Red Flag Warning 35, NWS Medford, OR

580 
WWUS86 KMFR 270359
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
859 PM PDT Sat Aug 26 2017

...DRY, UNSTABLE AND LOCALLY BREEZY CONDITIONS EXPECTED INTO
EARLY NEXT WEEK...

.A dry, unstable air mass will move over the area the rest of
this weekend into early next week. Northeast winds could still be
locally gusty along the southwest Oregon Coast into this evening,
but these should ease Sunday and Monday. South winds are expected
to also be gusty each of the next 2 afternoons in the Shasta
Valley. This increase in dryness, instability, and localized
gusty winds through Monday will result in increased burning
intensity and the potential for rapid growth of uncontrolled new
and existing fires.

ORZ619-271300-
/O.EXP.KMFR.FW.W.0034.000000T0000Z-170827T0400Z/
/O.CON.KMFR.FW.W.0035.170827T2000Z-170828T0400Z/
/O.CON.KMFR.FW.W.0036.170828T2000Z-170829T0400Z/
Western Rogue River-Siskiyou National Forest-
859 PM PDT Sat Aug 26 2017

...RED FLAG WARNING WILL EXPIRE 9 PM PDT THIS EVENING FOR GUSTY 
WIND, LOW RELATIVE HUMIDITY, AND DRY AND UNSTABLE HAINES 6 
CONDITIONS FOR FIRE ZONE 619... 

...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM TO 9 PM PDT 
SUNDAY AND ALSO FROM 1 PM TO 9 PM PDT MONDAY FOR DRY AND UNSTABLE 
HAINES 6 WITH EXISTING FIRE FOR FIRE ZONE 619...


* Impacts: Dry and unstable Haines 6 conditions are expected 
  during the afternoons and evenings through Monday. This will 
  result in a high potential of plume dominated fire growth. 

* Affected area: In Southwest OR...Fire Weather Zone 619 from 
  the Rogue River Valley southward in Curry County, including 
  the Chetco Bar fire.

* Wind: Northeast 5 to 15 mph with gusts 15 to 25 mph into this 
  evening. Winds diminish Sunday and Monday, except during 
  maximum heating, when gusty, erratic winds will be possible. 

* Humidity: 30 to 50 percent mornings, 15 to 25 percent
  afternoons.

* View the hazard area in detail at 
  http://www.wrh.noaa.gov/map/?wfo=mfr

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. Gusty winds, low
humidity or dry, unstable conditions will create the potential
for rapid growth and spread of any new and existing fires.


&&

$$

ORZ618-271300-
/O.EXP.KMFR.FW.W.0034.000000T0000Z-170827T0400Z/
/O.CON.KMFR.FW.W.0035.170827T2000Z-170828T0400Z/
Southern Oregon Coast-
859 PM PDT Sat Aug 26 2017

...RED FLAG WARNING WILL EXPIRE AT 9 PM PDT THIS EVENING FOR 
GUSTY WIND, LOW RELATIVE HUMIDITY, AND DRY AND UNSTABLE HAINES 6 
CONDITIONS IN FIRE WEATHER ZONE 618... 

...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM TO 9 PM PDT 
SUNDAY FOR HAINES 6 WITH EXISTING FIRE FOR FIRE WEATHER ZONE 
618...

* Impacts: Dry and unstable Haines 6 conditions are expected again
  Sunday afternoon. This will result in a high potential of plume
  dominated fire growth.

* Affected area: In Southwest OR...Fire Weather Zone 618 from 
  the Rogue River Valley southward in Curry County, including 
  the Chetco Bar fire.

* Wind: Northeast 5 to 15 mph with gusts 15 to 25 mph into this 
  evening. Winds diminish Sunday, except during maximum 
  heating, when gusty, erratic winds will be possible.

* Humidity: 30 to 50 percent mornings, 15 to 25 percent
  afternoons.

* View the hazard area in detail at 
  http://www.wrh.noaa.gov/map/?wfo=mfr

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. Gusty winds, low
humidity or dry, unstable conditions will create the potential
for rapid growth and spread of any new and existing fires.

