Alert archive / Nevada / Red Flag Warnings in 2020

Red Flag Warning 21, NWS Las Vegas, NV

July 20, 2020Mohave County, Arizona; 4 counties in Nevada

NWS Las Vegas, NV issued this red flag warning at Jul 20, 2020, 11:39 AM MST for Mohave County, Arizona; 4 counties in Nevada. It was in force for 32 hr. 1 report 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 20, 2020, 11:39 AM MST (18:39 UTC)
Expired
Jul 21, 2020, 7:21 PM MST
In force
32 hr
Issued by
NWS Las Vegas, NV

Counties Mohave County, AZ, Clark County, NV, Esmeralda County, NV, Lincoln County, NV, Nye County, NV

The radar

The Las Vegas radar (KESX), 164 km from the middle of the area, began a volume at 18:43 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 21, 5:32 PM MSTTSTM WND GST 8311 Sse Blue Eagle Ranch, NVMESONET STATION TMBN2 TIMBER MTN.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Las Vegas, NV (KVEF), launched 12:00Z, 6.7 hours before the alert went out and 78 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, Las Vegas, NV at 12:00Z on 2020-07-20Temperature 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, Las Vegas, NV at 12:00Z on 2020-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 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
4348 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
45 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

975 
WWUS85 KVEF 201839
RFWVEF

URGENT - FIRE WEATHER MESSAGE
National Weather Service Las Vegas NV
1139 AM PDT Mon Jul 20 2020

.Isolated dry thunderstorms are expected both this afternoon and 
again Tuesday for much of southern Nevada and northwest Arizona. 
Due to the very dry nature of fuels in these areas as well as the 
increased potential for fire starts due to cloud to ground 
lightning, an increased wildfire risk will be present. 
Additionally, the very dry atmosphere will also result in the 
potential for gusty outflow winds with these thunderstorms which 
could aid in the wildfire spread risk and make them highly 
difficult to extinguish. 

AZZ101-102-NVZ460>466-210700-
/O.NEW.KVEF.FW.W.0021.200720T1839Z-200722T0400Z/
Lake Mead NRA/Colorado River-AZ side-
Northwest Deserts/Northwest Plateau-
Esmeralda and Nye County Deserts/CNC Dispatch-
Lincoln County/Ely Dispatch-Nye County Deserts/Las Vegas Dispatch-
Sheep Range-Spring Mountains-
Clark and SW Lincoln County Deserts/Las Vegas Dispatch-
Lake Mead NRA/Colorado River-NV side-
1139 AM PDT Mon Jul 20 2020 /1139 AM MST Mon Jul 20 2020/

...RED FLAG WARNING IN EFFECT UNTIL 9 PM TUESDAY FOR STRONG
OUTFLOW WINDS...LOW RH AND DRY THUNDERSTORMS FOR FIRE WEATHER 
ZONES 101, 102, 460, 461, 462, 463, 464, 465, AND 466...

The National Weather Service in Las Vegas has issued a Red Flag
Warning, which is in effect until 9 PM PDT Tuesday. 

* AFFECTED AREA...In Arizona, Fire weather zone 101 and 102. In 
  Nevada...Fire weather zones 460, 461, 462, 463, 464, 465, and 
  466. 

* TIMING...This afternoon and evening and again Tuesday morning 
  through the evening.

* WIND...Wind impacts will be mostly confined to thunderstorm
  outflows, which could exceed 40 mph at times and be highly
  variable.

* HUMIDITY...5-15 percent.

* HIGHEST THREAT...Across Mohave, Clark, and Lincoln counties,
  lesser threats farther west.

* THUNDERSTORMS...While isolated in nature, thunderstorms that
  develop will likely produce very little rainfall reaching the
  ground but contain cloud to ground lightning.

* IMPACTS...any thunderstorms that develop could produce lightning
  which will likely create multiple fire starts. 

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.

&&

$$


weather.gov/lasvegas
4 follow-up statements
577 
WWUS85 KVEF 210619
RFWVEF

URGENT - FIRE WEATHER MESSAGE
National Weather Service Las Vegas NV
1119 PM PDT Mon Jul 20 2020

.Isolated dry thunderstorms are expected Tuesday for much of 
southern Nevada and northwest Arizona. Due to the very dry nature 
of fuels in these areas as well as the increased potential for 
fire starts due to cloud to ground lightning, an increased 
wildfire risk will be present. Additionally, the very dry 
atmosphere will also result in the potential for gusty outflow 
winds with these thunderstorms which could aid in the wildfire 
spread risk and make them highly difficult to extinguish.

