Alert archive / Montana / Red Flag Warnings in 2021

Red Flag Warning 7, NWS Great Falls, MT

July 14, 20219 counties in Montana

NWS Great Falls, MT issued this red flag warning at Jul 14, 2021, 1:32 PM MDT for 9 counties in Montana. It took effect at Jul 15, 2021, 2:00 PM MDT. It was in force for 7 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 14, 2021, 1:32 PM MDT (19:32 UTC)
In effect from
Jul 15, 2021, 2:00 PM MDT
Expired
Jul 15, 2021, 9:00 PM MDT
In force
7 hr
Issued by
NWS Great Falls, MT

Counties Broadwater County, MT, Cascade County, MT, Fergus County, MT, Gallatin County, MT, Jefferson County, MT, Judith Basin County, MT, Lewis and Clark County, MT, Meagher County, MT, Powell County, MT

The radar

The Great Falls radar (KTFX), 86 km from the middle of the area, began a volume at 19:33 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, 7.5 hours before the alert went out and 101 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 2021-07-14Temperature 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 12:00Z on 2021-07-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 6 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
1308 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
6 m²/s²
0-3 km storm-relative helicity
58 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

363 
WWUS85 KTFX 141932
RFWTFX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Great Falls MT
132 PM MDT Wed Jul 14 2021

MTZ116-118-151200-
/O.NEW.KTFX.FW.W.0007.210715T2000Z-210716T0300Z/
Lincoln Ranger District of the Helena National Forest-
Helena and Townsend Ranger Districts of the Helena National Forest-
132 PM MDT Wed Jul 14 2021

...RED FLAG WARNING IN EFFECT FROM 2 PM TO 9 PM MDT THURSDAY FOR
GUSTY WINDS, LOW RELATIVE HUMIDITY, AND INCREASING THUNDERSTORM
ACTIVITY FOR FIRE WEATHER ZONES 116 AND 118...

The National Weather Service in Great Falls has issued a Red Flag
Warning for gusty winds and low relative humidity, which is in
effect from 2 PM to 9 PM MDT Thursday.

* AFFECTED AREA...Lincoln Ranger District of the Helena National 
  Forest and Helena and Townsend Ranger Districts of the Helena 
  National Forest.

* WINDS...West 10 to 20 mph, with gusts up to 30 mph.

* RELATIVE HUMIDITY...As low as 13 percent.

* THUNDERSTORMS...Scattered wet and dry

* IMPACTS...In addition to the threat to create new fire starts due
  to lightning strikes, thunderstorms will be capable of producing
  gusty and erratic outflows, which could lead to extreme fire 
  behavior on existing fires.
  

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.

&&

Moldan

$$

http://www.weather.gov/greatfalls
3 follow-up statements
007 
WWUS85 KTFX 150814
RFWTFX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Great Falls MT
214 AM MDT Thu Jul 15 2021

MTZ117-152200-
/O.EXA.KTFX.FW.W.0007.210715T2000Z-210716T0300Z/
Central and Eastern Lewis and Clark National Forest Areas-
214 AM MDT Thu Jul 15 2021

...RED FLAG WARNING IN EFFECT FROM 2 PM THIS AFTERNOON TO 9 PM MDT
THIS EVENING FOR LOW HUMIDITY AND POTENTIAL DRY THUNDERSTORMS FOR 
FIRE WEATHER ZONE 117...

The National Weather Service in Great Falls has issued a Red Flag
Warning for increasing thunderstorm activity, which is in effect
from 2 PM this afternoon to 9 PM MDT this evening.

* AFFECTED AREA...Central and Eastern Lewis and Clark National 
  Forest Areas.

* WINDS...West 10 to 15 mph, with gusts up to 25 mph.

* RELATIVE HUMIDITY...As low as 14 percent.

* LIGHTNING...Some storms could produce frequent lightning 
  strikes.

* THUNDERSTORMS...Scattered wet and dry.

* OUTFLOW WINDS...Thunderstorm outflow wind gusts of 30 to 50 mph
  are possible.

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.

&&

$$

MTZ116-118-152200-
/O.CON.KTFX.FW.W.0007.210715T2000Z-210716T0300Z/
Lincoln Ranger District of the Helena National Forest-
Helena and Townsend Ranger Districts of the Helena National Forest-
214 AM MDT Thu Jul 15 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 2 PM THIS AFTERNOON TO
9 PM MDT THIS EVENING FOR LOW HUMIDITY AND POTENTIAL DRY
THUNDERSTORMS FOR FIRE WEATHER ZONES 116 AND 118...

* AFFECTED AREA...Lincoln Ranger District of the Helena National 
  Forest and Helena and Townsend Ranger Districts of the Helena 
  National Forest.

* WINDS...West 10 to 15 mph, with gusts up to 25 mph.

* RELATIVE HUMIDITY...As low as 14 percent.

* LIGHTNING...Some storms could produce frequent lightning 
  strikes.

* THUNDERSTORMS...Scattered wet and dry.

* OUTFLOW WINDS...Thunderstorm outflow wind gusts of 30 to 50 mph
  are possible.

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
966 
WWUS85 KTFX 152216
RFWTFX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Great Falls MT
416 PM MDT Thu Jul 15 2021

MTZ116>118-160300-
/O.CON.KTFX.FW.W.0007.000000T0000Z-210716T0300Z/
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-
416 PM MDT Thu Jul 15 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT THIS EVENING
FOR LOW HUMIDITY AND POTENTIAL DRY THUNDERSTORMS FOR FIRE WEATHER
ZONE 117...

* AFFECTED AREA...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.

* WINDS...West 10 to 15 mph with gusts up to 25 mph.

* RELATIVE HUMIDITY...As low as 14 percent.

* LIGHTNING...Some storms could produce frequent lightning 
  strikes.

* THUNDERSTORMS...Scattered wet and dry.

* OUTFLOW WINDS...Thunderstorm outflow wind gusts of 30 to 50 mph 
  are possible.

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
327 
WWUS85 KTFX 160241
RFWTFX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Great Falls MT
841 PM MDT Thu Jul 15 2021

MTZ116>118-160345-
/O.EXP.KTFX.FW.W.0007.000000T0000Z-210716T0300Z/
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-
841 PM MDT Thu Jul 15 2021

...RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING FOR LOW
HUMIDITY AND POTENTIAL DRY THUNDERSTORMS FOR FIRE WEATHER ZONES 
116, 117, AND 118...

Relative humidity percentages have climbed back up above 20 percent
and only an isolated thunderstorm or two will persist into the late
evening hours. As such, the Red Flag Warning will be allowed to
expire as scheduled at 9 PM MDT.

$$

http://www.weather.gov/greatfalls

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 14, 1:38 PM MDTExcessive Heat WatchTFX49 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.