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000
FXUS66 KOTX 230236
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
636 PM PST SAT NOV 22 2014

.SYNOPSIS...
Light rain and snow showers will pass through the southeast
tonight. Another round of rain and snow will arrive Sunday and
could make for slick conditions on area passes. The mountains
will receive another round of heavy snow Monday night into
Tuesday. A break in the active weather pattern will be possible
late in the week.


&&

.DISCUSSION...
Issued a short term Winter Weather Advisory for the Camas Prairie.
Unstable northwest flow into this area is producing moderate to
heavy snowfall above 3,000 feet in this area. Models show the
heaviest accumulations will continue through about 1000 PM this
evening. Bursts of heavy snow will result in quick accumulations
on road surfaces; it will also result in reduce visibility that
will result in hazardous travel across this area, which includes
highway 95 south of Lewiston on the Camas Prairie. /SVh


&&

.AVIATION...
00Z TAFS: A weather disturbance is moving through the region late
this afternoon and has initiated convective showers across the
southeast portion of the area...effecting mainly KLWS/KPUW through
04Z. Localized heavy showers may lower cigs/vsby for short
periods. In addition upsloping winds and a saturated boundary
layer will likely result in MVFR/IFR stratus overnight for
KGEG/KSFF/KCOE/KPUW through 15z. Another wet system will bring
widespread precipitation Sunday with a strong possibility for
several hours of snow at KGEG/KCOE/KSZT/KPUW...snow should turn
over to rain between 19-21z. The precipitation will bring
cig/vsby down to IFR and even LIFR at times through 00z Sunday.
/Tobin


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        30  38  28  37  32  43 /  10  90  30  10  50  60
Coeur d`Alene  30  38  29  37  33  41 /  10 100  50  20  60  80
Pullman        33  40  32  40  35  46 /  20 100  50  10  60  70
Lewiston       37  45  33  45  38  50 /  60  60  50  10  60  60
Colville       24  37  23  37  30  39 /  10  80  30  20  60  60
Sandpoint      30  36  29  37  31  39 /  20 100  50  30  70  80
Kellogg        32  35  31  35  32  38 /  50 100  70  20  70  90
Moses Lake     28  43  28  41  33  48 /   0  20  10  10  20  20
Wenatchee      33  42  32  41  35  46 /  10  40  10  10  20  30
Omak           27  37  26  37  30  41 /  10  50  10  20  30  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 6 AM PST Monday for Central
     Panhandle Mountains.

     Winter Weather Advisory until 10 PM PST this evening for Lewis
     and Southern Nez Perce Counties.

WA...None.
&&

$$






000
FXUS66 KOTX 230236
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
636 PM PST SAT NOV 22 2014

.SYNOPSIS...
Light rain and snow showers will pass through the southeast
tonight. Another round of rain and snow will arrive Sunday and
could make for slick conditions on area passes. The mountains
will receive another round of heavy snow Monday night into
Tuesday. A break in the active weather pattern will be possible
late in the week.


&&

.DISCUSSION...
Issued a short term Winter Weather Advisory for the Camas Prairie.
Unstable northwest flow into this area is producing moderate to
heavy snowfall above 3,000 feet in this area. Models show the
heaviest accumulations will continue through about 1000 PM this
evening. Bursts of heavy snow will result in quick accumulations
on road surfaces; it will also result in reduce visibility that
will result in hazardous travel across this area, which includes
highway 95 south of Lewiston on the Camas Prairie. /SVh


&&

.AVIATION...
00Z TAFS: A weather disturbance is moving through the region late
this afternoon and has initiated convective showers across the
southeast portion of the area...effecting mainly KLWS/KPUW through
04Z. Localized heavy showers may lower cigs/vsby for short
periods. In addition upsloping winds and a saturated boundary
layer will likely result in MVFR/IFR stratus overnight for
KGEG/KSFF/KCOE/KPUW through 15z. Another wet system will bring
widespread precipitation Sunday with a strong possibility for
several hours of snow at KGEG/KCOE/KSZT/KPUW...snow should turn
over to rain between 19-21z. The precipitation will bring
cig/vsby down to IFR and even LIFR at times through 00z Sunday.
/Tobin


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        30  38  28  37  32  43 /  10  90  30  10  50  60
Coeur d`Alene  30  38  29  37  33  41 /  10 100  50  20  60  80
Pullman        33  40  32  40  35  46 /  20 100  50  10  60  70
Lewiston       37  45  33  45  38  50 /  60  60  50  10  60  60
Colville       24  37  23  37  30  39 /  10  80  30  20  60  60
Sandpoint      30  36  29  37  31  39 /  20 100  50  30  70  80
Kellogg        32  35  31  35  32  38 /  50 100  70  20  70  90
Moses Lake     28  43  28  41  33  48 /   0  20  10  10  20  20
Wenatchee      33  42  32  41  35  46 /  10  40  10  10  20  30
Omak           27  37  26  37  30  41 /  10  50  10  20  30  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 6 AM PST Monday for Central
     Panhandle Mountains.

     Winter Weather Advisory until 10 PM PST this evening for Lewis
     and Southern Nez Perce Counties.

WA...None.
&&

$$





000
FXUS66 KOTX 230027
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
425 PM PST SAT NOV 22 2014

.SYNOPSIS...
Light rain and snow showers will pass through the southeast
tonight. Another round of rain and snow will arrive Sunday and
could make for slick conditions on area passes. The mountains
will receive another round of heavy snow Monday night into
Tuesday. A break in the active weather pattern will be possible
late in the week.



&&

.DISCUSSION...
Tonight and Sunday: The main focus for tonight will be an area of
showers associated with a vort max that is currently tracking
along the WA/OR border. As of 2PM, the circulation has crossed the
Cascades and clouds/radar echoes continue to blossom across the
lower Columbia Basin and north Oregon. This will not be an
extremely wet system but localized showers could be intense at
times given the cold and unstable air mass in place. Model trends
have been a bit further south placing the highest precipitation
chances south of a line from La Crosse to Avery...and current HRRR
runs suggest precipitation may struggle to expand north of
Lewiston. Gusty southerly flow ahead of this wave has resulted in
low 50s in the L-C Valley and observations from the Blues/Camas
Prairie suggest the best chance for any snow will be above 4500
feet. A secondary and even smaller wave will drop south from BC
bringing isolated snow showers across the northeast zones (NE
WA/Nrn ID) overnight. Again, these will be rather light.

So the question then becomes how much clearing will we see? This
becomes important because a wetter and more widespread
precipitation event arrives Sunday. This wave is currently visible
on afternoon Water Vapor near 140W off the WA Coast. The lift and
moisture will be much better with this wave and models are in
decent agreement of areas of east of a line from Colville to
Ritzville squeezing out between a tenth to three tenths of liquid.
Snow levels are the wildcard and ultimately comes down to how much
clearing occurs overnight. Our forecast is probably on the lower
end of the spectrum for snow levels and may need to be tweaked up
but would like to see how cold it gets tonight before doing so.
The best chance for lowland snow accumulations of 1-2 inches
will be in the NE valleys with lower amounts into the Upper
Columbia Basin and Spokane-CDA area. Elevations above 2500 feet
will carry the highest probabilities.  The eastern mountains will
receive another 2-5 inches with locally higher amounts in the
Central Panhandle Mtns and this was covered in the latest winter
weather advisory. Snow will also continue along the Cascade Crest
but taper off quickly in the lee of the Cascades where shadowing
normally occurs.

For Sunday, clouds and light precipitation will materialize
throughout the morning and intensify over the ID Panhandle and far
eastern reaches of WA (and Cascade Crest) Sunday afternoon. This
is another reason for lacking valley accumulations but mountain
passes are likely to experience snow covered roads and hazardous
travel. /sb

Sunday night through Tuesday night...Through this period of the
forecast high pressure will build in the eastern Pacific out
between 130-132W. This will keep northwest flow over the region
through Monday night then becoming west-northwest Monday night and
Tuesday. This flow pattern will allow a series of weak
disturbances to track over the ridge and drop through the forecast
area through the entire period.

Northwest flow Sunday night and Monday will keep orographic
showers across the eastern mountains...and some slop over showers
across the Cascade crest. Snow levels for the Panhandle range
from 3K feet across the south to just under 2k for the north
Panhandle. Some of the higher mountains south of I-90 could pick
up 3-4 inches of snow by Monday morning with much less for the
north Panhandle...with 1-3 inches near the Cascade crest.
Otherwise expect a dry forecast with temperatures near persistence
and near seasonal averages.

Monday night through Tuesday night the weather will move through
the region. Model guidance shows this system to have decent
moisture with PWATs going up to .85 or so. Isentropic up-glide
will increase just after 06z and quickly push across the northern
zones and finally into the eastern up-slope areas by morning.
Nothing in the way of a cold front passage will be available to
increase forcing so lift just by isentropic up-glide and
orographics. Still the models are spitting out some pretty hefty
precipitation totals. The lower east slopes and the deep basin
should get shadowed out by the Cascades but will still be able to
squeeze out a little rain.

Snow levels start out around 4K feet across the south and 2K
feet across the north but with south-southwest lower level winds
and moderate warm air advection snow levels will lift above 5k
feet across the south and above 3-3.5k feet across the north by
early Tuesday afternoon. This will result in most of the valleys
below 3k feet getting rain with snow in the mountains. 24-36 hour
snow amounts could be as high as 8-12 inches near the Cascade
crest...5-9 inches for the northeast mountains and Idaho Panhandle
mountains by Wednesday morning. A lot of these amounts will be
very dependent on just how fast the temperatures warm up during
the day Tuesday.

Tuesday will seem quite balmy with temperatures rising into the
upper 30s to lower 50s. Southwest will be on the increase again
Tuesday and Tuesday night with sustain 10-20 mph and gust 25-30
mph. /Tobin

Wednesday through Saturday...The busiest travel day of the year
will be unseasonably warm across the region as gusty southwest
winds keep the atmosphere well mixed. Temperatures will be in the
40s with low 50s possible in the southern valleys. This will keep
any precipitation in liquid form except for the high peaks. Snow
levels will start to drop as winds shift to the west during the
evening hours then become northerly overnight. Medium range models
are in general agreement on shortwave energy riding along a rather
flat ridge with the main threat of precipitation across the
northern zones on Wednesday. By Thanksgiving Day the track of the
band of moisture sinks as far south as the Palouse per the 12Z GFS
while the ECMWF keeps it more to the north. The 12Z GFS also
brings colder temps farther south with the possibility of some
light snow for the I-90 corridor. As I type this, the 18Z run of
the GFS is coming in warmer so there is quite a bit of uncertainty
as to p-type. The general trend will be cooling temperatures in
northerly flow for Friday and Friday night, then a gradual warming
as winds again shift to the southwest ahead of the next warm front
that could affect the Inland Northwest over the weekend. Warm air
moving in over the colder air entrenched at the surface could mean
the possibility of some mixed precipitation. Models disagree on
the southerly extend of the cold air at the surface and also on
the timing of this feature so for now we will keep sleet/FZRA out
of the weather grids. /Kelch

&&

.AVIATION...
00Z TAFS: A weather disturbance is moving through the region late
this afternoon and has initiated convective showers across the
southeast portion of the area...effecting mainly KLWS/KPUW through
04Z. Localized heavy showers may lower cigs/vsby for short
periods. In addition upsloping winds and a saturated boundary
layer will likely result in MVFR/IFR stratus overnight for
KGEG/KSFF/KCOE/KPUW through 15z. Another wet system will bring
widespread precipitation Sunday with a strong possibility for
several hours of snow at KGEG/KCOE/KSZT/KPUW...snow should turn
over to rain between 19-21z. The precipitation will bring
cig/vsby down to IFR and even LIFR at times through 00z Sunday.
/Tobin



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        30  38  28  37  32  43 /  10  90  30  10  50  60
Coeur d`Alene  30  38  29  37  33  41 /  10 100  50  20  60  80
Pullman        33  40  32  40  35  46 /  20 100  50  10  60  70
Lewiston       37  45  33  45  38  50 /  60  60  50  10  60  60
Colville       24  37  23  37  30  39 /  10  80  30  20  60  60
Sandpoint      30  36  29  37  31  39 /  20 100  50  30  70  80
Kellogg        32  35  31  35  32  38 /  50 100  70  20  70  90
Moses Lake     28  43  28  41  33  48 /  10  20  10  10  20  20
Wenatchee      33  42  32  41  35  46 /  10  40  10  10  20  30
Omak           27  37  26  37  30  41 /  10  50  10  20  30  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 6 AM PST Monday for Central
     Panhandle Mountains.

WA...None.
&&

$$






000
FXUS66 KOTX 230027
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
425 PM PST SAT NOV 22 2014

.SYNOPSIS...
Light rain and snow showers will pass through the southeast
tonight. Another round of rain and snow will arrive Sunday and
could make for slick conditions on area passes. The mountains
will receive another round of heavy snow Monday night into
Tuesday. A break in the active weather pattern will be possible
late in the week.



&&

.DISCUSSION...
Tonight and Sunday: The main focus for tonight will be an area of
showers associated with a vort max that is currently tracking
along the WA/OR border. As of 2PM, the circulation has crossed the
Cascades and clouds/radar echoes continue to blossom across the
lower Columbia Basin and north Oregon. This will not be an
extremely wet system but localized showers could be intense at
times given the cold and unstable air mass in place. Model trends
have been a bit further south placing the highest precipitation
chances south of a line from La Crosse to Avery...and current HRRR
runs suggest precipitation may struggle to expand north of
Lewiston. Gusty southerly flow ahead of this wave has resulted in
low 50s in the L-C Valley and observations from the Blues/Camas
Prairie suggest the best chance for any snow will be above 4500
feet. A secondary and even smaller wave will drop south from BC
bringing isolated snow showers across the northeast zones (NE
WA/Nrn ID) overnight. Again, these will be rather light.

So the question then becomes how much clearing will we see? This
becomes important because a wetter and more widespread
precipitation event arrives Sunday. This wave is currently visible
on afternoon Water Vapor near 140W off the WA Coast. The lift and
moisture will be much better with this wave and models are in
decent agreement of areas of east of a line from Colville to
Ritzville squeezing out between a tenth to three tenths of liquid.
Snow levels are the wildcard and ultimately comes down to how much
clearing occurs overnight. Our forecast is probably on the lower
end of the spectrum for snow levels and may need to be tweaked up
but would like to see how cold it gets tonight before doing so.
The best chance for lowland snow accumulations of 1-2 inches
will be in the NE valleys with lower amounts into the Upper
Columbia Basin and Spokane-CDA area. Elevations above 2500 feet
will carry the highest probabilities.  The eastern mountains will
receive another 2-5 inches with locally higher amounts in the
Central Panhandle Mtns and this was covered in the latest winter
weather advisory. Snow will also continue along the Cascade Crest
but taper off quickly in the lee of the Cascades where shadowing
normally occurs.

For Sunday, clouds and light precipitation will materialize
throughout the morning and intensify over the ID Panhandle and far
eastern reaches of WA (and Cascade Crest) Sunday afternoon. This
is another reason for lacking valley accumulations but mountain
passes are likely to experience snow covered roads and hazardous
travel. /sb

Sunday night through Tuesday night...Through this period of the
forecast high pressure will build in the eastern Pacific out
between 130-132W. This will keep northwest flow over the region
through Monday night then becoming west-northwest Monday night and
Tuesday. This flow pattern will allow a series of weak
disturbances to track over the ridge and drop through the forecast
area through the entire period.

Northwest flow Sunday night and Monday will keep orographic
showers across the eastern mountains...and some slop over showers
across the Cascade crest. Snow levels for the Panhandle range
from 3K feet across the south to just under 2k for the north
Panhandle. Some of the higher mountains south of I-90 could pick
up 3-4 inches of snow by Monday morning with much less for the
north Panhandle...with 1-3 inches near the Cascade crest.
Otherwise expect a dry forecast with temperatures near persistence
and near seasonal averages.

Monday night through Tuesday night the weather will move through
the region. Model guidance shows this system to have decent
moisture with PWATs going up to .85 or so. Isentropic up-glide
will increase just after 06z and quickly push across the northern
zones and finally into the eastern up-slope areas by morning.
Nothing in the way of a cold front passage will be available to
increase forcing so lift just by isentropic up-glide and
orographics. Still the models are spitting out some pretty hefty
precipitation totals. The lower east slopes and the deep basin
should get shadowed out by the Cascades but will still be able to
squeeze out a little rain.

Snow levels start out around 4K feet across the south and 2K
feet across the north but with south-southwest lower level winds
and moderate warm air advection snow levels will lift above 5k
feet across the south and above 3-3.5k feet across the north by
early Tuesday afternoon. This will result in most of the valleys
below 3k feet getting rain with snow in the mountains. 24-36 hour
snow amounts could be as high as 8-12 inches near the Cascade
crest...5-9 inches for the northeast mountains and Idaho Panhandle
mountains by Wednesday morning. A lot of these amounts will be
very dependent on just how fast the temperatures warm up during
the day Tuesday.

Tuesday will seem quite balmy with temperatures rising into the
upper 30s to lower 50s. Southwest will be on the increase again
Tuesday and Tuesday night with sustain 10-20 mph and gust 25-30
mph. /Tobin

Wednesday through Saturday...The busiest travel day of the year
will be unseasonably warm across the region as gusty southwest
winds keep the atmosphere well mixed. Temperatures will be in the
40s with low 50s possible in the southern valleys. This will keep
any precipitation in liquid form except for the high peaks. Snow
levels will start to drop as winds shift to the west during the
evening hours then become northerly overnight. Medium range models
are in general agreement on shortwave energy riding along a rather
flat ridge with the main threat of precipitation across the
northern zones on Wednesday. By Thanksgiving Day the track of the
band of moisture sinks as far south as the Palouse per the 12Z GFS
while the ECMWF keeps it more to the north. The 12Z GFS also
brings colder temps farther south with the possibility of some
light snow for the I-90 corridor. As I type this, the 18Z run of
the GFS is coming in warmer so there is quite a bit of uncertainty
as to p-type. The general trend will be cooling temperatures in
northerly flow for Friday and Friday night, then a gradual warming
as winds again shift to the southwest ahead of the next warm front
that could affect the Inland Northwest over the weekend. Warm air
moving in over the colder air entrenched at the surface could mean
the possibility of some mixed precipitation. Models disagree on
the southerly extend of the cold air at the surface and also on
the timing of this feature so for now we will keep sleet/FZRA out
of the weather grids. /Kelch

&&

.AVIATION...
00Z TAFS: A weather disturbance is moving through the region late
this afternoon and has initiated convective showers across the
southeast portion of the area...effecting mainly KLWS/KPUW through
04Z. Localized heavy showers may lower cigs/vsby for short
periods. In addition upsloping winds and a saturated boundary
layer will likely result in MVFR/IFR stratus overnight for
KGEG/KSFF/KCOE/KPUW through 15z. Another wet system will bring
widespread precipitation Sunday with a strong possibility for
several hours of snow at KGEG/KCOE/KSZT/KPUW...snow should turn
over to rain between 19-21z. The precipitation will bring
cig/vsby down to IFR and even LIFR at times through 00z Sunday.
/Tobin



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        30  38  28  37  32  43 /  10  90  30  10  50  60
Coeur d`Alene  30  38  29  37  33  41 /  10 100  50  20  60  80
Pullman        33  40  32  40  35  46 /  20 100  50  10  60  70
Lewiston       37  45  33  45  38  50 /  60  60  50  10  60  60
Colville       24  37  23  37  30  39 /  10  80  30  20  60  60
Sandpoint      30  36  29  37  31  39 /  20 100  50  30  70  80
Kellogg        32  35  31  35  32  38 /  50 100  70  20  70  90
Moses Lake     28  43  28  41  33  48 /  10  20  10  10  20  20
Wenatchee      33  42  32  41  35  46 /  10  40  10  10  20  30
Omak           27  37  26  37  30  41 /  10  50  10  20  30  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 6 AM PST Monday for Central
     Panhandle Mountains.

WA...None.
&&

$$





000
FXUS66 KOTX 222238
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
238 PM PST SAT NOV 22 2014

.SYNOPSIS...
Light rain and snow showers will pass through the southeast
tonight. Another round of rain and snow will arrive Sunday and
could make for slick conditions on area passes. The mountains
will receive another round of heavy snow Monday night into
Tuesday. A break in the active weather pattern will be possible
late in the week.



&&

.DISCUSSION...
Tonight and Sunday: The main focus for tonight will be an area of
showers associated with a vort max that is currently tracking
along the WA/OR border. As of 2PM, the circulation has crossed the
Cascades and clouds/radar echoes continue to blossom across the
lower Columbia Basin and north Oregon. This will not be an
extremely wet system but localized showers could be intense at
times given the cold and unstable air mass in place. Model trends
have been a bit further south placing the highest precipitation
chances south of a line from La Crosse to Avery...and current HRRR
runs suggest precipitation may struggle to expand north of
Lewiston. Gusty southerly flow ahead of this wave has resulted in
low 50s in the L-C Valley and observations from the Blues/Camas
Prairie suggest the best chance for any snow will be above 4500
feet. A secondary and even smaller wave will drop south from BC
bringing isolated snow showers across the northeast zones (NE
WA/Nrn ID) overnight. Again, these will be rather light.

So the question then becomes how much clearing will we see? This
becomes important because a wetter and more widespread
precipitation event arrives Sunday. This wave is currently visible
on afternoon Water Vapor near 140W off the WA Coast. The lift and
moisture will be much better with this wave and models are in
decent agreement of areas of east of a line from Colville to
Ritzville squeezing out between a tenth to three tenths of liquid.
Snow levels are the wildcard and ultimately comes down to how much
clearing occurs overnight. Our forecast is probably on the lower
end of the spectrum for snow levels and may need to be tweaked up
but would like to see how cold it gets tonight before doing so.
The best chance for lowland snow accumulations of 1-2 inches
will be in the NE valleys with lower amounts into the Upper
Columbia Basin and Spokane-CDA area. Elevations above 2500 feet
will carry the highest probabilities.  The eastern mountains will
receive another 2-5 inches with locally higher amounts in the
Central Panhandle Mtns and this was covered in the latest winter
weather advisory. Snow will also continue along the Cascade Crest
but taper off quickly in the lee of the Cascades where shadowing
normally occurs.

For Sunday, clouds and light precipitation will materialize
throughout the morning and intensify over the ID Panhandle and far
eastern reaches of WA (and Cascade Crest) Sunday afternoon. This
is another reason for lacking valley accumulations but mountain
passes are likely to experience snow covered roads and hazardous
travel. /sb

Sunday night through Tuesday night...Through this period of the
forecast high pressure will build in the eastern Pacific out
between 130-132W. This will keep northwest flow over the region
through Monday night then becoming west-northwest Monday night and
Tuesday. This flow pattern will allow a series of weak
disturbances to track over the ridge and drop through the forecast
area through the entire period.

Northwest flow Sunday night and Monday will keep orographic
showers across the eastern mountains...and some slop over showers
across the Cascade crest. Snow levels for the Panhandle range
from 3K feet across the south to just under 2k for the north
Panhandle. Some of the higher mountains south of I-90 could pick
up 3-4 inches of snow by Monday morning with much less for the
north Panhandle...with 1-3 inches near the Cascade crest.
Otherwise expect a dry forecast with temperatures near persistence
and near seasonal averages.

Monday night through Tuesday night the weather will move through
the region. Model guidance shows this system to have decent
moisture with PWATs going up to .85 or so. Isentropic up-glide
will increase just after 06z and quickly push across the northern
zones and finally into the eastern up-slope areas by morning.
Nothing in the way of a cold front passage will be available to
increase forcing so lift just by isentropic up-glide and
orographics. Still the models are spitting out some pretty hefty
precipitation totals. The lower east slopes and the deep basin
should get shadowed out by the Cascades but will still be able to
squeeze out a little rain.

Snow levels start out around 4K feet across the south and 2K
feet across the north but with south-southwest lower level winds
and moderate warm air advection snow levels will lift above 5k
feet across the south and above 3-3.5k feet across the north by
early Tuesday afternoon. This will result in most of the valleys
below 3k feet getting rain with snow in the mountains. 24-36 hour
snow amounts could be as high as 8-12 inches near the Cascade
crest...5-9 inches for the northeast mountains and Idaho Panhandle
mountains by Wednesday morning. A lot of these amounts will be
very dependent on just how fast the temperatures warm up during
the day Tuesday.

Tuesday will seem quite balmy with temperatures rising into the
upper 30s to lower 50s. Southwest will be on the increase again
Tuesday and Tuesday night with sustain 10-20 mph and gust 25-30
mph. /Tobin

Wednesday through Saturday...The busiest travel day of the year
will be unseasonably warm across the region as gusty southwest
winds keep the atmosphere well mixed. Temperatures will be in the
40s with low 50s possible in the southern valleys. This will keep
any precipitation in liquid form except for the high peaks. Snow
levels will start to drop as winds shift to the west during the
evening hours then become northerly overnight. Medium range models
are in general agreement on shortwave energy riding along a rather
flat ridge with the main threat of precipitation across the
northern zones on Wednesday. By Thanksgiving Day the track of the
band of moisture sinks as far south as the Palouse per the 12Z GFS
while the ECMWF keeps it more to the north. The 12Z GFS also
brings colder temps farther south with the possibility of some
light snow for the I-90 corridor. As I type this, the 18Z run of
the GFS is coming in warmer so there is quite a bit of uncertainty
as to p-type. The general trend will be cooling temperatures in
northerly flow for Friday and Friday night, then a gradual warming
as winds again shift to the southwest ahead of the next warm front
that could affect the Inland Northwest over the weekend. Warm air
moving in over the colder air entrenched at the surface could mean
the possibility of some mixed precipitation. Models disagree on
the southerly extend of the cold air at the surface and also on
the timing of this feature so for now we will keep sleet/FZRA out
of the weather grids. /Kelch

&&

.AVIATION...
18Z TAFS: The focus for this afternoon and evening will be vort
max currently moving across the Cascades which will track along
the WA/OR border. This feature is bringing less wind than previous
thought and will incr cloud cover for most terminals. Areas of
rain will impact Pullman and Lewiston and a combination of upslope
winds and moistening boundary layer will promote an incr risk for
MVFR/IFR stratus overnight. A wetter system bring more wdsprd
precip Sunday with a strong possibility for several hours of snow
at Spokane, Coeur D Alene, Sandpoint, and potentially Pullman. The
precip is likely to bring regional ceiling and vis restrictions.
/sb



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        30  38  28  37  32  43 /  10  90  30  10  50  60
Coeur d`Alene  30  38  29  37  33  41 /  10 100  50  20  60  80
Pullman        33  40  32  40  35  46 /  20 100  50  10  60  70
Lewiston       37  45  33  45  38  50 /  60  60  50  10  60  60
Colville       24  37  23  37  30  39 /  10  80  30  20  60  60
Sandpoint      30  36  29  37  31  39 /  20 100  50  30  70  80
Kellogg        32  35  31  35  32  38 /  50 100  70  20  70  90
Moses Lake     28  43  28  41  33  48 /  10  20  10  10  20  20
Wenatchee      33  42  32  41  35  46 /  10  40  10  10  20  30
Omak           27  37  26  37  30  41 /  10  50  10  20  30  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 6 AM PST Monday for Central
     Panhandle Mountains.

