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FXUS66 KMFR 200332
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
832 PM PDT Wed Sep 19 2018

.SHORT TERM...The forecast remains on track. An upper level
shortwave will shift east of the area tonight while an upper ridge
remains centered offshore. The pattern will shift to near zonal
flow aloft on Friday. Expect dry weather tonight through the day
Friday. A surface thermal trough along the coast will bring some
gusty north winds to the coast and coastal waters south of Cape
Blanco. Inland expect gusty north to northeast winds over the
coastal ridges tonight. Then breezy north winds are expected late
Thursday afternoon and evening for many areas west of the
Cascades. Then winds will weaken for areas west of the Cascades
Thursday night and Friday.

Models remain on track showing a weak upper level disturbance
and weak front moving inland over the Pacific Northwest Friday
night into Saturday morning. This disturbance may bring light
rain to the coast and into portions of the Umpqua and south-
central Cascades. Also ahead of this system breezy to gusty west
winds are expected east of the Cascades late Friday afternoon and
evening with stronger gusty west winds Saturday afternoon and
evening.

&&

.AVIATION...For the 20/00Z TAFs...VFR prevails all areas this
morning. MVFR cigs in low stratus will continue to spread onshore
along the Coos and Douglas coast inland into coastal valleys this
evening. Overnight ceilings may lower to a mix of IFR/MVFR and
persist through early Thursday morning. Inland, expect MVFR cigs to
spread into portions of the Umpqua, including KRBG, late tonight and
early Thursday morning. There is moderate confidence of MVFR cigs at
KRBG late tonight into thursday morning.  Elsewhere, expect VFR
through the period. -CC

&&

.MARINE...Updated 800 PM PDT Wednesday 19 September 2018...North
winds and steep wind-driven seas will continue through Thursday
evening south of Cape Blanco as a thermal trough remains oriented
along the coast. The thermal trough will weaken Friday and a frontal
system will move through the northern waters Friday night into
Saturday morning with some light rain possible. High pressure will
build offshore this weekend resulting in a strengthening thermal
trough. Expect steep to very steep seas and strong north winds that
could reach gale force south of Cape Blanco Sunday and Monday.
-Spilde


&&

.PREV DISCUSSION... /Issued 247 PM PDT Wed Sep 19 2018/

DISCUSSION...

A pretty quiet weather pattern will continue for the next two days
as we become wrapped up in some dry upper level zonal flow with a
shortwave trough departing to the east. The biggest concern in
the near term will be the north east(offshore) winds along the
coastal range tomorrow. Winds will peak in the sustained 15-25
mph range in the late morning to early afternoon time period on
Thursday. As a result, we'll see temperatures near Brookings and
the southern Oregon coastline push into the upper 70's, about 10
degrees warmer than average for this time of year. Across the rest
of the region, temperatures will be about 1 to 3 degrees below
normal for this time of year.

For Friday, we'll see another upper level trough and a cold front
approach the region. Since we'll be under some southwest flow,
temperatures will briefly warm ahead of the cold front.  This
cold front has a little moisture with it, so we'll have a chance
to see some rain along the coast and areas north of the Umpqua
divide. As we've seen already this September, we're only expecting
a few hundreths of rain near North Bend and those areas North of
the Umpqua divide and west of the Cascades.

As for Saturday and Sunday, this trough will start to progress
eastward and a pretty cold air mass will attempt to push into
Oregon. There is still a ridge over Nevada and warmer temperatures
in northern California, so we'll see temperatures range largely
across northern California to central Oregon. Right now WFO
Sacramento is forecasting lower 90's in Redding with WFO Portland
forecasting around 70 in Eugene. the 850 mb temperature gradient
between those cities is roughly 10 Celsius.

Eventually, we'll see a rex block setup to our west over the
Pacific next week. This in turn will result with persistent east
winds and dry weather. Temperatures will warm into the upper 70's
along the coast. Valleys west of the Cascades should see
temperatures warm into the mid to upper 80's. Somes Bar and Happy
Camp will see temperatures in the mid 90's. Overall, a pretty
significant warming trend going into next week for all locations,
 those west of the Cascades.

The models keep this rex block into next weekend (10 days away).
The GFS wants to insert a wave to help kick it out, but the ECMWF
is not showing that. Some of the GEFS members keep this rex block
going even longer. So it is possible we could be dealing with
these warmer than average temperatures and east upper level winds
into the start of October.

