Red Flag Warning 20, NWS Reno, NV

782 
WWUS85 KREV 240423
RFWREV

URGENT - FIRE WEATHER MESSAGE
National Weather Service Reno NV
923 PM PDT Sun Aug 23 2020

CAZ274-241800-
/O.CAN.KREV.FW.A.0019.200824T2200Z-200825T1800Z/
/O.CON.KREV.FW.W.0020.000000T0000Z-200824T1800Z/
Southern Mono County-
923 PM PDT Sun Aug 23 2020

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 AM PDT MONDAY FOR
THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR THE EASTERN SIERRA...

* CHANGES...The fire weather watch from Monday afternoon until
  Tuesday morning has been cancelled. Current Red Flag Warning
  remains in effect through Monday morning. 

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

* Thunderstorms...Isolated thunderstorms may develop overnight,
  with faster moving storms producing lightning and limited
  rainfall. Isolated thunderstorms are possible again Monday
  afternoon but coverage is expected to be less with storms 
  ending in the evening.

* Impacts...Lightning can create new fire starts and may combine 
  with strong outflow winds to cause a fire to rapidly grow in 
  size and intensity before first responders can contain them.

* Additional Information...Storms may be a hybrid of wet and 
  dry, but the faster storm motions will likely allow for 
  lightning strikes outside of the main thunderstorm core. With 
  resources already stretched thin, any new fire starts will be 
  an issue.

* Outflow Winds...40 to 50 mph wind gusts are possible.

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.

&&

$$

NVZ421-241800-
/O.UPG.KREV.FW.A.0019.200824T2200Z-200825T1800Z/
/O.NEW.KREV.FW.W.0021.200824T2200Z-200825T1500Z/
/O.CON.KREV.FW.W.0020.000000T0000Z-200824T1800Z/
Southern Sierra Front including Alpine, Northern Mono, Southern
Lyon, and Western Mineral Counties-
923 PM PDT Sun Aug 23 2020

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 AM PDT MONDAY FOR
THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR THE SOUTHERN SIERRA
FRONT... 
...RED FLAG WARNING IN EFFECT FROM 3 PM MONDAY TO 8 AM 
PDT TUESDAY FOR THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR THE
SOUTHERN SIERRA FRONT...

The National Weather Service in Reno has issued a Red Flag
Warning for thunderstorms and strong outflow winds, which is in
effect from 3 PM Monday to 8 AM PDT Tuesday. 

* CHANGES...Upgraded the Watch to a Red Flag Warning Monday
  afternoon through early Tuesday morning. 

* Affected Area...Fire Zone 421 Southern Sierra Front including
  Southern Lyon and and Western Mineral Counties. Coverage on the
  California side is expected to be much lower.

* Thunderstorms...Isolated thunderstorms may develop overnight,
  with faster moving storms producing lightning and limited
  rainfall. Another round of thunderstorms is possible Monday and
  Monday night.

* Impacts...Lightning can create new fire starts and may combine 
  with strong outflow winds to cause a fire to rapidly grow in 
  size and intensity before first responders can contain them.

* Additional Information...Storms may be a hybrid of wet and 
  dry, but the faster storm motions will likely allow for 
  lightning strikes outside of the main thunderstorm core. With 
  resources already stretched thin, any new fire starts will be 
  an issue.

* Outflow Winds...40 to 50 mph wind gusts are possible.

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.

&&

$$

CAZ270-278-NVZ420-458-241800-
/O.NEW.KREV.FW.W.0021.200824T2200Z-200825T1500Z/
/O.CON.KREV.FW.W.0020.000000T0000Z-200824T1800Z/
Surprise Valley California-Eastern Lassen County-
Northern Sierra Front including Carson City, Douglas, Storey,
Southern Washoe, Western Lyon, and Far Southern Lassen Counties-
Northern Washoe County-
923 PM PDT Sun Aug 23 2020

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 AM PDT MONDAY FOR
THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR PORTIONS OF NORTHEAST
CALIFORNIA...THE TAHOE BASIN...AND FAR WESTERN NEVADA...
...RED FLAG WARNING IN EFFECT FROM 3 PM MONDAY TO 8 AM PDT
TUESDAY FOR THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR PORTIONS OF
NORTHEAST CALIFORNIA AND NORTHWEST NEVADA...

The National Weather Service in Reno has issued a Red Flag
Warning for thunderstorms and strong outflow winds, which is in
effect from 3 PM Monday to 8 AM PDT Tuesday.

* Changes...Upgraded the Watch to a Red Flag Warning Monday
  afternoon through early Tuesday morning. 

* 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 and Fire Zone 
  458 Northern Washoe County.