WA...None.
&&

$$





000
FXUS66 KOTX 222238
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
238 PM PST SAT NOV 22 2014

.SYNOPSIS...
Light rain and snow showers will pass through the southeast
tonight. Another round of rain and snow will arrive Sunday and
could make for slick conditions on area passes. The mountains
will receive another round of heavy snow Monday night into
Tuesday. A break in the active weather pattern will be possible
late in the week.



&&

.DISCUSSION...
Tonight and Sunday: The main focus for tonight will be an area of
showers associated with a vort max that is currently tracking
along the WA/OR border. As of 2PM, the circulation has crossed the
Cascades and clouds/radar echoes continue to blossom across the
lower Columbia Basin and north Oregon. This will not be an
extremely wet system but localized showers could be intense at
times given the cold and unstable air mass in place. Model trends
have been a bit further south placing the highest precipitation
chances south of a line from La Crosse to Avery...and current HRRR
runs suggest precipitation may struggle to expand north of
Lewiston. Gusty southerly flow ahead of this wave has resulted in
low 50s in the L-C Valley and observations from the Blues/Camas
Prairie suggest the best chance for any snow will be above 4500
feet. A secondary and even smaller wave will drop south from BC
bringing isolated snow showers across the northeast zones (NE
WA/Nrn ID) overnight. Again, these will be rather light.

So the question then becomes how much clearing will we see? This
becomes important because a wetter and more widespread
precipitation event arrives Sunday. This wave is currently visible
on afternoon Water Vapor near 140W off the WA Coast. The lift and
moisture will be much better with this wave and models are in
decent agreement of areas of east of a line from Colville to
Ritzville squeezing out between a tenth to three tenths of liquid.
Snow levels are the wildcard and ultimately comes down to how much
clearing occurs overnight. Our forecast is probably on the lower
end of the spectrum for snow levels and may need to be tweaked up
but would like to see how cold it gets tonight before doing so.
The best chance for lowland snow accumulations of 1-2 inches
will be in the NE valleys with lower amounts into the Upper
Columbia Basin and Spokane-CDA area. Elevations above 2500 feet
will carry the highest probabilities.  The eastern mountains will
receive another 2-5 inches with locally higher amounts in the
Central Panhandle Mtns and this was covered in the latest winter
weather advisory. Snow will also continue along the Cascade Crest
but taper off quickly in the lee of the Cascades where shadowing
normally occurs.

For Sunday, clouds and light precipitation will materialize
throughout the morning and intensify over the ID Panhandle and far
eastern reaches of WA (and Cascade Crest) Sunday afternoon. This
is another reason for lacking valley accumulations but mountain
passes are likely to experience snow covered roads and hazardous
travel. /sb

Sunday night through Tuesday night...Through this period of the
forecast high pressure will build in the eastern Pacific out
between 130-132W. This will keep northwest flow over the region
through Monday night then becoming west-northwest Monday night and
Tuesday. This flow pattern will allow a series of weak
disturbances to track over the ridge and drop through the forecast
area through the entire period.

Northwest flow Sunday night and Monday will keep orographic
showers across the eastern mountains...and some slop over showers
across the Cascade crest. Snow levels for the Panhandle range
from 3K feet across the south to just under 2k for the north
Panhandle. Some of the higher mountains south of I-90 could pick
up 3-4 inches of snow by Monday morning with much less for the
north Panhandle...with 1-3 inches near the Cascade crest.
Otherwise expect a dry forecast with temperatures near persistence
and near seasonal averages.

Monday night through Tuesday night the weather will move through
the region. Model guidance shows this system to have decent
moisture with PWATs going up to .85 or so. Isentropic up-glide
will increase just after 06z and quickly push across the northern
zones and finally into the eastern up-slope areas by morning.
Nothing in the way of a cold front passage will be available to
increase forcing so lift just by isentropic up-glide and
orographics. Still the models are spitting out some pretty hefty
precipitation totals. The lower east slopes and the deep basin
should get shadowed out by the Cascades but will still be able to
squeeze out a little rain.

Snow levels start out around 4K feet across the south and 2K
feet across the north but with south-southwest lower level winds
and moderate warm air advection snow levels will lift above 5k
feet across the south and above 3-3.5k feet across the north by
early Tuesday afternoon. This will result in most of the valleys
below 3k feet getting rain with snow in the mountains. 24-36 hour
snow amounts could be as high as 8-12 inches near the Cascade
crest...5-9 inches for the northeast mountains and Idaho Panhandle
mountains by Wednesday morning. A lot of these amounts will be
very dependent on just how fast the temperatures warm up during
the day Tuesday.

Tuesday will seem quite balmy with temperatures rising into the
upper 30s to lower 50s. Southwest will be on the increase again
Tuesday and Tuesday night with sustain 10-20 mph and gust 25-30
mph. /Tobin

Wednesday through Saturday...The busiest travel day of the year
will be unseasonably warm across the region as gusty southwest
winds keep the atmosphere well mixed. Temperatures will be in the
40s with low 50s possible in the southern valleys. This will keep
any precipitation in liquid form except for the high peaks. Snow
levels will start to drop as winds shift to the west during the
evening hours then become northerly overnight. Medium range models
are in general agreement on shortwave energy riding along a rather
flat ridge with the main threat of precipitation across the
northern zones on Wednesday. By Thanksgiving Day the track of the
band of moisture sinks as far south as the Palouse per the 12Z GFS
while the ECMWF keeps it more to the north. The 12Z GFS also
brings colder temps farther south with the possibility of some
light snow for the I-90 corridor. As I type this, the 18Z run of
the GFS is coming in warmer so there is quite a bit of uncertainty
as to p-type. The general trend will be cooling temperatures in
northerly flow for Friday and Friday night, then a gradual warming
as winds again shift to the southwest ahead of the next warm front
that could affect the Inland Northwest over the weekend. Warm air
moving in over the colder air entrenched at the surface could mean
the possibility of some mixed precipitation. Models disagree on
the southerly extend of the cold air at the surface and also on
the timing of this feature so for now we will keep sleet/FZRA out
of the weather grids. /Kelch

&&

.AVIATION...
18Z TAFS: The focus for this afternoon and evening will be vort
max currently moving across the Cascades which will track along
the WA/OR border. This feature is bringing less wind than previous
thought and will incr cloud cover for most terminals. Areas of
rain will impact Pullman and Lewiston and a combination of upslope
winds and moistening boundary layer will promote an incr risk for
MVFR/IFR stratus overnight. A wetter system bring more wdsprd
precip Sunday with a strong possibility for several hours of snow
at Spokane, Coeur D Alene, Sandpoint, and potentially Pullman. The
precip is likely to bring regional ceiling and vis restrictions.
/sb



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        30  38  28  37  32  43 /  10  90  30  10  50  60
Coeur d`Alene  30  38  29  37  33  41 /  10 100  50  20  60  80
Pullman        33  40  32  40  35  46 /  20 100  50  10  60  70
Lewiston       37  45  33  45  38  50 /  60  60  50  10  60  60
Colville       24  37  23  37  30  39 /  10  80  30  20  60  60
Sandpoint      30  36  29  37  31  39 /  20 100  50  30  70  80
Kellogg        32  35  31  35  32  38 /  50 100  70  20  70  90
Moses Lake     28  43  28  41  33  48 /  10  20  10  10  20  20
Wenatchee      33  42  32  41  35  46 /  10  40  10  10  20  30
Omak           27  37  26  37  30  41 /  10  50  10  20  30  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 6 AM PST Monday for Central
     Panhandle Mountains.

WA...None.
&&

$$






000
FXUS66 KOTX 221808
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1008 AM PST SAT NOV 22 2014

.SYNOPSIS...
Today will be windy over most of the Inland Northwest. Snow
showers will persist over the Cascades and mountains of the Idaho
Panhandle. Another round of rain and wet snow is expected on
Sunday. The mountains will receive another round of heavy snow
Monday night into Tuesday. A break in the active weather pattern
will be possible Wednesday through Friday.


&&

.DISCUSSION...
Morning update: We have downgraded the winter storm warning for
the Central Idaho Panhandle Mtns to a winter weather advisory.
Drier air aloft has temporarily moved into the region and any
snow shower activity this afternoon will be light and not amount
to much.

This will change this evening as a second wave comes through the
region...re-moistening the dendritic layer...and increasing lift.
This wave is currently moving into Wrn MT and clouds are already
thickening east of the Cascades...a sign of the lift. Look for
light precipitation to accompany this wave across the lower Basin
this afternoon then into the lower ID panhandle this evening. This
will bring an additional 1-2 inches of snowfall into the Central
Panhandle Mtns with the biggest uncertainty whether it will remain
just over southern Shoshone County (south of I-90) or expand
northward toward the interstate. Several inches of snow will also
fall in the Blue Mtns and Camas Prairie mainly at or above 4000`.

Further west, we will see very little break in snow shower
activity along the Cascade Crest which at times will slop over
into Central and perhaps eastern Chelan County, especially where
narrow convergent bands setup.

Winds are having a hard time mixing down the surface in the
immediate lee of the Cascades so did adjust temperatures down some
for locations like Omak and Oroville.

A wetter storm system will bring more widespread precipitation
Sunday. This will lead to more wintry travel across the ID/MT
passes along with more localized wintry travel through the Cascade
Passes. More details to follow this afternoon. /sb




&&

.AVIATION...
18Z TAFS: The focus for this afternoon and evening will be vort
max currently moving across the Cascades which will track along
the WA/OR border. This feature is bringing less wind than previous
thought and will incr cloud cover for most terminals. Areas of
rain will impact Pullman and Lewiston and a combination of upslope
winds and moistening boundary layer will promote an incr risk for
MVFR/IFR stratus overnight. A wetter system bring more wdsprd
precip Sunday with a strong possibility for several hours of snow
at Spokane, Coeur D Alene, Sandpoint, and potentially Pullman. The
precip is likely to bring regional ceiling and vis restrictions.
/sb


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        42  30  38  29  37  30 /  10  10  70  30  10  40
Coeur d`Alene  42  30  38  29  37  31 /  20  20  80  50  20  50
Pullman        45  33  40  32  40  33 /  20  50  80  50  10  30
Lewiston       50  36  45  33  44  36 /  40  40  50  50  10  20
Colville       41  24  37  24  37  28 /  10  10  70  30  20  60
Sandpoint      40  29  36  29  37  30 /  20  20  90  50  30  70
Kellogg        41  31  35  31  35  30 /  20  60 100  70  30  60
Moses Lake     45  29  43  30  42  31 /  20  10  30  10  10  20
Wenatchee      45  32  42  32  42  33 /  10  10  30  10  10  20
Omak           38  27  37  26  37  28 /  10  10  40  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 6 AM PST Monday for Central
     Panhandle Mountains.

WA...None.
&&

$$





000
FXUS66 KOTX 221808
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1008 AM PST SAT NOV 22 2014

.SYNOPSIS...
Today will be windy over most of the Inland Northwest. Snow
showers will persist over the Cascades and mountains of the Idaho
Panhandle. Another round of rain and wet snow is expected on
Sunday. The mountains will receive another round of heavy snow
Monday night into Tuesday. A break in the active weather pattern
will be possible Wednesday through Friday.


&&

.DISCUSSION...
Morning update: We have downgraded the winter storm warning for
the Central Idaho Panhandle Mtns to a winter weather advisory.
Drier air aloft has temporarily moved into the region and any
snow shower activity this afternoon will be light and not amount
to much.

This will change this evening as a second wave comes through the
region...re-moistening the dendritic layer...and increasing lift.
This wave is currently moving into Wrn MT and clouds are already
thickening east of the Cascades...a sign of the lift. Look for
light precipitation to accompany this wave across the lower Basin
this afternoon then into the lower ID panhandle this evening. This
will bring an additional 1-2 inches of snowfall into the Central
Panhandle Mtns with the biggest uncertainty whether it will remain
just over southern Shoshone County (south of I-90) or expand
northward toward the interstate. Several inches of snow will also
fall in the Blue Mtns and Camas Prairie mainly at or above 4000`.

Further west, we will see very little break in snow shower
activity along the Cascade Crest which at times will slop over
into Central and perhaps eastern Chelan County, especially where
narrow convergent bands setup.

Winds are having a hard time mixing down the surface in the
immediate lee of the Cascades so did adjust temperatures down some
for locations like Omak and Oroville.

A wetter storm system will bring more widespread precipitation
Sunday. This will lead to more wintry travel across the ID/MT
passes along with more localized wintry travel through the Cascade
Passes. More details to follow this afternoon. /sb




&&

.AVIATION...
18Z TAFS: The focus for this afternoon and evening will be vort
max currently moving across the Cascades which will track along
the WA/OR border. This feature is bringing less wind than previous
thought and will incr cloud cover for most terminals. Areas of
rain will impact Pullman and Lewiston and a combination of upslope
winds and moistening boundary layer will promote an incr risk for
MVFR/IFR stratus overnight. A wetter system bring more wdsprd
precip Sunday with a strong possibility for several hours of snow
at Spokane, Coeur D Alene, Sandpoint, and potentially Pullman. The
precip is likely to bring regional ceiling and vis restrictions.
/sb


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        42  30  38  29  37  30 /  10  10  70  30  10  40
Coeur d`Alene  42  30  38  29  37  31 /  20  20  80  50  20  50
Pullman        45  33  40  32  40  33 /  20  50  80  50  10  30
Lewiston       50  36  45  33  44  36 /  40  40  50  50  10  20
Colville       41  24  37  24  37  28 /  10  10  70  30  20  60
Sandpoint      40  29  36  29  37  30 /  20  20  90  50  30  70
Kellogg        41  31  35  31  35  30 /  20  60 100  70  30  60
Moses Lake     45  29  43  30  42  31 /  20  10  30  10  10  20
Wenatchee      45  32  42  32  42  33 /  10  10  30  10  10  20
Omak           38  27  37  26  37  28 /  10  10  40  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 6 AM PST Monday for Central
     Panhandle Mountains.

WA...None.
&&

$$






000
FXUS66 KOTX 221226
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
426 AM PST SAT NOV 22 2014

.SYNOPSIS...
Today will be windy over most of the Inland Northwest. Snow
showers will persist over the Cascades and moutains of the Idaho
Panhandle. Another round of rain and wet snow is expected on
Sunday. The mountains will receive another round of heavy snow
Monday night into Tuesday. A break in the active weather pattern
will be possible Wednesday through Friday.

&&

.DISCUSSION...

Today and Tonight: Heavy mountain snow accumulations will continue
early this morning over the Central Idaho Panhandle. As of 230 AM,
the cold front associated with a moist early winter storm was
moving through western Montana and the Idaho Panhandle. The NAM
suggests that there may be a decrease in the snow during the mid
to late morning hours as the front moves east, but post-frontal
convective snow showers will likely redevelop by afternoon as the
500mb cold pool moves over the Panhandle. Deep instability
combined with mid-level northwest flow will produce a resurgence
of orographic snow showers over southern Shoshone county, the
Blue Mountains, and perhaps the higher elevations of the Camas
Prairie. Current radar trends suggest that we may be able to
discontinue the Winter Storm Warning for the mountains around
Sandpoint and Bonners Ferry. Post-frontal, northwest flow patterns
aren`t particularly favorable the the mountains of the north Idaho
Panhandle, and radar trends suggest that snow has already begun to
decrease. With the exception of a Puget Sound Convergence zone in
the vicinity of Stevens Pass, snow showers have diminished
significantly over the north Washington Cascades. We should be
able to let the Winter Storm Warning for this zone expire as
scheduled at 6 AM.

Elsewhere today, gusty west winds (sustained 15 to 20 mph with
gusts to 35 mph) will produce enough mixing to push temperatures
into the upper 30s to mid 40s in most places. Despite the warming
in the low elevations, snow levels will fall this morning
following the passage of our cold front. Our recent stagnant
pattern has been broken and our low level inversion scrubbed away.

Sunday and Sunday Night: A fast moving low pressure system will
follow quickly on the heals of our current winter storm. This low
is evident on satellite south of Alaska. Look for a shield of
precipitation to develop during the late morning hours on Sunday
as strong warm/moist advection occurs along a warm front. Snow
levels will initially be be down to the valley floors Sunday
morning, but will rise quickly as south winds increase through the
day Sunday. Wet accumulations of 1 to 2 inches will be possible
Sunday in places like Davenport, Colville, Republic, Sandpoint and
Bonners Ferry. At this time, Sunday`s system does not look like it
will have much impact on travel. Most of the wet snow will fall
during the late morning into the afternoon. That should limit
accumulations on the roads with the exception of elevations above
3500 feet like Fourth of July Pass, Lookout Pass, Sherman Pass and
the high passes in the Cascades. /GKoch


Monday through Wednesday night...Narrow long-wave ridging starts
to amplify off the coast during this time interval in similar
fashion to what occurred last week. This change will alter the
track of incoming storms starting as early as Monday as moisture
streaming overtop the ridge with its low amplitude and axis
placement off the coast allows for a continuation of pops that
peak on Monday. There is no cold air at lower levels to overrun
and as the moisture plume streaming into the ridge sags south the
lowlands in the lee of the cascades will have some lower pops due
to expected rain/snow shadow development but locations further to
the north and east have a better chance of maintaining lift and
therefore keep higher pops and qpf amounts. Pops peak again
Tuesday as disturbances drop down in the northwest flow to the
east of the offshore ridge axis and enhance lifting along the
baroclinic band/moisture plume still remaining over Eastern
Washington and North Idaho. The expectation is the ridging in the
region will amplify and push the baroclinic band back to the north
and northeast. By pushing the baroclinic band further away from
the forecast area pops show a decrease Tuesday into most of
Tuesday night. Models solutions diverge in important ways
Wednesday into Wednesday night with the favored ECMWF amplifying
the ridge yet keeping the axis placed in closer proximity to the
Cascades which results in a drier, yet still cloudy Wednesday and
Wednesday night with any pops limited to northern locations not
too far from the Southern British Columbia border. The less
favored GFS positions the narrow ridge further west and off the
coast which favors the possibility of cool Canadian air dropping
down from the north resulting in a cool down with brisk northerly
winds. At this time will follow the ECMWF solution with ridge
placement closer to the Cascades which keep the Wednesday and
Wednesday night forecast simpler with moderate cloud cover yet
minimal pops and the overall gradual warming trend continuing.
/Pelatti

&&

.AVIATION...
12Z TAFS: Strong post cold front mixing has scrubbed out most of
the low stratus in eastern Washington this morning. Some low
clouds remain in the upslope regions of the north Idaho Panhadle
like Sandpoint and Kellogg. Winds will become quite gusty at
Spokane, Pullman, and Lewiston by mid morning with gusts up to
30kts through late afternoon. Orographic snow showers will obscure
the mountains of the Idaho Panhandle and the Cascade Crest today
and tonight. /GKoch


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        41  30  38  29  37  30 /  10  10  70  30  20  40
Coeur d`Alene  40  31  38  29  37  31 /  30  20  80  50  30  50
Pullman        43  34  40  32  40  33 /  40  50  80  50  20  30
Lewiston       47  37  45  33  44  36 /  40  40  50  50  20  20
Colville       42  24  37  24  37  28 /  10  10  70  30  30  60
Sandpoint      40  30  36  29  37  30 /  30  20  90  50  30  70
Kellogg        38  31  35  31  35  30 /  60  60 100  70  30  60
Moses Lake     46  28  43  30  42  31 /  10  10  30  10  20  20
Wenatchee      43  33  42  32  42  33 /  20  10  30  10  20  20
Omak           41  27  37  26  37  28 /  10  10  40  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST this evening for Northern
     Panhandle.

WA...Winter Storm Warning until 6 AM PST early this morning for East
     Slopes Northern Cascades.

&&

$$





000
FXUS66 KOTX 221226
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
426 AM PST SAT NOV 22 2014

.SYNOPSIS...
Today will be windy over most of the Inland Northwest. Snow
showers will persist over the Cascades and moutains of the Idaho
Panhandle. Another round of rain and wet snow is expected on
Sunday. The mountains will receive another round of heavy snow
Monday night into Tuesday. A break in the active weather pattern
will be possible Wednesday through Friday.

&&

.DISCUSSION...

Today and Tonight: Heavy mountain snow accumulations will continue
early this morning over the Central Idaho Panhandle. As of 230 AM,
the cold front associated with a moist early winter storm was
moving through western Montana and the Idaho Panhandle. The NAM
suggests that there may be a decrease in the snow during the mid
to late morning hours as the front moves east, but post-frontal
convective snow showers will likely redevelop by afternoon as the
500mb cold pool moves over the Panhandle. Deep instability
combined with mid-level northwest flow will produce a resurgence
of orographic snow showers over southern Shoshone county, the
Blue Mountains, and perhaps the higher elevations of the Camas
Prairie. Current radar trends suggest that we may be able to
discontinue the Winter Storm Warning for the mountains around
Sandpoint and Bonners Ferry. Post-frontal, northwest flow patterns
aren`t particularly favorable the the mountains of the north Idaho
Panhandle, and radar trends suggest that snow has already begun to
decrease. With the exception of a Puget Sound Convergence zone in
the vicinity of Stevens Pass, snow showers have diminished
significantly over the north Washington Cascades. We should be
able to let the Winter Storm Warning for this zone expire as
scheduled at 6 AM.

Elsewhere today, gusty west winds (sustained 15 to 20 mph with
gusts to 35 mph) will produce enough mixing to push temperatures
into the upper 30s to mid 40s in most places. Despite the warming
in the low elevations, snow levels will fall this morning
following the passage of our cold front. Our recent stagnant
pattern has been broken and our low level inversion scrubbed away.

Sunday and Sunday Night: A fast moving low pressure system will
follow quickly on the heals of our current winter storm. This low
is evident on satellite south of Alaska. Look for a shield of
precipitation to develop during the late morning hours on Sunday
as strong warm/moist advection occurs along a warm front. Snow
levels will initially be be down to the valley floors Sunday
morning, but will rise quickly as south winds increase through the
day Sunday. Wet accumulations of 1 to 2 inches will be possible
Sunday in places like Davenport, Colville, Republic, Sandpoint and
Bonners Ferry. At this time, Sunday`s system does not look like it
will have much impact on travel. Most of the wet snow will fall
during the late morning into the afternoon. That should limit
accumulations on the roads with the exception of elevations above
3500 feet like Fourth of July Pass, Lookout Pass, Sherman Pass and
the high passes in the Cascades. /GKoch


Monday through Wednesday night...Narrow long-wave ridging starts
to amplify off the coast during this time interval in similar
fashion to what occurred last week. This change will alter the
track of incoming storms starting as early as Monday as moisture
streaming overtop the ridge with its low amplitude and axis
placement off the coast allows for a continuation of pops that
peak on Monday. There is no cold air at lower levels to overrun
and as the moisture plume streaming into the ridge sags south the
lowlands in the lee of the cascades will have some lower pops due
to expected rain/snow shadow development but locations further to
the north and east have a better chance of maintaining lift and
therefore keep higher pops and qpf amounts. Pops peak again
Tuesday as disturbances drop down in the northwest flow to the
east of the offshore ridge axis and enhance lifting along the
baroclinic band/moisture plume still remaining over Eastern
Washington and North Idaho. The expectation is the ridging in the
region will amplify and push the baroclinic band back to the north
and northeast. By pushing the baroclinic band further away from
the forecast area pops show a decrease Tuesday into most of
Tuesday night. Models solutions diverge in important ways
Wednesday into Wednesday night with the favored ECMWF amplifying
the ridge yet keeping the axis placed in closer proximity to the
Cascades which results in a drier, yet still cloudy Wednesday and
Wednesday night with any pops limited to northern locations not
too far from the Southern British Columbia border. The less
favored GFS positions the narrow ridge further west and off the
coast which favors the possibility of cool Canadian air dropping
down from the north resulting in a cool down with brisk northerly
winds. At this time will follow the ECMWF solution with ridge
placement closer to the Cascades which keep the Wednesday and
Wednesday night forecast simpler with moderate cloud cover yet
minimal pops and the overall gradual warming trend continuing.
/Pelatti

&&

.AVIATION...
12Z TAFS: Strong post cold front mixing has scrubbed out most of
the low stratus in eastern Washington this morning. Some low
clouds remain in the upslope regions of the north Idaho Panhadle
like Sandpoint and Kellogg. Winds will become quite gusty at
Spokane, Pullman, and Lewiston by mid morning with gusts up to
30kts through late afternoon. Orographic snow showers will obscure
the mountains of the Idaho Panhandle and the Cascade Crest today
and tonight. /GKoch


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        41  30  38  29  37  30 /  10  10  70  30  20  40
Coeur d`Alene  40  31  38  29  37  31 /  30  20  80  50  30  50
Pullman        43  34  40  32  40  33 /  40  50  80  50  20  30
Lewiston       47  37  45  33  44  36 /  40  40  50  50  20  20
Colville       42  24  37  24  37  28 /  10  10  70  30  30  60
Sandpoint      40  30  36  29  37  30 /  30  20  90  50  30  70
Kellogg        38  31  35  31  35  30 /  60  60 100  70  30  60
Moses Lake     46  28  43  30  42  31 /  10  10  30  10  20  20
Wenatchee      43  33  42  32  42  33 /  20  10  30  10  20  20
Omak           41  27  37  26  37  28 /  10  10  40  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST this evening for Northern
     Panhandle.

WA...Winter Storm Warning until 6 AM PST early this morning for East
     Slopes Northern Cascades.

&&

$$






000
FXUS66 KOTX 221055
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
255 AM PST SAT NOV 22 2014

.SYNOPSIS...
Today will be windy over most of the Inland Northwest. Snow
showers will persist over the Cascades and mountains of the Idaho
Panhandle. Another round of rain and wet snow is expected on
Sunday. The mountains will receive another round of heavy snow
Monday night into Tuesday. A break in the active weather pattern
will be possible Wednesday through Friday.

&&

.DISCUSSION...

Today and Tonight: Heavy mountain snow accumulations will continue
early this morning over the Central Idaho Panhandle. As of 230 AM,
the cold front associated with a moist early winter storm was
moving through western Montana and the Idaho Panhandle. The NAM
suggests that there may be a decrease in the snow during the mid
to late morning hours as the front moves east, but post-frontal
convective snow showers will likely redevelop by afternoon as the
500mb cold pool moves over the Panhandle. Deep instability
combined with mid-level northwest flow will produce a resurgence
of orographic snow showers over southern Shoshone county, the
Blue Mountains, and perhaps the higher elevations of the Camas
Prairie. Current radar trends suggest that we may be able to
discontinue the Winter Storm Warning for the mountains around
Sandpoint and Bonners Ferry. Post-frontal, northwest flow patterns
aren`t particularly favorable the the mountains of the north Idaho
Panhandle, and radar trends suggest that snow has already begun to
decrease. With the exception of a Puget Sound Convergence zone in
the vicinity of Stevens Pass, snow showers have diminished
significantly over the north Washington Cascades. We should be
able to let the Winter Storm Warning for this zone expire as
scheduled at 6 AM.

Elsewhere today, gusty west winds (sustained 15 to 20 mph with
gusts to 35 mph) will produce enough mixing to push temperatures
into the upper 30s to mid 40s in most places. Despite the warming
in the low elevations, snow levels will fall this morning
following the passage of our cold front. Our recent stagnant
pattern has been broken and our low level inversion scrubbed away.