AZZ101-102-NVZ460>466-212200-
/O.CON.KVEF.FW.W.0021.000000T0000Z-200722T0400Z/
Lake Mead NRA/Colorado River-AZ side-
Northwest Deserts/Northwest Plateau-
Esmeralda and Nye County Deserts/CNC Dispatch-
Lincoln County/Ely Dispatch-Nye County Deserts/Las Vegas Dispatch-
Sheep Range-Spring Mountains-
Clark and SW Lincoln County Deserts/Las Vegas Dispatch-
Lake Mead NRA/Colorado River-NV side-
1119 PM PDT Mon Jul 20 2020 /1119 PM MST Mon Jul 20 2020/

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM PDT /9 PM MST/
TUESDAY FOR STRONG OUTFLOW WINDS...LOW RH AND DRY THUNDERSTORMS
FOR FIRE WEATHER ZONES 101, 102, 460, 461, 462, 463, 464, 465,
AND 466...

* AFFECTED AREA...In Arizona, Fire weather zone 101 and 102. In 
  Nevada...Fire weather zones 460, 461, 462, 463, 464, 465, and 
  466. 

* TIMING...Tuesday morning through the evening.

* WIND...Wind impacts will be mostly confined to thunderstorm 
  outflows, which could exceed 40 mph at times and be highly 
  variable.

* HUMIDITY...5-15 percent.

* HIGHEST THREAT...Across Mohave, Clark, and Lincoln counties, 
  lesser threats farther west.

* THUNDERSTORMS...While isolated in nature, thunderstorms that 
  develop will likely produce very little rainfall reaching the 
  ground but contain cloud to ground lightning.

* IMPACTS...any thunderstorms that develop could produce
  lightning which will likely create multiple fire starts. 

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.

&&

$$


weather.gov/lasvegas
656 
WWUS85 KVEF 211140
RFWVEF

URGENT - FIRE WEATHER MESSAGE
National Weather Service Las Vegas NV
440 AM PDT Tue Jul 21 2020

.Isolated thunderstorms with little or no rainfall are expected 
today for much of southern Nevada and northwest Arizona. An 
increased wildfire risk will be present due to lightning, gusty 
outflow winds and very dry fuels.

AZZ101-102-NVZ460>466-220400-
/O.CON.KVEF.FW.W.0021.000000T0000Z-200722T0400Z/
Lake Mead NRA/Colorado River-AZ side-
Northwest Deserts/Northwest Plateau-
Esmeralda and Nye County Deserts/CNC Dispatch-
Lincoln County/Ely Dispatch-Nye County Deserts/Las Vegas Dispatch-
Sheep Range-Spring Mountains-
Clark and SW Lincoln County Deserts/Las Vegas Dispatch-
Lake Mead NRA/Colorado River-NV side-
440 AM PDT Tue Jul 21 2020 /440 AM MST Tue Jul 21 2020/

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM PDT /9 PM MST/
THIS EVENING FOR DRY THUNDERSTORMS, STRONG OUTFLOW WINDS AND LOW
RH FOR ALL ZONES IN SOUTHERN NEVADA AND NORTHWEST ARIZONA...

* AFFECTED AREA...In Arizona, Fire weather zone 101 and 102. In 
  Nevada...Fire weather zones 460, 461, 462, 463, 464, 465, and 
  466. 

* TIMING...This morning through the evening.

* WIND...Wind impacts will be mostly confined to thunderstorm 
  outflows, which could exceed 40 mph at times and be highly 
  variable.

* HUMIDITY...5-15 percent.

* HIGHEST THREAT...Across Mohave, Clark, and Lincoln counties, 
  lesser threats farther west.

* THUNDERSTORMS...While isolated in nature, thunderstorms that 
  develop will likely produce very little rainfall reaching the 
  ground but contain cloud to ground lightning.

* IMPACTS...any thunderstorms that develop could produce 
  lightning which will likely create multiple fire starts.

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.

&&

$$


weather.gov/lasvegas
696 
WWUS85 KVEF 212055
RFWVEF

URGENT - FIRE WEATHER MESSAGE
National Weather Service Las Vegas NV
155 PM PDT Tue Jul 21 2020

.Continued risk of dry thunderstorms through this evening for all
of southern Nevada and northwest Arizona. On Wednesday, winds 
will increase during the afternoon resulting in widespread 
critical fire weather conditions for the same areas. Therefore, a
Red Flag Warning has been issued. On Thursday, a Fire Weather
Watch is in effect as another round of strong winds and low RH 
may occur for east- central Nevada.