As for smoke during the forecast period, the Klondike, Natchez and
Delta fires are still active, but not as active compared to a few
weeks ago. The northeast offshore winds will start to push most
of the smoke over Brookings this afternoon, Thursday and again
next Monday through next Friday. Since the Klondike fire doesn't
have much fuel left to burn inside the fire lines ,according to
meteorologists on site, we shouldn't see massive amounts of smoke.
However, we could see visibilities reduced at times along the
southern Oregon coastline.

-Smith

FIRE WEATHER...Updated 2 PM PDT Wednesday, 19 September 2018...
The latest surface analysis shows the thermal trough located along
the southwest oregon coast. this is expected to remain through at
least Friday morning. This will result in a continued offshore flow
with moderate overnight recoveries tonight into Thursday morning for
the mid slopes and ridges. Right now it looks like recoveries could
end up lower Thursday night into Friday, but guidance is suggesting
wind speeds may not be as strong. Winds will peak in the sustained
15-25 mph range in the late morning to early afternoon time period
on Thursday.

The models are slower with the arrival of the cold front until
Saturday which makes sense given the front is nearly parallel to the
upper flow. Meanwhile the thermal trough will shift inland over the
westside valleys bringing warmer afternoon temperatures to the Rogue
and Illinois Valley. West winds will increase late Friday afternoon
and evening. RHs will be low enough to warrant a headline, though
there is some uncertainty regarding the magnitude of the winds and
whether or not these winds will be coincident with critical RHs.

A weak cold front could bring a few showers mainly north of Cape
Blanco along the coast and north of the Umpqua Divide and west
facing slopes of the Cascades from about Crater Lake north early
Saturday morning into Saturday afternoon. Even then it's debatable
weather or not we'll get anything measurable. Best case scenario
would be 0.03 of an inch near Reedsport and 0.01 of an inch
elsewhere. Winds could end up stronger east of the Cascades Saturday
afternoon and evening, but relative humidities should be a bit
higher.

Confidence is becoming higher we could be dealing with dry
conditions with gusty northeast winds (another thermal trough
pattern) Sunday into next Wednesday with moderate to poor overnight
recoveries possible starting Sunday night. The combination of wind
and moderate to poor overnight recoveries could be cause for concern
for the Klondike Fire Sunday night through Wednesday morning. As
always, the details on this could change given it's still a ways out
there.

Climatologically, many of our most robust east winds have occurred
during the last week of September and the first week of October, so
this certainly bears some watching.

-Petrucelli

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...None.

CA...None.

Pacific Coastal Waters...Small Craft Advisory until 11 PM PDT Thursday for PZZ356-376.

$$

CC

FXUS66 KMFR 200332
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
832 PM PDT Wed Sep 19 2018

.SHORT TERM...The forecast remains on track. An upper level
shortwave will shift east of the area tonight while an upper ridge
remains centered offshore. The pattern will shift to near zonal
flow aloft on Friday. Expect dry weather tonight through the day
Friday. A surface thermal trough along the coast will bring some
gusty north winds to the coast and coastal waters south of Cape
Blanco. Inland expect gusty north to northeast winds over the
coastal ridges tonight. Then breezy north winds are expected late
Thursday afternoon and evening for many areas west of the
Cascades. Then winds will weaken for areas west of the Cascades
Thursday night and Friday.

Models remain on track showing a weak upper level disturbance
and weak front moving inland over the Pacific Northwest Friday
night into Saturday morning. This disturbance may bring light
rain to the coast and into portions of the Umpqua and south-
central Cascades. Also ahead of this system breezy to gusty west
winds are expected east of the Cascades late Friday afternoon and
evening with stronger gusty west winds Saturday afternoon and
evening.