Sunday and Sunday Night: A fast moving low pressure system will
follow quickly on the heals of our current winter storm. This low
is evident on satellite south of Alaska. Look for a shield of
precipitation to develop during the late MORNING hours on Sunday
as strong warm/moist advection occurs along a warm front. Snow
levels will initially be be down to the valley floors Sunday
morning, but will rise quickly as south winds increase through the
day Sunday. Wet accumulations of 1 to 2 inches will be possible
Sunday in places like Davenport, Colville, Republic, Sandpoint and
Bonners Ferry. At this time, Sunday`s system does not look like it
will have much impact on travel. Most of the wet snow will fall
during the late morning into the afternoon. That should limit
accumulations on the roads with the exception of elevations above
3500 feet like Fourth of July Pass, Lookout Pass, Sherman Pass and
the high passes in the Cascades. /GKoch


Monday through Wednesday night...Narrow long-wave ridging starts
to amplify off the coast during this time interval in similar
fashion to what occurred last week. This change will alter the
track of incoming storms starting as early as Monday as moisture
streaming overtop the ridge with its low amplitude and axis
placement off the coast allows for a continuation of pops that
peak on Monday. There is no cold air at lower levels to overrun
and as the moisture plume streaming into the ridge sags south the
lowlands in the lee of the cascades will have some lower pops due
to expected rain/snow shadow development but locations further to
the north and east have a better chance of maintaining lift and
therefore keep higher pops and qpf amounts. Pops peak again
Tuesday as disturbances drop down in the northwest flow to the
east of the offshore ridge axis and enhance lifting along the
baroclinic band/moisture plume still remaining over Eastern
Washington and North Idaho. The expectation is the ridging in the
region will amplify and push the baroclinic band back to the north
and northeast. By pushing the baroclinic band further away from
the forecast area pops show a decrease Tuesday into most of
Tuesday night. Models solutions diverge in important ways
Wednesday into Wednesday night with the favored ECMWF amplifying
the ridge yet keeping the axis placed in closer proximity to the
Cascades which results in a drier, yet still cloudy Wednesday and
Wednesday night with any pops limited to northern locations not
too far from the Southern British Columbia border. The less
favored GFS positions the narrow ridge further west and off the
coast which favors the possibility of cool Canadian air dropping
down from the north resulting in a cool down with brisk northerly
winds. At this time will follow the ECMWF solution with ridge
placement closer to the Cascades which keep the Wednesday and
Wednesday night forecast simpler with moderate cloud cover yet
minimal pops and the overall gradual warming trend continuing.
/Pelatti


Thanksgiving through Saturday: The extended forecast continues to
be riddled with uncertainties as the 00Z GFS and 00Z ECMWF paint
two very different pictures for the end of the week. After being
in decent agreement with the 12Z runs earlier, they have have now
lost all of that and once again have little they agree upon. For
this forecast I went with the more consistent picture from earlier
with a ridge over the region Thursday morning keeping the majority
of the lowlands dry for the holiday with mild temperatures. This
solution was depicted by both the 12Z and 00Z Euro along with the
12Z and 18Z GFS. Then came the 00Z and 06Z GFS runs which once
again showed the cold polar air dropping in from BC similarly to
what it had last night. Even with the GFS, it would lead to a
likely dry turkey day, but with significantly cooler conditions.
Going with the Euro would bring another Pacific system into the
region Friday with valley and mid slope rain and only snow in the
higher elevations. The newest Euro would bring wet and mild conditions
for both Friday and Saturday while the GFS would just be cool and
dry with the majority of the moisture diving south. While I
discounted the newest GFS due to inconsistencies for this
forecast, it and the overall trending of models will have to be
further examined as we approach this time frame to pin down the
details. /Fliehman

&&

.AVIATION...
06Z TAFS: Snow has winded down in the lee of the Cascades with the
passage of a cold front. It will take some time to break the low-
level inversions and completely scrub out the moist boundary layer
conditions and this will promote low-level wind shear for a few
hours. Once southwest winds mix to the surface, llws will end and
gusty winds will deliver improving VIS and CIG. -shsn will
continue along the Cascade Crest and mountains of ID through much
of Saturday continuing to bring mtn obscrns. A second wave looks
to renew a threat for showers across SE WA and Nrn ID aft 22z. /sb




&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        41  30  38  29  37  30 /  10  10  70  30  20  40
Coeur d`Alene  40  31  38  29  37  31 /  30  20  80  50  30  50
Pullman        43  34  40  32  40  33 /  40  50  80  50  20  30
Lewiston       47  37  45  33  44  36 /  40  40  50  50  20  20
Colville       42  24  37  24  37  28 /  10  10  70  30  30  60
Sandpoint      40  30  36  29  37  30 /  30  20  90  50  30  70
Kellogg        38  31  35  31  35  30 /  60  60 100  70  30  60
Moses Lake     46  28  43  30  42  31 /  10  10  30  10  20  20
Wenatchee      43  33  42  32  42  33 /  20  10  30  10  20  20
Omak           41  27  37  26  37  28 /  10  10  40  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST this evening for Northern
     Panhandle.

WA...Winter Storm Warning until 6 AM PST early this morning for East
     Slopes Northern Cascades.

&&

$$






000
FXUS66 KOTX 221055
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
255 AM PST SAT NOV 22 2014

.SYNOPSIS...
Today will be windy over most of the Inland Northwest. Snow
showers will persist over the Cascades and mountains of the Idaho
Panhandle. Another round of rain and wet snow is expected on
Sunday. The mountains will receive another round of heavy snow
Monday night into Tuesday. A break in the active weather pattern
will be possible Wednesday through Friday.

&&

.DISCUSSION...

Today and Tonight: Heavy mountain snow accumulations will continue
early this morning over the Central Idaho Panhandle. As of 230 AM,
the cold front associated with a moist early winter storm was
moving through western Montana and the Idaho Panhandle. The NAM
suggests that there may be a decrease in the snow during the mid
to late morning hours as the front moves east, but post-frontal
convective snow showers will likely redevelop by afternoon as the
500mb cold pool moves over the Panhandle. Deep instability
combined with mid-level northwest flow will produce a resurgence
of orographic snow showers over southern Shoshone county, the
Blue Mountains, and perhaps the higher elevations of the Camas
Prairie. Current radar trends suggest that we may be able to
discontinue the Winter Storm Warning for the mountains around
Sandpoint and Bonners Ferry. Post-frontal, northwest flow patterns
aren`t particularly favorable the the mountains of the north Idaho
Panhandle, and radar trends suggest that snow has already begun to
decrease. With the exception of a Puget Sound Convergence zone in
the vicinity of Stevens Pass, snow showers have diminished
significantly over the north Washington Cascades. We should be
able to let the Winter Storm Warning for this zone expire as
scheduled at 6 AM.

Elsewhere today, gusty west winds (sustained 15 to 20 mph with
gusts to 35 mph) will produce enough mixing to push temperatures
into the upper 30s to mid 40s in most places. Despite the warming
in the low elevations, snow levels will fall this morning
following the passage of our cold front. Our recent stagnant
pattern has been broken and our low level inversion scrubbed away.

Sunday and Sunday Night: A fast moving low pressure system will
follow quickly on the heals of our current winter storm. This low
is evident on satellite south of Alaska. Look for a shield of
precipitation to develop during the late MORNING hours on Sunday
as strong warm/moist advection occurs along a warm front. Snow
levels will initially be be down to the valley floors Sunday
morning, but will rise quickly as south winds increase through the
day Sunday. Wet accumulations of 1 to 2 inches will be possible
Sunday in places like Davenport, Colville, Republic, Sandpoint and
Bonners Ferry. At this time, Sunday`s system does not look like it
will have much impact on travel. Most of the wet snow will fall
during the late morning into the afternoon. That should limit
accumulations on the roads with the exception of elevations above
3500 feet like Fourth of July Pass, Lookout Pass, Sherman Pass and
the high passes in the Cascades. /GKoch


Monday through Wednesday night...Narrow long-wave ridging starts
to amplify off the coast during this time interval in similar
fashion to what occurred last week. This change will alter the
track of incoming storms starting as early as Monday as moisture
streaming overtop the ridge with its low amplitude and axis
placement off the coast allows for a continuation of pops that
peak on Monday. There is no cold air at lower levels to overrun
and as the moisture plume streaming into the ridge sags south the
lowlands in the lee of the cascades will have some lower pops due
to expected rain/snow shadow development but locations further to
the north and east have a better chance of maintaining lift and
therefore keep higher pops and qpf amounts. Pops peak again
Tuesday as disturbances drop down in the northwest flow to the
east of the offshore ridge axis and enhance lifting along the
baroclinic band/moisture plume still remaining over Eastern
Washington and North Idaho. The expectation is the ridging in the
region will amplify and push the baroclinic band back to the north
and northeast. By pushing the baroclinic band further away from
the forecast area pops show a decrease Tuesday into most of
Tuesday night. Models solutions diverge in important ways
Wednesday into Wednesday night with the favored ECMWF amplifying
the ridge yet keeping the axis placed in closer proximity to the
Cascades which results in a drier, yet still cloudy Wednesday and
Wednesday night with any pops limited to northern locations not
too far from the Southern British Columbia border. The less
favored GFS positions the narrow ridge further west and off the
coast which favors the possibility of cool Canadian air dropping
down from the north resulting in a cool down with brisk northerly
winds. At this time will follow the ECMWF solution with ridge
placement closer to the Cascades which keep the Wednesday and
Wednesday night forecast simpler with moderate cloud cover yet
minimal pops and the overall gradual warming trend continuing.
/Pelatti


Thanksgiving through Saturday: The extended forecast continues to
be riddled with uncertainties as the 00Z GFS and 00Z ECMWF paint
two very different pictures for the end of the week. After being
in decent agreement with the 12Z runs earlier, they have have now
lost all of that and once again have little they agree upon. For
this forecast I went with the more consistent picture from earlier
with a ridge over the region Thursday morning keeping the majority
of the lowlands dry for the holiday with mild temperatures. This
solution was depicted by both the 12Z and 00Z Euro along with the
12Z and 18Z GFS. Then came the 00Z and 06Z GFS runs which once
again showed the cold polar air dropping in from BC similarly to
what it had last night. Even with the GFS, it would lead to a
likely dry turkey day, but with significantly cooler conditions.
Going with the Euro would bring another Pacific system into the
region Friday with valley and mid slope rain and only snow in the
higher elevations. The newest Euro would bring wet and mild conditions
for both Friday and Saturday while the GFS would just be cool and
dry with the majority of the moisture diving south. While I
discounted the newest GFS due to inconsistencies for this
forecast, it and the overall trending of models will have to be
further examined as we approach this time frame to pin down the
details. /Fliehman

&&

.AVIATION...
06Z TAFS: Snow has winded down in the lee of the Cascades with the
passage of a cold front. It will take some time to break the low-
level inversions and completely scrub out the moist boundary layer
conditions and this will promote low-level wind shear for a few
hours. Once southwest winds mix to the surface, llws will end and
gusty winds will deliver improving VIS and CIG. -shsn will
continue along the Cascade Crest and mountains of ID through much
of Saturday continuing to bring mtn obscrns. A second wave looks
to renew a threat for showers across SE WA and Nrn ID aft 22z. /sb




&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        41  30  38  29  37  30 /  10  10  70  30  20  40
Coeur d`Alene  40  31  38  29  37  31 /  30  20  80  50  30  50
Pullman        43  34  40  32  40  33 /  40  50  80  50  20  30
Lewiston       47  37  45  33  44  36 /  40  40  50  50  20  20
Colville       42  24  37  24  37  28 /  10  10  70  30  30  60
Sandpoint      40  30  36  29  37  30 /  30  20  90  50  30  70
Kellogg        38  31  35  31  35  30 /  60  60 100  70  30  60
Moses Lake     46  28  43  30  42  31 /  10  10  30  10  20  20
Wenatchee      43  33  42  32  42  33 /  20  10  30  10  20  20
Omak           41  27  37  26  37  28 /  10  10  40  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST this evening for Northern
     Panhandle.

WA...Winter Storm Warning until 6 AM PST early this morning for East
     Slopes Northern Cascades.

&&

$$





000
FXUS66 KOTX 220636
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1036 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest. Windy conditions with mountain
snow showers are expected on Saturday and Sunday. An active and
somewhat wet weather regime will continue into the first half of
next week.



&&

.DISCUSSION...
The cold front has passed through the East Slopes and the threat
for heavy snow has ended in the lee of the Cascades. We got some
impressive snowfall totals from a few locations including 6" near
Oroville, 7" in Leavenworth, 6" just outside Malott, and 4" in
Waterville to name a few. Anyway, the cooler and unstable air mass
behind the front coupled with strong westerly winds will end the
threat for heavy snow in the lee of the Cascades and we have
cancelled the winter weather highlights early. We will leave the
highlights along the East Slopes dealing with unstable heavy snow
showers along the crest and some slop over into the upper
valleys. The most intense bands will come from a Puget Sound
Convergence Zone which is starting to set as of 1030PM and HRRR
suggest it will sag south through Chelan County
overnight...potentially reaching to the Hwy 97 corridor (at least
some lighter activity).

Steady precipitation is currently moving through far Ern WA and
the Idaho Panhandle. Snow levels are near 4500` but will be coming
down as the cooler air moves east. This will also transition pcpn
more showery but continue to bring moderate to heavy mountain snow
accumulations. The basin will continue to dry out with the most
persistent lowland showers across SE WA.

&&

.AVIATION...
06Z TAFS: Snow has winded down in the lee of the Cascades with the
passage of a cold front. It will take some time to break the low-
level inversions and completely scrub out the moist boundary layer
conditions and this will promote low-level wind shear for a few
hours. Once southwest winds mix to the surface, llws will end and
gusty winds will deliver improving VIS and CIG. -shsn will
continue along the Cascade Crest and mountains of ID through much
of Saturday continuing to bring mtn obscrns. A second wave looks
to renew a threat for showers across SE WA and Nrn ID aft 22z. /sb



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        33  41  30  38  29  37 /  60  20  20  70  30  20
Coeur d`Alene  35  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        38  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       43  47  37  45  33  44 / 100  70  40  80  50  20
Colville       32  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      32  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        34  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     31  46  28  43  30  42 /  20  10  10  30  10  20
Wenatchee      33  43  33  42  32  42 /  20  20  10  40  20  20
Omak           30  41  27  37  26  37 /  30  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands.

&&

$$





000
FXUS66 KOTX 220636
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1036 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest. Windy conditions with mountain
snow showers are expected on Saturday and Sunday. An active and
somewhat wet weather regime will continue into the first half of
next week.



&&

.DISCUSSION...
The cold front has passed through the East Slopes and the threat
for heavy snow has ended in the lee of the Cascades. We got some
impressive snowfall totals from a few locations including 6" near
Oroville, 7" in Leavenworth, 6" just outside Malott, and 4" in
Waterville to name a few. Anyway, the cooler and unstable air mass
behind the front coupled with strong westerly winds will end the
threat for heavy snow in the lee of the Cascades and we have
cancelled the winter weather highlights early. We will leave the
highlights along the East Slopes dealing with unstable heavy snow
showers along the crest and some slop over into the upper
valleys. The most intense bands will come from a Puget Sound
Convergence Zone which is starting to set as of 1030PM and HRRR
suggest it will sag south through Chelan County
overnight...potentially reaching to the Hwy 97 corridor (at least
some lighter activity).

Steady precipitation is currently moving through far Ern WA and
the Idaho Panhandle. Snow levels are near 4500` but will be coming
down as the cooler air moves east. This will also transition pcpn
more showery but continue to bring moderate to heavy mountain snow
accumulations. The basin will continue to dry out with the most
persistent lowland showers across SE WA.

&&

.AVIATION...
06Z TAFS: Snow has winded down in the lee of the Cascades with the
passage of a cold front. It will take some time to break the low-
level inversions and completely scrub out the moist boundary layer
conditions and this will promote low-level wind shear for a few
hours. Once southwest winds mix to the surface, llws will end and
gusty winds will deliver improving VIS and CIG. -shsn will
continue along the Cascade Crest and mountains of ID through much
of Saturday continuing to bring mtn obscrns. A second wave looks
to renew a threat for showers across SE WA and Nrn ID aft 22z. /sb



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        33  41  30  38  29  37 /  60  20  20  70  30  20
Coeur d`Alene  35  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        38  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       43  47  37  45  33  44 / 100  70  40  80  50  20
Colville       32  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      32  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        34  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     31  46  28  43  30  42 /  20  10  10  30  10  20
Wenatchee      33  43  33  42  32  42 /  20  20  10  40  20  20
Omak           30  41  27  37  26  37 /  30  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands.

&&

$$






000
FXUS66 KOTX 220451
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
851 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest. Windy conditions with mountain
snow showers are expected on Saturday and Sunday. An active and
somewhat wet weather regime will continue into the first half of
next week.


&&

.DISCUSSION...
Several updates this evening: Overall picture shows the cold front
is currently crossing the Cascades and wintry precip will be
shutting down in the lee of the Cascades then across the Basin while
intensifying in the ID Panhandle and NE WA. Here are the other
main points in the update

Near the Cascades:
- Freezing rain threat has diminished and advisory will be allowed
to expire.
- Cooler air is arriving aloft and snow is becoming more
convective, thus producing rates near 1.00"/hour.
- The unstable and strong westerly flow will likely slop snow
showers over the crest for much of the night. Models indicate a
strong Puget Sound Convergence Zone developing as well. Winter
storm warnings will remain in place
- Snow is also wet and heavy and caused power outages near
Cashmere as well as numerous accidents in Wenatchee and near
Malott. I am sure there are more which we have not heard of yet.
- Snow will taper off in the next hour along the Hwy 97 corridor
except in the far southern Chelan County near Blewett Pass.
- Mountain winds have been increased with 50-70kts of wind
expected at 700mb. The sensor on the top of Mission Ridge is
already gusting to 58 mph.

Central and East:
- Not many edits except to lower PoPs in the Basin toward the
Spokane Area a bit quicker.
- Snow levels currently near 4500 ft in Nrn ID and NE WA with a
few exceptions.
- Cool air remains trapped into localized valleys near the
Canadian Border and vicinity of Priest Lake and could lead to
snow or brief freezing rain. - Winds were increased in the
foothills of the Blue Mtns.

/sb


&&

.AVIATION...
00Z TAFS: A very moist Pacific storm system is already spreading
through the basin at this hour and will move east through the
forecast this evening. Expect a mix of -SN/-RA/-FZRA for KEAT
where deeper cold air will be slower to erode...IFR/LIFR cigs/vsby
will improve to MVFR aft 04z. At KMWH -FZPL was reported but is
now -RA. Thinking at this time that precipitation should stay as
-RA...IFR cigs/vsby will continue through the night. Precipitation
will track east through the evening...mainly as rain for all
eastern TAF sites. VFR/MVFR conditions for KGEG/KSFF/KCOE will
deteriorate aft 02-03z as precipitation increases to mainly
MVFR...then decrease to IFR if not LIFR aft 07-09Z behind the
precipitation as stratus/fog develops...then improving after 21Z
Saturday. KPUW/KLWS should remain VFR/MVFR cigs/vsby. Southwest
winds will increase after 12-14z at all sites with gusts 25-30kts.
/Tobin


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        35  41  30  38  29  37 / 100  20  20  70  30  20
Coeur d`Alene  36  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        37  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       41  47  37  45  33  44 / 100  70  40  80  50  20
Colville       34  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      34  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        35  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     32  46  28  43  30  42 / 100  10  10  30  10  20
Wenatchee      34  43  33  42  32  42 / 100  20  10  40  20  20
Omak           31  41  27  37  26  37 / 100  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

     Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Freezing Rain Advisory until 9 PM PST this evening for Moses
     Lake Area.

&&

$$






000
FXUS66 KOTX 220451
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
851 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest. Windy conditions with mountain
snow showers are expected on Saturday and Sunday. An active and
somewhat wet weather regime will continue into the first half of
next week.


&&

.DISCUSSION...
Several updates this evening: Overall picture shows the cold front
is currently crossing the Cascades and wintry precip will be
shutting down in the lee of the Cascades then across the Basin while
intensifying in the ID Panhandle and NE WA. Here are the other
main points in the update

Near the Cascades:
- Freezing rain threat has diminished and advisory will be allowed
to expire.
- Cooler air is arriving aloft and snow is becoming more
convective, thus producing rates near 1.00"/hour.
- The unstable and strong westerly flow will likely slop snow
showers over the crest for much of the night. Models indicate a
strong Puget Sound Convergence Zone developing as well. Winter
storm warnings will remain in place
- Snow is also wet and heavy and caused power outages near
Cashmere as well as numerous accidents in Wenatchee and near
Malott. I am sure there are more which we have not heard of yet.
- Snow will taper off in the next hour along the Hwy 97 corridor
except in the far southern Chelan County near Blewett Pass.
- Mountain winds have been increased with 50-70kts of wind
expected at 700mb. The sensor on the top of Mission Ridge is
already gusting to 58 mph.

Central and East:
- Not many edits except to lower PoPs in the Basin toward the
Spokane Area a bit quicker.
- Snow levels currently near 4500 ft in Nrn ID and NE WA with a
few exceptions.
- Cool air remains trapped into localized valleys near the
Canadian Border and vicinity of Priest Lake and could lead to
snow or brief freezing rain. - Winds were increased in the
foothills of the Blue Mtns.

/sb


&&

.AVIATION...
00Z TAFS: A very moist Pacific storm system is already spreading
through the basin at this hour and will move east through the
forecast this evening. Expect a mix of -SN/-RA/-FZRA for KEAT
where deeper cold air will be slower to erode...IFR/LIFR cigs/vsby
will improve to MVFR aft 04z. At KMWH -FZPL was reported but is
now -RA. Thinking at this time that precipitation should stay as
-RA...IFR cigs/vsby will continue through the night. Precipitation
will track east through the evening...mainly as rain for all
eastern TAF sites. VFR/MVFR conditions for KGEG/KSFF/KCOE will
deteriorate aft 02-03z as precipitation increases to mainly
MVFR...then decrease to IFR if not LIFR aft 07-09Z behind the
precipitation as stratus/fog develops...then improving after 21Z
Saturday. KPUW/KLWS should remain VFR/MVFR cigs/vsby. Southwest
winds will increase after 12-14z at all sites with gusts 25-30kts.
/Tobin


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        35  41  30  38  29  37 / 100  20  20  70  30  20
Coeur d`Alene  36  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        37  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       41  47  37  45  33  44 / 100  70  40  80  50  20
Colville       34  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      34  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        35  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     32  46  28  43  30  42 / 100  10  10  30  10  20
Wenatchee      34  43  33  42  32  42 / 100  20  10  40  20  20
Omak           31  41  27  37  26  37 / 100  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

     Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Freezing Rain Advisory until 9 PM PST this evening for Moses
     Lake Area.

&&

$$





000
FXUS66 KOTX 220109
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
509 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest. Windy conditions with mountain
snow showers are expected on Saturday and Sunday. An active and
somewhat wet weather regime will continue into the first half of
next week.


&&

.DISCUSSION...
We have issued a freezing rain advisory for southern Grant County.
The cooler air is being stubborn mainly west of a line from
Othello to Moses lake with freezing rain and icy conditions reported
in Ephrata. Snow has been falling in Quincy and rain in Moses Lake so
the dome of cold air is currently slicing right through this area.
LAMP guidance suggest temperatures will remain steady then fall a
degree or two overnight with the cold front passage. Consequently,
as the mixed wintry precip ends, conditions will likely remain
icy through Saturday morning. The end time of the freezing rain
advisory correlates to when the precipitation should end. This
will also lead to earlier termination of winter wx highlights
along the Hwy 97 corridor but will wait for the actual cold front
passage before doing so. /sb


&&

.AVIATION...
00Z TAFS: A very moist Pacific storm system is already spreading
through the basin at this hour and will move east through the
forecast this evening. Expect a mix of -SN/-RA/-FZRA for KEAT
where deeper cold air will be slower to erode...IFR/LIFR cigs/vsby
will improve to MVFR aft 04z. At KMWH -FZPL was reported but is
now -RA. Thinking at this time that precipitation should stay as
-RA...IFR cigs/vsby will continue through the night. Precipitation
will track east through the evening...mainly as rain for all
eastern TAF sites. VFR/MVFR conditions for KGEG/KSFF/KCOE will
deteriorate aft 02-03z as precipitation increases to mainly
MVFR...then decrease to IFR if not LIFR aft 07-09Z behind the
precipitation as stratus/fog develops...then improving after 21Z
Saturday. KPUW/KLWS should remain VFR/MVFR cigs/vsby. Southwest
winds will increase after 12-14z at all sites with gusts 25-30kts.
/Tobin


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        35  41  30  38  29  37 / 100  20  20  70  30  20
Coeur d`Alene  36  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        37  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       41  47  37  45  33  44 / 100  70  40  80  50  20
Colville       34  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      34  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        35  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     32  46  28  43  30  42 / 100  10  10  30  10  20
Wenatchee      34  43  33  42  32  42 / 100  20  10  40  20  20
Omak           31  41  27  37  26  37 / 100  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

     Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Freezing Rain Advisory until 9 PM PST this evening for Moses
     Lake Area.

&&

$$






000
FXUS66 KOTX 220109
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
509 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest. Windy conditions with mountain
snow showers are expected on Saturday and Sunday. An active and
somewhat wet weather regime will continue into the first half of
next week.


&&

.DISCUSSION...
We have issued a freezing rain advisory for southern Grant County.
The cooler air is being stubborn mainly west of a line from
Othello to Moses lake with freezing rain and icy conditions reported
in Ephrata. Snow has been falling in Quincy and rain in Moses Lake so
the dome of cold air is currently slicing right through this area.
LAMP guidance suggest temperatures will remain steady then fall a
degree or two overnight with the cold front passage. Consequently,
as the mixed wintry precip ends, conditions will likely remain
icy through Saturday morning. The end time of the freezing rain
advisory correlates to when the precipitation should end. This
will also lead to earlier termination of winter wx highlights
along the Hwy 97 corridor but will wait for the actual cold front
passage before doing so. /sb


&&

.AVIATION...
00Z TAFS: A very moist Pacific storm system is already spreading
through the basin at this hour and will move east through the
forecast this evening. Expect a mix of -SN/-RA/-FZRA for KEAT
where deeper cold air will be slower to erode...IFR/LIFR cigs/vsby
will improve to MVFR aft 04z. At KMWH -FZPL was reported but is
now -RA. Thinking at this time that precipitation should stay as
-RA...IFR cigs/vsby will continue through the night. Precipitation
will track east through the evening...mainly as rain for all
eastern TAF sites. VFR/MVFR conditions for KGEG/KSFF/KCOE will
deteriorate aft 02-03z as precipitation increases to mainly
MVFR...then decrease to IFR if not LIFR aft 07-09Z behind the
precipitation as stratus/fog develops...then improving after 21Z
Saturday. KPUW/KLWS should remain VFR/MVFR cigs/vsby. Southwest
winds will increase after 12-14z at all sites with gusts 25-30kts.
/Tobin


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        35  41  30  38  29  37 / 100  20  20  70  30  20
Coeur d`Alene  36  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        37  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       41  47  37  45  33  44 / 100  70  40  80  50  20
Colville       34  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      34  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        35  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     32  46  28  43  30  42 / 100  10  10  30  10  20
Wenatchee      34  43  33  42  32  42 / 100  20  10  40  20  20
Omak           31  41  27  37  26  37 / 100  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

     Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Freezing Rain Advisory until 9 PM PST this evening for Moses
     Lake Area.

&&

$$





000
FXUS66 KOTX 220008
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
408 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest. Windy conditions with mountain
snow showers are expected on Saturday and Sunday. An active and
somewhat wet weather regime will continue into the first half of
next week.