NVZ461-220700-
/O.NEW.KVEF.FW.W.0022.200722T1800Z-200723T0400Z/
/O.NEW.KVEF.FW.A.0012.200723T1700Z-200724T0300Z/
/O.CON.KVEF.FW.W.0021.000000T0000Z-200722T0400Z/
Lincoln County/Ely Dispatch-
155 PM PDT Tue Jul 21 2020

...TODAYS RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM THIS 
EVENING FOR DRY THUNDERSTORMS, STRONG OUTFLOW WINDS AND LOW RH...

...ANOTHER RED FLAG WARNING WILL GO INTO EFFECT 11 AM TO 9 PM
WEDNESDAY FOR STRONG WINDS AND LOW RH...

...A FIRE WEATHER WATCH IS IN EFFECT FROM THURSDAY MORNING 
THROUGH THURSDAY EVENING FOR STRONG WINDS AND LOW RH...

The National Weather Service in Las Vegas has issued a new Red 
Flag Warning, which is in effect from 11 AM to 9 PM Wednesday and
a Fire Weather Watch has also been issued. This Fire Weather 
Watch is in effect from Thursday morning through Thursday evening.

* AFFECTED AREA...Nevada fire zone 461.

* WIND...Todays wind impacts will be mostly confined to
  thunderstorm outflows, which could exceed 40 mph at times and be
  highly variable. Wednesday and Thursday, afternoon sustained
  winds of 20-30 mph with gusts up to 40 mph will be possible. 

* HUMIDITY...5-15 percent.

* THUNDERSTORMS...While isolated in nature, thunderstorms that 
  develop will likely produce very little rainfall reaching the 
  ground but contain cloud to ground lightning.

* IMPACTS...any thunderstorms that develop could produce lightning
  which will likely create multiple fire starts through tonight.
  High winds and low RH values could result in the rapid spread of
  wildfires Wednesday and Thursday. Existing fires could be 
  exacerbated.
  

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.

A Fire Weather Watch means that critical fire weather conditions
are forecast to occur. Listen for later forecasts and possible
Red Flag Warnings.

&&

$$

AZZ101-102-NVZ460-462>466-220700-
/O.NEW.KVEF.FW.W.0022.200722T1800Z-200723T0400Z/
/O.CON.KVEF.FW.W.0021.000000T0000Z-200722T0400Z/
Lake Mead NRA/Colorado River-AZ side-
Northwest Deserts/Northwest Plateau-
Esmeralda and Nye County Deserts/CNC Dispatch-
Nye County Deserts/Las Vegas Dispatch-Sheep Range-
Spring Mountains-
Clark and SW Lincoln County Deserts/Las Vegas Dispatch-
Lake Mead NRA/Colorado River-NV side-
155 PM PDT Tue Jul 21 2020 /155 PM MST Tue Jul 21 2020/

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM PDT THIS EVENING
FOR DRY THUNDERSTORMS, STRONG OUTFLOW WINDS AND LOW RH FOR ALL 
FIRE ZONES IN SOUTHERN NEVADA AND NORTHWEST ARIZONA...

...ANOTHER RED FLAG WARNING WILL BE IN EFFECT FROM 11 AM TO 9 PM 
WEDNESDAY FOR STRONG WINDS AND LOW RH FOR ALL FIRE ZONES IN 
SOUTHERN NEVADA AND NORTHWEST ARIZONA...

The National Weather Service in Las Vegas has issued a new Red 
Flag Warning, which is in effect from 11 AM to 9 PM Wednesday. 

* AFFECTED AREA...In Arizona, Fire weather zone 101 and 102. In 
  Nevada...Fire weather zones 460, 461, 462, 463, 464, 465, and 
  466. 

* TIMING...Through 9 PM tonight and again Wednesday from 11 AM to
  9 PM.

* WIND...Wind impacts today will be mostly confined to
  thunderstorm outflows, which could exceed 40 mph at times and be
  highly variable. Winds Wednesday will be more widespread in
  nature, with sustained winds of 20-30 mph and gusts up to 40 mph
  possible.

* HUMIDITY...5-15 percent.

* THUNDERSTORMS...While isolated in nature, thunderstorms that 
  develop will likely produce very little rainfall reaching the 
  ground but contain cloud to ground lightning.

* IMPACTS...any thunderstorms that develop today could produce
  lightning which will likely create multiple fire starts. Strong
  winds and low RH Wednesday could result in the rapid spread of
  new wildfires or exacerbate ongoing 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.

&&

$$


weather.gov/lasvegas
699 
WWUS85 KVEF 220221
RFWVEF

URGENT - FIRE WEATHER MESSAGE
National Weather Service Las Vegas NV
721 PM PDT Tue Jul 21 2020

.Risk for dry thunderstorms this evening has ended for all of 
southern Nevada and northwest Arizona. On Wednesday, winds will 
increase during the afternoon resulting in widespread critical 
fire weather conditions for the same areas. Therefore, a Red Flag 
Warning has been issued. On Thursday, a Fire Weather Watch is in 
effect as another round of strong winds and low RH may occur for 
east- central Nevada.

