Alert archive / Wyoming / Red Flag Warnings in 2021

Red Flag Warning 13, NWS Billings, MT

August 16, 20214 counties in Wyoming; Carter County, Fallon County, Montana

NWS Billings, MT issued this red flag warning at Aug 16, 2021, 1:24 PM MDT for 4 counties in Wyoming; Carter County, Fallon County, Montana. It took effect at Aug 17, 2021, 10:00 AM MDT. It was in force for 14 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: Aug 16, 2021, 1:24 PM MDT (19:24 UTC)
In effect from: Aug 17, 2021, 10:00 AM MDT
Expired: Aug 18, 2021, 12:00 AM MDT
In force: 14 hr
Issued by: NWS Billings, MT

Counties Carter County, MT, Fallon County, MT, Big Horn County, WY, Johnson County, WY, Sheridan County, WY, Washakie County, WY

The radar

The Billings radar (KBLX), 209 km from the middle of the area, began a volume at 19:24 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

Riverton, WY (KRIW), launched 12:00Z, 7.4 hours before the alert went out and 257 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2896 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: -5 m²/s²
0-3 km storm-relative helicity: 3 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

828 
WWUS85 KBYZ 161924
RFWBYZ

URGENT - FIRE WEATHER MESSAGE
National Weather Service Billings MT
124 PM MDT Mon Aug 16 2021

MTZ133-WYZ274-284-171930-
/O.NEW.KBYZ.FW.W.0013.210817T1600Z-210818T0600Z/
Sioux Ranger District Custer National Forest-Sheridan County-
Bighorn National Forest-
124 PM MDT Mon Aug 16 2021

...RED FLAG WARNING IN EFFECT FROM 10 AM TUESDAY TO MIDNIGHT MDT
TUESDAY NIGHT...

The National Weather Service in Billings has issued a Red Flag
Warning...which is in effect from 10 AM Tuesday to midnight MDT
Tuesday night.

* IMPACTS: Low humidities, hot temperatures, gusty winds,
  increasing thunderstorm activity, and a wind shift with a cold
  front, will create erratic fire behavior and possible new fire
  starts.

* AFFECTED AREA: 
   In North Central WY Fire Zones...274...284.
   In Southeast MT and Northwest SD Fire Zone...133.

* COUNTIES AFFECTED: 
   In North Central WY...Big Horn...Johnson...Sheridan...Washakie.
   In Northwest SD...Harding.
   In Southeast MT...Carter...Fallon.

* TEMPERATURES: Highs from 98 to 103.

* HUMIDITY: Minimums from 8 to 13 percent.

* WIND: South 10 to 20 mph with gusts up to 25 mph.

* THUNDERSTORMS: Isolated thunderstorms in the late afternoon and
  evening could produce strong and erratic wind gusts.

* COLD FRONT: Tuesday evening frontal passage will bring a shift to
  northwest winds with gusts of 35 to 45 mph.

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.

&&

$$

MTZ123>132-171930-
/O.EXT.KBYZ.FW.W.0012.000000T0000Z-210818T0600Z/
Gallatin National Forest-Wheatland County/Sweet Grass County-
Stillwater County-Beartooth Ranger District Custer National Forest-
Golden Valley County/Musselshell county-Yellowstone County-
Crow Indian Reservation/Bighorn Canyon Rec Area-
Northern Rosebud/Northern Treasure Counties-
Northern Cheyenne Indian Reservation/Ashland Ranger District
Custer Natl Forest-Custer County-
124 PM MDT Mon Aug 16 2021

...RED FLAG WARNING NOW IN EFFECT UNTIL MIDNIGHT MDT TUESDAY
NIGHT...

* IMPACTS: Low humidities, hot temperatures, gusty winds,
  increasing thunderstorm activity, and a wind shift with a cold
  front, will create erratic fire behavior and possible new fire 
  starts.

* AFFECTED AREA: 
   In South Central MT Fire Zones...123...124...125...126...127
                                    128...129.
   In Southeast MT Fire Zones...130...131...132.

* COUNTIES AFFECTED: 
   In Central MT...Golden Valley...Musselshell...Wheatland.
   In South Central MT...Big Horn...Carbon...Park...Stillwater
                         Sweet Grass...Yellowstone.
   In Southeast MT...Custer...Powder River...Rosebud...Treasure.
   In Southwest MT...Gallatin.

* TEMPERATURES: Highs in the 90s to near 103.

* HUMIDITY: Minimums from 9 to 19 percent. Poor humidity recovery 
  tonight.