&&

.DISCUSSION...
Tonight...Expect wet and snowy weather as a slug of Pacific
moisture streams into the Inland NW. A warm front will sweep
through the region early this evening and provide the focus for a
swath of moderate to heavy precipitation. The main issue continues
to be precipitation type as this warm air eats away from the
prevailing colder air mass. So far the Cascades have been under
the main area of precipitation. Due to the weak easterly low level
flow and the damning of the cold air in the valleys, the bulk of
the precipitation has fallen as snow and this will continue
through the night. Some warm air has crept up the Wenatchee valley
and lead to some freezing rain; an oscillation of snow to mixed
precipitation is possible before it tapers off. A dome of cold air
also lies from the Okanogan valley, across the Waterville Plateau
to the Moses Lake area. So far, surface temperatures and wet bulb
zeros show snow levels right near the surface and could see a
wintry mix of snow, freezing rain and sleet as snow levels
gradually creep to 2k to 2500 feet. East of a line from Ritzville
to Kettle Falls, the warm air has moved into the valleys and
expect a valley rain/mountain snow event overnight. The moderate
rainfall may lead to ponding of water across portions of the
Columbia Basin and Palouse as the ground remains frozen. A cold
front will sweep through the region overnight and allow the
precipitation to taper off from west to east. Expect the
precipitation to linger over north Idaho through the night with
moderate amounts of mountain snow. Overnight lows will be
challenging, but shouldn`t fall too much, lingering near current
dewpoints. Expect no major changes to the current winter
highlights. /rfox.

Saturday through Monday...The active pattern will continue
through the weekend and into the first part of next week as a
series of weather disturbances moves through the region. Then high
pressure will begin to build into the region Monday, but not
before one last weather system sneaks through the region.

Saturday and Saturday night the atmosphere will dry out from west
to east through the day on Saturday and result in a drying trend
with breezy winds through the day. Southwest winds of 15-25 mph
with gusts 35-40 mph will be possible. Temperatures, at least,
will warm into the upper 30s to mid 40s.

Model guidance has been consistent showing the atmosphere
destabilizing Saturday with the trough axis. Lapse rates are
actually quite impressive after 18z across the central and
northern Idaho Panhandle. As weak high pressure builds in behind
the front the surface to mid level flow will become west-
northwest. This puts the focus of the best precipitation to the
northeast zones and the Idaho Panhandle, with a secondary area for
slop over snow showers near the Cascade crest. Showers will likely
back build into the Idaho Palouse and as far east as the Spokane-
Coeur D`Alene area. With the instability that will be present
there will be a good chance for periods of very heavy rain and
snow showers for the central Panhandle and portions of the north
Panhandle. Snow levels will rise to between 2500-3000 ft by the
afternoon, which would mean valley rain and mountain snow.
Additional accumulations of 2-3 inches for the north Panhandle
mountains and 3-5 inches for the central Panhandle mountains will
be very possible. As such we will keep the winter highlights up
for the north Panhandle through Saturday afternoon and for
Shoshone county through Sunday morning.

Precipitation chances will begin to decrease late Saturday night
for the eastern zones, but will be on the increase for the
Cascades as the next quick hitting weather disturbance moves into
the region. The warm front will be on the Cascades by 12z Sunday
with the occlusion following roughly 6 hours later. This will
bring another round of stratiform precipitation to the region.
Model guidance has indicated some moderate to heavy precipitation
with this disturbance as well. Snow levels range from 3500 ft
across the south to 1500 feet or maybe less across the north. So
rain in the valley with mountain snow. At this time 12 hour snow
totals may push snow advisory criteria for the central Panhandle.
There are plenty of highlights out right now for weather in the
short term and we will keep an eye on this to either extend or add
new winter highlights all together. Winds will remain elevated but
should be 5-10 mph weaker on Sunday.

High pressure will slowly build back into the region Sunday night
into Monday. This will result in drier conditions Sunday night and
early Monday. However one weather disturbance will move through
the building ridge late in the day on Monday and bring a last shot
of moisture to the region, at least for this series of storms. /Tobin


Monday night through the day after Thanksgiving: Much better model
agreement today, at least through Wednesday, then there is
a little less agreement thereafter. Yesterday`s outlier of a large
upper level ridge traversing the region midweek is now today`s
consensus. But one last disturbance will bring rain and snow to
the Inland Northwest Monday night into Tuesday. Given the flow
pattern, the Idaho Panhandle and the mountains of northeast
Washington will be affected most, as well as over the Cascade
crest. Enough cold air may be present during the onset that the
valleys may see snow, but increasing snow levels on Tuesday should
switch many of the valleys that are still seeing precipitation to
rain. The ridge builds in Tuesday night and Wednesday, ending any
significant threat for precipitation. This should be good news for
those that will be traveling through the Inland Northwest on
Wednesday. Uncertainty exists on Thanksgiving day and the day
after. It should be an active weather pattern, but no significant
weather systems are expected through Friday. Precipitation chances
were trended toward climatology for the latter two days of the
Holiday week. Temperatures were bumped up some from the previous
forecast, but only by a degree or two. ty

&&

.AVIATION...
00Z TAFS: A very moist Pacific storm system is already spreading
through the basin at this hour and will move east through the
forecast this evening. Expect a mix of -SN/-RA/-FZRA for KEAT
where deeper cold air will be slower to erode...IFR/LIFR cigs/vsby
will improve to MVFR aft 04z. At KMWH -FZPL was reported but is
now -RA. Thinking at this time that precipitation should stay as
-RA...IFR cigs/vsby will continue through the night. Precipitation
will track east through the evening...mainly as rain for all
eastern TAF sites. VFR/MVFR conditions for KGEG/KSFF/KCOE will
deteriorate aft 02-03z as precipitation increases to mainly
MVFR...then decrease to IFR if not LIFR aft 07-09Z behind the
precipitation as stratus/fog develops...then improving after 21Z
Saturday. KPUW/KLWS should remain VFR/MVFR cigs/vsby. Southwest
winds will increase after 12-14z at all sites with gusts 25-30kts.
/Tobin

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        35  41  30  38  29  37 / 100  20  20  70  30  20
Coeur d`Alene  36  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        37  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       41  47  37  45  33  44 / 100  70  40  80  50  20
Colville       34  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      34  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        35  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     32  46  28  43  30  42 / 100  10  10  30  10  20
Wenatchee      34  43  33  42  32  42 / 100  20  10  40  20  20
Omak           31  41  27  37  26  37 / 100  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

&&

$$





000
FXUS66 KOTX 220008
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
408 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest. Windy conditions with mountain
snow showers are expected on Saturday and Sunday. An active and
somewhat wet weather regime will continue into the first half of
next week.

&&

.DISCUSSION...
Tonight...Expect wet and snowy weather as a slug of Pacific
moisture streams into the Inland NW. A warm front will sweep
through the region early this evening and provide the focus for a
swath of moderate to heavy precipitation. The main issue continues
to be precipitation type as this warm air eats away from the
prevailing colder air mass. So far the Cascades have been under
the main area of precipitation. Due to the weak easterly low level
flow and the damning of the cold air in the valleys, the bulk of
the precipitation has fallen as snow and this will continue
through the night. Some warm air has crept up the Wenatchee valley
and lead to some freezing rain; an oscillation of snow to mixed
precipitation is possible before it tapers off. A dome of cold air
also lies from the Okanogan valley, across the Waterville Plateau
to the Moses Lake area. So far, surface temperatures and wet bulb
zeros show snow levels right near the surface and could see a
wintry mix of snow, freezing rain and sleet as snow levels
gradually creep to 2k to 2500 feet. East of a line from Ritzville
to Kettle Falls, the warm air has moved into the valleys and
expect a valley rain/mountain snow event overnight. The moderate
rainfall may lead to ponding of water across portions of the
Columbia Basin and Palouse as the ground remains frozen. A cold
front will sweep through the region overnight and allow the
precipitation to taper off from west to east. Expect the
precipitation to linger over north Idaho through the night with
moderate amounts of mountain snow. Overnight lows will be
challenging, but shouldn`t fall too much, lingering near current
dewpoints. Expect no major changes to the current winter
highlights. /rfox.

Saturday through Monday...The active pattern will continue
through the weekend and into the first part of next week as a
series of weather disturbances moves through the region. Then high
pressure will begin to build into the region Monday, but not
before one last weather system sneaks through the region.

Saturday and Saturday night the atmosphere will dry out from west
to east through the day on Saturday and result in a drying trend
with breezy winds through the day. Southwest winds of 15-25 mph
with gusts 35-40 mph will be possible. Temperatures, at least,
will warm into the upper 30s to mid 40s.

Model guidance has been consistent showing the atmosphere
destabilizing Saturday with the trough axis. Lapse rates are
actually quite impressive after 18z across the central and
northern Idaho Panhandle. As weak high pressure builds in behind
the front the surface to mid level flow will become west-
northwest. This puts the focus of the best precipitation to the
northeast zones and the Idaho Panhandle, with a secondary area for
slop over snow showers near the Cascade crest. Showers will likely
back build into the Idaho Palouse and as far east as the Spokane-
Coeur D`Alene area. With the instability that will be present
there will be a good chance for periods of very heavy rain and
snow showers for the central Panhandle and portions of the north
Panhandle. Snow levels will rise to between 2500-3000 ft by the
afternoon, which would mean valley rain and mountain snow.
Additional accumulations of 2-3 inches for the north Panhandle
mountains and 3-5 inches for the central Panhandle mountains will
be very possible. As such we will keep the winter highlights up
for the north Panhandle through Saturday afternoon and for
Shoshone county through Sunday morning.

Precipitation chances will begin to decrease late Saturday night
for the eastern zones, but will be on the increase for the
Cascades as the next quick hitting weather disturbance moves into
the region. The warm front will be on the Cascades by 12z Sunday
with the occlusion following roughly 6 hours later. This will
bring another round of stratiform precipitation to the region.
Model guidance has indicated some moderate to heavy precipitation
with this disturbance as well. Snow levels range from 3500 ft
across the south to 1500 feet or maybe less across the north. So
rain in the valley with mountain snow. At this time 12 hour snow
totals may push snow advisory criteria for the central Panhandle.
There are plenty of highlights out right now for weather in the
short term and we will keep an eye on this to either extend or add
new winter highlights all together. Winds will remain elevated but
should be 5-10 mph weaker on Sunday.

High pressure will slowly build back into the region Sunday night
into Monday. This will result in drier conditions Sunday night and
early Monday. However one weather disturbance will move through
the building ridge late in the day on Monday and bring a last shot
of moisture to the region, at least for this series of storms. /Tobin


Monday night through the day after Thanksgiving: Much better model
agreement today, at least through Wednesday, then there is
a little less agreement thereafter. Yesterday`s outlier of a large
upper level ridge traversing the region midweek is now today`s
consensus. But one last disturbance will bring rain and snow to
the Inland Northwest Monday night into Tuesday. Given the flow
pattern, the Idaho Panhandle and the mountains of northeast
Washington will be affected most, as well as over the Cascade
crest. Enough cold air may be present during the onset that the
valleys may see snow, but increasing snow levels on Tuesday should
switch many of the valleys that are still seeing precipitation to
rain. The ridge builds in Tuesday night and Wednesday, ending any
significant threat for precipitation. This should be good news for
those that will be traveling through the Inland Northwest on
Wednesday. Uncertainty exists on Thanksgiving day and the day
after. It should be an active weather pattern, but no significant
weather systems are expected through Friday. Precipitation chances
were trended toward climatology for the latter two days of the
Holiday week. Temperatures were bumped up some from the previous
forecast, but only by a degree or two. ty

&&

.AVIATION...
00Z TAFS: A very moist Pacific storm system is already spreading
through the basin at this hour and will move east through the
forecast this evening. Expect a mix of -SN/-RA/-FZRA for KEAT
where deeper cold air will be slower to erode...IFR/LIFR cigs/vsby
will improve to MVFR aft 04z. At KMWH -FZPL was reported but is
now -RA. Thinking at this time that precipitation should stay as
-RA...IFR cigs/vsby will continue through the night. Precipitation
will track east through the evening...mainly as rain for all
eastern TAF sites. VFR/MVFR conditions for KGEG/KSFF/KCOE will
deteriorate aft 02-03z as precipitation increases to mainly
MVFR...then decrease to IFR if not LIFR aft 07-09Z behind the
precipitation as stratus/fog develops...then improving after 21Z
Saturday. KPUW/KLWS should remain VFR/MVFR cigs/vsby. Southwest
winds will increase after 12-14z at all sites with gusts 25-30kts.
/Tobin

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        35  41  30  38  29  37 / 100  20  20  70  30  20
Coeur d`Alene  36  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        37  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       41  47  37  45  33  44 / 100  70  40  80  50  20
Colville       34  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      34  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        35  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     32  46  28  43  30  42 / 100  10  10  30  10  20
Wenatchee      34  43  33  42  32  42 / 100  20  10  40  20  20
Omak           31  41  27  37  26  37 / 100  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

&&

$$






000
FXUS66 KOTX 212244
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest overnight. Windy conditions
with mountain snow showers are expected on Saturday and Sunday. An
active and somewhat wet weather regime will continue into the
first half of next week.

&&

.DISCUSSION...
Tonight...Expect wet and snowy weather as a slug of Pacific
moisture streams into the Inland NW. A warm front will sweep
through the region early this evening and provide the focus for a
swath of moderate to heavy precipitation. The main issue continues
to be precipitation type as this warm air eats away from the
prevailing colder air mass. So far the Cascades have been under
the main area of precipitation. Due to the weak easterly low level
flow and the damning of the cold air in the valleys, the bulk of
the precipitation has fallen as snow and this will continue
through the night. Some warm air has crept up the Wenatchee valley
and lead to some freezing rain; an oscillation of snow to mixed
precipitation is possible before it tapers off. A dome of cold air
also lies from the Okanogan valley, across the Waterville Plateau
to the Moses Lake area. So far, surface temperatures and wet bulb
zeros show snow levels right near the surface and could see a
wintry mix of snow, freezing rain and sleet as snow levels
gradually creep to 2k to 2500 feet. East of a line from Ritzville
to Kettle Falls, the warm air has moved into the valleys and
expect a valley rain/mountain snow event overnight. The moderate
rainfall may lead to ponding of water across portions of the
Columbia Basin and Palouse as the ground remains frozen. A cold
front will sweep through the region overnight and allow the
precipitation to taper off from west to east. Expect the
precipitation to linger over north Idaho through the night with
moderate amounts of mountain snow. Overnight lows will be
challenging, but shouldn`t fall too much, lingering near current
dewpoints. Expect no major changes to the current winter
highlights. /rfox.

Saturday through Monday...The active pattern will continue
through the weekend and into the first part of next week as a
series of weather disturbances moves through the region. Then high
pressure will begin to build into the region Monday, but not
before one last weather system sneaks through the region.

Saturday and Saturday night the atmosphere will dry out from west
to east through the day on Saturday and result in a drying trend
with breezy winds through the day. Southwest winds of 15-25 mph
with gusts 35-40 mph will be possible. Temperatures, at least,
will warm into the upper 30s to mid 40s.

Model guidance has been consistent showing the atmosphere
destabilizing Saturday with the trough axis. Lapse rates are
actually quite impressive after 18z across the central and
northern Idaho Panhandle. As weak high pressure builds in behind
the front the surface to mid level flow will become west-
northwest. This puts the focus of the best precipitation to the
northeast zones and the Idaho Panhandle, with a secondary area for
slop over snow showers near the Cascade crest. Showers will likely
back build into the Idaho Palouse and as far east as the Spokane-
Coeur D`Alene area. With the instability that will be present
there will be a good chance for periods of very heavy rain and
snow showers for the central Panhandle and portions of the north
Panhandle. Snow levels will rise to between 2500-3000 ft by the
afternoon, which would mean valley rain and mountain snow.
Additional accumulations of 2-3 inches for the north Panhandle
mountains and 3-5 inches for the central Panhandle mountains will
be very possible. As such we will keep the winter highlights up
for the north Panhandle through Saturday afternoon and for
Shoshone county through Sunday morning.

Precipitation chances will begin to decrease late Saturday night
for the eastern zones, but will be on the increase for the
Cascades as the next quick hitting weather disturbance moves into
the region. The warm front will be on the Cascades by 12z Sunday
with the occlusion following roughly 6 hours later. This will
bring another round of stratiform precipitation to the region.
Model guidance has indicated some moderate to heavy precipitation
with this disturbance as well. Snow levels range from 3500 ft
across the south to 1500 feet or maybe less across the north. So
rain in the valley with mountain snow. At this time 12 hour snow
totals may push snow advisory criteria for the central Panhandle.
There are plenty of highlights out right now for weather in the
short term and we will keep an eye on this to either extend or add
new winter highlights all together. Winds will remain elevated but
should be 5-10 mph weaker on Sunday.

High pressure will slowly build back into the region Sunday night
into Monday. This will result in drier conditions Sunday night and
early Monday. However one weather disturbance will move through
the building ridge late in the day on Monday and bring a last shot
of moisture to the region, at least for this series of storms. /Tobin


Monday night through the day after Thanksgiving: Much better model
agreement today, at least through Wednesday, then there is
a little less agreement thereafter. Yesterday`s outlier of a large
upper level ridge traversing the region midweek is now today`s
consensus. But one last disturbance will bring rain and snow to
the Inland Northwest Monday night into Tuesday. Given the flow
pattern, the Idaho Panhandle and the mountains of northeast
Washington will be affected most, as well as over the Cascade
crest. Enough cold air may be present during the onset that the
valleys may see snow, but increasing snow levels on Tuesday should
switch many of the valleys that are still seeing precipitation to
rain. The ridge builds in Tuesday night and Wednesday, ending any
significant threat for precipitation. This should be good news for
those that will be traveling through the Inland Northwest on
Wednesday. Uncertainty exists on Thanksgiving day and the day
after. It should be an active weather pattern, but no significant
weather systems are expected through Friday. Precipitation chances
were trended toward climatology for the latter two days of the
Holiday week. Temperatures were bumped up some from the previous
forecast, but only by a degree or two. ty

&&

.AVIATION...
18Z TAFS: Cigs and vsbys will improve this morning as the low
levels mix ahead of the advancing warm front from KEAT to KGEG.
VFR conditions will prevail from KPUW to KLWS under light east to
southeast winds. A very moist Pacific storm system will spread
-SN/-RA from the Cascades eastward through the afternoon. Did slow
down the timing slightly with the main precipitation reaching KEAT
after 21z, KMWH 22z and KGEG after 00z. Pcpn will vary btwn -SN,
-RA and -FZRA at KEAT and possibly KMWH and could be moderate at
times. Warmer conditions will bring rain to KGEG/KSFF/KCOE/KPUW/KLWS.
Ceilings with the precipitation are once again expected to drop to
MVFR or even IFR conditions. By Saturday morning, post frontal
westerly winds will increase, although some areas of MVFR
cigs/vsbys will linger. /rfox

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        35  41  30  38  29  37 / 100  20  20  70  30  20
Coeur d`Alene  36  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        37  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       41  47  37  45  33  44 / 100  70  40  80  50  20
Colville       34  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      34  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        35  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     32  46  28  43  30  42 / 100  10  10  30  10  20
Wenatchee      34  43  33  42  32  42 / 100  20  10  40  20  20
Omak           31  41  27  37  26  37 / 100  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

&&

$$






000
FXUS66 KOTX 212244
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest overnight. Windy conditions
with mountain snow showers are expected on Saturday and Sunday. An
active and somewhat wet weather regime will continue into the
first half of next week.

&&

.DISCUSSION...
Tonight...Expect wet and snowy weather as a slug of Pacific
moisture streams into the Inland NW. A warm front will sweep
through the region early this evening and provide the focus for a
swath of moderate to heavy precipitation. The main issue continues
to be precipitation type as this warm air eats away from the
prevailing colder air mass. So far the Cascades have been under
the main area of precipitation. Due to the weak easterly low level
flow and the damning of the cold air in the valleys, the bulk of
the precipitation has fallen as snow and this will continue
through the night. Some warm air has crept up the Wenatchee valley
and lead to some freezing rain; an oscillation of snow to mixed
precipitation is possible before it tapers off. A dome of cold air
also lies from the Okanogan valley, across the Waterville Plateau
to the Moses Lake area. So far, surface temperatures and wet bulb
zeros show snow levels right near the surface and could see a
wintry mix of snow, freezing rain and sleet as snow levels
gradually creep to 2k to 2500 feet. East of a line from Ritzville
to Kettle Falls, the warm air has moved into the valleys and
expect a valley rain/mountain snow event overnight. The moderate
rainfall may lead to ponding of water across portions of the
Columbia Basin and Palouse as the ground remains frozen. A cold
front will sweep through the region overnight and allow the
precipitation to taper off from west to east. Expect the
precipitation to linger over north Idaho through the night with
moderate amounts of mountain snow. Overnight lows will be
challenging, but shouldn`t fall too much, lingering near current
dewpoints. Expect no major changes to the current winter
highlights. /rfox.

Saturday through Monday...The active pattern will continue
through the weekend and into the first part of next week as a
series of weather disturbances moves through the region. Then high
pressure will begin to build into the region Monday, but not
before one last weather system sneaks through the region.

Saturday and Saturday night the atmosphere will dry out from west
to east through the day on Saturday and result in a drying trend
with breezy winds through the day. Southwest winds of 15-25 mph
with gusts 35-40 mph will be possible. Temperatures, at least,
will warm into the upper 30s to mid 40s.

Model guidance has been consistent showing the atmosphere
destabilizing Saturday with the trough axis. Lapse rates are
actually quite impressive after 18z across the central and
northern Idaho Panhandle. As weak high pressure builds in behind
the front the surface to mid level flow will become west-
northwest. This puts the focus of the best precipitation to the
northeast zones and the Idaho Panhandle, with a secondary area for
slop over snow showers near the Cascade crest. Showers will likely
back build into the Idaho Palouse and as far east as the Spokane-
Coeur D`Alene area. With the instability that will be present
there will be a good chance for periods of very heavy rain and
snow showers for the central Panhandle and portions of the north
Panhandle. Snow levels will rise to between 2500-3000 ft by the
afternoon, which would mean valley rain and mountain snow.
Additional accumulations of 2-3 inches for the north Panhandle
mountains and 3-5 inches for the central Panhandle mountains will
be very possible. As such we will keep the winter highlights up
for the north Panhandle through Saturday afternoon and for
Shoshone county through Sunday morning.

Precipitation chances will begin to decrease late Saturday night
for the eastern zones, but will be on the increase for the
Cascades as the next quick hitting weather disturbance moves into
the region. The warm front will be on the Cascades by 12z Sunday
with the occlusion following roughly 6 hours later. This will
bring another round of stratiform precipitation to the region.
Model guidance has indicated some moderate to heavy precipitation
with this disturbance as well. Snow levels range from 3500 ft
across the south to 1500 feet or maybe less across the north. So
rain in the valley with mountain snow. At this time 12 hour snow
totals may push snow advisory criteria for the central Panhandle.
There are plenty of highlights out right now for weather in the
short term and we will keep an eye on this to either extend or add
new winter highlights all together. Winds will remain elevated but
should be 5-10 mph weaker on Sunday.

High pressure will slowly build back into the region Sunday night
into Monday. This will result in drier conditions Sunday night and
early Monday. However one weather disturbance will move through
the building ridge late in the day on Monday and bring a last shot
of moisture to the region, at least for this series of storms. /Tobin


Monday night through the day after Thanksgiving: Much better model
agreement today, at least through Wednesday, then there is
a little less agreement thereafter. Yesterday`s outlier of a large
upper level ridge traversing the region midweek is now today`s
consensus. But one last disturbance will bring rain and snow to
the Inland Northwest Monday night into Tuesday. Given the flow
pattern, the Idaho Panhandle and the mountains of northeast
Washington will be affected most, as well as over the Cascade
crest. Enough cold air may be present during the onset that the
valleys may see snow, but increasing snow levels on Tuesday should
switch many of the valleys that are still seeing precipitation to
rain. The ridge builds in Tuesday night and Wednesday, ending any
significant threat for precipitation. This should be good news for
those that will be traveling through the Inland Northwest on
Wednesday. Uncertainty exists on Thanksgiving day and the day
after. It should be an active weather pattern, but no significant
weather systems are expected through Friday. Precipitation chances
were trended toward climatology for the latter two days of the
Holiday week. Temperatures were bumped up some from the previous
forecast, but only by a degree or two. ty

&&

.AVIATION...
18Z TAFS: Cigs and vsbys will improve this morning as the low
levels mix ahead of the advancing warm front from KEAT to KGEG.
VFR conditions will prevail from KPUW to KLWS under light east to
southeast winds. A very moist Pacific storm system will spread
-SN/-RA from the Cascades eastward through the afternoon. Did slow
down the timing slightly with the main precipitation reaching KEAT
after 21z, KMWH 22z and KGEG after 00z. Pcpn will vary btwn -SN,
-RA and -FZRA at KEAT and possibly KMWH and could be moderate at
times. Warmer conditions will bring rain to KGEG/KSFF/KCOE/KPUW/KLWS.
Ceilings with the precipitation are once again expected to drop to
MVFR or even IFR conditions. By Saturday morning, post frontal
westerly winds will increase, although some areas of MVFR
cigs/vsbys will linger. /rfox

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        35  41  30  38  29  37 / 100  20  20  70  30  20
Coeur d`Alene  36  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        37  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       41  47  37  45  33  44 / 100  70  40  80  50  20
Colville       34  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      34  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        35  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     32  46  28  43  30  42 / 100  10  10  30  10  20
Wenatchee      34  43  33  42  32  42 / 100  20  10  40  20  20
Omak           31  41  27  37  26  37 / 100  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

&&

$$





000
FXUS66 KOTX 212244
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 PM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring rain and snow through
the night across Inland Northwest overnight. Windy conditions
with mountain snow showers are expected on Saturday and Sunday. An
active and somewhat wet weather regime will continue into the
first half of next week.

&&

.DISCUSSION...
Tonight...Expect wet and snowy weather as a slug of Pacific
moisture streams into the Inland NW. A warm front will sweep
through the region early this evening and provide the focus for a
swath of moderate to heavy precipitation. The main issue continues
to be precipitation type as this warm air eats away from the
prevailing colder air mass. So far the Cascades have been under
the main area of precipitation. Due to the weak easterly low level
flow and the damning of the cold air in the valleys, the bulk of
the precipitation has fallen as snow and this will continue
through the night. Some warm air has crept up the Wenatchee valley
and lead to some freezing rain; an oscillation of snow to mixed
precipitation is possible before it tapers off. A dome of cold air
also lies from the Okanogan valley, across the Waterville Plateau
to the Moses Lake area. So far, surface temperatures and wet bulb
zeros show snow levels right near the surface and could see a
wintry mix of snow, freezing rain and sleet as snow levels
gradually creep to 2k to 2500 feet. East of a line from Ritzville
to Kettle Falls, the warm air has moved into the valleys and
expect a valley rain/mountain snow event overnight. The moderate
rainfall may lead to ponding of water across portions of the
Columbia Basin and Palouse as the ground remains frozen. A cold
front will sweep through the region overnight and allow the
precipitation to taper off from west to east. Expect the
precipitation to linger over north Idaho through the night with
moderate amounts of mountain snow. Overnight lows will be
challenging, but shouldn`t fall too much, lingering near current
dewpoints. Expect no major changes to the current winter
highlights. /rfox.

Saturday through Monday...The active pattern will continue
through the weekend and into the first part of next week as a
series of weather disturbances moves through the region. Then high
pressure will begin to build into the region Monday, but not
before one last weather system sneaks through the region.