&&

.AVIATION...For the 20/00Z TAFs...VFR prevails all areas this
morning. MVFR cigs in low stratus will continue to spread onshore
along the Coos and Douglas coast inland into coastal valleys this
evening. Overnight ceilings may lower to a mix of IFR/MVFR and
persist through early Thursday morning. Inland, expect MVFR cigs to
spread into portions of the Umpqua, including KRBG, late tonight and
early Thursday morning. There is moderate confidence of MVFR cigs at
KRBG late tonight into thursday morning.  Elsewhere, expect VFR
through the period. -CC

&&

.MARINE...Updated 800 PM PDT Wednesday 19 September 2018...North
winds and steep wind-driven seas will continue through Thursday
evening south of Cape Blanco as a thermal trough remains oriented
along the coast. The thermal trough will weaken Friday and a frontal
system will move through the northern waters Friday night into
Saturday morning with some light rain possible. High pressure will
build offshore this weekend resulting in a strengthening thermal
trough. Expect steep to very steep seas and strong north winds that
could reach gale force south of Cape Blanco Sunday and Monday.
-Spilde


&&

.PREV DISCUSSION... /Issued 247 PM PDT Wed Sep 19 2018/

DISCUSSION...

A pretty quiet weather pattern will continue for the next two days
as we become wrapped up in some dry upper level zonal flow with a
shortwave trough departing to the east. The biggest concern in
the near term will be the north east(offshore) winds along the
coastal range tomorrow. Winds will peak in the sustained 15-25
mph range in the late morning to early afternoon time period on
Thursday. As a result, we'll see temperatures near Brookings and
the southern Oregon coastline push into the upper 70's, about 10
degrees warmer than average for this time of year. Across the rest
of the region, temperatures will be about 1 to 3 degrees below
normal for this time of year.

For Friday, we'll see another upper level trough and a cold front
approach the region. Since we'll be under some southwest flow,
temperatures will briefly warm ahead of the cold front.  This
cold front has a little moisture with it, so we'll have a chance
to see some rain along the coast and areas north of the Umpqua
divide. As we've seen already this September, we're only expecting
a few hundreths of rain near North Bend and those areas North of
the Umpqua divide and west of the Cascades.

As for Saturday and Sunday, this trough will start to progress
eastward and a pretty cold air mass will attempt to push into
Oregon. There is still a ridge over Nevada and warmer temperatures
in northern California, so we'll see temperatures range largely
across northern California to central Oregon. Right now WFO
Sacramento is forecasting lower 90's in Redding with WFO Portland
forecasting around 70 in Eugene. the 850 mb temperature gradient
between those cities is roughly 10 Celsius.

Eventually, we'll see a rex block setup to our west over the
Pacific next week. This in turn will result with persistent east
winds and dry weather. Temperatures will warm into the upper 70's
along the coast. Valleys west of the Cascades should see
temperatures warm into the mid to upper 80's. Somes Bar and Happy
Camp will see temperatures in the mid 90's. Overall, a pretty
significant warming trend going into next week for all locations,
 those west of the Cascades.

The models keep this rex block into next weekend (10 days away).
The GFS wants to insert a wave to help kick it out, but the ECMWF
is not showing that. Some of the GEFS members keep this rex block
going even longer. So it is possible we could be dealing with
these warmer than average temperatures and east upper level winds
into the start of October.

As for smoke during the forecast period, the Klondike, Natchez and
Delta fires are still active, but not as active compared to a few
weeks ago. The northeast offshore winds will start to push most
of the smoke over Brookings this afternoon, Thursday and again
next Monday through next Friday. Since the Klondike fire doesn't
have much fuel left to burn inside the fire lines ,according to
meteorologists on site, we shouldn't see massive amounts of smoke.
However, we could see visibilities reduced at times along the
southern Oregon coastline.

-Smith

FIRE WEATHER...Updated 2 PM PDT Wednesday, 19 September 2018...
The latest surface analysis shows the thermal trough located along
the southwest oregon coast. this is expected to remain through at
least Friday morning. This will result in a continued offshore flow
with moderate overnight recoveries tonight into Thursday morning for
the mid slopes and ridges. Right now it looks like recoveries could
end up lower Thursday night into Friday, but guidance is suggesting
wind speeds may not be as strong. Winds will peak in the sustained
15-25 mph range in the late morning to early afternoon time period
on Thursday.

The models are slower with the arrival of the cold front until
Saturday which makes sense given the front is nearly parallel to the
upper flow. Meanwhile the thermal trough will shift inland over the
westside valleys bringing warmer afternoon temperatures to the Rogue
and Illinois Valley. West winds will increase late Friday afternoon
and evening. RHs will be low enough to warrant a headline, though
there is some uncertainty regarding the magnitude of the winds and
whether or not these winds will be coincident with critical RHs.