&&


$$

CAZ281-271300-
/O.EXP.KMFR.FW.W.0034.000000T0000Z-170827T0400Z/
/O.CON.KMFR.FW.W.0035.170827T2000Z-170828T0400Z/
Central Siskiyou County Including Shasta Valley-
859 PM PDT Sat Aug 26 2017

...RED FLAG WARNING WILL EXPIRE AT  9 PM PDT THIS EVENING FOR 
GUSTY WINDS AND VERY LOW RELATIVE HUMIDITY IN PORTIONS OF THE 
SHASTA VALLEY... 
...RED FLAG WARNING IN EFFECT FROM 1 PM TO 9 PM PDT SUNDAY FOR 
GUSTY WINDS AND VERY LOW RELATIVE HUMIDITY IN PORTIONS OF THE 
SHASTA VALLEY...

* Impacts: Breezy south winds and wind gusts combined with very
  low relative humidity and very high fire danger will lead to a
  high potential for rapid spread of any new fires again Sunday 
  afternoon and evening. 

* Affected area: In Northern California, much of the Shasta
  Valley in and around the town of Weed north to the Montague 
  area.

* Wind: South 10 to 15 mph with gusts 20 to 25 mph.

* Minimum Relative Humidity: 5 to 15 percent.

* View the hazard area in detail at 
  http://www.wrh.noaa.gov/map/?wfo=mfr

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A combination of gusty
wind and low relative humidity will create extreme fire growth
potential.


&&

$$

ORZ617-623-271300-
/O.CON.KMFR.FW.W.0035.170827T2000Z-170828T0400Z/
Umpqua National Forest-Southern Oregon Cascades-
859 PM PDT Sat Aug 26 2017

...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM TO 9 PM PDT 
SUNDAY FOR HAINES 6 WITH EXISTING FIRE FOR FIRE WEATHER ZONES 617 
AND 623...

* Impacts: Very dry and unstable air just above the North 
  Umpqua Complex, Falcon Complex, High Cascades Complex, and 
  North Pelican Fire will lead to a high potential for plume 
  dominated fire growth in these fire weather zones.

* Affected area: In Southwest OR...Fire Weather Zones 617 and
  623.

* Counties affected: Klamath, Douglas, and Jackson.

* Minimum Relative Humidity: 10 to 20 percent.

* View the hazard area in detail at 
  http://www.wrh.noaa.gov/map/?wfo=mfr

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. Dry, unstable
conditions will create the potential for rapid growth and spread
of any new and existing fires.

&&

$$


Visit us at www.weather.gov/medford

110 
WWUS86 KMFR 271240
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
540 AM PDT Sun Aug 27 2017

...DRY, UNSTABLE, AND LOCALLY BREEZY CONDITIONS EXPECTED TODAY
AND MONDAY...

.An exceptionally dry and unstable air mass over the area will
continue through at least Monday before moderating. This will lead
to a high potential of plume dominated fire growth today and,
possibly, Monday. South winds are expected to also be gusty this 
afternoon into this evening in the Shasta Valley. This increase in
dryness, instability, and localized gusty winds through Monday 
will result in increased burning intensity and the potential for 
rapid growth of uncontrolled new and existing fires.

ORZ616-280400-
/O.EXA.KMFR.FW.W.0035.170827T2000Z-170828T0400Z/
Umpqua Basin-
540 AM PDT Sun Aug 27 2017

...RED FLAG WARNING IN EFFECT FROM 1 PM THIS AFTERNOON TO 9 PM PDT
THIS EVENING FOR DRY AND UNSTABLE HAINES 6 CONDITIONS FOR FIRE 
WEATHER ZONE 616...

The National Weather Service in Medford has issued a Red Flag
Warning...which is in effect from 1 PM this afternoon to 9 PM PDT
this evening.

* Impacts: Very dry and unstable air across the fire weather zone,
  to include the Horse Prairie wildfire, this afternoon and 
  evening will lead to a high potential for plume dominated fire 
  growth. If the fire does become plume dominated, spot fires and 
  extreme fire behavior are likely. Use extreme caution engaging 
  wildfire today.