* WIND: Southwest 10 to 20 mph with gusts up to 25 mph. Gusts to 
  40 mph on the mountain tops.

* THUNDERSTORMS: Scattered wet and dry thunderstorms are expected
  late this afternoon and evening, and again on Tuesday. Storms 
  may produce strong and erratic wind gusts that extend well away 
  from the storms.

* COLD FRONT: Tuesday afternoon and evening frontal passage will
  bring a shift to northwest winds with gusts of 35 to 45 mph.

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.

&&

$$

http://weather.gov/Billings

3 follow-up statements

772 
WWUS85 KBYZ 170901
RFWBYZ

URGENT - FIRE WEATHER MESSAGE
National Weather Service Billings MT
301 AM MDT Tue Aug 17 2021

MTZ123>132-180600-
/O.CON.KBYZ.FW.W.0012.000000T0000Z-210818T0600Z/
Gallatin National Forest-Wheatland County/Sweet Grass County-
Stillwater County-Beartooth Ranger District Custer National Forest-
Golden Valley County/Musselshell county-Yellowstone County-
Crow Indian Reservation/Bighorn Canyon Rec Area-
Northern Rosebud/Northern Treasure Counties-
Northern Cheyenne Indian Reservation/Ashland Ranger District
Custer Natl Forest-Custer County-
301 AM MDT Tue Aug 17 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT TONIGHT...

* IMPACTS: Low humidities, hot temperatures, gusty winds, wind
  shift with a cold front, and increasing thunderstorm activity
  will create erratic fire behavior. 

* AFFECTED AREA: 
   In South Central MT Fire Zones...123...124...125...126...127
                                    128...129.
   In Southeast MT Fire Zones...130...131...132.

* COUNTIES AFFECTED: 
   In Central MT...Golden Valley...Musselshell...Wheatland.
   In South Central MT...Big Horn...Carbon...Park...Stillwater
                         Sweet Grass...Yellowstone.
   In Southeast MT...Custer...Powder River...Rosebud...Treasure.
   In Southwest MT...Gallatin.

* TEMPERATURES: Highs 94 to 102.

* HUMIDITY: From 9 to 19 percent.

* WIND: South to southwest 10 to 20 mph with gusts to 30 mph.

* THUNDERSTORMS: Scattered wet and dry thunderstorms are expected
  late this afternoon and evening. Storms may produce strong and 
  erratic wind gusts that extend well away from the storms.

* COLD FRONT: Late this afternoon and evening frontal passage will
  bring a shift to northwest winds with gusts of 30 to 45 mph.

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.

&&

$$

MTZ133-WYZ274-284-180600-
/O.CON.KBYZ.FW.W.0013.210817T1600Z-210818T0600Z/
Sioux Ranger District Custer National Forest-Sheridan County-
Bighorn National Forest-
301 AM MDT Tue Aug 17 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 10 AM THIS MORNING TO
MIDNIGHT MDT TONIGHT...

* IMPACTS: Low humidities, hot temperatures, gusty winds, wind
  shift with a cold front, and increasing thunderstorm activity
  will create erratic fire behavior. 

* AFFECTED AREA: 
   In North Central WY Fire Zones...274...284.
   In Southeast MT and Northwest SD Fire Zone...133.

* COUNTIES AFFECTED: 
   In North Central WY...Big Horn...Johnson...Sheridan...Washakie.
   In Northwest SD...Harding.
   In Southeast MT...Carter...Fallon.

* TEMPERATURES: Highs 96 to 104.

* HUMIDITY: From 8 to 14 percent.

* WIND: South 10 to 20 mph with gusts to 30 mph.

* THUNDERSTORMS: Isolated thunderstorms in the late afternoon and 
  evening could produce strong and erratic wind gusts.

* COLD FRONT: This evening frontal passage will bring a shift to
  northwest winds with gusts of 30 to 45 mph.

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.

&&

$$


http://weather.gov/Billings

493 
WWUS85 KBYZ 171959
RFWBYZ

URGENT - FIRE WEATHER MESSAGE
National Weather Service Billings MT
159 PM MDT Tue Aug 17 2021

MTZ123>132-180600-
/O.CON.KBYZ.FW.W.0012.000000T0000Z-210818T0600Z/
Gallatin National Forest-Wheatland County/Sweet Grass County-
Stillwater County-Beartooth Ranger District Custer National Forest-
Golden Valley County/Musselshell county-Yellowstone County-
Crow Indian Reservation/Bighorn Canyon Rec Area-
Northern Rosebud/Northern Treasure Counties-
Northern Cheyenne Indian Reservation/Ashland Ranger District
Custer Natl Forest-Custer County-
159 PM MDT Tue Aug 17 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT TONIGHT...