A weak cold front could bring a few showers mainly north of Cape
Blanco along the coast and north of the Umpqua Divide and west
facing slopes of the Cascades from about Crater Lake north early
Saturday morning into Saturday afternoon. Even then it's debatable
weather or not we'll get anything measurable. Best case scenario
would be 0.03 of an inch near Reedsport and 0.01 of an inch
elsewhere. Winds could end up stronger east of the Cascades Saturday
afternoon and evening, but relative humidities should be a bit
higher.

Confidence is becoming higher we could be dealing with dry
conditions with gusty northeast winds (another thermal trough
pattern) Sunday into next Wednesday with moderate to poor overnight
recoveries possible starting Sunday night. The combination of wind
and moderate to poor overnight recoveries could be cause for concern
for the Klondike Fire Sunday night through Wednesday morning. As
always, the details on this could change given it's still a ways out
there.

Climatologically, many of our most robust east winds have occurred
during the last week of September and the first week of October, so
this certainly bears some watching.

-Petrucelli

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...None.

CA...None.

Pacific Coastal Waters...Small Craft Advisory until 11 PM PDT Thursday for PZZ356-376.

$$

CC



Office: PQR FXUS66 KPQR 200353 AFDPQR Area Forecast Discussion National Weather Service Portland OR 852 PM PDT Wed Sep 19 2018 .SYNOPSIS...A few showers are moving across SW Washington this evening, in association with a front dissipating over the forecast area. North coastal zones may see a few more showers Thursday as a warm front moves into Washington from the Pacific. A stronger cold front will bring a more widespread chance for rain as it sweeps across the forecast area Friday night and early Saturday. Autumn begins on Saturday, and it will feel like it with cool weather and some showers to start the weekend. Warmer and drier weather looks to return early next week. && .SHORT TERM...Tonight through Saturday...Latest radar imagery shows a few showers making their way across SW Washington this evening, mostly in eastern Cowlitz County. These are associated with a dissipating cold front moving across the area. Satellite fog product suggests that the front carried enough low-level moisture for at least some cloudiness overnight for most of the forecast area. This should hold temperatures slightly warmer than has been the case the last two nights, with temps tonight/Thu morning closer to seasonal norms. Models appear to be trending toward a drier forecast Thursday for all but the northwest corner of our CWA, so we lowered PoPs especially for inland areas. The 00z GFS suggests the best isentropic lift associated with Thursday's warm front will be over Washington and generally to the north of our forecast area. Once this warm front lifts north, there should be a bit of a break in precipitation until a cold front sweeps SE across the region Friday night/early Sat morning. Remainder of short term discussion from this afternoon is valid and unchanged. Weagle A much stronger front looks to arrive Fri afternoon and move inland through the evening and overnight hours. Guidance remains rather consistent with the front as it moves into western Washington and continues to keep the bulk of the QPF to our north. Nonetheless, it looks likely that areas north of Salem will see some rain Fri afternoon and evening, with areas further south may only see some light rain late Fri. The north coast could get between 0.25-0.50", while inland areas north of Portland could get around 0.10" and areas south of Portland will generally get less than 0.05". Cool and showery weather will likely continue into Sat as an upper trough moves across the Pac NW. This will keep temps a few degrees below normal and bring another round of showers under mostly cloudy skies. /64 .LONG TERM...Saturday night through Wednesday...The 12z GFS and 12z ECWMF are in agreement that Saturday night and Sunday, we can expect a shortwave trough to bring showers into the area for Saturday night. A steep ridge starts to develop over the area Sunday and Monday. This will be the dominant feature through the middle of next week. This ridge will likely bring at least a couple days of above seasonal temperatures, and east winds. This will keep PoPs to a minimum. /42 && .AVIATION...Patchy MVFR CIGs along the coast behind a very weak front will continue to be patchy overnight. Inland areas may see some MVFR CIGs after 12Z. Most areas should improve to VFR by around 18Z Thursday, but the north coast may remain MVFR through the day as a warm front approaches. KPDX AND APPROACHES...May see MVFR CIG after 12Z, but if so, conditions should improve to VFR by around 18Z. Bowen && .MARINE...No changes. Previous discussion...A weak front moved