glacier County, MT, Hill County, MT, Jefferson County, MT, Judith Basin County, MT, Lewis and Clark County, MT, Liberty County, MT, Meagher County, MT, Phillips County, MT, Pondera County, MT, Powell County, MT, Teton County, MT, Toole County, MT

The radar

The Great Falls radar (KTFX), 24 km from the middle of the area, began a volume at 06:34 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
Jul 11, 3:23 PM MDTTSTM WND GST 603 Sw Cut Bank, MTASOS STATION KCTB CUT BANK AIRPORT. SUSTAINED WIND 41MPH AT TIME OF GUST.
Jul 11, 3:24 PM MDTTSTM WND DMGCut Bank, MTPOWER LINES DOWN IN CUT BANK WITH A HIGH NUMBER OF POWER OUTAGES. ALSO REPORTED A TREE WAS DOWNED.
Jul 11, 3:29 PM MDTTSTM WND GST 633 Sw Cut Bank, MTASOS STATION KCTB CUT BANK AIRPORT.
Jul 11, 3:36 PM MDTTSTM WND GST 566 Nnw Sunburst, MTMESONET STATION MTSWT SWEETGRASS (MT DOT).
Jul 11, 4:00 PM MDTTSTM WND GST 60Toole County Airport, MTMEASURED AT TOOLE COUNTY AIRPORT, VIA AMBIENT WEATHER.
Jul 11, 4:16 PM MDTTSTM WND GST 53Galata, MTMESONET STATION DW9605 GALATA.
Jul 11, 4:30 PM MDTTSTM WND DMG8 Ese Lothair, MTSWING SET BLOWN AWAY, MANY TREES HAD SIGNIFICANT NUMBER OF LIMBS BLOWN OFF.
Jul 11, 4:34 PM MDTTSTM WND GST 6410 Nne Galata, MT
Jul 11, 4:50 PM MDTTSTM WND GST 55Inverness, MTPEAK GUST OVER LAST 30 MIN AS MEASURED BY MTINV.
Jul 11, 4:58 PM MDTTSTM WND GST 5813 S Inverness, MTVIA AMBIENT WEATHER MESONET.
Jul 11, 4:59 PM MDTTSTM WND GST 5810 N Joplin, MT
Jul 11, 5:00 PM MDTTSTM WND GST 6511 S Rudyard, MTVIA AMBIENT WEATHER MESONET.
Jul 11, 5:05 PM MDTTSTM WND GST 622 E Inverness, MT
Jul 11, 5:14 PM MDTTSTM WND GST 7713 W Big Sandy, MTVIA AMBIENT WEATHER MESONET.
Jul 11, 5:20 PM MDTTSTM WND GST 611 N Loma, MT
Jul 11, 5:24 PM MDTTSTM WND DMGVerona, MTPOWERLINES DOWN ON US 87 NEAR VERONA.
Jul 11, 5:30 PM MDTTSTM WND DMG1 Sw Big Sandy, MTSEMI BLOWN OF HIGHWAY 87, NEAR MILE MARKER 78. POWER LINES BLOWN DOWN IN THE AREA. UNKNOWN NUMBER OF INJURIES. REPORT VIA MT HIGHWAY PATROL. TIME OF EVENT IS ESTIMATED.
Jul 11, 5:30 PM MDTTSTM WND GST 551 Ne Fort Benton, MTAWOS STATION 79S9 FORT BENTON APT.
Jul 11, 5:31 PM MDTNON-TSTM WND GST 6314 Sw Simms, MTMILITARY SITE MEASURED NON CONVECTIVE GUST OF 63 MPH WITH SOUTHWARD MOVING SYNOPTIC BOUNDARY.
Jul 11, 5:41 PM MDTTSTM WND GST 66Havre County Airport, MTMEASURED AT KHVR.
Jul 11, 5:45 PM MDTTSTM WND GST 5918 E Fort Benton, MT
Jul 11, 6:00 PM MDTTSTM WND GST 627 Wsw Havre, MTMEASURED BY SITE MTM06.
Jul 11, 6:01 PM MDTTSTM WND GST 555 Ssw Hays, MT
Jul 11, 6:23 PM MDTTSTM WND GST 661 Wnw Great Falls, MTDELAYED REPORT.
Jul 11, 6:52 PM MDTTSTM WND GST 547 Ese Hilger, MTMESONET STATION JPKM8 JUDITH PEAK RAWS.
Jul 11, 7:15 PM MDTNON-TSTM WND GST 562 Wnw Malta, MTAWOS STATION KM75 MALTA.
Jul 11, 7:18 PM MDTTSTM WND GST 5713 S Fort Belknap, MTMESONET STATION FBLM8 FORT BELKNAP RAWS.
Jul 11, 7:20 PM MDTNON-TSTM WND GST 551 Ese Zortman, MTTIME ESTIMATED FROM RADAR. MESONET STATION ALDM8 ZORTMAN 1E.