* Affected area: Fire Weather Zone 616 in Coos and Douglas Counties.

* Minimum Relative Humidity: 10 to 23 percent.

* Wind: Northwest 5 to 10 mph with gusts 15 mph. Stronger, gusty,
  and erratic winds will occur in and around active fires.

* View the hazard area in detail at
http://www.wrh.noaa.gov/map/?wfo=mfr

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions are
either occurring now, or will shortly. The combination of very dry
air, very dry vegetation, instability, and hot temperatures will 
create the potential for extreme fire behavior and fire growth. 

&&

$$

ORZ619-280400-
/O.CON.KMFR.FW.W.0035.170827T2000Z-170828T0400Z/
/O.CON.KMFR.FW.W.0036.170828T2000Z-170829T0400Z/
Western Rogue River-Siskiyou National Forest-
540 AM PDT Sun Aug 27 2017

...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM THIS AFTERNOON TO
9 PM PDT THIS EVENING FOR DRY AND UNSTABLE HAINES 6 CONDITIONS 
FOR FIRE ZONE 619...

...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM TO 9 PM PDT MONDAY
FOR DRY AND UNSTABLE HAINES 6 CONDITIONS FOR FIRE ZONE 619...

* Impacts: Very dry and unstable air across the fire weather zone,
  to include the Chetco Bar wildfire, this afternoon and evening 
  will lead to a high potential for plume dominated fire growth. If
  the fire does become plume dominated, spot fires and extreme 
  fire behavior are likely. Use extreme caution engaging wildfire 
  today.

* Affected area: In Southwest OR...Fire Weather Zone 619 in Curry 
  and Josephine Counties.

* Humidity: Generally 30 to 50 percent mornings, 15 to 25 percent
  afternoons and evenings.

* Wind: East 5 mph gusting to 15 mph nights and mornings, becoming
  southwest 5 to 10 mph gusting 15 mph afternoons and evenings.
  Stronger, gusty, and erratic winds will occur in and around
  active fires, especially around the time of maximum daytime
  heating.

* View the hazard area in detail at
  http://www.wrh.noaa.gov/map/?wfo=mfr

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions are
either occurring now, or will shortly. The combination of very dry
air, very dry vegetation, instability, and hot temperatures will 
create the potential for extreme fire behavior and fire growth.

$$

ORZ618-280400-
/O.CON.KMFR.FW.W.0035.170827T2000Z-170828T0400Z/
Southern Oregon Coast-
540 AM PDT Sun Aug 27 2017

...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM THIS AFTERNOON TO
9 PM PDT THIS EVENING FOR DRY AND UNSTABLE HAINES 6 CONDITIONS IN
FIRE WEATHER ZONE 618...

* Impacts: Very dry and unstable air across the fire weather zone,
  to include the Chetco Bar wildfire, this afternoon and evening 
  will lead to a high potential for plume dominated fire growth. If
  the fire does become plume dominated, spot fires and extreme 
  fire behavior are likely. Use extreme caution engaging wildfire 
  today.

* Affected area: Fire Weather Zone 618 in Curry County.

* Humidity: Generally 30 to 50 percent mornings, 15 to 25 percent
  afternoons and evenings.

* Wind: East 5 mph gusting to 15 mph nights and mornings, becoming
  southwest 5 to 10 mph gusting 15 mph afternoons and evenings.
  Stronger, gusty, and erratic winds will occur in and around
  active fires, especially around the time of maximum daytime
  heating.

* Humidity: 35 inland ridges to 100 percent coast this morning,
  then falling to 20 percent inland ridges to 50 percent coast this
  afternoon.

* View the hazard area in detail at
  http://www.wrh.noaa.gov/map/?wfo=mfr

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions are
either occurring now, or will shortly. The combination of very dry
air, very dry vegetation, instability, and hot temperatures will 
create the potential for extreme fire behavior and fire growth.

$$

CAZ281-280400-
/O.CON.KMFR.FW.W.0035.170827T2000Z-170828T0400Z/
Central Siskiyou County Including Shasta Valley-
540 AM PDT Sun Aug 27 2017

...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM THIS AFTERNOON TO
9 PM PDT THIS EVENING FOR GUSTY WINDS AND VERY LOW RELATIVE
HUMIDITY IN PORTIONS OF THE SHASTA VALLEY...