Saturday and Saturday night the atmosphere will dry out from west
to east through the day on Saturday and result in a drying trend
with breezy winds through the day. Southwest winds of 15-25 mph
with gusts 35-40 mph will be possible. Temperatures, at least,
will warm into the upper 30s to mid 40s.

Model guidance has been consistent showing the atmosphere
destabilizing Saturday with the trough axis. Lapse rates are
actually quite impressive after 18z across the central and
northern Idaho Panhandle. As weak high pressure builds in behind
the front the surface to mid level flow will become west-
northwest. This puts the focus of the best precipitation to the
northeast zones and the Idaho Panhandle, with a secondary area for
slop over snow showers near the Cascade crest. Showers will likely
back build into the Idaho Palouse and as far east as the Spokane-
Coeur D`Alene area. With the instability that will be present
there will be a good chance for periods of very heavy rain and
snow showers for the central Panhandle and portions of the north
Panhandle. Snow levels will rise to between 2500-3000 ft by the
afternoon, which would mean valley rain and mountain snow.
Additional accumulations of 2-3 inches for the north Panhandle
mountains and 3-5 inches for the central Panhandle mountains will
be very possible. As such we will keep the winter highlights up
for the north Panhandle through Saturday afternoon and for
Shoshone county through Sunday morning.

Precipitation chances will begin to decrease late Saturday night
for the eastern zones, but will be on the increase for the
Cascades as the next quick hitting weather disturbance moves into
the region. The warm front will be on the Cascades by 12z Sunday
with the occlusion following roughly 6 hours later. This will
bring another round of stratiform precipitation to the region.
Model guidance has indicated some moderate to heavy precipitation
with this disturbance as well. Snow levels range from 3500 ft
across the south to 1500 feet or maybe less across the north. So
rain in the valley with mountain snow. At this time 12 hour snow
totals may push snow advisory criteria for the central Panhandle.
There are plenty of highlights out right now for weather in the
short term and we will keep an eye on this to either extend or add
new winter highlights all together. Winds will remain elevated but
should be 5-10 mph weaker on Sunday.

High pressure will slowly build back into the region Sunday night
into Monday. This will result in drier conditions Sunday night and
early Monday. However one weather disturbance will move through
the building ridge late in the day on Monday and bring a last shot
of moisture to the region, at least for this series of storms. /Tobin


Monday night through the day after Thanksgiving: Much better model
agreement today, at least through Wednesday, then there is
a little less agreement thereafter. Yesterday`s outlier of a large
upper level ridge traversing the region midweek is now today`s
consensus. But one last disturbance will bring rain and snow to
the Inland Northwest Monday night into Tuesday. Given the flow
pattern, the Idaho Panhandle and the mountains of northeast
Washington will be affected most, as well as over the Cascade
crest. Enough cold air may be present during the onset that the
valleys may see snow, but increasing snow levels on Tuesday should
switch many of the valleys that are still seeing precipitation to
rain. The ridge builds in Tuesday night and Wednesday, ending any
significant threat for precipitation. This should be good news for
those that will be traveling through the Inland Northwest on
Wednesday. Uncertainty exists on Thanksgiving day and the day
after. It should be an active weather pattern, but no significant
weather systems are expected through Friday. Precipitation chances
were trended toward climatology for the latter two days of the
Holiday week. Temperatures were bumped up some from the previous
forecast, but only by a degree or two. ty

&&

.AVIATION...
18Z TAFS: Cigs and vsbys will improve this morning as the low
levels mix ahead of the advancing warm front from KEAT to KGEG.
VFR conditions will prevail from KPUW to KLWS under light east to
southeast winds. A very moist Pacific storm system will spread
-SN/-RA from the Cascades eastward through the afternoon. Did slow
down the timing slightly with the main precipitation reaching KEAT
after 21z, KMWH 22z and KGEG after 00z. Pcpn will vary btwn -SN,
-RA and -FZRA at KEAT and possibly KMWH and could be moderate at
times. Warmer conditions will bring rain to KGEG/KSFF/KCOE/KPUW/KLWS.
Ceilings with the precipitation are once again expected to drop to
MVFR or even IFR conditions. By Saturday morning, post frontal
westerly winds will increase, although some areas of MVFR
cigs/vsbys will linger. /rfox

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        35  41  30  38  29  37 / 100  20  20  70  30  20
Coeur d`Alene  36  40  31  38  29  37 / 100  50  20  80  50  30
Pullman        37  43  34  40  32  40 / 100  80  50  80  50  20
Lewiston       41  47  37  45  33  44 / 100  70  40  80  50  20
Colville       34  42  24  37  24  37 / 100  20  10  70  30  30
Sandpoint      34  40  30  36  29  37 / 100  70  20  80  50  30
Kellogg        35  38  31  35  31  35 / 100  90  70  80  70  30
Moses Lake     32  46  28  43  30  42 / 100  10  10  30  10  20
Wenatchee      34  43  33  42  32  42 / 100  20  10  40  20  20
Omak           31  41  27  37  26  37 / 100  10  10  30  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

&&

$$






000
FXUS66 KOTX 211911
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1111 AM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring valley rain and
mountain snow to the Cascades this afternoon and spread across
much of the Inland Northwest overnight. Then windy to breezy
conditions with mountain snow showers are expected on Saturday and
Sunday. An active and somewhat wet weather regime will continue
into the next week.


&&

.DISCUSSION...
Due to increased precipitation and winds with the incoming weather
system, deemed it appropriate to let the Air Stagnation Advisory
to expire this morning. Also received reports of freezing rain
near Leavenworth with light snow in Omak. The precipitation band
it pushing east of the crest. /rfox

&&

.AVIATION...
18Z TAFS: Cigs and vsbys will improve this morning as the low
levels mix ahead of the advancing warm front from KEAT to KGEG.
VFR conditions will prevail from KPUW to KLWS under light east to
southeast winds. A very moist Pacific storm system will spread
-SN/-RA from the Cascades eastward through the afternoon. Did slow
down the timing slightly with the main precipitation reaching KEAT
after 21z, KMWH 22z and KGEG after 00z. Pcpn will vary btwn -SN,
-RA and -FZRA at KEAT and possibly KMWH and could be moderate at
times. Warmer conditions will bring rain to KGEG/KSFF/KCOE/KPUW/KLWS.
Ceilings with the precipitation are once again expected to drop to
MVFR or even IFR conditions. By Saturday morning, post frontal
westerly winds will increase, although some areas of MVFR
cigs/vsbys will linger. /rfox


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        37  36  42  30  38  29 /  30 100  20  20  70  30
Coeur d`Alene  38  36  42  31  39  30 /  40 100  50  20  80  50
Pullman        42  37  44  33  41  31 /  10 100  80  50  80  50
Lewiston       46  41  48  36  46  34 /  10 100  70  40  80  50
Colville       36  34  42  23  37  23 /  90 100  20  10  70  30
Sandpoint      34  34  40  29  37  30 /  80 100  70  20  80  50
Kellogg        36  35  39  31  35  31 /  60 100  90  70  80  70
Moses Lake     36  33  47  28  44  29 /  90 100  10  10  30  10
Wenatchee      34  34  45  33  43  31 / 100 100  20  10  40  20
Omak           34  32  42  26  37  27 / 100 100  10  10  30  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

&&

$$





000
FXUS66 KOTX 211911
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1111 AM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring valley rain and
mountain snow to the Cascades this afternoon and spread across
much of the Inland Northwest overnight. Then windy to breezy
conditions with mountain snow showers are expected on Saturday and
Sunday. An active and somewhat wet weather regime will continue
into the next week.


&&

.DISCUSSION...
Due to increased precipitation and winds with the incoming weather
system, deemed it appropriate to let the Air Stagnation Advisory
to expire this morning. Also received reports of freezing rain
near Leavenworth with light snow in Omak. The precipitation band
it pushing east of the crest. /rfox

&&

.AVIATION...
18Z TAFS: Cigs and vsbys will improve this morning as the low
levels mix ahead of the advancing warm front from KEAT to KGEG.
VFR conditions will prevail from KPUW to KLWS under light east to
southeast winds. A very moist Pacific storm system will spread
-SN/-RA from the Cascades eastward through the afternoon. Did slow
down the timing slightly with the main precipitation reaching KEAT
after 21z, KMWH 22z and KGEG after 00z. Pcpn will vary btwn -SN,
-RA and -FZRA at KEAT and possibly KMWH and could be moderate at
times. Warmer conditions will bring rain to KGEG/KSFF/KCOE/KPUW/KLWS.
Ceilings with the precipitation are once again expected to drop to
MVFR or even IFR conditions. By Saturday morning, post frontal
westerly winds will increase, although some areas of MVFR
cigs/vsbys will linger. /rfox


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        37  36  42  30  38  29 /  30 100  20  20  70  30
Coeur d`Alene  38  36  42  31  39  30 /  40 100  50  20  80  50
Pullman        42  37  44  33  41  31 /  10 100  80  50  80  50
Lewiston       46  41  48  36  46  34 /  10 100  70  40  80  50
Colville       36  34  42  23  37  23 /  90 100  20  10  70  30
Sandpoint      34  34  40  29  37  30 /  80 100  70  20  80  50
Kellogg        36  35  39  31  35  31 /  60 100  90  70  80  70
Moses Lake     36  33  47  28  44  29 /  90 100  10  10  30  10
Wenatchee      34  34  45  33  43  31 / 100 100  20  10  40  20
Omak           34  32  42  26  37  27 / 100 100  10  10  30  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

WA...Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

&&

$$






000
FXUS66 KOTX 211756
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
956 AM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring valley rain and
mountain snow to the Cascades this afternoon and spread across
much of the Inland Northwest overnight. Then windy to breezy
conditions with mountain snow showers are expected on Saturday and
Sunday. An active and somewhat wet weather regime will continue
into the next week.

&&

.DISCUSSION...
Made a few updates to the forecast. Patchy fog which was evident
across much of the Columbia Basin to the western Palouse will lift
with the advancing warm front through this morning. Some light
freezing or frozen precipitation is possible in the northern
valleys with increasing isentropic lift through the morning hours.
But the main precipitation band will increase across the Cascades
by midday and gradually spread eastward through the afternoon and
overnight. Based on surface temperatures and temperature profiles,
there is a risk of freezing rain late this afternoon from the
Wenatchee area, across the Waterville Plateau and near Moses Lake.
Otherwise snow will be the main story for much of the Cascades to
the Okanogan Highlands through this evening. /rfox.

&&

.AVIATION...
18Z TAFS: Cigs and vsbys will improve this morning as the low
levels mix ahead of the advancing warm front from KEAT to KGEG.
VFR conditions will prevail from KPUW to KLWS under light east to
southeast winds. A very moist Pacific storm system will spread
-SN/-RA from the Cascades eastward through the afternoon. Did slow
down the timing slightly with the main precipitation reaching KEAT
after 21z, KMWH 22z and KGEG after 00z. Pcpn will vary btwn -SN,
-RA and -FZRA at KEAT and possibly KMWH and could be moderate at
times. Warmer conditions will bring rain to KGEG/KSFF/KCOE/KPUW/KLWS.
Ceilings with the precipitation are once again expected to drop to
MVFR or even IFR conditions. By Saturday morning, post frontal
westerly winds will increase, although some areas of MVFR
cigs/vsbys will linger. /rfox

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        37  36  42  30  38  29 /  30 100  20  20  70  30
Coeur d`Alene  38  36  42  31  39  30 /  40 100  50  20  70  40
Pullman        42  37  44  33  41  31 /  10 100  80  50  70  60
Lewiston       46  41  48  36  46  34 /  10 100  70  30  60  40
Colville       36  34  42  23  37  23 /  90 100  20  10  60  20
Sandpoint      34  34  40  29  37  30 /  80 100  70  30  70  40
Kellogg        36  35  39  31  35  31 /  60 100  90  60  80  60
Moses Lake     36  33  47  28  44  29 /  90 100  10  10  30  10
Wenatchee      34  34  45  33  43  31 / 100 100  20  10  40  20
Omak           34  32  42  26  37  27 / 100 100  10  10  30  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST today for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

     Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

WA...Air Stagnation Advisory until Noon PST today for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

&&

$$





000
FXUS66 KOTX 211756
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
956 AM PST FRI NOV 21 2014

.SYNOPSIS...
A strong and moist Pacific storm will bring valley rain and
mountain snow to the Cascades this afternoon and spread across
much of the Inland Northwest overnight. Then windy to breezy
conditions with mountain snow showers are expected on Saturday and
Sunday. An active and somewhat wet weather regime will continue
into the next week.

&&

.DISCUSSION...
Made a few updates to the forecast. Patchy fog which was evident
across much of the Columbia Basin to the western Palouse will lift
with the advancing warm front through this morning. Some light
freezing or frozen precipitation is possible in the northern
valleys with increasing isentropic lift through the morning hours.
But the main precipitation band will increase across the Cascades
by midday and gradually spread eastward through the afternoon and
overnight. Based on surface temperatures and temperature profiles,
there is a risk of freezing rain late this afternoon from the
Wenatchee area, across the Waterville Plateau and near Moses Lake.
Otherwise snow will be the main story for much of the Cascades to
the Okanogan Highlands through this evening. /rfox.

&&

.AVIATION...
18Z TAFS: Cigs and vsbys will improve this morning as the low
levels mix ahead of the advancing warm front from KEAT to KGEG.
VFR conditions will prevail from KPUW to KLWS under light east to
southeast winds. A very moist Pacific storm system will spread
-SN/-RA from the Cascades eastward through the afternoon. Did slow
down the timing slightly with the main precipitation reaching KEAT
after 21z, KMWH 22z and KGEG after 00z. Pcpn will vary btwn -SN,
-RA and -FZRA at KEAT and possibly KMWH and could be moderate at
times. Warmer conditions will bring rain to KGEG/KSFF/KCOE/KPUW/KLWS.
Ceilings with the precipitation are once again expected to drop to
MVFR or even IFR conditions. By Saturday morning, post frontal
westerly winds will increase, although some areas of MVFR
cigs/vsbys will linger. /rfox

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        37  36  42  30  38  29 /  30 100  20  20  70  30
Coeur d`Alene  38  36  42  31  39  30 /  40 100  50  20  70  40
Pullman        42  37  44  33  41  31 /  10 100  80  50  70  60
Lewiston       46  41  48  36  46  34 /  10 100  70  30  60  40
Colville       36  34  42  23  37  23 /  90 100  20  10  60  20
Sandpoint      34  34  40  29  37  30 /  80 100  70  30  70  40
Kellogg        36  35  39  31  35  31 /  60 100  90  60  80  60
Moses Lake     36  33  47  28  44  29 /  90 100  10  10  30  10
Wenatchee      34  34  45  33  43  31 / 100 100  20  10  40  20
Omak           34  32  42  26  37  27 / 100 100  10  10  30  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST today for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning until 6 PM PST Saturday for Northern
     Panhandle.

     Winter Storm Warning until 6 AM PST Sunday for Central Panhandle
     Mountains.

WA...Air Stagnation Advisory until Noon PST today for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning until 6 AM PST Saturday for East Slopes
     Northern Cascades-Okanogan Highlands-Okanogan Valley-
     Waterville Plateau.

     Winter Storm Warning until 6 PM PST Saturday for Northeast
     Mountains.

     Winter Weather Advisory until 6 AM PST Saturday for Wenatchee
     Area.

&&

$$






000
FXUS66 KOTX 211231
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
431 AM PST FRI NOV 21 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.

&&

.DISCUSSION...
..BIGGEST SNOW MAKER SO FAR THIS  SEASON TO HIT MUCH OF THE INLAND
NORTHWEST LATER TODAY THROUGH SATURDAY...

Today and tonight ...Right now is the calm before the storm over
the Inland Northwest. All the region will see this morning is
some light precipitation in advance of a much wetter system
scheduled to move in later today. The 285k isentropic surface
continues to depict a fairly steep north-south pressure profile.
And this will become increasingly important this morning...as the
flow back toward more of a southerly orientation. This should make
light precipitation a little more widespread this
morning...especially over the northern third of Washington and the
northern half of the Idaho Panhandle. What makes this situation a
little more difficult than usual is the key dendritic layer will
be far from saturated. In fact only the layer from -10 to -15c
will have any moisture that nears saturation. This could lead to
periods of light freezing drizzle across the northern valleys in
addition to periodic snow. Amounts will be fairly light. By later
this morning though...the precipitation trends will begin to
increase steadily.

This precipitation increase will result from a good influx of
sub-tropical moisture. As of 2am...water vapor imagery was showing
a deep atmospheric river extending from west of Hawaii almost to
the Washington coast. This plume is expected to surge over the
Cascades by afternoon and remain over the region through much of
the night as a warm front invades the region. The front will
contribute to the warming temperatures over most valley locations.
The exception will be in the lee of the Cascades due to cold air
damming. The damming is expected to hold cold air over the
Waterville Plateau...Okanogan Valley...Wenatchee area...and
Cascade Valleys. Most of these locations still look like they will
see snow throughout the event. Models are fairly consistent on
dropping anywhere from .60-1.20 inches near the Cascades between
now and Saturday morning with values from .30-.80 inches across
most of the Inland Northwest. The combination of cold air and
heavy precipitation equates to a very good chance of heavy snow.
Valleys in the Cascades could see anywhere from 5-10 inches of
snow...with heavier amounts over the mountains...especially near
the crest. From Wenatchee to the Okanogan valleys...snow amount
should generally range from 3 to 6 inches...however that`s
assuming all the precipitation falls as snow. That notion is far
from a slam dunk for Wenatchee...the Wenatchee River Valley...and
Waterville Plateau...as there are signs that a fairly small
elevated melting layer will push into this area late this
afternoon or this evening. This would either put a strong damper
on the production of snow...or lead to a period of freezing rain.
The SREF would hedge toward the latter. This is far from a
confident notion as there are significant model differences. The
NAM would move this wedge over these areas almost at the onset of
the event...whereas the EC and GFS hold off until late this
evening. Not sure which model to believe...however the NAM may be
onto something as its handling surface temperatures much better
compared to surface observations. There is a much lesser chance of
this warm wedge moving as far north as Lake Chelan or the Okanogan
Valley. Elsewhere...the event looks primarily like a rain
maker...with snow levels gradually climbing to 3-4k feet over
northeast Washington and the north Idaho Panhandle...and anywhere
from 4-5k feet over the central Panhandle. There will likely be a
transition from snow to rain in the surrounding valleys...with 1
to 3 inches of snow a distinct possibility. Locally heavier
amounts are possible in valley locations close to the Canadian
border including Bonners Ferry...Metaline Falls and Laurier. The
widespread stratiform precipitation associated with the warm front
will transition to an unstable regime with the passage of a
significant shortwave trough and associated cold front. The front
should pass through the Cascades overnight and into the Idaho
Panhandle by early morning.

The front will finally provide the focus for mixing out all the
valleys with moderate to locally strong winds associated with good
downward momentum per cold air advection. Enough moisture and
instability will remain in place for numerous snow showers
primarily over the Idaho Panhandle and near the Cascades crest.
Meanwhile the lee valleys of the Cascades...Columbia Basin...and
the Spokane area will see a drying trend. It`s interesting to note
that with the passage of the cold front we will see a good
atmospheric destabilization and the NAM is actually showing some
small CAPE values over the central Panhandle by afternoon and
evening. This suggests we could see a significant development of
post frontal showers accompanied by locally heavy snow rates.
Elsewhere the main issue will be winds. Looks like the area could
see speeds approach wind advisory levels with sustained speeds of
20-25 mph with gusts of 40 mph possible. The strongest winds are
expected over the southeast Columbia Basin and Palouse. Based on
the myriad of highlights out at this time...we will defer this
issue to future shifts...but will give mention in hazardous
weather outlook. The strong winds will mix out any semblance of
modified arctic air...resulting in warming temps. However when
factoring in the winds...it certainly won`t feel warmer. fx

Saturday night through Tuesday night: A parade of systems will
in the northwest flow will bring precipitation every other day or
so. This comes with the potential for an extended period of wet
weather starting Monday night or Tuesday, accompanied by milder
and perhaps slightly above seasonal normal temperatures. However
model agreement falters by this time frame and forecast confidence
is degraded.

Saturday night one system pulls east. This and the northwest flow
will keep the threat of snow alive across the Panhandle and
southeast WA through evening. Chances will wane overnight as the
system exits. At the same time the lingering threat of snow near
the Cascade crest in the onshore flow will be bolstered by the
moisture and lift increasing with the next warm front overnight.
Meanwhile the remainder of central and eastern WA will continue to
be plagued by low clouds, as well as a threat of patchy fog.

Sunday the warm front moves into eastern WA and north ID,
bringing the next round of snow and rain. Models have sped up the
start of precipitation for the morning, at least slightly. By
afternoon the trailing occluded front comes into central WA,
lessening the precipitation in the lee of the Cascades and western
Basin. Yet east of here the threat will remain high through
evening, due to the passing occluded front, a lingering theta-e
ridge that weakens near the ID/WA border and the northwest flow.
Within this region models place the higher precipitation amounts
over southeast WA through the central Panhandle. The threat
appears to gradually wane overnight as the feature weakens.

As for precipitation-type and amounts: in the morning snow will
be the predominate threat. Exceptions will be over the deeper
Columbia Basin and L-C Valley where rain will be more likely. By
afternoon the main snow threat backs into the Cascades and lifts
toward the northern WA and ID Panhandle mountains, while mainly
rain or a rain/snow mix will be more likely over the Columbia
Basin eastward to the lower elevations of the Panhandle. As
compared to Friday`s system, the lift is weaker and the moisture
tap is not as impressive. So precipitation amounts look lower. Yet
with that said they are still modest in some areas. While models
generally depict less than a tenth toward the lee of the Cascades
and western Basin, they show between a tenth and a quarter of inch
over the eastern Basin. Near half an inch is depicted in the
eastern mountains and near an inch near the Cascade crest. Falling
as snow this could result in more moderate to locally heavy snow
amounts around the mountains. Yet even the lower elevations could
see some accumulations; early total suggest maybe a half inch to
an inch, with local amounts near two in some of the northern
mountain valleys.

Between Monday and Tuesday the next weather maker arrives. There
are still some questions about the evolution of the system,
including precipitation amounts and type. Yet it has the potential
to be a wet and milder period. By Monday afternoon and evening the
next warm front lifts across the region. The associated surface
low tracks from the central BC coast Monday morning to northeast
MT Tuesday morning. However models do not indicate a strong push
from the north behind that low. This is due to yet another system
moving across the Gulf of Alaska into western BC by Tuesday, which
should stalling things. This latter feature keeps a quasi-
stationary front across northeast WA through the central Panhandle
Monday night into Tuesday. Furthermore models show at least two
smaller-scale low pressure centers moves along that stalled front,
a relatively weak one Tuesday morning and a stronger low pressure
center late Tuesday into Tuesday night. Furthermore models show
another good subtropical moisture tap. PWATs rise to between 0.50
and 0.85 inches by Tuesday (or between 130 to 225% of normal).

So this evolution suggests another round of precipitation. Its
precise evolution may easily change. Yet right now models suggest
precipitation developing first around the Cascades and northern
mountains Monday (albeit light), before expanding across the
eastern third of WA and the ID Panhandle Monday night into Tuesday
morning. Chances remain high into Tuesday night with precipitation
rates on the rise, especially if models continue to depict that
stronger low moving along the stalled front. There are caveats to
this high precipitation threat. In the continued west-northwest
flow models paint the highest precipitation amounts across the
Cascade crest and across the Idaho Panhandle, save for the places
like the L-C Valley. Yet in the lee of the Cascades and western
Basin the west-northwest flow may provide enough to keep things
drier, due to the downsloping/shadow effect, at least for at least
a portion of this period. The best threat of precipitation in the
region may come around Tuesday afternoon into Tuesday evening,
when that second strong low moves along that stall boundary. In
addition if the stalled boundary remains further north, then the
precipitation threat may be diminished away from the all but the
Cascades and northern mountains.

As for precipitation-type during this time frame: snow levels
look to be on the rise. Initially models keep colder air in place.
Snow levels are currently projected to be around 1500 to 3500
feet, lowest toward NE WA and north ID. However all models show
the jet stream lifting north and miler air surging in. Monday
night into Tuesday morning models show snow level rise to between
5000 and 8000 feet across the Cascades through southeast WA,
though they linger near 2500 to 4000 feet across northeast WA and
the ID Panhandle. Going into Tuesday afternoon and night models
push snow levels up to between 7000 to 8000 feet over much of the
region, with the main sticky point at this time toward the
Canadian border where some still keep them at low as 3000 feet. So
these will continue to be fine-tuned, I`m sure. Overall this means
the potential for snow early Monday, changes to primarily rain
Monday night into Tuesday, save for the potential for snow to
linger longer at lower elevations northern counties where
confidence is lower. /J. Cote`

Wednesday through Friday: While many are planning for a busy
Thanksgiving travel period, the forecast continues to hinder the
planning process as it remains up in the air at this point with
lots of uncertainty. Just as models started to come into some sort
of agreement earlier today, the latest ECMWF jumped off the deep
end depicting what the GFS was showing several runs ago. While the
latest Euro now shows a fair amount of ridging on the west coast
leading to warmer and drier conditions, the GFS continues to
bring cooler northwesterly flow onshore keeping temps a bit cooler
and the pattern a bit more active. Due to the large amount of
inconsistencies in model comparison and run to run evaluation,
very few changes were made to the forecast as it could have hurt
more than helped at this point. The main change was to raise
temperatures and in turn snow levels as well to values above most
valley floors throughout the extended leading to any precipitation
to fall as valley rain and mountain snow. Both the GFS and ECMWF
had wet bulb zero temps depicted much further north than
previously shown so the mentioned changes were made. POPs were
left essentially untouched and we will hope for considerable
improvements in model consistency in the near future to get a
better sense of what we can expect for the holiday period.
/Fliehman

&&

.AVIATION...
12Z TAFS: MVFR Ceilings and vis continues to be common over the
region this morning as a moist boundary layer and light winds
exists under a strong low level inversion...with a mix of MVFR to
LIFR conditions at the northern and western TAF sites. Downsloping
winds at KPUW and KLWS will keep them in the VFR category. A very
moist Pacific storm system will spread thickening clouds over the
region on Friday with -SN/-RA to develop aft 19z in KEAT and aft
23z at KGEG eastward. Pcpn will vary btwn -SN, -RA and -FZRA at
KEAT and could be moderate at times. Warmer conditions will bring
rain to KMWH/KGEG/KSFF/KCOE/KPUW/KLWS. Ceilings with the
precipitation are once again expected to drop to MVFR or even IFR
conditions. /Fliehman





&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        37  36  42  30  38  29 /  30 100  20  20  70  30
Coeur d`Alene  38  36  42  31  39  30 /  40 100  50  20  70  40
Pullman        42  37  44  33  41  31 /  10 100  70  50  70  60
Lewiston       46  41  48  36  46  34 /  10 100  60  30  60  40
Colville       36  34  42  23  37  23 /  90 100  20  10  60  20
Sandpoint      34  34  40  29  37  30 /  80 100  70  30  70  40
Kellogg        36  35  39  31  35  31 /  60 100  80  60  80  60
Moses Lake     36  33  47  28  44  29 /  90 100  10  10  30  10
Wenatchee      34  34  45  33  43  31 / 100 100  10  10  40  20
Omak           34  32  42  26  37  27 / 100 100  10  10  30  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST today for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon today to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon today to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST today for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon today to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon today to 6 PM PST Saturday for
     Northeast Mountains.

