Alert archive / California / Red Flag Warnings in 2021

Red Flag Warning 18, NWS Reno, NV

September 26, 20219 counties in California; 7 counties in Nevada

NWS Reno, NV issued this red flag warning at Sep 26, 2021, 9:28 AM PDT for 9 counties in California; 7 counties in Nevada. It took effect at Sep 27, 2021, 12:00 AM PDT. It was in force for 28 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
Sep 26, 2021, 9:28 AM PDT (16:28 UTC)
In effect from
Sep 27, 2021, 12:00 AM PDT
Expired
Sep 28, 2021, 3:54 AM PDT
In force
28 hr
Issued by
NWS Reno, NV

Counties El Dorado County, CA, Lassen County, CA, Madera County, CA, Modoc County, CA, Mono County, CA, Nevada County, CA, Placer County, CA, Plumas County, CA, Sierra County, CA, Churchill County, NV, Douglas County, NV, Lyon County, NV, Mineral County, NV, Pershing County, NV, Storey County, NV, Washoe County, NV

The radar

The Reno radar (KRGX), 46 km from the middle of the area, began a volume at 16:27 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

Reno, NV (KREV), launched 12:00Z, 4.5 hours before the alert went out and 137 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, Reno, NV at 12:00Z on 2021-09-26Temperature 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, Reno, NV at 12:00Z on 2021-09-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 square meters per square second.1939Sfc1 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
2938 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
73 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

399 
WWUS85 KREV 261628
RFWREV

URGENT - FIRE WEATHER MESSAGE
National Weather Service Reno NV
928 AM PDT Sun Sep 26 2021

CAZ272-272300-
/O.UPG.KREV.FW.A.0018.210927T1900Z-210928T0500Z/
/O.NEW.KREV.FW.W.0018.210927T0700Z-210928T1200Z/
Greater Lake Tahoe and Truckee Area-
928 AM PDT Sun Sep 26 2021

...RED FLAG WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 5 AM PDT
TUESDAY FOR GUSTY WINDS AND LOW HUMIDITY FOR THE GREATER LAKE
TAHOE TRUCKEE AREA...

The National Weather Service in Reno has issued a Red Flag
Warning for gusty winds and low humidity, which is in effect from
midnight tonight to 5 AM PDT Tuesday. The Fire Weather Watch is
no longer in effect.

* Changes...Upgraded the Fire Weather Watch. Extended timing.

* Affected Area...Fire Zone 272 Greater Lake Tahoe and Truckee 
  Area.

* Winds...Southwest to West 15 to 25 mph with gusts up to 40 mph.
  Wind prone areas could see gusts up to 50 mph Monday night.

* Humidity...10-20%...RH will increase Monday night to near 40%.

* Duration...3 to 7 hours of critical conditions Monday 
  afternoon. Gusty winds will last for over 24 hours.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

NVZ420-421-272300-
/O.UPG.KREV.FW.A.0018.210927T1900Z-210928T0500Z/
/O.NEW.KREV.FW.W.0018.210927T1800Z-210928T1200Z/
Northern Sierra Front including Carson City, Douglas, Storey,
Southern Washoe, Western Lyon, and Far Southern Lassen Counties-
Southern Sierra Front including Alpine, Northern Mono, Southern
Lyon, and Western Mineral Counties-
928 AM PDT Sun Sep 26 2021

...RED FLAG WARNING IN EFFECT FROM 11 AM MONDAY TO 5 AM PDT
TUESDAY FOR GUSTY WINDS AND LOW HUMIDITY FOR THE SIERRA FRONT...

The National Weather Service in Reno has issued a Red Flag
Warning for gusty winds and low humidity, which is in effect from
11 AM Monday to 5 AM PDT Tuesday. The Fire Weather Watch is no
longer in effect.

* Changes...Upgraded the Fire Weather Watch. Extended timing.