across the waters earlier today, with minimal impact other than a change in wind direction. NW post-frontal flow will be over the area late this afternoon and continue through 12Z Thu. Latest models show a weak warm front moving across the Washington and extreme North Oregon waters Thu morning. The 12Z NAM and GFs indicate South to Southwest 20 kt boundary layer wind near buoy 089 Thu afternoon. Will hold off on any small craft advisory for wind as duration looks to be short- lived, should models verify. Models continue to differ with the Thu night through Fri night period. A surface low forms near 48N 136W by 12Z Fri and moves toward Vancouver Island Fri and Fri night. The 12Z ECMWF has now caught up to the 12Z GFS regarding strength and timing. The NAM remains weaker and at least 5 degrees longitude more west. A small craft advisory for wind may be needed late Fri morning through the afternoon, especially if the GFS and ECMWF verify. North wind returns to the waters over the weekend and persists through early next week as high pressure again rebuilds over the northeastern Pacific. Seas will remain 3 to 5 feet through Fri morning, then build to 6 to 9 ft by Fri evening. Highest seas will in the northern half of PZZ270. Seas ease to near 5 ft Sat night and hold at that level through at least the first half of next week. Weishaar && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...None. && $$ Interact with us via social media: www.facebook.com/NWSPortland www.twitter.com/NWSPortland This discussion is for Northwest Oregon and Southwest Washington from the Cascade crest to 60 nautical miles offshore. This area is commonly referred to as the CWA or forecast area. FXUS66 KPQR 200353 AFDPQR Area Forecast Discussion National Weather Service Portland OR 852 PM PDT Wed Sep 19 2018 .SYNOPSIS...A few showers are moving across SW Washington this evening, in association with a front dissipating over the forecast area. North coastal zones may see a few more showers Thursday as a warm front moves into Washington from the Pacific. A stronger cold front will bring a more widespread chance for rain as it sweeps across the forecast area Friday night and early Saturday. Autumn begins on Saturday, and it will feel like it with cool weather and some showers to start the weekend. Warmer and drier weather looks to return early next week. && .SHORT TERM...Tonight through Saturday...Latest radar imagery shows a few showers making their way across SW Washington this evening, mostly in eastern Cowlitz County. These are associated with a dissipating cold front moving across the area. Satellite fog product suggests that the front carried enough low-level moisture for at least some cloudiness overnight for most of the forecast area. This should hold temperatures slightly warmer than has been the case the last two nights, with temps tonight/Thu morning closer to seasonal norms. Models appear to be trending toward a drier forecast Thursday for all but the northwest corner of our CWA, so we lowered PoPs especially for inland areas. The 00z GFS suggests the best isentropic lift associated with Thursday's warm front will be over Washington and generally to the north of our forecast area. Once this warm front lifts north, there should be a bit of a break in precipitation until a cold front sweeps SE across the region Friday night/early Sat morning. Remainder of short term discussion from this afternoon is valid and unchanged. Weagle A much stronger front looks to arrive Fri afternoon and move inland through the evening and overnight hours. Guidance remains rather consistent with the front as it moves into western Washington and continues to keep the bulk of the QPF to our north. Nonetheless, it looks likely that areas north of Salem will see some rain Fri afternoon and evening, with areas further south may only see some light rain late Fri. The north coast could get between 0.25-0.50", while inland areas north of Portland could get around 0.10" and areas south of Portland will generally get less than 0.05". Cool and showery weather will likely continue into Sat as an upper trough moves across the Pac NW. This will keep temps a few degrees below normal and bring another round of showers under mostly cloudy skies. /64 .LONG TERM...Saturday night through Wednesday...The 12z GFS and 12z ECWMF are in agreement that Saturday night and Sunday, we can expect a shortwave trough to bring showers into the area for Saturday night. A steep ridge starts to develop over the area Sunday and Monday. This will be the dominant feature through the middle of next week. This ridge will likely bring at least a couple days of above seasonal temperatures, and east winds. This will keep PoPs to a minimum. /42 && .AVIATION...Patchy MVFR CIGs along the coast behind a very weak front will continue to be patchy overnight. Inland areas may see some MVFR