     Winter Weather Advisory from Noon today to 6 AM PST Saturday for
     Wenatchee Area.

&&

$$





000
FXUS66 KOTX 211231
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
431 AM PST FRI NOV 21 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.

&&

.DISCUSSION...
..BIGGEST SNOW MAKER SO FAR THIS  SEASON TO HIT MUCH OF THE INLAND
NORTHWEST LATER TODAY THROUGH SATURDAY...

Today and tonight ...Right now is the calm before the storm over
the Inland Northwest. All the region will see this morning is
some light precipitation in advance of a much wetter system
scheduled to move in later today. The 285k isentropic surface
continues to depict a fairly steep north-south pressure profile.
And this will become increasingly important this morning...as the
flow back toward more of a southerly orientation. This should make
light precipitation a little more widespread this
morning...especially over the northern third of Washington and the
northern half of the Idaho Panhandle. What makes this situation a
little more difficult than usual is the key dendritic layer will
be far from saturated. In fact only the layer from -10 to -15c
will have any moisture that nears saturation. This could lead to
periods of light freezing drizzle across the northern valleys in
addition to periodic snow. Amounts will be fairly light. By later
this morning though...the precipitation trends will begin to
increase steadily.

This precipitation increase will result from a good influx of
sub-tropical moisture. As of 2am...water vapor imagery was showing
a deep atmospheric river extending from west of Hawaii almost to
the Washington coast. This plume is expected to surge over the
Cascades by afternoon and remain over the region through much of
the night as a warm front invades the region. The front will
contribute to the warming temperatures over most valley locations.
The exception will be in the lee of the Cascades due to cold air
damming. The damming is expected to hold cold air over the
Waterville Plateau...Okanogan Valley...Wenatchee area...and
Cascade Valleys. Most of these locations still look like they will
see snow throughout the event. Models are fairly consistent on
dropping anywhere from .60-1.20 inches near the Cascades between
now and Saturday morning with values from .30-.80 inches across
most of the Inland Northwest. The combination of cold air and
heavy precipitation equates to a very good chance of heavy snow.
Valleys in the Cascades could see anywhere from 5-10 inches of
snow...with heavier amounts over the mountains...especially near
the crest. From Wenatchee to the Okanogan valleys...snow amount
should generally range from 3 to 6 inches...however that`s
assuming all the precipitation falls as snow. That notion is far
from a slam dunk for Wenatchee...the Wenatchee River Valley...and
Waterville Plateau...as there are signs that a fairly small
elevated melting layer will push into this area late this
afternoon or this evening. This would either put a strong damper
on the production of snow...or lead to a period of freezing rain.
The SREF would hedge toward the latter. This is far from a
confident notion as there are significant model differences. The
NAM would move this wedge over these areas almost at the onset of
the event...whereas the EC and GFS hold off until late this
evening. Not sure which model to believe...however the NAM may be
onto something as its handling surface temperatures much better
compared to surface observations. There is a much lesser chance of
this warm wedge moving as far north as Lake Chelan or the Okanogan
Valley. Elsewhere...the event looks primarily like a rain
maker...with snow levels gradually climbing to 3-4k feet over
northeast Washington and the north Idaho Panhandle...and anywhere
from 4-5k feet over the central Panhandle. There will likely be a
transition from snow to rain in the surrounding valleys...with 1
to 3 inches of snow a distinct possibility. Locally heavier
amounts are possible in valley locations close to the Canadian
border including Bonners Ferry...Metaline Falls and Laurier. The
widespread stratiform precipitation associated with the warm front
will transition to an unstable regime with the passage of a
significant shortwave trough and associated cold front. The front
should pass through the Cascades overnight and into the Idaho
Panhandle by early morning.

The front will finally provide the focus for mixing out all the
valleys with moderate to locally strong winds associated with good
downward momentum per cold air advection. Enough moisture and
instability will remain in place for numerous snow showers
primarily over the Idaho Panhandle and near the Cascades crest.
Meanwhile the lee valleys of the Cascades...Columbia Basin...and
the Spokane area will see a drying trend. It`s interesting to note
that with the passage of the cold front we will see a good
atmospheric destabilization and the NAM is actually showing some
small CAPE values over the central Panhandle by afternoon and
evening. This suggests we could see a significant development of
post frontal showers accompanied by locally heavy snow rates.
Elsewhere the main issue will be winds. Looks like the area could
see speeds approach wind advisory levels with sustained speeds of
20-25 mph with gusts of 40 mph possible. The strongest winds are
expected over the southeast Columbia Basin and Palouse. Based on
the myriad of highlights out at this time...we will defer this
issue to future shifts...but will give mention in hazardous
weather outlook. The strong winds will mix out any semblance of
modified arctic air...resulting in warming temps. However when
factoring in the winds...it certainly won`t feel warmer. fx

Saturday night through Tuesday night: A parade of systems will
in the northwest flow will bring precipitation every other day or
so. This comes with the potential for an extended period of wet
weather starting Monday night or Tuesday, accompanied by milder
and perhaps slightly above seasonal normal temperatures. However
model agreement falters by this time frame and forecast confidence
is degraded.

Saturday night one system pulls east. This and the northwest flow
will keep the threat of snow alive across the Panhandle and
southeast WA through evening. Chances will wane overnight as the
system exits. At the same time the lingering threat of snow near
the Cascade crest in the onshore flow will be bolstered by the
moisture and lift increasing with the next warm front overnight.
Meanwhile the remainder of central and eastern WA will continue to
be plagued by low clouds, as well as a threat of patchy fog.

Sunday the warm front moves into eastern WA and north ID,
bringing the next round of snow and rain. Models have sped up the
start of precipitation for the morning, at least slightly. By
afternoon the trailing occluded front comes into central WA,
lessening the precipitation in the lee of the Cascades and western
Basin. Yet east of here the threat will remain high through
evening, due to the passing occluded front, a lingering theta-e
ridge that weakens near the ID/WA border and the northwest flow.
Within this region models place the higher precipitation amounts
over southeast WA through the central Panhandle. The threat
appears to gradually wane overnight as the feature weakens.

As for precipitation-type and amounts: in the morning snow will
be the predominate threat. Exceptions will be over the deeper
Columbia Basin and L-C Valley where rain will be more likely. By
afternoon the main snow threat backs into the Cascades and lifts
toward the northern WA and ID Panhandle mountains, while mainly
rain or a rain/snow mix will be more likely over the Columbia
Basin eastward to the lower elevations of the Panhandle. As
compared to Friday`s system, the lift is weaker and the moisture
tap is not as impressive. So precipitation amounts look lower. Yet
with that said they are still modest in some areas. While models
generally depict less than a tenth toward the lee of the Cascades
and western Basin, they show between a tenth and a quarter of inch
over the eastern Basin. Near half an inch is depicted in the
eastern mountains and near an inch near the Cascade crest. Falling
as snow this could result in more moderate to locally heavy snow
amounts around the mountains. Yet even the lower elevations could
see some accumulations; early total suggest maybe a half inch to
an inch, with local amounts near two in some of the northern
mountain valleys.

Between Monday and Tuesday the next weather maker arrives. There
are still some questions about the evolution of the system,
including precipitation amounts and type. Yet it has the potential
to be a wet and milder period. By Monday afternoon and evening the
next warm front lifts across the region. The associated surface
low tracks from the central BC coast Monday morning to northeast
MT Tuesday morning. However models do not indicate a strong push
from the north behind that low. This is due to yet another system
moving across the Gulf of Alaska into western BC by Tuesday, which
should stalling things. This latter feature keeps a quasi-
stationary front across northeast WA through the central Panhandle
Monday night into Tuesday. Furthermore models show at least two
smaller-scale low pressure centers moves along that stalled front,
a relatively weak one Tuesday morning and a stronger low pressure
center late Tuesday into Tuesday night. Furthermore models show
another good subtropical moisture tap. PWATs rise to between 0.50
and 0.85 inches by Tuesday (or between 130 to 225% of normal).

So this evolution suggests another round of precipitation. Its
precise evolution may easily change. Yet right now models suggest
precipitation developing first around the Cascades and northern
mountains Monday (albeit light), before expanding across the
eastern third of WA and the ID Panhandle Monday night into Tuesday
morning. Chances remain high into Tuesday night with precipitation
rates on the rise, especially if models continue to depict that
stronger low moving along the stalled front. There are caveats to
this high precipitation threat. In the continued west-northwest
flow models paint the highest precipitation amounts across the
Cascade crest and across the Idaho Panhandle, save for the places
like the L-C Valley. Yet in the lee of the Cascades and western
Basin the west-northwest flow may provide enough to keep things
drier, due to the downsloping/shadow effect, at least for at least
a portion of this period. The best threat of precipitation in the
region may come around Tuesday afternoon into Tuesday evening,
when that second strong low moves along that stall boundary. In
addition if the stalled boundary remains further north, then the
precipitation threat may be diminished away from the all but the
Cascades and northern mountains.

As for precipitation-type during this time frame: snow levels
look to be on the rise. Initially models keep colder air in place.
Snow levels are currently projected to be around 1500 to 3500
feet, lowest toward NE WA and north ID. However all models show
the jet stream lifting north and miler air surging in. Monday
night into Tuesday morning models show snow level rise to between
5000 and 8000 feet across the Cascades through southeast WA,
though they linger near 2500 to 4000 feet across northeast WA and
the ID Panhandle. Going into Tuesday afternoon and night models
push snow levels up to between 7000 to 8000 feet over much of the
region, with the main sticky point at this time toward the
Canadian border where some still keep them at low as 3000 feet. So
these will continue to be fine-tuned, I`m sure. Overall this means
the potential for snow early Monday, changes to primarily rain
Monday night into Tuesday, save for the potential for snow to
linger longer at lower elevations northern counties where
confidence is lower. /J. Cote`

Wednesday through Friday: While many are planning for a busy
Thanksgiving travel period, the forecast continues to hinder the
planning process as it remains up in the air at this point with
lots of uncertainty. Just as models started to come into some sort
of agreement earlier today, the latest ECMWF jumped off the deep
end depicting what the GFS was showing several runs ago. While the
latest Euro now shows a fair amount of ridging on the west coast
leading to warmer and drier conditions, the GFS continues to
bring cooler northwesterly flow onshore keeping temps a bit cooler
and the pattern a bit more active. Due to the large amount of
inconsistencies in model comparison and run to run evaluation,
very few changes were made to the forecast as it could have hurt
more than helped at this point. The main change was to raise
temperatures and in turn snow levels as well to values above most
valley floors throughout the extended leading to any precipitation
to fall as valley rain and mountain snow. Both the GFS and ECMWF
had wet bulb zero temps depicted much further north than
previously shown so the mentioned changes were made. POPs were
left essentially untouched and we will hope for considerable
improvements in model consistency in the near future to get a
better sense of what we can expect for the holiday period.
/Fliehman

&&

.AVIATION...
12Z TAFS: MVFR Ceilings and vis continues to be common over the
region this morning as a moist boundary layer and light winds
exists under a strong low level inversion...with a mix of MVFR to
LIFR conditions at the northern and western TAF sites. Downsloping
winds at KPUW and KLWS will keep them in the VFR category. A very
moist Pacific storm system will spread thickening clouds over the
region on Friday with -SN/-RA to develop aft 19z in KEAT and aft
23z at KGEG eastward. Pcpn will vary btwn -SN, -RA and -FZRA at
KEAT and could be moderate at times. Warmer conditions will bring
rain to KMWH/KGEG/KSFF/KCOE/KPUW/KLWS. Ceilings with the
precipitation are once again expected to drop to MVFR or even IFR
conditions. /Fliehman





&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        37  36  42  30  38  29 /  30 100  20  20  70  30
Coeur d`Alene  38  36  42  31  39  30 /  40 100  50  20  70  40
Pullman        42  37  44  33  41  31 /  10 100  70  50  70  60
Lewiston       46  41  48  36  46  34 /  10 100  60  30  60  40
Colville       36  34  42  23  37  23 /  90 100  20  10  60  20
Sandpoint      34  34  40  29  37  30 /  80 100  70  30  70  40
Kellogg        36  35  39  31  35  31 /  60 100  80  60  80  60
Moses Lake     36  33  47  28  44  29 /  90 100  10  10  30  10
Wenatchee      34  34  45  33  43  31 / 100 100  10  10  40  20
Omak           34  32  42  26  37  27 / 100 100  10  10  30  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST today for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon today to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon today to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST today for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon today to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon today to 6 PM PST Saturday for
     Northeast Mountains.

     Winter Weather Advisory from Noon today to 6 AM PST Saturday for
     Wenatchee Area.

&&

$$






000
FXUS66 KOTX 211128
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
328 AM PST FRI NOV 21 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.

&&

.DISCUSSION...
..BIGGEST SNOW MAKER SO FAR THIS  SEASON TO HIT MUCH OF THE INLAND
NORTHWEST LATER TODAY THROUGH SATURDAY...

Today and tonight ...Right now is the calm before the storm over
the Inland Northwest. All the region will see this morning is
some light precipitation in advance of a much wetter system
scheduled to move in later today. The 285k isentropic surface
continues to depict a fairly steep north-south pressure profile.
And this will become increasingly important this morning...as the
flow back toward more of a southerly orientation. This should make
light precipitation a little more widespread this
morning...especially over the northern third of Washington and the
northern half of the Idaho Panhandle. What makes this situation a
little more difficult than usual is the key dendritic layer will
be far from saturated. In fact only the layer from -10 to -15c
will have any moisture that nears saturation. This could lead to
periods of light freezing drizzle across the northern valleys in
addition to periodic snow. Amounts will be fairly light. By later
this morning though...the precipitation trends will begin to
increase steadily.

This precipitation increase will result from a good influx of
sub-tropical moisture. As of 2am...water vapor imagery was showing
a deep atmospheric river extending from west of Hawaii almost to
the Washington coast. This plume is expected to surge over the
Cascades by afternoon and remain over the region through much of
the night as a warm front invades the region. The front will
contribute to the warming temperatures over most valley locations.
The exception will be in the lee of the Cascades due to cold air
damming. The damming is expected to hold cold air over the
Waterville Plateau...Okanogan Valley...Wenatchee area...and
Cascade Valleys. Most of these locations still look like they will
see snow throughout the event. Models are fairly consistent on
dropping anywhere from .60-1.20 inches near the Cascades between
now and Saturday morning with values from .30-.80 inches across
most of the Inland Northwest. The combination of cold air and
heavy precipitation equates to a very good chance of heavy snow.
Valleys in the Cascades could see anywhere from 5-10 inches of
snow...with heavier amounts over the mountains...especially near
the crest. From Wenatchee to the Okanogan valleys...snow amount
should generally range from 3 to 6 inches...however that`s
assuming all the precipitation falls as snow. That notion is far
from a slam dunk for Wenatchee...the Wenatchee River Valley...and
Waterville Plateau...as there are signs that a fairly small
elevated melting layer will push into this area late this
afternoon or this evening. This would either put a strong damper
on the production of snow...or lead to a period of freezing rain.
The SREF would hedge toward the latter. This is far from a
confident notion as there are significant model differences. The
NAM would move this wedge over these areas almost at the onset of
the event...whereas the EC and GFS hold off until late this
evening. Not sure which model to believe...however the NAM may be
onto something as its handling surface temperatures much better
compared to surface observations. There is a much lesser chance of
this warm wedge moving as far north as Lake Chelan or the Okanogan
Valley. Elsewhere...the event looks primarily like a rain
maker...with snow levels gradually climbing to 3-4k feet over
northeast Washington and the north Idaho Panhandle...and anywhere
from 4-5k feet over the central Panhandle. There will likely be a
transition from snow to rain in the surrounding valleys...with 1
to 3 inches of snow a distinct possibility. Locally heavier
amounts are possible in valley locations close to the Canadian
border including Bonners Ferry...Metaline Falls and Laurier. The
widespread stratiform precipitation associated with the warm front
will transition to an unstable regime with the passage of a
significant shortwave trough and associated cold front. The front
should pass through the Cascades overnight and into the Idaho
Panhandle by early morning.

The front will finally provide the focus for mixing out all the
valleys with moderate to locally strong winds associated with good
downward momentum per cold air advection. Enough moisture and
instability will remain in place for numerous snow showers
primarily over the Idaho Panhandle and near the Cascades crest.
Meanwhile the lee valleys of the Cascades...Columbia Basin...and
the Spokane area will see a drying trend. It`s interesting to note
that with the passage of the cold front we will see a good
atmospheric destabilization and the NAM is actually showing some
small CAPE values over the central Panhandle by afternoon and
evening. This suggests we could see a significant development of
post frontal showers accompanied by locally heavy snow rates.
Elsewhere the main issue will be winds. Looks like the area could
see speeds approach wind advisory levels with sustained speeds of
20-25 mph with gusts of 40 mph possible. The strongest winds are
expected over the southeast Columbia Basin and Palouse. Based on
the myriad of highlights out at this time...we will defer this
issue to future shifts...but will give mention in hazardous
weather outlook. The strong winds will mix out any semblance of
modified arctic air...resulting in warming temps. However when
factoring in the winds...it certainly won`t feel warmer. fx

Saturday night through Tuesday night: A parade of systems will
in the northwest flow will bring precipitation every other day or
so. This comes with the potential for an extended period of wet
weather starting Monday night or Tuesday, accompanied by milder
and perhaps slightly above seasonal normal temperatures. However
model agreement falters by this time frame and forecast confidence
is degraded.

Saturday night one system pulls east. This and the northwest flow
will keep the threat of snow alive across the Panhandle and
southeast WA through evening. Chances will wane overnight as the
system exits. At the same time the lingering threat of snow near
the Cascade crest in the onshore flow will be bolstered by the
moisture and lift increasing with the next warm front overnight.
Meanwhile the remainder of central and eastern WA will continue to
be plagued by low clouds, as well as a threat of patchy fog.

Sunday the warm front moves into eastern WA and north ID,
bringing the next round of snow and rain. Models have sped up the
start of precipitation for the morning, at least slightly. By
afternoon the trailing occluded front comes into central WA,
lessening the precipitation in the lee of the Cascades and western
Basin. Yet east of here the threat will remain high through
evening, due to the passing occluded front, a lingering theta-e
ridge that weakens near the ID/WA border and the northwest flow.
Within this region models place the higher precipitation amounts
over southeast WA through the central Panhandle. The threat
appears to gradually wane overnight as the feature weakens.

As for precipitation-type and amounts: in the morning snow will
be the predominate threat. Exceptions will be over the deeper
Columbia Basin and L-C Valley where rain will be more likely. By
afternoon the main snow threat backs into the Cascades and lifts
toward the northern WA and ID Panhandle mountains, while mainly
rain or a rain/snow mix will be more likely over the Columbia
Basin eastward to the lower elevations of the Panhandle. As
compared to Friday`s system, the lift is weaker and the moisture
tap is not as impressive. So precipitation amounts look lower. Yet
with that said they are still modest in some areas. While models
generally depict less than a tenth toward the lee of the Cascades
and western Basin, they show between a tenth and a quarter of inch
over the eastern Basin. Near half an inch is depicted in the
eastern mountains and near an inch near the Cascade crest. Falling
as snow this could result in more moderate to locally heavy snow
amounts around the mountains. Yet even the lower elevations could
see some accumulations; early total suggest maybe a half inch to
an inch, with local amounts near two in some of the northern
mountain valleys.

Between Monday and Tuesday the next weather maker arrives. There
are still some questions about the evolution of the system,
including precipitation amounts and type. Yet it has the potential
to be a wet and milder period. By Monday afternoon and evening the
next warm front lifts across the region. The associated surface
low tracks from the central BC coast Monday morning to northeast
MT Tuesday morning. However models do not indicate a strong push
from the north behind that low. This is due to yet another system
moving across the Gulf of Alaska into western BC by Tuesday, which
should stalling things. This latter feature keeps a quasi-
stationary front across northeast WA through the central Panhandle
Monday night into Tuesday. Furthermore models show at least two
smaller-scale low pressure centers moves along that stalled front,
a relatively weak one Tuesday morning and a stronger low pressure
center late Tuesday into Tuesday night. Furthermore models show
another good subtropical moisture tap. PWATs rise to between 0.50
and 0.85 inches by Tuesday (or between 130 to 225% of normal).

So this evolution suggests another round of precipitation. Its
precise evolution may easily change. Yet right now models suggest
precipitation developing first around the Cascades and northern
mountains Monday (albeit light), before expanding across the
eastern third of WA and the ID Panhandle Monday night into Tuesday
morning. Chances remain high into Tuesday night with precipitation
rates on the rise, especially if models continue to depict that
stronger low moving along the stalled front. There are caveats to
this high precipitation threat. In the continued west-northwest
flow models paint the highest precipitation amounts across the
Cascade crest and across the Idaho Panhandle, save for the places
like the L-C Valley. Yet in the lee of the Cascades and western
Basin the west-northwest flow may provide enough to keep things
drier, due to the downsloping/shadow effect, at least for at least
a portion of this period. The best threat of precipitation in the
region may come around Tuesday afternoon into Tuesday evening,
when that second strong low moves along that stall boundary. In
addition if the stalled boundary remains further north, then the
precipitation threat may be diminished away from the all but the
Cascades and northern mountains.

As for precipitation-type during this time frame: snow levels
look to be on the rise. Initially models keep colder air in place.
Snow levels are currently projected to be around 1500 to 3500
feet, lowest toward NE WA and north ID. However all models show
the jet stream lifting north and miler air surging in. Monday
night into Tuesday morning models show snow level rise to between
5000 and 8000 feet across the Cascades through southeast WA,
though they linger near 2500 to 4000 feet across northeast WA and
the ID Panhandle. Going into Tuesday afternoon and night models
push snow levels up to between 7000 to 8000 feet over much of the
region, with the main sticky point at this time toward the
Canadian border where some still keep them at low as 3000 feet. So
these will continue to be fine-tuned, I`m sure. Overall this means
the potential for snow early Monday, changes to primarily rain
Monday night into Tuesday, save for the potential for snow to
linger longer at lower elevations northern counties where
confidence is lower. /J. Cote`

Wednesday through Friday: While many are planning for a busy
Thanksgiving travel period, the forecast continues to hinder the
planning process as it remains up in the air at this point with
lots of uncertainty. Just as models started to come into some sort
of agreement earlier today, the latest ECMWF jumped off the deep
end depicting what the GFS was showing several runs ago. While the
latest Euro now shows a fair amount of ridging on the west coast
leading to warmer and drier conditions, the GFS continues to
bring cooler northwesterly flow onshore keeping temps a bit cooler
and the pattern a bit more active. Due to the large amount of
inconsistencies in model comparison and run to run evaluation,
very few changes were made to the forecast as it could have hurt
more than helped at this point. The main change was to raise
temperatures and in turn snow levels as well to values above most
valley floors throughout the extended leading to any precipitation
to fall as valley rain and mountain snow. Both the GFS and ECMWF
had wet bulb zero temps depicted much further north than
previously shown so the mentioned changes were made. POPs were
left essentially untouched and we will hope for considerable
improvements in model consistency in the near future to get a
better sense of what we can expect for the holiday period.
/Fliehman

&&

.AVIATION...
06Z TAFS: MVFR Ceilings and vis will be common over the region
through tomorrow morning as a moist boundary layer and light
winds exists under a strong low level inversion...with a mix of
MVFR and IFR conditions. Increasing lift into the moist boundary
layer will also bring a small chance for spotty freezing drizzle.
A moist Pacific storm system will spread thickening clouds over
the region on Friday with -SN/-RA to develop aft 18z in KEAT and
aft 00z at KGEG. Pcpn will vary btwn -SN and -FZRA at KEAT and
could be moderate at times. Warmer conditions will bring mostly
rain to KMWH/KGEG-KCOE/KPUW/KLWS. Breezy southerly winds and
lighter pcpn will keep KPUW/KLWS VFR conditions. /sb





&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        37  36  42  30  38  29 /  30 100  20  20  70  30
Coeur d`Alene  38  36  42  31  39  30 /  40 100  50  20  70  40
Pullman        42  37  44  33  41  31 /  10 100  70  50  70  60
Lewiston       46  41  48  36  46  34 /  10 100  60  30  60  40
Colville       36  34  42  23  37  23 /  90 100  20  10  60  20
Sandpoint      34  34  40  29  37  30 /  80 100  70  30  70  40
Kellogg        36  35  39  31  35  31 /  60 100  80  60  80  60
Moses Lake     36  33  47  28  44  29 /  90 100  10  10  30  10
Wenatchee      34  34  45  33  43  31 / 100 100  10  10  40  20
Omak           34  32  42  26  37  27 / 100 100  10  10  30  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST today for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon today to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon today to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST today for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon today to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon today to 6 PM PST Saturday for
     Northeast Mountains.

     Winter Weather Advisory from Noon today to 6 AM PST Saturday for
     Wenatchee Area.

&&

$$






000
FXUS66 KOTX 211128
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
328 AM PST FRI NOV 21 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.

&&

.DISCUSSION...
..BIGGEST SNOW MAKER SO FAR THIS  SEASON TO HIT MUCH OF THE INLAND
NORTHWEST LATER TODAY THROUGH SATURDAY...

Today and tonight ...Right now is the calm before the storm over
the Inland Northwest. All the region will see this morning is
some light precipitation in advance of a much wetter system
scheduled to move in later today. The 285k isentropic surface
continues to depict a fairly steep north-south pressure profile.
And this will become increasingly important this morning...as the
flow back toward more of a southerly orientation. This should make
light precipitation a little more widespread this
morning...especially over the northern third of Washington and the
northern half of the Idaho Panhandle. What makes this situation a
little more difficult than usual is the key dendritic layer will
be far from saturated. In fact only the layer from -10 to -15c
will have any moisture that nears saturation. This could lead to
periods of light freezing drizzle across the northern valleys in
addition to periodic snow. Amounts will be fairly light. By later
this morning though...the precipitation trends will begin to
increase steadily.

This precipitation increase will result from a good influx of
sub-tropical moisture. As of 2am...water vapor imagery was showing
a deep atmospheric river extending from west of Hawaii almost to
the Washington coast. This plume is expected to surge over the
Cascades by afternoon and remain over the region through much of
the night as a warm front invades the region. The front will
contribute to the warming temperatures over most valley locations.
The exception will be in the lee of the Cascades due to cold air
damming. The damming is expected to hold cold air over the
Waterville Plateau...Okanogan Valley...Wenatchee area...and
Cascade Valleys. Most of these locations still look like they will
see snow throughout the event. Models are fairly consistent on
dropping anywhere from .60-1.20 inches near the Cascades between
now and Saturday morning with values from .30-.80 inches across
most of the Inland Northwest. The combination of cold air and
heavy precipitation equates to a very good chance of heavy snow.
Valleys in the Cascades could see anywhere from 5-10 inches of
snow...with heavier amounts over the mountains...especially near
the crest. From Wenatchee to the Okanogan valleys...snow amount
should generally range from 3 to 6 inches...however that`s
assuming all the precipitation falls as snow. That notion is far
from a slam dunk for Wenatchee...the Wenatchee River Valley...and
Waterville Plateau...as there are signs that a fairly small
elevated melting layer will push into this area late this
afternoon or this evening. This would either put a strong damper
on the production of snow...or lead to a period of freezing rain.
The SREF would hedge toward the latter. This is far from a
confident notion as there are significant model differences. The
NAM would move this wedge over these areas almost at the onset of
the event...whereas the EC and GFS hold off until late this
evening. Not sure which model to believe...however the NAM may be
onto something as its handling surface temperatures much better
compared to surface observations. There is a much lesser chance of
this warm wedge moving as far north as Lake Chelan or the Okanogan
Valley. Elsewhere...the event looks primarily like a rain
maker...with snow levels gradually climbing to 3-4k feet over
northeast Washington and the north Idaho Panhandle...and anywhere
from 4-5k feet over the central Panhandle. There will likely be a
transition from snow to rain in the surrounding valleys...with 1
to 3 inches of snow a distinct possibility. Locally heavier
amounts are possible in valley locations close to the Canadian
border including Bonners Ferry...Metaline Falls and Laurier. The
widespread stratiform precipitation associated with the warm front
will transition to an unstable regime with the passage of a
significant shortwave trough and associated cold front. The front
should pass through the Cascades overnight and into the Idaho
Panhandle by early morning.

