Alert archive / California / Red Flag Warnings in 2021

Red Flag Warning 14, NWS Reno, NV

August 16, 20217 counties in Nevada; 9 counties in California

NWS Reno, NV issued this red flag warning at Aug 16, 2021, 1:08 PM PDT for 7 counties in Nevada; 9 counties in California. It took effect at Aug 17, 2021, 11:00 AM PDT. It was in force for 11 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, 1:08 PM PDT (20:08 UTC)
In effect from
Aug 17, 2021, 11:00 AM PDT
Expired
Aug 17, 2021, 9:56 PM PDT
In force
11 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 20:08 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

Oakland, CA (KOAK), launched 12:00Z, 8.1 hours before the alert went out and 282 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, Oakland, CA at 12:00Z on 2021-08-16Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Oakland, CA at 12:00Z on 2021-08-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -42 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
1772 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-42 m²/s²
0-3 km storm-relative helicity
42 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

446 
WWUS85 KREV 162008
RFWREV

URGENT - FIRE WEATHER MESSAGE
National Weather Service Reno NV
108 PM PDT Mon Aug 16 2021

CAZ270-278-NVZ420-421-423-429-458-172015-
/O.UPG.KREV.FW.A.0013.210817T2100Z-210818T0600Z/
/O.NEW.KREV.FW.W.0014.210817T1800Z-210818T0600Z/
Surprise Valley California-Eastern Lassen County-
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-
West Humboldt Basin in Pershing County-
Lahontan Basin including Churchill and Eastern Mineral Counties-
Northern Washoe County-
108 PM PDT Mon Aug 16 2021

...RED FLAG WARNING IN EFFECT FROM 11 AM TO 11 PM PDT TUESDAY FOR
GUSTY WINDS AND LOW HUMIDITY FOR NORTHEASTERN CALIFORNIA AND
WESTERN NEVADA SIERRA FRONT AND EASTERN SIERRA...

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 Tuesday. The Fire Weather Watch is no longer
in effect.

* CHANGES...Upgraded to Red Flag Warning.

* Affected Area...Fire Zone 270 Surprise Valley California, Fire 
  Zone 278 Eastern Lassen County, 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 Western Mineral Counties, 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 15 to 25 mph with gusts to around 40 mph. 
  Higher gusts possible in wind prone areas and along exposed 
  terrain.

* Humidity...Minimum values 5 to 15 percent.

* Duration...3 to 7 hours for most locations. Up to 10 hours for 
  exposed midslopes and ridges.

* 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.

&&

$$

CAZ271-172015-
/O.UPG.KREV.FW.A.0013.210817T2100Z-210818T0600Z/
/O.NEW.KREV.FW.W.0014.210817T1800Z-210818T0600Z/
Western Lassen, Eastern Plumas, and Eastern Sierra Counties-
108 PM PDT Mon Aug 16 2021

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

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 Tuesday. The Fire Weather Watch is no longer
in effect.

* CHANGES...Upgrade to Red Flag Warning.

* Affected Area...Fire Zone 271 Western Lassen, Eastern Plumas 
  and and Eastern Sierra Counties.

* Winds...Southwest 15 to 25 mph with gusts to around 40 mph. 
  Higher gusts possible in wind prone areas and along exposed 
  terrain.

* Humidity...Minimum values 15 to 20 percent.

* Duration...3 to 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.

&&

$$

CAZ274-172015-
/O.NEW.KREV.FW.W.0014.210817T1800Z-210818T0600Z/
Southern Mono County-
108 PM PDT Mon Aug 16 2021

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

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 Tuesday.

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

* Winds...Southwest 15 to 25 mph with gusts to around 40 mph. 
  Higher gusts possible in wind prone areas and along exposed 
  terrain.

* Humidity...Minimum values 5 to 15 percent.

* Duration...3 to 7 hours for most locations. Up to 10 hours for 
  exposed midslopes and ridges.

* 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.