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 00:00Z, 6.6 hours before the alert went out and 37 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 00:00Z on 2021-07-11Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Great_falls, MT at 00:00Z on 2021-07-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 2 square meters per square second.193958Sfc1 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
4077 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
2 m²/s²
0-3 km storm-relative helicity
52 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

610 
WWUS85 KTFX 110633
RFWTFX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Great Falls MT
1233 AM MDT Sun Jul 11 2021

MTZ112>118-112200-
/O.NEW.KTFX.FW.W.0006.210711T1800Z-210712T0300Z/
Eastern Glacier/Toole/Central/Eastern Pondera/Liberty-
Hill and Blaine Counties-
Lewis and Clark National Forest Rocky Mountain District-
Rocky Mountain Front-Chouteau and Fergus Counties-
Lincoln Ranger District of the Helena National Forest-
Central and Eastern Lewis and Clark National Forest Areas-
Helena and Townsend Ranger Districts of the Helena National Forest-
1233 AM MDT Sun Jul 11 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS
EVENING FOR HOT TEMPERATURES, GUSTY WINDS, LOW RELATIVE HUMIDITY
AND A WIND SHIFT FOR FIRE WEATHER ZONES 112, 113, 114, 115, 116, 
117, AND 118...

The National Weather Service in Great Falls has issued a Red Flag
Warning for hot temperatures, gusty winds, low relative humidity
and a wind shift which is in effect from Noon today to 9 PM MDT 
this evening.

* AFFECTED AREA...Eastern Glacier/Toole/Central/Eastern 
  Pondera/Liberty, Hill and Blaine Counties, Lewis and Clark 
  National Forest Rocky Mountain District-Rocky Mountain Front, 
  Chouteau and Fergus Counties, Lincoln Ranger District of the 
  Helena National Forest, Central and Eastern Lewis and Clark 
  National Forest Areas and Helena and Townsend Ranger Districts 
  of the Helena National Forest.

* TEMPERATURES...90 to 100 degrees.

* WINDS...West 15 to 25 mph with gusts around 35 mph, becoming 
  northwest winds this evening.

* RELATIVE HUMIDITY...As low as 8 percent.

* IMPACTS...The hot temperatures combined with low humidity and
  gust winds could create difficult conditions on any fire today.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions are
either occurring now, or will shortly.  A combination of 
strong winds, low relative humidity, and warm temperatures can
contribute to extreme fire behavior.

Please advise the appropriate officials or fire crews in these
areas of this Red Flag Warning.