* Thunderstorms...The main period of concern for thunderstorm
  potential is overnight into Monday morning and again Monday
  afternoon through early Tuesday morning, with faster moving 
  storms producing lightning and limited rainfall.

* Impacts...Lightning can create new fire starts and may combine 
  with strong outflow winds to cause a fire to rapidly grow in 
  size and intensity before first responders can contain them.

* Additional Information...Storms may be a hybrid of wet and 
  dry, but the faster storm motions will likely allow for 
  lightning strikes outside of the main thunderstorm core. With 
  resources already stretched thin, any new fire starts will be 
  an issue.

* Outflow Winds...40 to 50 mph wind gusts are possible.

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.

&&

$$

NVZ423-429-241800-
/O.UPG.KREV.FW.A.0019.200824T2200Z-200825T1800Z/
/O.NEW.KREV.FW.W.0021.200824T2200Z-200825T1500Z/
West Humboldt Basin in Pershing County-
Lahontan Basin including Churchill and Eastern Mineral Counties-
923 PM PDT Sun Aug 23 2020

...RED FLAG WARNING IN EFFECT FROM 3 PM MONDAY TO 8 AM PDT
TUESDAY FOR THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR THE BASIN
AND RANGE AND EASTERN MINERAL COUNTY...

The National Weather Service in Reno has issued a Red Flag
Warning for thunderstorms and strong outflow winds, which is in
effect from 3 PM Monday to 8 AM PDT Tuesday. 

* Changes...Upgraded the Watch to a Red Flag Warning Monday
  afternoon through early Tuesday morning. 

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

* Thunderstorms...The main period of concern for thunderstorm 
  potential is late Monday afternoon through early Tuesday 
  morning, with faster moving storms producing lightning and 
  limited rainfall.

* Impacts...Lightning can create new fire starts and may combine 
  with strong outflow winds to cause a fire to rapidly grow in 
  size and intensity before first responders can contain them.

* Additional Information...Storms may be a hybrid of wet and 
  dry, but the faster storm motions will likely allow for 
  lightning strikes outside of the main thunderstorm core. With 
  resources already stretched thin, any new fire starts will be 
  an issue.

* Outflow Winds...

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.

&&

$$

CAZ271-272-241800-
/O.CON.KREV.FW.W.0020.000000T0000Z-200824T1800Z/
Western Lassen, Eastern Plumas, Eastern Sierra, and Eastern
Nevada Counties-Greater Lake Tahoe Area-
923 PM PDT Sun Aug 23 2020

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 11 AM PDT MONDAY FOR
THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR PORTIONS OF NORTHEAST
CALIFORNIA...THE TAHOE BASIN...AND FAR WESTERN NEVADA...

* Changes...None.

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

* Thunderstorms...The main period of concern for thunderstorm
  potential is overnight into Monday morning, with faster moving 
  storms producing lightning and limited rainfall.

* Impacts...Lightning can create new fire starts and may combine 
  with strong outflow winds to cause a fire to rapidly grow in 
  size and intensity before first responders can contain them.

* Additional Information...Storms may be a hybrid of wet and 
  dry, but the faster storm motions will likely allow for 
  lightning strikes outside of the main thunderstorm core. With 
  resources already stretched thin, any new fire starts will be 
  an issue.

* Outflow Winds...40 to 50 mph wind gusts are possible.

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

327 
WWUS85 KREV 241755
RFWREV

URGENT - FIRE WEATHER MESSAGE
National Weather Service Reno NV
1055 AM PDT Mon Aug 24 2020

CAZ270-278-NVZ420-421-458-251500-
/O.EXP.KREV.FW.W.0020.000000T0000Z-200824T1800Z/
/O.CON.KREV.FW.W.0021.200824T2200Z-200825T1500Z/
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-Northern Washoe County-
1055 AM PDT Mon Aug 24 2020

...RED FLAG WARNING REMAINS IN EFFECT FROM 3 PM THIS AFTERNOON TO
8 AM PDT TUESDAY FOR THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR
PORTIONS OF NORTHEAST CALIFORNIA...THE TAHOE BASIN...AND FAR
WESTERN NEVADA...

...RED FLAG WARNING WILL EXPIRE AT 11 AM PDT THIS MORNING FOR
THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR PORTIONS OF NORTHEAST
CALIFORNIA...THE TAHOE BASIN...AND FAR WESTERN NEVADA...

* Changes...No changes to the Red Flag Warning for Monday
  afternoon and Monday night.

* 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 and Fire Zone 458 
  Northern Washoe County.

* Thunderstorms...The main period of concern for thunderstorm
  potential is late this afternoon through early Tuesday morning,
  with faster moving storms producing lightning and limited 
  rainfall.

