Red Flag Warning 8, NWS Sacramento, CA

076 
WWUS86 KSTO 070210
RFWSTO

URGENT - FIRE WEATHER MESSAGE
National Weather Service Sacramento CA
710 PM PDT Wed Sep 6 2017

...ABUNDANT LIGHTNING POSSIBLE LATE TONIGHT AND THURSDAY...

A robust upper level weather system off the California coast will
move inland tonight and Thursday and bring the potential for 
scattered thunderstorms across the region. Abundant lightning 
strikes and gusty, erratic winds may accompany these 
thunderstorms. The combination of frequent lightning and very dry 
fuels may cause critical fire weather conditions for the mountains
and foothills. Some thunderstorms may drift into the northern 
Sacramento valley and bring and increase for fire starts.

CAZ213>215-263-266>269-279-071015-
/O.CAN.KSTO.FW.W.0008.000000T0000Z-170908T0600Z/
/O.NEW.KSTO.FW.W.0009.170907T1100Z-170908T0300Z/
Eastern Portion of Shasta/Trinity NF-
Burney Basin and Northeast Plateau in Shasta County Including
Northwest Lassen NF north of Lassen NP-
Northern Sacramento Valley to Southern Tehama County Line Below
1000 Ft-Southeast Edge Shasta-
Trinity NF and Western Portions of Tehama-Glenn Unit-
Northern Sierra Foothills from 1000 to 3000 Ft. Includes portions
of Shasta-Trinity and Butte Units-
Northern Motherlode From 1000 to 3000 Ft. Includes portions of
Nevada-Yuba-Placer-Amador and ElDorado Units-
Northern Sierra Including Lassen NP and Plumas and Lassen NF/S
West of the Sierra Crest (West of Evans Peak-Grizzly Peak-
Beckworth Peak)-
Northern Sierra Including the Tahoe and ElDorado NF/S West of the
Sierra Crest-Eastern Mendocino NF-
710 PM PDT Wed Sep 6 2017

...RED FLAG WARNING IS NOW IN EFFECT FROM 4 AM TO 8 PM PDT 
THURSDAY FOR ABUNDANT LIGHTNING FOR FIRE WEATHER ZONES 213, 214, 
215, 263, 266, 267, 268, 269, AND 279...

The National Weather Service in Sacramento has issued a Red Flag
Warning, which is in effect from 4 AM to 8 PM PDT Thursday. 

* THUNDERSTORMS...Scattered thunderstorms will be possible with 
  some wetting rain, especially for the mountains. Lightning may 
  strike outside of rain cores. 

* OUTFLOW WINDS...Gusty, erratic winds are expected near any
  thunderstorms that develop, up to as strong as 40 mph.

* TIMING...Late tonight into Thursday evening. The most widespread
  thunderstorms are expected Thursday afternoon in the mountains
  from an east to west line through the state from Plumas County
  northward.

* IMPACTS...any fires that develop from lightning strikes may  
  spread rapidly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning for abundant lightning means that frequent
lightning may increase fire starts for the warned area. A
combination of fire starts from lightning and gusty strong
outflow winds in thunderstorms can contribute to extreme fire
behavior.

&&

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$$

Area Forecast Discussion
National Weather Service Sacramento CA
401 AM PDT Wed Sep 6 2017

.SYNOPSIS...
Cool down continues this week into Thursday. Shower and
thunderstorm chances for the next several days, especially over
the mountains. Temperatures warming back up for the weekend.

&&

.DISCUSSION...
Moisture continues to stream up from the southeast with a few
light showers currently over the northern portion of the forecast
area while a few thunderstorms are present to the east of Mt
Lassen. Current temperatures are pretty similar to readings from
24 hours ago ranging from the upper 40s in the mountain valleys to
the mid 70s across milder portions of the Central Valley.

Another active day of mountain thunderstorms is expected as the
pattern remains relatively unchanged compared to Tuesday. The
closed low off the coast is forecast to move closer to the Bay
Area by this evening, then lift northward across NorCal tonight
and Thursday as the upstream trough approaches.

This feature will likely act on the deep moisture and elevated
instability that lies across the region resulting in an increase
in showers and thunderstorms tonight into Thursday as it tracks
north. A fire weather watch has been issued for the potential for
abundant lightning.

Trough lingers Friday with mountain shower and thunderstorm
chances continuing. It is then forecast to close off along the
central California coast by the weekend with warmer and drier
weather forecast to return.

&&

.EXTENDED DISCUSSION (Sunday THROUGH Wednesday)
A closed upper low will float around off the California coast
early next week. At this stage, it appears the low will initially
be close enough to draw monsoon moisture north along the Sierra,
but far enough that thunderstorm coverage should be isolated.
Temperatures across the region will likely be a bit warmer than
normal during this timeframe.

Toward the middle of next week, this system is projected to
finally push inland over California. There could be potential for
scattered thunderstorms as it does so, though confidence isn't
particularly high at this stage. We should begin to see another
cooling trend as this system pushes inland. Dang

&&

.AVIATION...
General VFR conditions are expected over TAF sites. HZ/FU from
wildfires has diminished some with onshore flow, but local MVFR
possible. High and mid clouds with scattered thunderstorms
possible over higher mountains between 20z and 05z. Winds remain
generally under 10 kts except in the Delta where gusts to 25-30
kts possible. Dang

&&

.STO WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from 2 PM PDT this afternoon through Thursday
evening for Burney Basin and Northeast Plateau in Shasta County
Including Northwest Lassen NF north of Lassen NP-Central
Sacramento Valley in Glenn, Colusa, Yuba, Northern Sutter, and
Butte County Below 1000 Ft-Eastern Mendocino NF-Eastern Portion
of Shasta/Trinity NF-Northern Motherlode From 1000 to 3000 Ft.
Includes portions of Nevada-Yuba-Placer-Amador and ElDorado
Units-Northern Sacramento Valley to Southern Tehama County Line
Below 1000 Ft-Northern Sierra Foothills from 1000 to 3000 Ft.
Includes portions of Shasta-Trinity and Butte Units-Northern
Sierra Including Lassen NP and Plumas and Lassen NF/S West of
the Sierra Crest (West of Evans Peak-Grizzly Peak-Beckworth
Peak)-Northern Sierra Including the Tahoe and ElDorado NF/S West
of the Sierra Crest-Southeast Edge Shasta-Trinity NF and Western
Portions of Tehama-Glenn Unit.

&&