NVZ461-221100-
/O.CAN.KVEF.FW.W.0021.000000T0000Z-200722T0400Z/
/O.CON.KVEF.FW.W.0022.200722T1800Z-200723T0400Z/
/O.CON.KVEF.FW.A.0012.200723T1700Z-200724T0300Z/
Lincoln County/Ely Dispatch-
721 PM PDT Tue Jul 21 2020

...RED FLAG WARNING IS CANCELLED FOR DRY THUNDERSTORMS, STRONG 
OUTFLOW WINDS AND LOW RH...

The National Weather Service in Las Vegas has cancelled the Red
Flag Warning for this evening. Earlier thunderstorms have weakened
with little threat for additional cloud to ground lightning
strikes this evening.  

...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM TO 9 PM PDT
WEDNESDAY FOR DRY THUNDERSTORMS, STRONG OUTFLOW WINDS AND LOW
RH...
...FIRE WEATHER WATCH REMAINS IN EFFECT FROM THURSDAY MORNING
THROUGH THURSDAY EVENING FOR DRY THUNDERSTORMS, STRONG OUTFLOW
WINDS AND LOW RH...

The National Weather Service in Las Vegas has issued a new Red
Flag Warning, which is in effect from 11 AM to 9 PM Wednesday and
a Fire Weather Watch has also been issued. This Fire Weather
Watch is in effect from Thursday morning through Thursday
evening.

* AFFECTED AREA...Nevada fire zone 461.

* WIND...Wednesday and Thursday, afternoon sustained winds of 
  20-30 mph with gusts up to 40 mph will be possible.

* HUMIDITY...5-15 percent.

* IMPACTS...High winds and low RH values could result in the 
  rapid spread of wildfires Wednesday and Thursday. Existing fires
  could be exacerbated. 

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.

A Fire Weather Watch means that critical fire weather conditions
are forecast to occur. Listen for later forecasts and possible
Red Flag Warnings.

&&

$$

AZZ101-102-NVZ460-462>466-221100-
/O.CAN.KVEF.FW.W.0021.000000T0000Z-200722T0400Z/
/O.CON.KVEF.FW.W.0022.200722T1800Z-200723T0400Z/
Lake Mead NRA/Colorado River-AZ side-
Northwest Deserts/Northwest Plateau-
Esmeralda and Nye County Deserts/CNC Dispatch-
Nye County Deserts/Las Vegas Dispatch-Sheep Range-
Spring Mountains-
Clark and SW Lincoln County Deserts/Las Vegas Dispatch-
Lake Mead NRA/Colorado River-NV side-
721 PM PDT Tue Jul 21 2020 /721 PM MST Tue Jul 21 2020/

...RED FLAG WARNING IS CANCELLED FOR DRY THUNDERSTORMS, STRONG
OUTFLOW WINDS AND LOW RH FOR ALL FIRE ZONES IN SOUTHERN NEVADA
AND NORTHWEST ARIZONA...

The National Weather Service in Las Vegas has cancelled the Red
Flag Warning for this evening. Earlier thunderstorms have weakened
with little threat for additional cloud to ground lightning
strikes this evening.

...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM PDT /11 AM MST/
TO 9 PM PDT /9 PM MST/ WEDNESDAY FOR DRY THUNDERSTORMS, STRONG
OUTFLOW WINDS AND LOW RH FOR ALL FIRE ZONES IN SOUTHERN NEVADA
AND NORTHWEST ARIZONA...

The National Weather Service in Las Vegas has issued a new Red
Flag Warning, which is in effect from 11 AM to 9 PM Wednesday.

* AFFECTED AREA...In Arizona, Fire weather zone 101 and 102. In 
  Nevada...Fire weather zones 460, 461, 462, 463, 464, 465, and 
  466. 

* TIMING...Wednesday from 11 AM to9 PM.
 
* WIND...Winds Wednesday will be more widespread in nature, with 
  sustained winds of 20-30 mph and gusts up to 40 mph possible. 

* HUMIDITY...5-15 percent.

* IMPACTS...any thunderstorms that develop today could produce 
  lightning which will likely create multiple fire starts. 
  Strong winds and low RH Wednesday could result in the rapid 
  spread of new wildfires or exacerbate ongoing 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.

&&

$$


weather.gov/lasvegas

Nearby

Red Flag Warnings in Nevada, 2020Red Flag Warnings in Arizona, 2020Every red flag warning in 2020

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.