* Impacts...Lightning can create new fire starts and may combine 
  with strong outflow winds to cause a fire to rapidly grow in 
  size and intensity before first responders can contain them.

* Additional Information...Storms may be a hybrid of wet and 
  dry, but the faster storm motions will likely allow for 
  lightning strikes outside of the main thunderstorm core. With 
  resources already stretched thin, any new fire starts will be 
  an issue.

* Outflow Winds...40 to 50 mph wind gusts are possible.

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.

&&

$$

CAZ271-272-274-241900-
/O.EXP.KREV.FW.W.0020.000000T0000Z-200824T1800Z/
Western Lassen, Eastern Plumas, Eastern Sierra, and Eastern
Nevada Counties-Greater Lake Tahoe Area-Southern Mono County-
1055 AM PDT Mon Aug 24 2020

...RED FLAG WARNING WILL EXPIRE AT 11 AM PDT THIS MORNING FOR
THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR PORTIONS OF NORTHEAST
CALIFORNIA...THE TAHOE BASIN...AND FAR WESTERN NEVADA...

Thunderstorms that moved through the area Sunday night have
moved north of the Oregon border this morning with just a few 
lingering showers in Lassen County. 

$$

NVZ423-429-251500-
/O.CON.KREV.FW.W.0021.200824T2200Z-200825T1500Z/
West Humboldt Basin in Pershing County-
Lahontan Basin including Churchill and Eastern Mineral Counties-
1055 AM PDT Mon Aug 24 2020

...RED FLAG WARNING REMAINS IN EFFECT FROM 3 PM THIS AFTERNOON TO
8 AM PDT TUESDAY FOR THUNDERSTORMS AND STRONG OUTFLOW WINDS FOR
THE BASIN AND RANGE AND EASTERN MINERAL COUNTY...

* Changes...Upgraded the Watch to a Red Flag Warning Monday 
  afternoon through early Tuesday morning.

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

* Thunderstorms...The main period of concern for thunderstorm
  potential is late this afternoon through early Tuesday morning,
  with faster moving storms producing lightning and limited 
  rainfall.

* Impacts...Lightning can create new fire starts and may combine 
  with strong outflow winds to cause a fire to rapidly grow in 
  size and intensity before first responders can contain them.

* Additional Information...Storms may be a hybrid of wet and 
  dry, but the faster storm motions will likely allow for 
  lightning strikes outside of the main thunderstorm core. With 
  resources already stretched thin, any new fire starts will be 
  an issue.

* Outflow Winds...40 to 50 mph wind gusts are possible.

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

Area Forecast Discussion
National Weather Service Reno NV
255 PM PDT Sat Aug 22 2020

.SYNOPSIS...

Smoke and air quality concerns from California wildfires remain
through Sunday, especially north of Highway 50. Improving air
quality for many areas is possible by Monday. Thunderstorm chances
return to the eastern Sierra and western Nevada Sunday through
Tuesday, with the best chances in northeast California Sunday night
and Monday. Above average temperatures ease down some mid to late
next week.

&&

.SHORT TERM...

There are a fair number of moving parts to the forecast regarding
smoke, fire weather, and thunderstorm chances through the short
term and early into the long term. The main changes were to remove
overnight thunderstorm mention late tonight for eastern CA and to
begin pushing thunderstorm mentions out of northeast California by
Monday evening.

Deep moisture has surged into southern California and southern
Nevada as the remnant moisture from former Hurricane Genevieve
flows northward around a strong upper ridge centered just west of
the Four Corners. Of note is Palm Springs, CA with a temperature
of 106 and a dewpoint of 70 at 2:30 PM...for a lovely heat index
of 115 F. Anyway, some increase in mid and upper level moisture
is expected late tonight and Sunday morning for our region; however,
there does not appear to be any notable forcing to work on the
moisture and produce elevated convection so any chances for
thunderstorms were removed.

By late Sunday afternoon and Sunday night, the GFS/NAM upper
level progs (PV anomaly + weak elevated CAPE) and short-range
guidance (HREF/SREF) are pointing at the best upper forcing of the
next few days moving over eastern CA and western NV. With fast
motions expected from any convection Sunday night, there is a real
fire weather concern for dry lightning and new fire starts,
especially given the stretching of fire resources of late. As far
as impacts from any thunderstorms Sunday night, sudden gusts to 40
mph and cloud-to-ground lightning strikes are the primary threats.