* IMPACTS: Low humidities, hot temperatures, gusty winds, wind
  shift with a cold front, and increasing thunderstorm activity
  will create erratic fire behavior.

* AFFECTED AREA: 
   In South Central MT Fire Zones...123...124...125...126...127
                                    128...129.
   In Southeast MT Fire Zones...130...131...132.

* COUNTIES AFFECTED: 
   In Central MT...Golden Valley...Musselshell...Wheatland.
   In South Central MT...Big Horn...Carbon...Park...Stillwater
                         Sweet Grass...Yellowstone.
   In Southeast MT...Custer...Powder River...Rosebud...Treasure.
   In Southwest MT...Gallatin.

* TEMPERATURES: Highs 94 to 102.

* HUMIDITY: From 9 to 19 percent.

* WIND: South to southwest 10 to 20 mph with gusts to 30 mph.

* THUNDERSTORMS: Scattered wet and dry thunderstorms are expected 
  late this afternoon and evening. Storms may produce strong and 
  erratic wind gusts that extend well away from the storms.

* COLD FRONT: Late this afternoon and evening frontal passage 
  will bring a shift to northwest winds with gusts of 30 to 45 
  mph.

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.

&&

$$

MTZ133-WYZ274-284-180600-
/O.CON.KBYZ.FW.W.0013.000000T0000Z-210818T0600Z/
Sioux Ranger District Custer National Forest-Sheridan County-
Bighorn National Forest-
159 PM MDT Tue Aug 17 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT TONIGHT...

* IMPACTS: Low humidities, hot temperatures, gusty winds, wind
  shift with a cold front, and increasing thunderstorm activity
  will create erratic fire behavior.

* AFFECTED AREA: 
   In North Central WY Fire Zones...274...284.
   In Southeast MT and Northwest SD Fire Zone...133.

* COUNTIES AFFECTED: 
   In North Central WY...Big Horn...Johnson...Sheridan...Washakie.
   In Northwest SD...Harding.
   In Southeast MT...Carter...Fallon.

* TEMPERATURES: Highs 96 to 104.

* HUMIDITY: From 8 to 14 percent.

* WIND: South 15 to 25 mph with gusts up to 35 mph.

* THUNDERSTORMS: Isolated thunderstorms in the late afternoon and 
  evening could produce strong and erratic wind gusts.

* COLD FRONT: This evening frontal passage will bring a shift to 
  northwest winds with gusts of 30 to 45 mph.

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.

&&

$$


http://weather.gov/Billings

953 
WWUS85 KBYZ 180602
RFWBYZ

URGENT - FIRE WEATHER MESSAGE
National Weather Service Billings MT
1202 AM MDT Wed Aug 18 2021

MTZ133-WYZ274-284-180715-
/O.EXP.KBYZ.FW.W.0013.000000T0000Z-210818T0600Z/
Sioux Ranger District Custer National Forest-Sheridan County-
Bighorn National Forest-
1202 AM MDT Wed Aug 18 2021

...RED FLAG WARNING HAS EXPIRED...

Temperatures have cooled and humidities have risen above 30 
percent. Winds will continue to decrease through the night.

$$

MTZ123>132-180715-
/O.EXP.KBYZ.FW.W.0012.000000T0000Z-210818T0600Z/
Gallatin National Forest-Wheatland County/Sweet Grass County-
Stillwater County-Beartooth Ranger District Custer National Forest-
Golden Valley County/Musselshell county-Yellowstone County-
Crow Indian Reservation/Bighorn Canyon Rec Area-
Northern Rosebud/Northern Treasure Counties-
Northern Cheyenne Indian Reservation/Ashland Ranger District
Custer Natl Forest-Custer County-
1202 AM MDT Wed Aug 18 2021

...RED FLAG WARNING HAS EXPIRED...

Temperatures have cooled and humidities have risen above 30 
percent. Winds will continue to decrease through the night.

$$

http://weather.gov/Billings

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 16, 4:34 PM MDT	Special Weather Statement	BYZ	Yellowstone	41 min
Aug 16, 4:56 PM MDT	Severe Thunderstorm Warning	BYZ	Yellowstone	50 min
Aug 16, 5:45 PM MDT	Special Weather Statement	BYZ	Yellowstone	45 min

Nearby

Red Flag Warnings in Wyoming, 2021 Red Flag Warnings in Montana, 2021 Every 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.