The front will finally provide the focus for mixing out all the
valleys with moderate to locally strong winds associated with good
downward momentum per cold air advection. Enough moisture and
instability will remain in place for numerous snow showers
primarily over the Idaho Panhandle and near the Cascades crest.
Meanwhile the lee valleys of the Cascades...Columbia Basin...and
the Spokane area will see a drying trend. It`s interesting to note
that with the passage of the cold front we will see a good
atmospheric destabilization and the NAM is actually showing some
small CAPE values over the central Panhandle by afternoon and
evening. This suggests we could see a significant development of
post frontal showers accompanied by locally heavy snow rates.
Elsewhere the main issue will be winds. Looks like the area could
see speeds approach wind advisory levels with sustained speeds of
20-25 mph with gusts of 40 mph possible. The strongest winds are
expected over the southeast Columbia Basin and Palouse. Based on
the myriad of highlights out at this time...we will defer this
issue to future shifts...but will give mention in hazardous
weather outlook. The strong winds will mix out any semblance of
modified arctic air...resulting in warming temps. However when
factoring in the winds...it certainly won`t feel warmer. fx

Saturday night through Tuesday night: A parade of systems will
in the northwest flow will bring precipitation every other day or
so. This comes with the potential for an extended period of wet
weather starting Monday night or Tuesday, accompanied by milder
and perhaps slightly above seasonal normal temperatures. However
model agreement falters by this time frame and forecast confidence
is degraded.

Saturday night one system pulls east. This and the northwest flow
will keep the threat of snow alive across the Panhandle and
southeast WA through evening. Chances will wane overnight as the
system exits. At the same time the lingering threat of snow near
the Cascade crest in the onshore flow will be bolstered by the
moisture and lift increasing with the next warm front overnight.
Meanwhile the remainder of central and eastern WA will continue to
be plagued by low clouds, as well as a threat of patchy fog.

Sunday the warm front moves into eastern WA and north ID,
bringing the next round of snow and rain. Models have sped up the
start of precipitation for the morning, at least slightly. By
afternoon the trailing occluded front comes into central WA,
lessening the precipitation in the lee of the Cascades and western
Basin. Yet east of here the threat will remain high through
evening, due to the passing occluded front, a lingering theta-e
ridge that weakens near the ID/WA border and the northwest flow.
Within this region models place the higher precipitation amounts
over southeast WA through the central Panhandle. The threat
appears to gradually wane overnight as the feature weakens.

As for precipitation-type and amounts: in the morning snow will
be the predominate threat. Exceptions will be over the deeper
Columbia Basin and L-C Valley where rain will be more likely. By
afternoon the main snow threat backs into the Cascades and lifts
toward the northern WA and ID Panhandle mountains, while mainly
rain or a rain/snow mix will be more likely over the Columbia
Basin eastward to the lower elevations of the Panhandle. As
compared to Friday`s system, the lift is weaker and the moisture
tap is not as impressive. So precipitation amounts look lower. Yet
with that said they are still modest in some areas. While models
generally depict less than a tenth toward the lee of the Cascades
and western Basin, they show between a tenth and a quarter of inch
over the eastern Basin. Near half an inch is depicted in the
eastern mountains and near an inch near the Cascade crest. Falling
as snow this could result in more moderate to locally heavy snow
amounts around the mountains. Yet even the lower elevations could
see some accumulations; early total suggest maybe a half inch to
an inch, with local amounts near two in some of the northern
mountain valleys.

Between Monday and Tuesday the next weather maker arrives. There
are still some questions about the evolution of the system,
including precipitation amounts and type. Yet it has the potential
to be a wet and milder period. By Monday afternoon and evening the
next warm front lifts across the region. The associated surface
low tracks from the central BC coast Monday morning to northeast
MT Tuesday morning. However models do not indicate a strong push
from the north behind that low. This is due to yet another system
moving across the Gulf of Alaska into western BC by Tuesday, which
should stalling things. This latter feature keeps a quasi-
stationary front across northeast WA through the central Panhandle
Monday night into Tuesday. Furthermore models show at least two
smaller-scale low pressure centers moves along that stalled front,
a relatively weak one Tuesday morning and a stronger low pressure
center late Tuesday into Tuesday night. Furthermore models show
another good subtropical moisture tap. PWATs rise to between 0.50
and 0.85 inches by Tuesday (or between 130 to 225% of normal).

So this evolution suggests another round of precipitation. Its
precise evolution may easily change. Yet right now models suggest
precipitation developing first around the Cascades and northern
mountains Monday (albeit light), before expanding across the
eastern third of WA and the ID Panhandle Monday night into Tuesday
morning. Chances remain high into Tuesday night with precipitation
rates on the rise, especially if models continue to depict that
stronger low moving along the stalled front. There are caveats to
this high precipitation threat. In the continued west-northwest
flow models paint the highest precipitation amounts across the
Cascade crest and across the Idaho Panhandle, save for the places
like the L-C Valley. Yet in the lee of the Cascades and western
Basin the west-northwest flow may provide enough to keep things
drier, due to the downsloping/shadow effect, at least for at least
a portion of this period. The best threat of precipitation in the
region may come around Tuesday afternoon into Tuesday evening,
when that second strong low moves along that stall boundary. In
addition if the stalled boundary remains further north, then the
precipitation threat may be diminished away from the all but the
Cascades and northern mountains.

As for precipitation-type during this time frame: snow levels
look to be on the rise. Initially models keep colder air in place.
Snow levels are currently projected to be around 1500 to 3500
feet, lowest toward NE WA and north ID. However all models show
the jet stream lifting north and miler air surging in. Monday
night into Tuesday morning models show snow level rise to between
5000 and 8000 feet across the Cascades through southeast WA,
though they linger near 2500 to 4000 feet across northeast WA and
the ID Panhandle. Going into Tuesday afternoon and night models
push snow levels up to between 7000 to 8000 feet over much of the
region, with the main sticky point at this time toward the
Canadian border where some still keep them at low as 3000 feet. So
these will continue to be fine-tuned, I`m sure. Overall this means
the potential for snow early Monday, changes to primarily rain
Monday night into Tuesday, save for the potential for snow to
linger longer at lower elevations northern counties where
confidence is lower. /J. Cote`

Wednesday through Friday: While many are planning for a busy
Thanksgiving travel period, the forecast continues to hinder the
planning process as it remains up in the air at this point with
lots of uncertainty. Just as models started to come into some sort
of agreement earlier today, the latest ECMWF jumped off the deep
end depicting what the GFS was showing several runs ago. While the
latest Euro now shows a fair amount of ridging on the west coast
leading to warmer and drier conditions, the GFS continues to
bring cooler northwesterly flow onshore keeping temps a bit cooler
and the pattern a bit more active. Due to the large amount of
inconsistencies in model comparison and run to run evaluation,
very few changes were made to the forecast as it could have hurt
more than helped at this point. The main change was to raise
temperatures and in turn snow levels as well to values above most
valley floors throughout the extended leading to any precipitation
to fall as valley rain and mountain snow. Both the GFS and ECMWF
had wet bulb zero temps depicted much further north than
previously shown so the mentioned changes were made. POPs were
left essentially untouched and we will hope for considerable
improvements in model consistency in the near future to get a
better sense of what we can expect for the holiday period.
/Fliehman

&&

.AVIATION...
06Z TAFS: MVFR Ceilings and vis will be common over the region
through tomorrow morning as a moist boundary layer and light
winds exists under a strong low level inversion...with a mix of
MVFR and IFR conditions. Increasing lift into the moist boundary
layer will also bring a small chance for spotty freezing drizzle.
A moist Pacific storm system will spread thickening clouds over
the region on Friday with -SN/-RA to develop aft 18z in KEAT and
aft 00z at KGEG. Pcpn will vary btwn -SN and -FZRA at KEAT and
could be moderate at times. Warmer conditions will bring mostly
rain to KMWH/KGEG-KCOE/KPUW/KLWS. Breezy southerly winds and
lighter pcpn will keep KPUW/KLWS VFR conditions. /sb





&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        37  36  42  30  38  29 /  30 100  20  20  70  30
Coeur d`Alene  38  36  42  31  39  30 /  40 100  50  20  70  40
Pullman        42  37  44  33  41  31 /  10 100  70  50  70  60
Lewiston       46  41  48  36  46  34 /  10 100  60  30  60  40
Colville       36  34  42  23  37  23 /  90 100  20  10  60  20
Sandpoint      34  34  40  29  37  30 /  80 100  70  30  70  40
Kellogg        36  35  39  31  35  31 /  60 100  80  60  80  60
Moses Lake     36  33  47  28  44  29 /  90 100  10  10  30  10
Wenatchee      34  34  45  33  43  31 / 100 100  10  10  40  20
Omak           34  32  42  26  37  27 / 100 100  10  10  30  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST today for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon today to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon today to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST today for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon today to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon today to 6 PM PST Saturday for
     Northeast Mountains.

     Winter Weather Advisory from Noon today to 6 AM PST Saturday for
     Wenatchee Area.

&&

$$





000
FXUS66 KOTX 211128
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
328 AM PST FRI NOV 21 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.

&&

.DISCUSSION...
..BIGGEST SNOW MAKER SO FAR THIS  SEASON TO HIT MUCH OF THE INLAND
NORTHWEST LATER TODAY THROUGH SATURDAY...

Today and tonight ...Right now is the calm before the storm over
the Inland Northwest. All the region will see this morning is
some light precipitation in advance of a much wetter system
scheduled to move in later today. The 285k isentropic surface
continues to depict a fairly steep north-south pressure profile.
And this will become increasingly important this morning...as the
flow back toward more of a southerly orientation. This should make
light precipitation a little more widespread this
morning...especially over the northern third of Washington and the
northern half of the Idaho Panhandle. What makes this situation a
little more difficult than usual is the key dendritic layer will
be far from saturated. In fact only the layer from -10 to -15c
will have any moisture that nears saturation. This could lead to
periods of light freezing drizzle across the northern valleys in
addition to periodic snow. Amounts will be fairly light. By later
this morning though...the precipitation trends will begin to
increase steadily.

This precipitation increase will result from a good influx of
sub-tropical moisture. As of 2am...water vapor imagery was showing
a deep atmospheric river extending from west of Hawaii almost to
the Washington coast. This plume is expected to surge over the
Cascades by afternoon and remain over the region through much of
the night as a warm front invades the region. The front will
contribute to the warming temperatures over most valley locations.
The exception will be in the lee of the Cascades due to cold air
damming. The damming is expected to hold cold air over the
Waterville Plateau...Okanogan Valley...Wenatchee area...and
Cascade Valleys. Most of these locations still look like they will
see snow throughout the event. Models are fairly consistent on
dropping anywhere from .60-1.20 inches near the Cascades between
now and Saturday morning with values from .30-.80 inches across
most of the Inland Northwest. The combination of cold air and
heavy precipitation equates to a very good chance of heavy snow.
Valleys in the Cascades could see anywhere from 5-10 inches of
snow...with heavier amounts over the mountains...especially near
the crest. From Wenatchee to the Okanogan valleys...snow amount
should generally range from 3 to 6 inches...however that`s
assuming all the precipitation falls as snow. That notion is far
from a slam dunk for Wenatchee...the Wenatchee River Valley...and
Waterville Plateau...as there are signs that a fairly small
elevated melting layer will push into this area late this
afternoon or this evening. This would either put a strong damper
on the production of snow...or lead to a period of freezing rain.
The SREF would hedge toward the latter. This is far from a
confident notion as there are significant model differences. The
NAM would move this wedge over these areas almost at the onset of
the event...whereas the EC and GFS hold off until late this
evening. Not sure which model to believe...however the NAM may be
onto something as its handling surface temperatures much better
compared to surface observations. There is a much lesser chance of
this warm wedge moving as far north as Lake Chelan or the Okanogan
Valley. Elsewhere...the event looks primarily like a rain
maker...with snow levels gradually climbing to 3-4k feet over
northeast Washington and the north Idaho Panhandle...and anywhere
from 4-5k feet over the central Panhandle. There will likely be a
transition from snow to rain in the surrounding valleys...with 1
to 3 inches of snow a distinct possibility. Locally heavier
amounts are possible in valley locations close to the Canadian
border including Bonners Ferry...Metaline Falls and Laurier. The
widespread stratiform precipitation associated with the warm front
will transition to an unstable regime with the passage of a
significant shortwave trough and associated cold front. The front
should pass through the Cascades overnight and into the Idaho
Panhandle by early morning.

The front will finally provide the focus for mixing out all the
valleys with moderate to locally strong winds associated with good
downward momentum per cold air advection. Enough moisture and
instability will remain in place for numerous snow showers
primarily over the Idaho Panhandle and near the Cascades crest.
Meanwhile the lee valleys of the Cascades...Columbia Basin...and
the Spokane area will see a drying trend. It`s interesting to note
that with the passage of the cold front we will see a good
atmospheric destabilization and the NAM is actually showing some
small CAPE values over the central Panhandle by afternoon and
evening. This suggests we could see a significant development of
post frontal showers accompanied by locally heavy snow rates.
Elsewhere the main issue will be winds. Looks like the area could
see speeds approach wind advisory levels with sustained speeds of
20-25 mph with gusts of 40 mph possible. The strongest winds are
expected over the southeast Columbia Basin and Palouse. Based on
the myriad of highlights out at this time...we will defer this
issue to future shifts...but will give mention in hazardous
weather outlook. The strong winds will mix out any semblance of
modified arctic air...resulting in warming temps. However when
factoring in the winds...it certainly won`t feel warmer. fx

Saturday night through Tuesday night: A parade of systems will
in the northwest flow will bring precipitation every other day or
so. This comes with the potential for an extended period of wet
weather starting Monday night or Tuesday, accompanied by milder
and perhaps slightly above seasonal normal temperatures. However
model agreement falters by this time frame and forecast confidence
is degraded.

Saturday night one system pulls east. This and the northwest flow
will keep the threat of snow alive across the Panhandle and
southeast WA through evening. Chances will wane overnight as the
system exits. At the same time the lingering threat of snow near
the Cascade crest in the onshore flow will be bolstered by the
moisture and lift increasing with the next warm front overnight.
Meanwhile the remainder of central and eastern WA will continue to
be plagued by low clouds, as well as a threat of patchy fog.

Sunday the warm front moves into eastern WA and north ID,
bringing the next round of snow and rain. Models have sped up the
start of precipitation for the morning, at least slightly. By
afternoon the trailing occluded front comes into central WA,
lessening the precipitation in the lee of the Cascades and western
Basin. Yet east of here the threat will remain high through
evening, due to the passing occluded front, a lingering theta-e
ridge that weakens near the ID/WA border and the northwest flow.
Within this region models place the higher precipitation amounts
over southeast WA through the central Panhandle. The threat
appears to gradually wane overnight as the feature weakens.

As for precipitation-type and amounts: in the morning snow will
be the predominate threat. Exceptions will be over the deeper
Columbia Basin and L-C Valley where rain will be more likely. By
afternoon the main snow threat backs into the Cascades and lifts
toward the northern WA and ID Panhandle mountains, while mainly
rain or a rain/snow mix will be more likely over the Columbia
Basin eastward to the lower elevations of the Panhandle. As
compared to Friday`s system, the lift is weaker and the moisture
tap is not as impressive. So precipitation amounts look lower. Yet
with that said they are still modest in some areas. While models
generally depict less than a tenth toward the lee of the Cascades
and western Basin, they show between a tenth and a quarter of inch
over the eastern Basin. Near half an inch is depicted in the
eastern mountains and near an inch near the Cascade crest. Falling
as snow this could result in more moderate to locally heavy snow
amounts around the mountains. Yet even the lower elevations could
see some accumulations; early total suggest maybe a half inch to
an inch, with local amounts near two in some of the northern
mountain valleys.

Between Monday and Tuesday the next weather maker arrives. There
are still some questions about the evolution of the system,
including precipitation amounts and type. Yet it has the potential
to be a wet and milder period. By Monday afternoon and evening the
next warm front lifts across the region. The associated surface
low tracks from the central BC coast Monday morning to northeast
MT Tuesday morning. However models do not indicate a strong push
from the north behind that low. This is due to yet another system
moving across the Gulf of Alaska into western BC by Tuesday, which
should stalling things. This latter feature keeps a quasi-
stationary front across northeast WA through the central Panhandle
Monday night into Tuesday. Furthermore models show at least two
smaller-scale low pressure centers moves along that stalled front,
a relatively weak one Tuesday morning and a stronger low pressure
center late Tuesday into Tuesday night. Furthermore models show
another good subtropical moisture tap. PWATs rise to between 0.50
and 0.85 inches by Tuesday (or between 130 to 225% of normal).

So this evolution suggests another round of precipitation. Its
precise evolution may easily change. Yet right now models suggest
precipitation developing first around the Cascades and northern
mountains Monday (albeit light), before expanding across the
eastern third of WA and the ID Panhandle Monday night into Tuesday
morning. Chances remain high into Tuesday night with precipitation
rates on the rise, especially if models continue to depict that
stronger low moving along the stalled front. There are caveats to
this high precipitation threat. In the continued west-northwest
flow models paint the highest precipitation amounts across the
Cascade crest and across the Idaho Panhandle, save for the places
like the L-C Valley. Yet in the lee of the Cascades and western
Basin the west-northwest flow may provide enough to keep things
drier, due to the downsloping/shadow effect, at least for at least
a portion of this period. The best threat of precipitation in the
region may come around Tuesday afternoon into Tuesday evening,
when that second strong low moves along that stall boundary. In
addition if the stalled boundary remains further north, then the
precipitation threat may be diminished away from the all but the
Cascades and northern mountains.

As for precipitation-type during this time frame: snow levels
look to be on the rise. Initially models keep colder air in place.
Snow levels are currently projected to be around 1500 to 3500
feet, lowest toward NE WA and north ID. However all models show
the jet stream lifting north and miler air surging in. Monday
night into Tuesday morning models show snow level rise to between
5000 and 8000 feet across the Cascades through southeast WA,
though they linger near 2500 to 4000 feet across northeast WA and
the ID Panhandle. Going into Tuesday afternoon and night models
push snow levels up to between 7000 to 8000 feet over much of the
region, with the main sticky point at this time toward the
Canadian border where some still keep them at low as 3000 feet. So
these will continue to be fine-tuned, I`m sure. Overall this means
the potential for snow early Monday, changes to primarily rain
Monday night into Tuesday, save for the potential for snow to
linger longer at lower elevations northern counties where
confidence is lower. /J. Cote`

Wednesday through Friday: While many are planning for a busy
Thanksgiving travel period, the forecast continues to hinder the
planning process as it remains up in the air at this point with
lots of uncertainty. Just as models started to come into some sort
of agreement earlier today, the latest ECMWF jumped off the deep
end depicting what the GFS was showing several runs ago. While the
latest Euro now shows a fair amount of ridging on the west coast
leading to warmer and drier conditions, the GFS continues to
bring cooler northwesterly flow onshore keeping temps a bit cooler
and the pattern a bit more active. Due to the large amount of
inconsistencies in model comparison and run to run evaluation,
very few changes were made to the forecast as it could have hurt
more than helped at this point. The main change was to raise
temperatures and in turn snow levels as well to values above most
valley floors throughout the extended leading to any precipitation
to fall as valley rain and mountain snow. Both the GFS and ECMWF
had wet bulb zero temps depicted much further north than
previously shown so the mentioned changes were made. POPs were
left essentially untouched and we will hope for considerable
improvements in model consistency in the near future to get a
better sense of what we can expect for the holiday period.
/Fliehman

&&

.AVIATION...
06Z TAFS: MVFR Ceilings and vis will be common over the region
through tomorrow morning as a moist boundary layer and light
winds exists under a strong low level inversion...with a mix of
MVFR and IFR conditions. Increasing lift into the moist boundary
layer will also bring a small chance for spotty freezing drizzle.
A moist Pacific storm system will spread thickening clouds over
the region on Friday with -SN/-RA to develop aft 18z in KEAT and
aft 00z at KGEG. Pcpn will vary btwn -SN and -FZRA at KEAT and
could be moderate at times. Warmer conditions will bring mostly
rain to KMWH/KGEG-KCOE/KPUW/KLWS. Breezy southerly winds and
lighter pcpn will keep KPUW/KLWS VFR conditions. /sb





&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        37  36  42  30  38  29 /  30 100  20  20  70  30
Coeur d`Alene  38  36  42  31  39  30 /  40 100  50  20  70  40
Pullman        42  37  44  33  41  31 /  10 100  70  50  70  60
Lewiston       46  41  48  36  46  34 /  10 100  60  30  60  40
Colville       36  34  42  23  37  23 /  90 100  20  10  60  20
Sandpoint      34  34  40  29  37  30 /  80 100  70  30  70  40
Kellogg        36  35  39  31  35  31 /  60 100  80  60  80  60
Moses Lake     36  33  47  28  44  29 /  90 100  10  10  30  10
Wenatchee      34  34  45  33  43  31 / 100 100  10  10  40  20
Omak           34  32  42  26  37  27 / 100 100  10  10  30  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST today for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon today to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon today to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST today for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon today to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon today to 6 PM PST Saturday for
     Northeast Mountains.

     Winter Weather Advisory from Noon today to 6 AM PST Saturday for
     Wenatchee Area.

&&

$$





000
FXUS66 KOTX 210708
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1108 PM PST THU NOV 20 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.



&&

.DISCUSSION...
Second update to add winter weather advisory for the Wenatchee
Zone. At this time, looks like there is a potential for 1-2
inches near Wenatchee and two to four inches in northern areas of
the zone with locally heavier amounts in the higher benches.
Another reason for the advisory was the threat for a mixed bag of
precipitation as the warmer air arrives. Could see periods of
freezing rain or sleet and overall, travel conditions could be
very slick even if snow amounts are underdone. /sb


&&

.AVIATION...
06Z TAFS: MVFR Ceilings and vis will be common over the region
through tomorrow morning as a moist boundary layer and light
winds exists under a strong low level inversion...with a mix of
MVFR and IFR conditions. Increasing lift into the moist boundary
layer will also bring a small chance for spotty freezing drizzle.
A moist Pacific storm system will spread thickening clouds over
the region on Friday with -SN/-RA to develop aft 18z in KEAT and
aft 00z at KGEG. Pcpn will vary btwn -SN and -FZRA at KEAT and
could be moderate at times. Warmer conditions will bring mostly
rain to KMWH/KGEG-KCOE/KPUW/KLWS. Breezy southerly winds and
lighter pcpn will keep KPUW/KLWS VFR conditions. /sb




&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        28  37  36  43  30  40 /  20  30 100  30  20  60
Coeur d`Alene  30  39  36  42  31  39 /  30  50 100  50  30  70
Pullman        33  41  36  43  34  42 /  10  10 100  70  40  60
Lewiston       35  44  40  48  36  47 /  10  10 100  70  30  50
Colville       27  37  34  44  20  38 /  30  70 100  50  10  60
Sandpoint      29  37  35  41  29  37 /  50  70 100  70  30  70
Kellogg        31  37  36  39  32  36 /  40  50 100  80  60  80
Moses Lake     26  36  35  48  30  46 /  10  50 100  10  10  30
Wenatchee      30  35  35  47  34  45 /  10  80 100  10  10  40
Omak           30  35  33  45  27  39 /  10  90 100  20  10  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon Friday to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northeast Mountains.

     Winter Weather Advisory from Noon Friday to 6 AM PST Saturday
     for Wenatchee Area.

&&

$$





000
FXUS66 KOTX 210457
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
857 PM PST THU NOV 20 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.


&&

.DISCUSSION...

...REFREEZING ROADS AND POTENTIAL FOR additional FREEZING DRIZZLE
TO CREATE SLICK TRAVEL OVERNIGHT...

Evening update: A complex and active winter weather pattern will
be the focus for the next 36 hours. Here are the changes we have
made or will be focusing on tonight.

For tonight, we have added patchy freezing drizzle to majority of
the Columbia Basin, West Plains, and northern Palouse. Light
echoes continue to blossom across the region as warm air
advection/isentropic ascent strengthens ahead of a
weak...splitting trof currently moving across the Cascades.
Further investigation into soundings suggest the moisture will
generally remain below the dendritic layer (ie. drizzle) ahead
and behind the weak wave but could briefly saturate this layer as
it passes through. While confidence is generally low, this would
indicate drizzle falling out of the stratus (low clouds)...briefly
becoming snow, sleet, or rain/freezing rain, then transitioning
back to drizzle. This is where surface temperatures become very
important. Most locations remain below freezing at this hour. The
exception is the Palouse, L-C Valley, and Camas Prairie which are
in the upper 30s to lower 40s and carrying dewpoints in the mid
30s suggesting temperatures will not fall much tonight away from
the mid 30s. On top of that, moisture from earlier precipitation
will likely refreeze to surfaces. All things considered, there is
a good chance that motorists will encounter icy travel across much
of the region.

For Friday, we will be trying to fine tune the Wenatchee Area and
deciding whether to include any winter highlights. The snowfall
for Wenatchee Area looks ok, (one inch) but higher amounts could
will be possible in northern sections of the zones up near Chelan
and across the higher benches. But here is where it gets
challenging, BUFKIT sounding data suggest a warm nose into
Wenatchee while the MOS guidance keeps surface temperatures at or
below freezing. This raises concern that when the transition from
snow to rain occurs, precip may be in the form of freezing rain or
sleet. There is always the potential that the models are warming
too fast aloft and it all remains snow. We feel confident for
moderate QPF...but precip type will be difficult in an area with
so many microclimates. This is something that may be addressed
with a winter storm update this evening or potentially overnight.
/sb


&&

.AVIATION...
00Z TAFS: MVFR Ceilings and vis will be common over the region
through tonight as a moist boundary layer and light winds exists
under a strong low level inversion...with IFR conditions likely
redeveloping mainly at the KMWH and KGEG vicinity TAF sites
overnight. On Friday an approaching Pacific storm system will
spread thickening clouds over the region as a warm front develops.
MVFR ceilings will probably remain common across the Columbia
basin except fro KLWS where VFR conditions are expected. Light
snow or rain may begin at the KEAT TAF site during the afternoon.
/MJF



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        28  37  36  43  30  40 /  20  30 100  30  20  60
Coeur d`Alene  30  39  36  42  31  39 /  30  50 100  50  30  70
Pullman        33  41  36  43  34  42 /  10  10 100  70  40  60
Lewiston       35  44  40  48  36  47 /  10  10 100  70  30  50
Colville       27  37  34  44  20  38 /  30  70 100  50  10  60
Sandpoint      29  37  35  41  29  37 /  50  70 100  70  30  70
Kellogg        31  37  36  39  32  36 /  40  50 100  80  60  80
Moses Lake     26  36  35  48  30  46 /  10  50 100  10  10  30
Wenatchee      30  35  35  47  34  45 /  10  80 100  10  10  40
Omak           30  35  33  45  27  39 /  10  90 100  20  10  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon Friday to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northeast Mountains.