* Affected Area...Fire Zone 420 Northern Sierra Front including 
  Carson City, Douglas, Storey, Southern Washoe, Western Lyon, 
  and Far Southern Lassen Counties, Fire Zone 421 Southern 
  Sierra Front including Alpine, Northern Mono, Southern Lyon 
  and and Western Mineral Counties.

* Winds...Southwest to West 15 to 25 mph with gusts up to 40 mph. 
  Wind prone areas could see gusts up to 50 mph Monday night.

* Humidity...10-15% along and east of US-395. 15-20% west of US- 
  395. RH will increase Monday night to near 40%.

* Duration...3 to 7 hours of critical conditions Monday 
  afternoon. Gusty winds will last for over 18 hours.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

CAZ270-271-278-NVZ423-429-458-272300-
/O.UPG.KREV.FW.A.0018.210927T1900Z-210928T0500Z/
/O.NEW.KREV.FW.W.0018.210927T1800Z-210928T0600Z/
Surprise Valley California-
Western Lassen, Eastern Plumas, and Eastern Sierra Counties-
Eastern Lassen County-West Humboldt Basin in Pershing County-
Lahontan Basin including Churchill and Eastern Mineral Counties-
Northern Washoe County-
928 AM PDT Sun Sep 26 2021

...RED FLAG WARNING IN EFFECT FROM 11 AM TO 11 PM PDT MONDAY FOR
GUSTY WINDS AND LOW HUMIDITY FOR NORTHEAST CALIFORNIA AND WESTERN
NEVADA...

The National Weather Service in Reno has issued a Red Flag
Warning for gusty winds and low humidity, which is in effect from
11 AM to 11 PM PDT Monday. The Fire Weather Watch is no longer in
effect.

* Changes...Upgraded the Fire Weather Watch.

* Affected Area...Fire Zone 270 Surprise Valley California, Fire 
  Zone 271 Western Lassen, Eastern Plumas, and Eastern Sierra 
  Counties, Fire Zone 278 Eastern Lassen County, Fire Zone 423 
  West Humboldt Basin in Pershing County, Fire Zone 429 Lahontan 
  Basin including Churchill and Eastern Mineral Counties and 
  Fire Zone 458 Northern Washoe County.

* Winds...Southwest to West 15 to 25 mph with gusts up to 40 mph.
  Wind prone areas could see gusts up to 50 mph Monday evening.

* Humidity...10-15% along and east of US-395. 15-20% west of US-
  395. RH will increase Monday evening to near 50%.

* Duration...3 to 7 hours of critical conditions Monday afternoon.
  Gusty winds will last for over 12 hours.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

CAZ274-272300-
/O.EXT.KREV.FW.A.0018.210927T1900Z-210928T1800Z/
Southern Mono County-
928 AM PDT Sun Sep 26 2021

...FIRE WEATHER WATCH NOW IN EFFECT FROM MONDAY AFTERNOON THROUGH
TUESDAY MORNING FOR GUSTY WINDS AND LOW HUMIDITY FOR SOUTHERN MONO
COUNTY...

* Changes...Extended timing into Tuesday morning.

* Affected Area...Fire Zone 274 Southern Mono County.

* Winds...Southwest to West 10 to 20 mph with gusts up to 35 mph.

* Humidity...10-15% along and east of US-395. 15-20% west of US- 
  395.

* Duration...up to 3 hours.

* Impacts...The combination of gusty winds and low humidity can
  cause fire to rapidly grow in size and intensity before first
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

http://weather.gov/reno
4 follow-up statements
539 
WWUS85 KREV 271056
RFWREV

URGENT - FIRE WEATHER MESSAGE
National Weather Service Reno NV
356 AM PDT Mon Sep 27 2021

CAZ274-272300-
/O.UPG.KREV.FW.A.0018.210927T1900Z-210928T1800Z/
/O.EXB.KREV.FW.W.0018.210927T1800Z-210929T0300Z/
Southern Mono County-
356 AM PDT Mon Sep 27 2021

...RED FLAG WARNING IN EFFECT FROM 11 AM THIS MORNING TO 8 PM PDT
TUESDAY FOR GUSTY WINDS AND LOW HUMIDITY FOR SOUTHERN MONO COUNTY...