* Impacts: Breezy south winds and wind gusts combined with very low
  relative humidity and very high fire danger will lead to a high
  potential for rapid spread of any new fires again this afternoon
  and evening. 

* Affected area: In Northern California, much of the Shasta
  Valley in and around the town of Weed north to the Montague 
  area.

* Wind: South 10 to 15 mph with gusts 20 to 25 mph.

* Minimum Relative Humidity: 5 to 15 percent.

* View the hazard area in detail at
  http://www.wrh.noaa.gov/map/?wfo=mfr

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A combination of gusty
wind and low relative humidity will create extreme fire growth
potential.

$$

ORZ617-623-280400-
/O.CON.KMFR.FW.W.0035.170827T2000Z-170828T0400Z/
Umpqua National Forest-Southern Oregon Cascades-
540 AM PDT Sun Aug 27 2017

...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM THIS AFTERNOON TO
9 PM PDT THIS EVENING FOR DRY AND UNSTABLE HAINES 6 CONDITIONS FOR
FIRE WEATHER ZONES 617 AND 623...

* Impacts: Very dry and unstable air just above the North Umpqua
  Complex, Falcon Complex, High Cascades Complex, and North Pelican
  Fire will lead to a high potential for plume dominated fire
  growth in these fire weather zones. If fire does become plume 
  dominated, spot fires and extreme fire behavior are likely. Use 
  extreme caution engaging wildfire today.

* Affected area: Fire Weather Zones 617 and 623 IN Klamath,
  Douglas, Jackson, and Lane Counties.

* Minimum Relative Humidity: 12 to 22 percent.

* Winds: Southwest 5 to 10 mph with gusts 10 to 20 mph, becoming
  west and then northwest this afternoon and evening. Stronger,
  gusty, and erratic winds will occur in and around active fires,
  especially around the time of maximum daytime heating.

* View the hazard area in detail at
  http://www.wrh.noaa.gov/map/?wfo=mfr

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions are
either occurring now, or will shortly. The combination of very dry
air, very dry vegetation, instability, and hot temperatures will 
create the potential for extreme fire behavior and fire growth.

$$

BTL

Visit us at www.weather.gov/Medford

451 
WWUS86 KMFR 280400
RFWMFR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Medford OR
900 PM PDT Sun Aug 27 2017

...DRY, UNSTABLE, AND LOCALLY BREEZY CONDITIONS EXPECTED TODAY
AND MONDAY...

.An exceptionally dry and unstable air mass over the area will
continue through at least Monday before moderating. This will
lead to a high potential of plume dominated fire growth today
and, possibly, Monday. South winds are expected to also be gusty
this afternoon into this evening in the Shasta Valley. This
increase in dryness, instability, and localized gusty winds
through Monday will result in increased burning intensity and the
potential for rapid growth of uncontrolled new and existing
fires.

ORZ619-281600-
/O.EXP.KMFR.FW.W.0035.000000T0000Z-170828T0400Z/
/O.CON.KMFR.FW.W.0036.170828T2000Z-170829T0400Z/
Western Rogue River-Siskiyou National Forest-
900 PM PDT Sun Aug 27 2017

...RED FLAG WARNING WILL EXPIRE 9 PM PDT THIS EVENING FOR DRY AND
UNSTABLE HAINES 6 CONDITIONS FOR FIRE ZONE 619...

...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM TO 9 PM PDT MONDAY
FOR DRY AND UNSTABLE HAINES 6 CONDITIONS FOR FIRE ZONE 619...


* Impacts: Very dry and unstable air across the fire weather zone,
  to include the Chetco Bar wildfire Monday afternoon and evening
  will lead to a high potential for plume dominated fire growth. 
  If the fire does become plume dominated, spot fires and extreme 
  fire behavior are likely. Use extreme caution engaging wildfire 
  today. 

* Affected area: In Southwest OR...Fire Weather Zone 619 in 
  Curry and Josephine Counties. 