CIGs after 12Z. Most areas should improve to VFR by around 18Z Thursday, but the north coast may remain MVFR through the day as a warm front approaches. KPDX AND APPROACHES...May see MVFR CIG after 12Z, but if so, conditions should improve to VFR by around 18Z. Bowen && .MARINE...No changes. Previous discussion...A weak front moved across the waters earlier today, with minimal impact other than a change in wind direction. NW post-frontal flow will be over the area late this afternoon and continue through 12Z Thu. Latest models show a weak warm front moving across the Washington and extreme North Oregon waters Thu morning. The 12Z NAM and GFs indicate South to Southwest 20 kt boundary layer wind near buoy 089 Thu afternoon. Will hold off on any small craft advisory for wind as duration looks to be short- lived, should models verify. Models continue to differ with the Thu night through Fri night period. A surface low forms near 48N 136W by 12Z Fri and moves toward Vancouver Island Fri and Fri night. The 12Z ECMWF has now caught up to the 12Z GFS regarding strength and timing. The NAM remains weaker and at least 5 degrees longitude more west. A small craft advisory for wind may be needed late Fri morning through the afternoon, especially if the GFS and ECMWF verify. North wind returns to the waters over the weekend and persists through early next week as high pressure again rebuilds over the northeastern Pacific. Seas will remain 3 to 5 feet through Fri morning, then build to 6 to 9 ft by Fri evening. Highest seas will in the northern half of PZZ270. Seas ease to near 5 ft Sat night and hold at that level through at least the first half of next week. Weishaar && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...None. && $$ Interact with us via social media: www.facebook.com/NWSPortland www.twitter.com/NWSPortland This discussion is for Northwest Oregon and Southwest Washington from the Cascade crest to 60 nautical miles offshore. This area is commonly referred to as the CWA or forecast area.
Office: PDT FXUS66 KPDT 200533 AAA AFDPDT Area Forecast Discussion...Updated National Weather Service Pendleton OR 1033 PM PDT Wed Sep 19 2018 Updated aviation discussion .UPDATE...An upper trough remains over the area this evening though it will move off into Idaho and Montana by tomorrow morning as weak ridging develops over our area. A weak disturbance in the flow generated a few showers and a couple of thunderstorms over the East Slopes of the Washington Cascades and Simcoe Highlands earlier but those dissipated rapidly with sundown. There were also a few showers that developed over the Wallowa mountains and moved northeast towards Hells Canyon and those too dissipated with the approach of sundown. A couple of stations had measurable rain in the Simcoe Highlands but could not find any precipitation recorded in the Cascades or Wallowa county. Skies will be clear to mostly clear the rest of tonight. Winds remain at 15 to 20 mph in the Columbia Gorge and Kittitas Valley and will slowly decrease overnight. Elsewhere winds will be fairly light though models suggest winds increasing to around 10 mph in the Blue Mountain Foothills overnight. Temperatures are expected to be similar to last night and will be in the upper 30s to mid 40s in the lower elevations and in the mid 20s to mid 30s in the mountains and central Oregon. Forecast was in good shape, so the only changes were to adjust cloud cover and to remove any mention of showers or thunderstorms. Forecast update will be issued shortly. Perry && .AVIATION...06Z TAFs...Mostly clear skies with some high cirrus overnight becoming scattered cirrus during the day Thursday. Few-scattered mid level clouds at 8-15K feet possible after 15Z at all TAF sites except KRDM and KBDN. Winds generally light and diurnal outside of 10-15 kts with some higher gusts at KDLS/KPDT through 10Z-12Z tonight. KDLS will reach 10-15 kts again tomorrow 18Z-02Z. Perry && .PREV DISCUSSION... /issued 143 PM PDT Wed Sep 19 2018/ SHORT TERM...Tonight through Saturday...A west to northwest flow will continue over the region tonight as a weak shortwave passes to the north. This system will not have much impact to the forecast area other than some showers along the crest of the Washington Cascades overnight and Thursday. This will be followed by a building ridge of high pressure Thursday night and Friday in advance of the next system. The ridge will briefly bring temperatures back above normal on Friday. This next system will bring a warm front into northwest Washington Thursday night and Friday which will clip the central Washington Cascades for a slight chance of showers. This will be followed by a cold frontal passage Friday night and Saturday which will cool temperatures back down to around normal or just below normal. Precipitation with this system sill mainly be confined to the Cascades