&&

$$

CAZ272-172015-
/O.NEW.KREV.FW.W.0014.210817T1800Z-210818T0600Z/
Greater Lake Tahoe and Truckee Area-
108 PM PDT Mon Aug 16 2021

...RED FLAG WARNING IN EFFECT FROM 11 AM TO 11 PM PDT TUESDAY FOR
GUSTY WINDS AND LOW HUMIDITY FOR GREATER LAKE TAHOE AND 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
11 AM to 11 PM PDT Tuesday.

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

* Winds...Southwest 15 to 25 mph with gusts to around 40 mph. 
  Higher gusts possible in wind prone areas and along exposed 
  terrain.

* Humidity...Minimum values 15 to 20 percent.

* Duration...3 to 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.

&&

$$

http://weather.gov/reno
2 follow-up statements
486 
WWUS85 KREV 171019
RFWREV

URGENT - FIRE WEATHER MESSAGE
National Weather Service Reno NV
319 AM PDT Tue Aug 17 2021

CAZ270-274-278-NVZ420-421-423-429-458-180600-
/O.CON.KREV.FW.W.0014.210817T1800Z-210818T0600Z/
Surprise Valley California-Southern Mono County-
Eastern Lassen County-
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-
West Humboldt Basin in Pershing County-
Lahontan Basin including Churchill and Eastern Mineral Counties-
Northern Washoe County-
319 AM PDT Tue Aug 17 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
NORTHEASTERN CALIFORNIA AND WESTERN NEVADA SIERRA FRONT AND
EASTERN SIERRA...

* CHANGES...None.

* Affected Area...Fire Zone 270 Surprise Valley California, Fire 
  Zone 274 Southern Mono County, Fire Zone 278 Eastern Lassen 
  County, 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 Western 
  Mineral Counties, 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 15 to 25 mph with gusts to around 40 mph. 
  Higher gusts possible in wind prone areas and along exposed 
  terrain.

* Humidity...Minimum values 5 to 15 percent.

* Duration...3 to 7 hours for most locations. Up to 10 hours for 
  exposed midslopes and ridges.

* 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.

&&

$$

CAZ271-272-180600-
/O.CON.KREV.FW.W.0014.210817T1800Z-210818T0600Z/
Western Lassen, Eastern Plumas, and Eastern Sierra Counties-
Greater Lake Tahoe and Truckee Area-
319 AM PDT Tue Aug 17 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
GREATER LAKE TAHOE AND TRUCKEE AREA...

* Changes...None.

* Affected Area...Fire Zone 271 Western Lassen, Eastern Plumas, 
  and Eastern Sierra Counties and Fire Zone 272 Greater Lake 
  Tahoe and Truckee Area.

* Winds...Southwest 15 to 25 mph with gusts to around 40 mph. 
  Higher gusts possible in wind prone areas and along exposed 
  terrain.

* Humidity...Minimum values 15 to 20 percent.

* Duration...3 to 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.

&&

$$

http://weather.gov/reno
249 
WWUS85 KREV 180456
RFWREV

URGENT - FIRE WEATHER MESSAGE
National Weather Service Reno NV
956 PM PDT Tue Aug 17 2021

CAZ270>272-274-278-NVZ420-421-423-429-458-180600-
/O.CAN.KREV.FW.W.0014.000000T0000Z-210818T0600Z/
Surprise Valley California-
Western Lassen, Eastern Plumas, and Eastern Sierra Counties-
Greater Lake Tahoe and Truckee Area-Southern Mono County-
Eastern Lassen County-
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-
West Humboldt Basin in Pershing County-
Lahontan Basin including Churchill and Eastern Mineral Counties-
Northern Washoe County-
956 PM PDT Tue Aug 17 2021

...RED FLAG WARNING IS CANCELLED FOR GUSTY WINDS AND LOW HUMIDITY
FOR NORTHEASTERN CALIFORNIA AND WESTERN NEVADA SIERRA FRONT AND
EASTERN SIERRA...

Winds and humidity have decreased below Red Flag Criteria. A cold
front however will continue to drop south tonight with an expected
wind shift out of the north-northeast through Wednesday.

$$

http://weather.gov/reno

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 16, 3:24 PM PDTLake Wind AdvisoryREVChurchill, Douglas, Lyon, Mineral, Pershing, Storey and 1 more31 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.