* Humidity: Generally 30 to 50 percent mornings, 15 to 25 
  percent afternoons and evenings. 

* Wind: East 5 to 10 mph tonight into Monday morning, becoming 
  southwest 5 to 10 mph gusting 15 mph Monday afternoon into early
  Monday evening. Stronger, gusty, and erratic winds will occur 
  in and around active fires, especially around the time of 
  maximum daytime heating. 

* View the hazard area in detail at 
  http://www.wrh.noaa.gov/map/?wfo=mfr

Precautionary/preparedness actions...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. The combination of
very dry air, very dry vegetation, instability, and hot
temperatures will create the potential for extreme fire behavior
and fire growth.

&&

$$

ORZ618-280500-
/O.EXP.KMFR.FW.W.0035.000000T0000Z-170828T0400Z/
Southern Oregon Coast-
900 PM PDT Sun Aug 27 2017

...RED FLAG WARNING WILL EXPIRE 9 PM PDT THIS EVENING FOR DRY AND
UNSTABLE HAINES 6 CONDITIONS FOR FIRE ZONE 618...

Dry and unstable conditions are expected again Monday, but with a
Haines 5.

$$

CAZ281-280500-
/O.EXP.KMFR.FW.W.0035.000000T0000Z-170828T0400Z/
Central Siskiyou County Including Shasta Valley-
900 PM PDT Sun Aug 27 2017

...RED FLAG WARNING WILL EXPIRE 9 PM PDT THIS EVENING FOR DRY AND
UNSTABLE HAINES 6 CONDITIONS FOR FIRE ZONE 281...

Dry and unstable conditions are expected again Monday, but with a
Haines 5.

$$

ORZ617-623-280500-
/O.EXP.KMFR.FW.W.0035.000000T0000Z-170828T0400Z/
Umpqua National Forest-Southern Oregon Cascades-
900 PM PDT Sun Aug 27 2017

...RED FLAG WARNING WILL EXPIRE 9 PM PDT THIS EVENING FOR DRY AND
UNSTABLE HAINES 6 CONDITIONS FOR FIRE ZONE 617 and 623...

Dry and unstable conditions are expected again Monday, but with a
Haines 5.

$$

ORZ616-280500-
/O.EXP.KMFR.FW.W.0035.000000T0000Z-170828T0400Z/
Umpqua Basin-
900 PM PDT Sun Aug 27 2017

...RED FLAG WARNING WILL EXPIRE 9 PM PDT THIS EVENING FOR DRY AND
UNSTABLE HAINES 6 CONDITIONS FOR FIRE ZONE 616...

Dry and unstable conditions are expected again Monday, but with a
Haines 5.

$$


Visit us at www.weather.gov/medford

Area Forecast Discussion
National Weather Service Medford OR
907 AM PDT Sat Aug 26 2017

.SHORT TERM...A strengthening upper ridge over the region combined
with a surface thermal trough will bring a hot and dry pattern to
the area through Monday. The thermal trough will have diurnal
fluctuations and shift inland in the afternoons today and Sunday.
Then the thermal trough will shift inland on Monday as a trough
approaches the Pacific Northwest.

Overall expect very warm conditions this weekend and Monday.
However, areas of smoke are keeping temperatures lower than they
would be if the skies were clear. Today temperatures are expected
in the lower to mid 90s for western valleys and in the upper 80s
to low 90s in valleys east of the Cascades. Temperatures will
increase further on Sunday with highs are expected to be in the
90s for most areas with some valleys reaching around 100 degrees,
including in portions of the Rogue and Shasta valleys.

Smoke will continue to be a problem with air quality impacts for
many areas in southwest Oregon and northwest California. Expect
only fluctuations in the areas of smoke through early Monday. Then
as the thermal trough moves inland, we may see an improvement in
air quality as west winds develop during the afternoon. An air
quality alert is in effect for portions of Curry, Douglas and
Klamath counties as well as Josephine and Jackson counties. Please
see the AQAMFR for details. The flow shifts to south to southwest
as the upper trough moves near the coast Tuesday. This may allow
some areas to see improvement while others will remain impacted by
smoke due to fires in southwest Oregon and northwest California.
Expect a return to a high pressure ridge and surface thermal
trough later in the week.