The National Weather Service in Reno has upgraded the Fire Weather 
Watch to a Red Flag Warning for gusty winds and low humidity, which 
is in effect from 11 AM this morning to 8 PM PDT Tuesday. 

* Changes....Upgraded Fire Weather Watch to a Red Flag Warning.

* Affected Area...Fire Zone 274 Southern Mono County.

* Winds...Southwest 10 to 20 mph with gusts up to 40 mph shifting 
  North-Northeast 15-25 mph behind the cold front Tuesday with gusts 
  up to 40 mph particularly though the Chalfant Valley.
 
* Humidity...10-15% along and east of US-395. 15-20% west of US-395.

* Duration...3-6 hours.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

CAZ272-272300-
/O.CON.KREV.FW.W.0018.000000T0000Z-210928T1200Z/
Greater Lake Tahoe and Truckee Area-
356 AM PDT Mon Sep 27 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 AM PDT TUESDAY FOR
GUSTY WINDS AND LOW HUMIDITY FOR THE GREATER LAKE TAHOE TRUCKEE
AREA...

* Changes...No changes.

* Affected Area...Fire Zone 272 Greater Lake Tahoe and Truckee 
  Area.

* Winds...Southwest to West 15 to 25 mph with gusts up to 40 
  mph. Wind prone areas could see gusts up to 50 mph Monday 
  night.

* Humidity...10-20%...RH will increase Monday night to near 40%.

* Duration...3 to 7 hours of critical conditions Monday 
  afternoon. Gusty winds will last for over 24 hours.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

NVZ420-421-272300-
/O.CON.KREV.FW.W.0018.210927T1800Z-210928T1200Z/
Northern Sierra Front including Carson City, Douglas, Storey,
Southern Washoe, Western Lyon, and Far Southern Lassen Counties-
Southern Sierra Front including Alpine, Northern Mono, Southern
Lyon, and Western Mineral Counties-
356 AM PDT Mon Sep 27 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM THIS MORNING TO
5 AM PDT TUESDAY FOR GUSTY WINDS AND LOW HUMIDITY FOR THE SIERRA
FRONT...

* Changes...No Changes.

* Affected Area...Fire Zone 420 Northern Sierra Front including 
  Carson City, Douglas, Storey, Southern Washoe, Western Lyon, 
  and Far Southern Lassen Counties, Fire Zone 421 Southern 
  Sierra Front including Alpine, Northern Mono, Southern Lyon 
  and and Western Mineral Counties.

* Winds...Southwest to West 15 to 25 mph with gusts up to 40 
  mph. Wind prone areas could see gusts up to 50 mph Monday 
  night.

* Humidity...10-15% along and east of US-395. 15-20% west of US- 
  395. RH will increase Monday night to near 40%.

* Duration...3 to 7 hours of critical conditions Monday 
  afternoon. Gusty winds will last for over 18 hours.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

CAZ270-271-278-NVZ423-429-458-272300-
/O.CON.KREV.FW.W.0018.210927T1800Z-210928T0600Z/
Surprise Valley California-
Western Lassen, Eastern Plumas, and Eastern Sierra Counties-
Eastern Lassen County-West Humboldt Basin in Pershing County-
Lahontan Basin including Churchill and Eastern Mineral Counties-
Northern Washoe County-
356 AM PDT Mon Sep 27 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM THIS MORNING TO
11 PM PDT THIS EVENING FOR GUSTY WINDS AND LOW HUMIDITY FOR
NORTHEAST CALIFORNIA AND WESTERN NEVADA...

* Changes...No changes.

* Affected Area...Fire Zone 270 Surprise Valley California, Fire 
  Zone 271 Western Lassen, Eastern Plumas, and Eastern Sierra 
  Counties, Fire Zone 278 Eastern Lassen County, Fire Zone 423 
  West Humboldt Basin in Pershing County, Fire Zone 429 Lahontan 
  Basin including Churchill and Eastern Mineral Counties and 
  Fire Zone 458 Northern Washoe County.