with a few showers possible over the eastern mountains Saturday afternoon and evening. LONG TERM...Sunday night through Wednesday...Still seeing significant variation in model solutions regarding the position of an upper low off California toward the end of next week, but most solutions in reasonable agreement in dry northwesterly flow over the Inland Northwest for a bulk of the extended period. Under partly cloudy skies and without any significant wind concerns, daytime highs will rise from near to just below normals Monday to slightly above normals by mid-week. Under mostly clear and calm conditions overnight lows will hover just below normals. Peck && .PRELIMINARY POINT TEMPS/POPS... PDT 42 72 45 79 / 0 0 0 0 ALW 44 72 46 79 / 0 0 0 0 PSC 39 76 41 81 / 0 0 0 0 YKM 43 73 45 78 / 0 0 10 0 HRI 40 75 42 80 / 0 0 0 0 ELN 41 71 43 77 / 0 0 10 10 RDM 34 72 36 80 / 0 0 0 0 LGD 37 69 40 78 / 0 0 0 0 GCD 39 69 41 80 / 0 0 0 0 DLS 49 74 50 79 / 0 0 10 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ 83/74/83 FXUS66 KPDT 200533 AAA AFDPDT Area Forecast Discussion...Updated National Weather Service Pendleton OR 1033 PM PDT Wed Sep 19 2018 Updated aviation discussion .UPDATE...An upper trough remains over the area this evening though it will move off into Idaho and Montana by tomorrow morning as weak ridging develops over our area. A weak disturbance in the flow generated a few showers and a couple of thunderstorms over the East Slopes of the Washington Cascades and Simcoe Highlands earlier but those dissipated rapidly with sundown. There were also a few showers that developed over the Wallowa mountains and moved northeast towards Hells Canyon and those too dissipated with the approach of sundown. A couple of stations had measurable rain in the Simcoe Highlands but could not find any precipitation recorded in the Cascades or Wallowa county. Skies will be clear to mostly clear the rest of tonight. Winds remain at 15 to 20 mph in the Columbia Gorge and Kittitas Valley and will slowly decrease overnight. Elsewhere winds will be fairly light though models suggest winds increasing to around 10 mph in the Blue Mountain Foothills overnight. Temperatures are expected to be similar to last night and will be in the upper 30s to mid 40s in the lower elevations and in the mid 20s to mid 30s in the mountains and central Oregon. Forecast was in good shape, so the only changes were to adjust cloud cover and to remove any mention of showers or thunderstorms. Forecast update will be issued shortly. Perry && .AVIATION...06Z TAFs...Mostly clear skies with some high cirrus overnight becoming scattered cirrus during the day Thursday. Few-scattered mid level clouds at 8-15K feet possible after 15Z at all TAF sites except KRDM and KBDN. Winds generally light and diurnal outside of 10-15 kts with some higher gusts at KDLS/KPDT through 10Z-12Z tonight. KDLS will reach 10-15 kts again tomorrow 18Z-02Z. Perry && .PREV DISCUSSION... /issued 143 PM PDT Wed Sep 19 2018/ SHORT TERM...Tonight through Saturday...A west to northwest flow will continue over the region tonight as a weak shortwave passes to the north. This system will not have much impact to the forecast area other than some showers along the crest of the Washington Cascades overnight and Thursday. This will be followed by a building ridge of high pressure Thursday night and Friday in advance of the next system. The ridge will briefly bring temperatures back above normal on Friday. This next system will bring a warm front into northwest Washington Thursday night and Friday which will clip the central Washington Cascades for a slight chance of showers. This will be followed by a cold frontal passage Friday night and Saturday which will cool temperatures back down to around normal or just below normal. Precipitation with this system sill mainly be confined to the Cascades with a few showers possible over the eastern mountains Saturday afternoon and evening. LONG TERM...Sunday night through Wednesday...Still seeing significant variation in model solutions regarding the position of an upper low off California toward the end of next week, but most solutions in reasonable agreement in dry northwesterly flow over the Inland Northwest for a bulk of the extended period. Under partly cloudy skies and without any significant wind concerns, daytime highs will rise from near to just below normals Monday to slightly above normals by mid-week. Under mostly clear and calm conditions overnight lows will hover just below normals. Peck && .PRELIMINARY POINT TEMPS/POPS... PDT 42 72 45 79 / 0 0 0 0 ALW 44 72 46 79 / 0 0 0 0 PSC 39 76 41 81 / 0 0 0 0 YKM 43 73 45 78 / 0 0 10 0 HRI 40 75 42 80 / 0 0 0 0 ELN 41 71 43 77 / 0 0 10 10 RDM 34 72 36 80 / 0 0 0 0 LGD 37 69 40 78 / 0 0 0 0 GCD 39 69 41 80 / 0 0 0 0 DLS 49 74 50 79 / 0 0 10 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ 83/74/83