Dry weather continues through early next week with only a slight
chance for thunderstorms on Monday as mid level southerly moisture
circulates into the area. With an upper trough moving into the
coast on Wednesday, may also see a slight chance for thunderstorms
ahead of this system, in eastern Modoc or southeast Lake
counties. Otherwise dry weather remains in place through the week.

&&

.AVIATION...26/12 TAF CYCLE...Along the coast...A shallow marine
layer will bring brief IFR/MVFR fog/mist to the coast north of Cape
Blanco...including KOTH early this morning...before becoming VFR
again. Smoke from the Chetco Bar fire will also occasionally reduce
visibility to MVFR/IFR in and around Brookings.

Almost all inland areas will have to deal with reduced visibility
(MVFR and occasional IFR) due to wildfire smoke through the TAF
period with the thickest smoke in western Siskiyou County valleys,
the Applegate Valley and near the High Cascades/Umpqua North
complexes, where visibility could be reduced to just a few hundred
feet at times. BTL/Petrucelli

&&

.MARINE...Updated 245 AM PDT Saturday 26 August 2017...
The thermal trough will move inland today as high pressure centered
offshore strengthens. Small craft advisory level conditions will
linger today as moderate gusty winds and fresh swell gradually
diminish. Sunday through Wednesday winds and seas will remain
relatively light as the high over the Pacific continues to influence
surface conditions. The thermal trough is likely to rebuild later
next week resulting in another round of northerlies and more
hazardous seas. BTL

&&

.FIRE WEATHER...Updated 730 AM PDT Saturday, 26 August 2017...

...AN EXTENDED PERIOD OF ACTIVE BURNING CONDITIONS IS EXPECTED TODAY
INTO EARLY NEXT WEEK...

East winds and moderate RH recoveries in the area of the Chetco Bar
Fire have come in on the more tame side this morning, and expect
that east wind conditions will peak in criticality there this
morning. As winds begin to shift this afternoon and evening concern
shifts to dry and unstable conditions in the form of Haines 5-6
conditions, so the Red Flag Warning continues for portions Fire
Weather Zones 618 and 619 today through 9 PM PDT this evening.

The pattern across the area is a bit complicated, in that the
thermal trough will move inland today as surface high pressure
builds stronger from the west. Increasing southerly wind in the mid
levels related to low pressure west of California is expected to
surface in some locations today and Sunday afternoons and evenings.
High resolution model guidance, primarily the local Fire Weather
Guidance, the local WRF, and the HiResARW indicate a period of
enhanced wind in the Shasta Valley this afternoon and evening and
again Sunday. Thus, a RFW and a watch have been issued there, where
Haines 5-6 conditions are also expected.

Dryness and instability through the vertical air column from the
surface to 30kft peaks Sunday, and guidance indicates plenty of
Haines 6 potential. The forecast has been adjusted both for surface
temperatures, RH, and Haines to account for the expected smoke, so
Haines potential has been reduced some in Western Siskiyou County
and portions of SW Oregon. Input from IMETs on local expectations of
plume potential will be much appreciated for fine tuning the
forecast.

Lastly, guidance has trended away from a thunderstorm threat east of
the Cascades next week as moisture is insufficient and instability
too weak/elevated. Thus, if this trend continues, we'll be removing
mention from the forecast.

It should be noted that the very dry conditions in place with
increasing dryness continue to result in concerns for cumulative
effects of ongoing hot, dry weather across the area. Please keep
this in mind as you engage wildfires this week, as peak fire season
continues. Without the mitigating effects of smoke, we'd be
looking at daily high temperature records this week. BTL

&&

.PREV DISCUSSION... /Issued 313 AM PDT Sat Aug 26 2017/

DISCUSSION...The thermal trough continues along the coast
overnight. While offshore winds are not as strong with this event
as in the last one, warm and dry air in the coastal range will
still cause fire weather concerns in that area. A strong ridge
with 500mb height 588-590dm is now building into southern Oregon.
MOS guidance has latched on to very warm temperatures with 100
possible in the Rogue Valley. Normally, this is reasonable but the
forecast challenge today is the presence of smoke, which has
shaved 5 to 10 degrees from the forecast high. As a result, we
undercut MOS guidance for most areas today with lower to mid 90s
for the Rogue Valley whereas guidance is calling for 100-105.