* Winds...Southwest to West 15 to 25 mph with gusts up to 40 
  mph. Wind prone areas could see gusts up to 50 mph Monday 
  evening.

* Humidity...10-15% along and east of US-395. 15-20% west of US- 
  395. RH will increase Monday evening to near 50%.

* Duration...3 to 7 hours of critical conditions Monday 
  afternoon. Gusty winds will last for over 12 hours.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

http://weather.gov/reno
127 
WWUS85 KREV 272054
RFWREV

URGENT - FIRE WEATHER MESSAGE
National Weather Service Reno NV
154 PM PDT Mon Sep 27 2021

CAZ274-282100-
/O.CON.KREV.FW.W.0018.000000T0000Z-210929T0300Z/
Southern Mono County-
154 PM PDT Mon Sep 27 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM PDT TUESDAY FOR
GUSTY WINDS AND LOW HUMIDITY FOR SOUTHERN MONO COUNTY...

* Changes....None.

* Affected Area...Fire Zone 274 Southern Mono County.

* Winds...Southwest 10 to 20 mph with gusts up to 35 mph through
  tonight shifting North-Northeast 15-25 mph behind the cold 
  front Tuesday with gusts up to 40 mph particularly though the 
  Chalfant Valley.

* Humidity...10-15% along and east of US-395. 15-20% west of US- 
  395.

* Duration...3-6 hours.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

CAZ272-281200-
/O.CON.KREV.FW.W.0018.000000T0000Z-210928T1200Z/
Greater Lake Tahoe and Truckee Area-
154 PM PDT Mon Sep 27 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 AM PDT TUESDAY FOR
GUSTY WINDS AND LOW HUMIDITY FOR THE GREATER LAKE TAHOE TRUCKEE
AREA...

* Changes...No changes.

* Affected Area...Fire Zone 272 Greater Lake Tahoe and Truckee 
  Area.

* Winds...Southwest to West 15 to 25 mph with gusts up to 40 mph.
  Wind prone areas could see gusts up to 50 mph tonight.

* Humidity...10-20%...RH will increase tonight to near 40%.

* Duration...3 to 7 hours of critical conditions this afternoon 
  with continued gusty winds tonight.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

NVZ420-421-281200-
/O.CON.KREV.FW.W.0018.000000T0000Z-210928T1200Z/
Northern Sierra Front including Carson City, Douglas, Storey,
Southern Washoe, Western Lyon, and Far Southern Lassen Counties-
Southern Sierra Front including Alpine, Northern Mono, Southern
Lyon, and Western Mineral Counties-
154 PM PDT Mon Sep 27 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 AM PDT TUESDAY FOR
GUSTY WINDS AND LOW HUMIDITY FOR THE SIERRA FRONT...

* Changes...No Changes.

* Affected Area...Fire Zone 420 Northern Sierra Front including 
  Carson City, Douglas, Storey, Southern Washoe, Western Lyon, 
  and Far Southern Lassen Counties, Fire Zone 421 Southern 
  Sierra Front including Alpine, Northern Mono, Southern Lyon 
  and and Western Mineral Counties.

* Winds...Southwest to West 15 to 25 mph with gusts up to 40 mph.
  Wind prone areas could see gusts up to 50 mph tonight.

* Humidity...10-15% along and east of US-395. 15-20% west of US-
  395. RH will increase tonight to near 40%.

* Duration...3 to 7 hours of critical conditions this afternoon
  with continued gusty winds tonight.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

CAZ270-271-278-NVZ423-429-458-280600-
/O.CON.KREV.FW.W.0018.000000T0000Z-210928T0600Z/
Surprise Valley California-
Western Lassen, Eastern Plumas, and Eastern Sierra Counties-
Eastern Lassen County-West Humboldt Basin in Pershing County-
Lahontan Basin including Churchill and Eastern Mineral Counties-
Northern Washoe County-
154 PM PDT Mon Sep 27 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING FOR GUSTY WINDS AND LOW HUMIDITY FOR NORTHEAST CALIFORNIA
AND WESTERN NEVADA...