Monday, a broad-brush low chance for morning showers and/or
thunderstorms was left in the forecast as plenty of moisture will
be in place by then with some uncertainty as to upper forcing.
However, it does look like the main upper forcing exits by sunrise
Monday so chances should be tapering and it is possible it will
wind up just being leftover altocumulus. Still, isolated to widely
scattered afternoon showers and thunderstorms are expected Monday
in the eastern Sierra and across western/west-central NV. There
are hints at more stable air working into northeast CA and the
Sierra north of I-80 behind the aforementioned wave so chances
were trimmed to the favored convergence zone downwind of Lassen
Peak Monday afternoon.

Monday night, a shearing and weakening wave aloft moves over
northern CA. However, the focus for nocturnal convection currently
looks to shift out in Nevada per models and NBM thunderstorm progs
so chances were increased there and reduced to ~7-13% for eastern
CA with mainly cloud cover expected. Meanwhile, the west-central
NV basin and range was added to the fire watches (dry lightning
and outflow winds) for Monday night into Tuesday with this in
mind. -Snyder

.LONG TERM...Tuesday through next Saturday...

Drier and more stable air is expected to work into the region for
the middle to late portion of next week. Temperatures will cool
slightly but remain a bit above average with highs generally in
the 80s for Sierra valleys and low to mid 90s for lower valleys.
With less cloud cover and drier air, the mild overnight lows early
in the week should fall off to more typical values. Breezes look
fairly ordinary in the long term. -Snyder

&&

.AVIATION...

Smoke from CA wildfires will continue to degrade visibility over the
next 24 hours, with the worst degradation expected north of Highway
50 (mostly just general haze south of Hwy 50). Surface gusts this
afternoon and evening should remain mostly in the 15-20 kt range.

Moisture increases from south to north tonight and Sunday, with
isolated to scattered thunderstorms returning to Mono-Mineral
counties Sunday afternoon before spreading farther north in the
evening and overnight into early Monday. Storms could bring
outflow gust to 35-40 kts late Sunday and Sunday night (more
sporadic overnight) along with brief, small areas of heavy rain
for higher terrain obscuration at times.

More storms are possible Monday, especially across western and
west-central NV. Smoke could thin out (although haze likely still)
considerably outside of far northeast CA as flow turns more
southerly early next week. -Snyder

&&

.FIRE WEATHER...

Fire weather watch remains in effect, although we made some
adjustments in timing to focus primarily on the nocturnal
thunderstorm potential, when higher cloud bases and faster storm
motions would increase the risk for lightning-induced fire starts.

While some storms may fire up Sunday afternoon near the Sierra and
western NV mainly south of US-50, these are likely to be isolated
and more capable of producing rain. The typical potential for
lightning strikes outside precipitation cores is always possible,
but we're not expecting an increased risk of multiple dry lightning
strikes.

As we get into Sunday evening, an upper level disturbance combined
with the remnant tropical moisture from Genevieve will increase the
potential for showers and embedded thunderstorms which could
continue overnight. At this time, the potential for this overnight
storm activity appears to favor Alpine-Douglas counties northward
across the Reno-Tahoe areas and northeast CA-northwest NV. We are
keeping a watch going for now instead of upgrading, as there are
unresolved issues as to whether the disturbance will provide
enough forcing for much thunderstorm activity. Coverage of lightning
could be sparse or even non-existent in many areas.

After this disturbance moves through Sunday night, a short break in
much of the storm activity appears likely until Monday afternoon
when isolated-scattered mainly wet showers and thunderstorms are
again possible north of Susanville-Gerlach, and from Reno-Tahoe
southward to Mineral-Mono counties.

Then for Monday night, an upper jet streak may provide additional
forcing as a shortwave ejects across northern CA, with a more
diffuse area of upper level dynamics currently favoring west central
NV, which could allow evening storms in these areas to continue
redeveloping well beyond sunset. In the past couple of days, this
favored area has varied from its current location to either far
northeast CA or northwest NV, so we have retained the watch for this
time frame for other portions of the region. While the moisture
content is high, winds aloft will push cells along at 15-20 mph,
limiting rainfall totals and increasing the threat for lightning
ignitions outside of storm cores.

We could see some breezes Tuesday afternoon well after the
storm activity clears out, but at this time they don't appear
to be stronger than a typical zephyr. However, if significant
lightning does occur, even these more common breezes would
potentially spread holdover fire starts. MJD

&&

.REV Watches/Warnings/Advisories...
NV...Fire Weather Watch from Sunday evening through Tuesday morning
     NVZ420-421-458.

     Dense Smoke Advisory until 11 AM PDT Sunday NVZ002>005.

     Fire Weather Watch from Monday evening through Tuesday morning
     NVZ423-429.

CA...Fire Weather Watch from Sunday evening through Tuesday morning
     CAZ270>272-274-278.

     Dense Smoke Advisory until 11 AM PDT Sunday CAZ070>072.

&&

For more information from the National Weather Service visit...
http://weather.gov/reno