&&

$$

http://www.weather.gov/greatfalls
2 follow-up statements
660 
WWUS85 KTFX 111955
RFWTFX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Great Falls MT
155 PM MDT Sun Jul 11 2021

MTZ112>118-120300-
/O.CON.KTFX.FW.W.0006.000000T0000Z-210712T0300Z/
Eastern Glacier/Toole/Central/Eastern Pondera/Liberty-
Hill and Blaine Counties-
Lewis and Clark National Forest Rocky Mountain District-
Rocky Mountain Front-Chouteau and Fergus Counties-
Lincoln Ranger District of the Helena National Forest-
Central and Eastern Lewis and Clark National Forest Areas-
Helena and Townsend Ranger Districts of the Helena National Forest-
155 PM MDT Sun Jul 11 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT THIS EVENING
FOR HOT TEMPERATURES, GUSTY WINDS, AND LOW RELATIVE HUMIDITY AND A
WINDS SHIFT FOR FIRE WEATHER ZONES 112, 113, 114, 115, 116, 117, 
AND 118...

* AFFECTED AREA...Eastern Glacier/Toole/Central/Eastern 
  Pondera/Liberty, Hill and Blaine Counties, Lewis and Clark 
  National Forest Rocky Mountain District-Rocky Mountain Front, 
  Chouteau and Fergus Counties, Lincoln Ranger District of the 
  Helena National Forest, Central and Eastern Lewis and Clark 
  National Forest Areas and Helena and Townsend Ranger Districts 
  of the Helena National Forest.

* TEMPERATURES...In the mid 80s to low 90s.

* WINDS...Northwest 10 to 20 mph with gusts up to 30 mph...shifting
  to the north tonight. A period of gusty north winds is likely
  early this evening across north-central Montana due to a Canadian
  frontal passage and possible thunderstorm outflow. 

* RELATIVE HUMIDITY...As low as 11 percent.

* IMPACTS...The hot temperatures combined with low humidity and
  gust winds could create difficult conditions on any fire today.
  In addition, isolated thunderstorms are possible across areas
  south of the Elkhorns and Big Belts as well as near the Canadian
  border this evening.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions are
either occurring now, or will shortly.  A combination of strong
winds, low relative humidity, and warm temperatures can contribute
to extreme fire behavior.

Please advise the appropriate officials or fire crews in these
areas of this Red Flag Warning.

&&

$$

http://www.weather.gov/greatfalls
884 
WWUS85 KTFX 120302
RFWTFX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Great Falls MT
902 PM MDT Sun Jul 11 2021

MTZ112>118-120415-
/O.EXP.KTFX.FW.W.0006.000000T0000Z-210712T0300Z/
Eastern Glacier/Toole/Central/Eastern Pondera/Liberty-
Hill and Blaine Counties-
Lewis and Clark National Forest Rocky Mountain District-
Rocky Mountain Front-Chouteau and Fergus Counties-
Lincoln Ranger District of the Helena National Forest-
Central and Eastern Lewis and Clark National Forest Areas-
Helena and Townsend Ranger Districts of the Helena National Forest-
902 PM MDT Sun Jul 11 2021

...RED FLAG WARNING HAS EXPIRED FOR FIRE WEATHER ZONES 112, 113, 
114, 115, 116, 117, AND 118...

$$

http://www.weather.gov/greatfalls

The office that day

Everything else NWS Great Falls, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 11, 2:18 PM MDTSpecial Weather StatementTFXGlacier42 min
Jul 11, 2:28 PM MDTSevere Thunderstorm WarningTFXGlacier50 min
Jul 11, 2:58 PM MDTSpecial Weather StatementTFXGlacier32 min
Jul 11, 3:03 PM MDTSevere Thunderstorm WarningTFXGlacier, Toole42 min
Jul 11, 3:40 PM MDTSevere Thunderstorm WarningTFXToole50 min
Jul 11, 4:18 PM MDTSevere Thunderstorm WarningTFXLiberty, Toole27 min
Jul 11, 4:36 PM MDTSpecial Weather StatementTFXPondera24 min
Jul 11, 4:47 PM MDTSpecial Weather StatementTFXChouteau28 min
Jul 11, 5:05 PM MDTSpecial Weather StatementTFXPondera25 min
Jul 11, 5:11 PM MDTSevere Thunderstorm WarningTFXChouteau, Hill49 min
Jul 11, 5:55 PM MDTSevere Thunderstorm WarningTFXBlaine, Chouteau, Hill65 min

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.