* Changes...No changes.

* Affected Area...Fire Zone 270 Surprise Valley California, Fire 
  Zone 271 Western Lassen, Eastern Plumas, and Eastern Sierra 
  Counties, Fire Zone 278 Eastern Lassen County, Fire Zone 423 
  West Humboldt Basin in Pershing County, Fire Zone 429 Lahontan 
  Basin including Churchill and Eastern Mineral Counties and 
  Fire Zone 458 Northern Washoe County.

* Winds...Southwest to West 15 to 25 mph with gusts up to 40 mph.
  Wind prone areas could see gusts up to 50 mph this evening.

* Humidity...10-15% along and east of US-395. 15-20% west of US-
  395. RH will increase this evening and overnight to near 50%.

* Duration...3 to 7 hours of critical conditions this afternoon
  with continued gusty winds tonight.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

http://weather.gov/reno
269 
WWUS85 KREV 280355
RFWREV

URGENT - FIRE WEATHER MESSAGE
National Weather Service Reno NV
855 PM PDT Mon Sep 27 2021

CAZ270-271-278-NVZ458-280500-
/O.CAN.KREV.FW.W.0018.000000T0000Z-210928T0600Z/
Surprise Valley California-
Western Lassen, Eastern Plumas, and Eastern Sierra Counties-
Eastern Lassen County-Northern Washoe County-
855 PM PDT Mon Sep 27 2021

...RED FLAG WARNING IS CANCELLED FOR GUSTY WINDS AND LOW HUMIDITY
FOR NORTHEAST CALIFORNIA AND FAR NORTHWEST NEVADA...

The National Weather Service in Reno has cancelled the Red Flag
Warning.

Moisture was increasing across northeast California and far
northwest Nevada as a cold front and light showers were arriving.
The threat for critical fire weather conditions has ended for 
fire zones 270, 271,278 and 458.

$$

CAZ272-280500-
/O.CAN.KREV.FW.W.0018.000000T0000Z-210928T1200Z/
Greater Lake Tahoe and Truckee Area-
855 PM PDT Mon Sep 27 2021

...RED FLAG WARNING IS CANCELLED FOR GUSTY WINDS AND LOW HUMIDITY
FOR THE GREATER LAKE TAHOE TRUCKEE AREA...

The National Weather Service in Reno has cancelled the Red Flag
Warning.

Moisture was increasing across the Tahoe Basin as a cold front
approached. Humidity levels will continue to rise as winds 
gradually decrease through the early morning hours Tuesday. The 
threat for critical fire weather conditions has diminished for 
fire weather zone 272.

$$

CAZ274-290300-
/O.CON.KREV.FW.W.0018.000000T0000Z-210929T0300Z/
Southern Mono County-
855 PM PDT Mon Sep 27 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM PDT TUESDAY FOR
GUSTY WINDS AND LOW HUMIDITY FOR SOUTHERN MONO COUNTY...

* Changes....None.

* Affected Area...Fire Zone 274 Southern Mono County.

* Winds...Southwest 10 to 20 mph with gusts up to 35 mph through 
  tonight shifting North-Northeast 15-25 mph behind the cold 
  front Tuesday with gusts up to 40 mph particularly though the 
  Chalfant Valley.

* Humidity...10-15% along and east of US-395. 15-20% west of US- 
  395.

* Duration...3-6 hours.

* Impacts...The combination of gusty winds and low humidity can 
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

NVZ420-421-281200-
/O.CON.KREV.FW.W.0018.000000T0000Z-210928T1200Z/
Northern Sierra Front including Carson City, Douglas, Storey,
Southern Washoe, Western Lyon, and Far Southern Lassen Counties-
Southern Sierra Front including Alpine, Northern Mono, Southern
Lyon, and Western Mineral Counties-
855 PM PDT Mon Sep 27 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 AM PDT TUESDAY FOR
GUSTY WINDS AND LOW HUMIDITY FOR THE SIERRA FRONT...