Tonight the thermal trough is expected to expand north. The
atmosphere will continue to be dry but with less pressure
gradient there will be less winds in the coastal range. The
thermal trough is expected to shift slowly inland but still stay
west of the Cascades. As a result Sunday and Monday could be very
dry with warm nights. Fire Weather concerns expand inland with
very low humidity and locally stronger valley winds from the heat.
We are not as confident on the smoke coverage. Models indicate a
stronger 700mb winds out of the south and this could lead to more
high level smoke from western Siskiyou County into Josephine and
western Douglas County, but less so for Jackson County. This is a
solution we are looking at but confidence is not very high at this
point. As a result, we only nudge high temperatures down by a few
degrees and the Rogue Valley may just see upper 90s instead of
lower 100's. Also with the thermal trough moving toward the
Cascades, the atmosphere could be very unstable Sunday.

There is only subtle difference between Sunday and Monday. Even
though the center of the ridge shifts slightly east, 500mb heights
remain sufficiently elevated that highs will still be above
normal. The wild card on these two days will again be where and
how thick the smoke layers are located and this will have a
significant influence on the actual temperature.

The latest GFS and ECMWF shifts the moisture axis farther east.
Previously they both bring some 700-500mb moisture into the
Warners in Lake and Modoc Counties from Tuesday on. Tonight's run
shift the moisture further east. However, both still calls for the
short wave trough to slide up the western slope of the ridge west
of the Cascades. This scenario would lead to onshore flow into the
coastal counties and the Umpqua Basin. We are keeping moderately
breezy conditions for the Klamath and Goose Lake Basins. Overnight
temperatures in northern Klamath County could drop into the lower
40s again around the middle of next week. /FB

AVIATION...26/06Z TAF CYCLE...Along the coast...A shallow marine
layers will likely bring IFR/LIFR low clouds/fog back to the coast
north of Cape Blanco...including into OTH Saturday morning before
becoming VFR again. Right now we think the time range for LIFR/IFR
conditions will be between 14 and 16z, but confidence on the exact
timing is medium. Smoke from the Chetco Bar fire will also
occasionally reduce visibility to MVFR/IFR in and around Brookings.

Almost all inland areas will have to deal with reduced visibility
(MVFR and occasional IFR) due to wildfire smoke through the TAF
period with the thickest smoke in western Siskiyou County valleys,
the Applegate Valley and near the High Cascades/Umpqua North
complexes, where visibility could be reduced to just a few hundred
feet at times. -Petrucelli

MARINE...Updated 230 PM PDT Friday 25 August 2017...High pressure
is offshore with a thermal trough along the coast. Gales south of
Port Orford beyond 5 NM from shore will reach a peak this evening
and persist through late tonight. Meantime, small craft advisory
conditions will persist elsewhere. Winds will slacken on Saturday as
the high weakens and thermal trough moves inland. But, advisory
conditions will persist through Saturday night with gusty winds in
the outer waters and fresh swell near shore. Winds and seas will
continue to diminish Sunday into early Tuesday. Northerly winds will
trend higher again Tuesday into Friday with gales possible south of
Cape Blanco late in the week. -DW

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Fire Weather Watch from Sunday afternoon through Sunday evening
     for ORZ617>619-623.
     Red Flag Warning until 9 PM PDT this evening for ORZ618-619.

CA...Red Flag Warning from 1 PM this afternoon to 9 PM PDT this
     evening for CAZ281.
     Fire Weather Watch from Sunday afternoon through Sunday evening
     for CAZ281.

Pacific Coastal Waters...Small Craft Advisory until 5 AM PDT Sunday for PZZ370-376.
     Small Craft Advisory for hazardous seas until 8 PM PDT this
     evening for PZZ350-356.

CC/CC/CC