* Changes...No Changes.

* Affected Area...Fire Zone 420 Northern Sierra Front including 
  Carson City, Douglas, Storey, Southern Washoe, Western Lyon, 
  and Far Southern Lassen Counties, Fire Zone 421 Southern 
  Sierra Front including Alpine, Northern Mono, Southern Lyon 
  and and Western Mineral Counties.

* Winds...Southwest to West 15 to 25 mph with gusts up to 40 
  mph. Wind prone areas could see gusts up to 50 mph tonight.

* Humidity...15-25% along and east of US-395. 25-35% west of US-
  395. RH will increase to above 50% overnight.

* Impacts...The combination of gusty winds and dry conditions can
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

NVZ423-429-280600-
/O.CON.KREV.FW.W.0018.000000T0000Z-210928T0600Z/
West Humboldt Basin in Pershing County-
Lahontan Basin including Churchill and Eastern Mineral Counties-
855 PM PDT Mon Sep 27 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 PM PDT THIS
EVENING FOR GUSTY WINDS AND LOW HUMIDITY FOR NORTHEAST CALIFORNIA
AND WESTERN NEVADA...

* Changes...No changes.

* Affected Area...Fire Zone 423 West Humboldt Basin in Pershing 
  County and Fire Zone 429 Lahontan Basin including Churchill 
  and Eastern Mineral Counties.

* Winds...Southwest to West 15 to 25 mph with gusts up to 35 mph
  this evening then gradually decreasing to 10 to 15 mph with
  gusts to 30 mph overnight. 

* Humidity...15-25%. RH will increase to greater than 50%
  overnight.

* Impacts...The combination of gusty winds and dry conditions can
  cause fire to rapidly grow in size and intensity before first 
  responders can contain them.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid outdoor activities that can cause a spark near dry
vegetation, such as yard work, target shooting, or campfires.
Follow local fire restrictions. Check weather.gov/reno for
updates and livingwithfire.info for preparedness tips.

&&

$$

http://weather.gov/reno
987 
WWUS85 KREV 281054
RFWREV

URGENT - FIRE WEATHER MESSAGE
National Weather Service Reno NV
354 AM PDT Tue Sep 28 2021

CAZ274-281200-
/O.CAN.KREV.FW.W.0018.000000T0000Z-210929T0300Z/
Southern Mono County-
354 AM PDT Tue Sep 28 2021

...RED FLAG WARNING IS CANCELLED FOR GUSTY WINDS AND LOW HUMIDITY
FOR SOUTHERN MONO COUNTY...

The National Weather Service in Reno has cancelled the Red Flag
Warning. However, isolated areas of critical fire weather
conditions will still be possible through the Chalfant Valley as
north winds channel through the area behind the front this
afternoon.

$$

NVZ420-421-281200-
/O.CAN.KREV.FW.W.0018.000000T0000Z-210928T1200Z/
Northern Sierra Front including Carson City, Douglas, Storey,
Southern Washoe, Western Lyon, and Far Southern Lassen Counties-
Southern Sierra Front including Alpine, Northern Mono, Southern
Lyon, and Western Mineral Counties-
354 AM PDT Tue Sep 28 2021

...RED FLAG WARNING IS CANCELLED FOR GUSTY WINDS AND LOW HUMIDITY
FOR THE SIERRA FRONT...

The National Weather Service in Reno has cancelled the Red Flag
Warning. The cold front has moved through the region and humidity
has shown a significant increase.  

$$

http://weather.gov/reno

The office that day

Everything else NWS Reno, NV issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 26, 12:36 PM PDTLake Wind AdvisoryREVAlpine, El Dorado, Nevada, Placer39 hr
Sep 26, 12:36 PM PDTLake Wind AdvisoryREVChurchill, Lyon, Pershing, Washoe49 hr

Nearby

Red Flag Warnings in California, 2021Red Flag Warnings in Nevada, 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.