&&

$$






000
FXUS66 KOTX 210457
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
857 PM PST THU NOV 20 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.


&&

.DISCUSSION...

...REFREEZING ROADS AND POTENTIAL FOR additional FREEZING DRIZZLE
TO CREATE SLICK TRAVEL OVERNIGHT...

Evening update: A complex and active winter weather pattern will
be the focus for the next 36 hours. Here are the changes we have
made or will be focusing on tonight.

For tonight, we have added patchy freezing drizzle to majority of
the Columbia Basin, West Plains, and northern Palouse. Light
echoes continue to blossom across the region as warm air
advection/isentropic ascent strengthens ahead of a
weak...splitting trof currently moving across the Cascades.
Further investigation into soundings suggest the moisture will
generally remain below the dendritic layer (ie. drizzle) ahead
and behind the weak wave but could briefly saturate this layer as
it passes through. While confidence is generally low, this would
indicate drizzle falling out of the stratus (low clouds)...briefly
becoming snow, sleet, or rain/freezing rain, then transitioning
back to drizzle. This is where surface temperatures become very
important. Most locations remain below freezing at this hour. The
exception is the Palouse, L-C Valley, and Camas Prairie which are
in the upper 30s to lower 40s and carrying dewpoints in the mid
30s suggesting temperatures will not fall much tonight away from
the mid 30s. On top of that, moisture from earlier precipitation
will likely refreeze to surfaces. All things considered, there is
a good chance that motorists will encounter icy travel across much
of the region.

For Friday, we will be trying to fine tune the Wenatchee Area and
deciding whether to include any winter highlights. The snowfall
for Wenatchee Area looks ok, (one inch) but higher amounts could
will be possible in northern sections of the zones up near Chelan
and across the higher benches. But here is where it gets
challenging, BUFKIT sounding data suggest a warm nose into
Wenatchee while the MOS guidance keeps surface temperatures at or
below freezing. This raises concern that when the transition from
snow to rain occurs, precip may be in the form of freezing rain or
sleet. There is always the potential that the models are warming
too fast aloft and it all remains snow. We feel confident for
moderate QPF...but precip type will be difficult in an area with
so many microclimates. This is something that may be addressed
with a winter storm update this evening or potentially overnight.
/sb


&&

.AVIATION...
00Z TAFS: MVFR Ceilings and vis will be common over the region
through tonight as a moist boundary layer and light winds exists
under a strong low level inversion...with IFR conditions likely
redeveloping mainly at the KMWH and KGEG vicinity TAF sites
overnight. On Friday an approaching Pacific storm system will
spread thickening clouds over the region as a warm front develops.
MVFR ceilings will probably remain common across the Columbia
basin except fro KLWS where VFR conditions are expected. Light
snow or rain may begin at the KEAT TAF site during the afternoon.
/MJF



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        28  37  36  43  30  40 /  20  30 100  30  20  60
Coeur d`Alene  30  39  36  42  31  39 /  30  50 100  50  30  70
Pullman        33  41  36  43  34  42 /  10  10 100  70  40  60
Lewiston       35  44  40  48  36  47 /  10  10 100  70  30  50
Colville       27  37  34  44  20  38 /  30  70 100  50  10  60
Sandpoint      29  37  35  41  29  37 /  50  70 100  70  30  70
Kellogg        31  37  36  39  32  36 /  40  50 100  80  60  80
Moses Lake     26  36  35  48  30  46 /  10  50 100  10  10  30
Wenatchee      30  35  35  47  34  45 /  10  80 100  10  10  40
Omak           30  35  33  45  27  39 /  10  90 100  20  10  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon Friday to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northeast Mountains.

&&

$$





000
FXUS66 KOTX 202345
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
345 PM PST THU NOV 20 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.

&&

.DISCUSSION...
Tonight...A rather mushy but somewhat benign night is in store
fro the region. Satellite and radar indicate the exiting storm
band that brought light snow to the region on track to move off
to the east early this evening. Meanwhile the next minor trough is
diving into California with a weak northern branch wave scuttling
into southern British Columbia. Models suggest a weak and
shearing wave will exist between these two dynamic centers and
will transit the region tonight...but the weakening nature of this
system should bring little beyond a few snow showers concentrated
over the northeastern zones late tonight. Once again fog and the
potential fro some freezing drizzle will exist in the deep basin
where stubborn arctic air is pooling in these low elevations.

Friday through Saturday...Latest models are in good agreement and
consistent with bringing a very moist and very dynamic wave
through the region during this period. A strong warm front will
make short work of the leftover and now modified arctic air over
the eastern half of the forecast area with snow levels expected to
rise to the 4000 foot region. In the west the cold air will be
slower to scrub and snow levels will stay low through much of this
event...perhaps all of it in the northern Cascade valleys and the
Okanogan valley. Snow levels will rise...but not as aggressively
over the southern portions of the deep basin...leading to the
likelihood of at least minimal warning criteria accumulating snow
on the Waterville Plateau. The southern valleys such as the
Wenatchee River valley will see some snow but amounts will be
overall fairly light. The Cascade mountains above 3000 to 4000
feet will get hammered with snow with a 12 hour period of moist
isentropic lift augmented by upslope southeasterly low level flow.
All the existing Winter Storm Watches will be upgraded to warnings
with the afternoon package...as well as adding the Okanogan and
Waterville Plateau to the highlight mix.

Beginning Friday morning the isentropic moistening process
will promote increasing clouds...with light snow beginning over
the northern zones in the early afternoon. By Friday evening an
almost universal field of valley rain and mountain snow will
envelop the region...except for the aforementioned north
Cascades/Okanogan where snow will continue as the dominant
meteor.

A strong cold front will rip through the region Saturday morning
largely ending precipitation in the Cascades lee but promoting
enhanced upslope snow showers into the Idaho Panhandle mountains.
The big story on Saturday will be very windy conditions especially
over the eastern basin exposed terrain with gust potential picked
off of model sounding mixed layers up to 45 or 50 mph. Saturday
will be a well mixed day with much milder temperatures than we
have grown accustomed to. /Fugazzi

Saturday Night through Monday Night: In the wake of Saturday`s
cold front, the breezy afternoon winds will gradually subside
overnight. Don`t see a great push of dry air behind this front. We
should have clearing skies in most places. This will allow
temperatures to drop sharply, especially in the northern valleys.
Then fog and stratus will form overnight and persist into Sunday
morning. The northwesterly flow is very unstable so the Panhandle
mountains will continue to pile up snow Saturday night.

By Sunday, another Pacific system will quickly clip across the
area. Due to the strong westerly flow, the Cascades and Panhandle
will be favored with this system. Spokane metro area could see
a little snow Sunday morning but will change to rain in the
afternoon.

Confidence is much lower for Monday`s event. The models really
diverge from each other on track and timing so I have about as
much chance of being wrong as right on the forecast. Went with
likely wording for the Cascades/Panhandle and chance wording
elsewhere. As usual, Highway 2/I-90 will be the dividing line
between rain and snow.  RJ

Tuesday through Thanksgiving: This portion of the forecast is
quite complicated, which is important because it envelops one of
the busiest travels days of the year. Unfortunately, the models
are having a hard time coming to some agreement, which makes this,
unfortunately, a low confidence forecast. There is some higher
confidence for Tuesday, as a shortwave traversed the region in
northwest flow. This will bring better chances of precipitation to
the Cascades, and the higher terrain of northeast Washington and
the Idaho Panhandle. It was happens after Tuesday where things get
all mucked up. The Euro model has stuck to its guns, carving out a
larger trough over much of the US, keeping the Inland Northwest on
the western edge of the cold air mass. The GFS keeps any
influence of the cold air mass well to the east, instead building
a ridge of high pressure over the region. This ridge is more
amplified than it`s previous solutions. So, all in all, we didn`t
stray much from the previous forecasts, which weighted towards the
more consistent solution (colder). While this would bring snow
levels into the valleys, the north-northwesterly flow does not
look like it will have a ton of moisture to work with. Lots of
fine-tuning will be made to this portion of the forecast for sure.
ty

&&

.AVIATION...
00Z TAFS: MVFR Ceilings and vis will be common over the region
through tonight as a moist boundary layer and light winds exists
under a strong low level inversion...with IFR conditions likely
redeveloping mainly at the KMWH and KGEG vicinity TAF sites
overnight. On Friday an approaching Pacific storm system will
spread thickening clouds over the region as a warm front develops.
MVFR ceilings will probably remain common across the Columbia
basin except fro KLWS where VFR conditions are expected. Light
snow or rain may begin at the KEAT TAF site during the afternoon.
/MJF


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        28  37  36  43  30  40 /  20  30 100  30  20  60
Coeur d`Alene  30  39  36  42  31  39 /  30  50 100  50  30  70
Pullman        29  41  36  43  34  42 /  10  10 100  70  40  60
Lewiston       32  44  40  48  36  47 /  10  10 100  70  30  50
Colville       25  37  34  44  20  38 /  30  70 100  50  10  60
Sandpoint      29  37  35  41  29  37 /  50  70 100  70  30  70
Kellogg        31  37  36  39  32  36 /  40  50 100  80  60  80
Moses Lake     24  36  35  48  30  46 /  10  50 100  10  10  30
Wenatchee      30  35  35  47  34  45 /  10  80 100  10  10  40
Omak           30  35  33  45  27  39 /  10  90 100  20  10  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon Friday to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northeast Mountains.

&&

$$






000
FXUS66 KOTX 202345
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
345 PM PST THU NOV 20 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.

&&

.DISCUSSION...
Tonight...A rather mushy but somewhat benign night is in store
fro the region. Satellite and radar indicate the exiting storm
band that brought light snow to the region on track to move off
to the east early this evening. Meanwhile the next minor trough is
diving into California with a weak northern branch wave scuttling
into southern British Columbia. Models suggest a weak and
shearing wave will exist between these two dynamic centers and
will transit the region tonight...but the weakening nature of this
system should bring little beyond a few snow showers concentrated
over the northeastern zones late tonight. Once again fog and the
potential fro some freezing drizzle will exist in the deep basin
where stubborn arctic air is pooling in these low elevations.

Friday through Saturday...Latest models are in good agreement and
consistent with bringing a very moist and very dynamic wave
through the region during this period. A strong warm front will
make short work of the leftover and now modified arctic air over
the eastern half of the forecast area with snow levels expected to
rise to the 4000 foot region. In the west the cold air will be
slower to scrub and snow levels will stay low through much of this
event...perhaps all of it in the northern Cascade valleys and the
Okanogan valley. Snow levels will rise...but not as aggressively
over the southern portions of the deep basin...leading to the
likelihood of at least minimal warning criteria accumulating snow
on the Waterville Plateau. The southern valleys such as the
Wenatchee River valley will see some snow but amounts will be
overall fairly light. The Cascade mountains above 3000 to 4000
feet will get hammered with snow with a 12 hour period of moist
isentropic lift augmented by upslope southeasterly low level flow.
All the existing Winter Storm Watches will be upgraded to warnings
with the afternoon package...as well as adding the Okanogan and
Waterville Plateau to the highlight mix.

Beginning Friday morning the isentropic moistening process
will promote increasing clouds...with light snow beginning over
the northern zones in the early afternoon. By Friday evening an
almost universal field of valley rain and mountain snow will
envelop the region...except for the aforementioned north
Cascades/Okanogan where snow will continue as the dominant
meteor.

A strong cold front will rip through the region Saturday morning
largely ending precipitation in the Cascades lee but promoting
enhanced upslope snow showers into the Idaho Panhandle mountains.
The big story on Saturday will be very windy conditions especially
over the eastern basin exposed terrain with gust potential picked
off of model sounding mixed layers up to 45 or 50 mph. Saturday
will be a well mixed day with much milder temperatures than we
have grown accustomed to. /Fugazzi

Saturday Night through Monday Night: In the wake of Saturday`s
cold front, the breezy afternoon winds will gradually subside
overnight. Don`t see a great push of dry air behind this front. We
should have clearing skies in most places. This will allow
temperatures to drop sharply, especially in the northern valleys.
Then fog and stratus will form overnight and persist into Sunday
morning. The northwesterly flow is very unstable so the Panhandle
mountains will continue to pile up snow Saturday night.

By Sunday, another Pacific system will quickly clip across the
area. Due to the strong westerly flow, the Cascades and Panhandle
will be favored with this system. Spokane metro area could see
a little snow Sunday morning but will change to rain in the
afternoon.

Confidence is much lower for Monday`s event. The models really
diverge from each other on track and timing so I have about as
much chance of being wrong as right on the forecast. Went with
likely wording for the Cascades/Panhandle and chance wording
elsewhere. As usual, Highway 2/I-90 will be the dividing line
between rain and snow.  RJ

Tuesday through Thanksgiving: This portion of the forecast is
quite complicated, which is important because it envelops one of
the busiest travels days of the year. Unfortunately, the models
are having a hard time coming to some agreement, which makes this,
unfortunately, a low confidence forecast. There is some higher
confidence for Tuesday, as a shortwave traversed the region in
northwest flow. This will bring better chances of precipitation to
the Cascades, and the higher terrain of northeast Washington and
the Idaho Panhandle. It was happens after Tuesday where things get
all mucked up. The Euro model has stuck to its guns, carving out a
larger trough over much of the US, keeping the Inland Northwest on
the western edge of the cold air mass. The GFS keeps any
influence of the cold air mass well to the east, instead building
a ridge of high pressure over the region. This ridge is more
amplified than it`s previous solutions. So, all in all, we didn`t
stray much from the previous forecasts, which weighted towards the
more consistent solution (colder). While this would bring snow
levels into the valleys, the north-northwesterly flow does not
look like it will have a ton of moisture to work with. Lots of
fine-tuning will be made to this portion of the forecast for sure.
ty

&&

.AVIATION...
00Z TAFS: MVFR Ceilings and vis will be common over the region
through tonight as a moist boundary layer and light winds exists
under a strong low level inversion...with IFR conditions likely
redeveloping mainly at the KMWH and KGEG vicinity TAF sites
overnight. On Friday an approaching Pacific storm system will
spread thickening clouds over the region as a warm front develops.
MVFR ceilings will probably remain common across the Columbia
basin except fro KLWS where VFR conditions are expected. Light
snow or rain may begin at the KEAT TAF site during the afternoon.
/MJF


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        28  37  36  43  30  40 /  20  30 100  30  20  60
Coeur d`Alene  30  39  36  42  31  39 /  30  50 100  50  30  70
Pullman        29  41  36  43  34  42 /  10  10 100  70  40  60
Lewiston       32  44  40  48  36  47 /  10  10 100  70  30  50
Colville       25  37  34  44  20  38 /  30  70 100  50  10  60
Sandpoint      29  37  35  41  29  37 /  50  70 100  70  30  70
Kellogg        31  37  36  39  32  36 /  40  50 100  80  60  80
Moses Lake     24  36  35  48  30  46 /  10  50 100  10  10  30
Wenatchee      30  35  35  47  34  45 /  10  80 100  10  10  40
Omak           30  35  33  45  27  39 /  10  90 100  20  10  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon Friday to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northeast Mountains.

&&

$$





000
FXUS66 KOTX 202219
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
218 PM PST THU NOV 20 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.

&&

.DISCUSSION...
Tonight...A rather mushy but somewhat benign night is in store
fro the region. Satellite and radar indicate the exiting storm
band that brought light snow to the region on track to move off
to the east early this evening. Meanwhile the next minor trough is
diving into California with a weak northern branch wave scuttling
into southern British Columbia. Models suggest a weak and
shearing wave will exist between these two dynamic centers and
will transit the region tonight...but the weakening nature of this
system should bring little beyond a few snow showers concentrated
over the northeastern zones late tonight. Once again fog and the
potential fro some freezing drizzle will exist in the deep basin
where stubborn arctic air is pooling in these low elevations.

Friday through Saturday...Latest models are in good agreement and
consistent with bringing a very moist and very dynamic wave
through the region during this period. A strong warm front will
make short work of the leftover and now modified arctic air over
the eastern half of the forecast area with snow levels expected to
rise to the 4000 foot region. In the west the cold air will be
slower to scrub and snow levels will stay low through much of this
event...perhaps all of it in the northern Cascade valleys and the
Okanogan valley. Snow levels will rise...but not as aggressively
over the southern portions of the deep basin...leading to the
likelihood of at least minimal warning criteria accumulating snow
on the Waterville Plateau. The southern valleys such as the
Wenatchee River valley will see some snow but amounts will be
overall fairly light. The Cascade mountains above 3000 to 4000
feet will get hammered with snow with a 12 hour period of moist
isentropic lift augmented by upslope southeasterly low level flow.
All the existing Winter Storm Watches will be upgraded to warnings
with the afternoon package...as well as adding the Okanogan and
Waterville Plateau to the highlight mix.

Beginning Friday morning the isentropic moistening process
will promote increasing clouds...with light snow beginning over
the northern zones in the early afternoon. By Friday evening an
almost universal field of valley rain and mountain snow will
envelop the region...except for the aforementioned north
Cascades/Okanogan where snow will continue as the dominant
meteor.

A strong cold front will rip through the region Saturday morning
largely ending precipitation in the Cascades lee but promoting
enhanced upslope snow showers into the Idaho Panhandle mountains.
The big story on Saturday will be very windy conditions especially
over the eastern basin exposed terrain with gust potential picked
off of model sounding mixed layers up to 45 or 50 mph. Saturday
will be a well mixed day with much milder temperatures than we
have grown accustomed to. /Fugazzi

Saturday Night through Monday Night: In the wake of Saturday`s
cold front, the breezy afternoon winds will gradually subside
overnight. Don`t see a great push of dry air behind this front. We
should have clearing skies in most places. This will allow
temperatures to drop sharply, especially in the northern valleys.
Then fog and stratus will form overnight and persist into Sunday
morning. The northwesterly flow is very unstable so the Panhandle
mountains will continue to pile up snow Saturday night.

By Sunday, another Pacific system will quickly clip across the
area. Due to the strong westerly flow, the Cascades and Panhandle
will be favored with this system. Spokane metro area could see
a little snow Sunday morning but will change to rain in the
afternoon.

Confidence is much lower for Monday`s event. The models really
diverge from each other on track and timing so I have about as
much chance of being wrong as right on the forecast. Went with
likely wording for the Cascades/Panhandle and chance wording
elsewhere. As usual, Highway 2/I-90 will be the dividing line
between rain and snow.  RJ

Tuesday through Thanksgiving: This portion of the forecast is
quite complicated, which is important because it envelops one of
the busiest travels days of the year. Unfortunately, the models
are having a hard time coming to some agreement, which makes this,
unfortunately, a low confidence forecast. There is some higher
confidence for Tuesday, as a shortwave traversed the region in
northwest flow. This will bring better chances of precipitation to
the Cascades, and the higher terrain of northeast Washington and
the Idaho Panhandle. It was happens after Tuesday where things get
all mucked up. The Euro model has stuck to its guns, carving out a
larger trough over much of the US, keeping the Inland Northwest on
the western edge of the cold air mass. The GFS keeps any
influence of the cold air mass well to the east, instead building
a ridge of high pressure over the region. This ridge is more
amplified than it`s previous solutions. So, all in all, we didn`t
stray much from the previous forecasts, which weighted towards the
more consistent solution (colder). While this would bring snow
levels into the valleys, the north-northwesterly flow does not
look like it will have a ton of moisture to work with. Lots of
fine-tuning will be made to this portion of the forecast for sure.
ty

&&

.AVIATION...
18Z TAFS: A WEAK FRONTAL BOUNDARY WILL CONTINUE TO LIFT TO THE
NORTHEAST THIS MORNING...MOVING OUT OF THE KGEG/KPUW/KLWS TAF
SITES BY 20Z. HOWEVER...THE BOUNDARY LAYER REMAINS VERY MOIST AND
A STRONG INVERSION ALOFT REMAINS OVER THE AREA. MVFR AND SOME IFR
CEILINGS WILL REMAIN AT MOST TAF SITES EXCEPT KLWS AND KEAT
THROUGH THE NEXT 24 HOURS. A SECOND WEAK DISTURBANCE WILL TRANSIT
THE REGION BETWEEN 12Z AND 18Z FRIDAY MAINLY THREATENING THE KGEG
AREA TAF SITES WITH -SN. THERE IS A POSSIBILITY OF THIS
PRECIPITATION MANIFESTING ITSELF AS -FZRA THOUGH AT THIS TIME
CONFIDENCE IS LOW. /MJF


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        28  37  36  43  30  40 /  20  30 100  30  20  60
Coeur d`Alene  30  39  36  42  31  39 /  30  50 100  50  30  70
Pullman        29  41  36  43  34  42 /  10  10 100  70  40  60
Lewiston       32  44  40  48  36  47 /  10  10 100  70  30  50
Colville       25  37  34  44  20  38 /  30  70 100  50  10  60
Sandpoint      29  37  35  41  29  37 /  50  70 100  70  30  70
Kellogg        31  37  36  39  32  36 /  40  50 100  80  60  80
Moses Lake     24  36  35  48  30  46 /  10  50 100  10  10  30
Wenatchee      30  35  35  47  34  45 /  10  80 100  10  10  40
Omak           30  35  33  45  27  39 /  10  90 100  20  10  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon Friday to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northeast Mountains.

&&

$$





000
FXUS66 KOTX 202219
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
218 PM PST THU NOV 20 2014

.SYNOPSIS...
A relatively quiet and cool overnight period with a few snow
showers over the north will give way to a sharp deterioration in
the weather on Friday as a strong and moist Pacific storm brings
valley rain and mountain snow Friday night followed by very windy
conditions on Saturday. An active and periodically wet weather
regime will continue through the next week.

&&

.DISCUSSION...
Tonight...A rather mushy but somewhat benign night is in store
fro the region. Satellite and radar indicate the exiting storm
band that brought light snow to the region on track to move off
to the east early this evening. Meanwhile the next minor trough is
diving into California with a weak northern branch wave scuttling
into southern British Columbia. Models suggest a weak and
shearing wave will exist between these two dynamic centers and
will transit the region tonight...but the weakening nature of this
system should bring little beyond a few snow showers concentrated
over the northeastern zones late tonight. Once again fog and the
potential fro some freezing drizzle will exist in the deep basin
where stubborn arctic air is pooling in these low elevations.

Friday through Saturday...Latest models are in good agreement and
consistent with bringing a very moist and very dynamic wave
through the region during this period. A strong warm front will
make short work of the leftover and now modified arctic air over
the eastern half of the forecast area with snow levels expected to
rise to the 4000 foot region. In the west the cold air will be
slower to scrub and snow levels will stay low through much of this
event...perhaps all of it in the northern Cascade valleys and the
Okanogan valley. Snow levels will rise...but not as aggressively
over the southern portions of the deep basin...leading to the
likelihood of at least minimal warning criteria accumulating snow
on the Waterville Plateau. The southern valleys such as the
Wenatchee River valley will see some snow but amounts will be
overall fairly light. The Cascade mountains above 3000 to 4000
feet will get hammered with snow with a 12 hour period of moist
isentropic lift augmented by upslope southeasterly low level flow.
All the existing Winter Storm Watches will be upgraded to warnings
with the afternoon package...as well as adding the Okanogan and
Waterville Plateau to the highlight mix.

Beginning Friday morning the isentropic moistening process
will promote increasing clouds...with light snow beginning over
the northern zones in the early afternoon. By Friday evening an
almost universal field of valley rain and mountain snow will
envelop the region...except for the aforementioned north
Cascades/Okanogan where snow will continue as the dominant
meteor.

A strong cold front will rip through the region Saturday morning
largely ending precipitation in the Cascades lee but promoting
enhanced upslope snow showers into the Idaho Panhandle mountains.
The big story on Saturday will be very windy conditions especially
over the eastern basin exposed terrain with gust potential picked
off of model sounding mixed layers up to 45 or 50 mph. Saturday
will be a well mixed day with much milder temperatures than we
have grown accustomed to. /Fugazzi

Saturday Night through Monday Night: In the wake of Saturday`s
cold front, the breezy afternoon winds will gradually subside
overnight. Don`t see a great push of dry air behind this front. We
should have clearing skies in most places. This will allow
temperatures to drop sharply, especially in the northern valleys.
Then fog and stratus will form overnight and persist into Sunday
morning. The northwesterly flow is very unstable so the Panhandle
mountains will continue to pile up snow Saturday night.

By Sunday, another Pacific system will quickly clip across the
area. Due to the strong westerly flow, the Cascades and Panhandle
will be favored with this system. Spokane metro area could see
a little snow Sunday morning but will change to rain in the
afternoon.

Confidence is much lower for Monday`s event. The models really
diverge from each other on track and timing so I have about as
much chance of being wrong as right on the forecast. Went with
likely wording for the Cascades/Panhandle and chance wording
elsewhere. As usual, Highway 2/I-90 will be the dividing line
between rain and snow.  RJ

Tuesday through Thanksgiving: This portion of the forecast is
quite complicated, which is important because it envelops one of
the busiest travels days of the year. Unfortunately, the models
are having a hard time coming to some agreement, which makes this,
unfortunately, a low confidence forecast. There is some higher
confidence for Tuesday, as a shortwave traversed the region in
northwest flow. This will bring better chances of precipitation to
the Cascades, and the higher terrain of northeast Washington and
the Idaho Panhandle. It was happens after Tuesday where things get
all mucked up. The Euro model has stuck to its guns, carving out a
larger trough over much of the US, keeping the Inland Northwest on
the western edge of the cold air mass. The GFS keeps any
influence of the cold air mass well to the east, instead building
a ridge of high pressure over the region. This ridge is more
amplified than it`s previous solutions. So, all in all, we didn`t
stray much from the previous forecasts, which weighted towards the
more consistent solution (colder). While this would bring snow
levels into the valleys, the north-northwesterly flow does not
look like it will have a ton of moisture to work with. Lots of
fine-tuning will be made to this portion of the forecast for sure.
ty

&&

.AVIATION...
18Z TAFS: A WEAK FRONTAL BOUNDARY WILL CONTINUE TO LIFT TO THE
NORTHEAST THIS MORNING...MOVING OUT OF THE KGEG/KPUW/KLWS TAF
SITES BY 20Z. HOWEVER...THE BOUNDARY LAYER REMAINS VERY MOIST AND
A STRONG INVERSION ALOFT REMAINS OVER THE AREA. MVFR AND SOME IFR
CEILINGS WILL REMAIN AT MOST TAF SITES EXCEPT KLWS AND KEAT
THROUGH THE NEXT 24 HOURS. A SECOND WEAK DISTURBANCE WILL TRANSIT
THE REGION BETWEEN 12Z AND 18Z FRIDAY MAINLY THREATENING THE KGEG
AREA TAF SITES WITH -SN. THERE IS A POSSIBILITY OF THIS
PRECIPITATION MANIFESTING ITSELF AS -FZRA THOUGH AT THIS TIME
CONFIDENCE IS LOW. /MJF


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        28  37  36  43  30  40 /  20  30 100  30  20  60
Coeur d`Alene  30  39  36  42  31  39 /  30  50 100  50  30  70
Pullman        29  41  36  43  34  42 /  10  10 100  70  40  60
Lewiston       32  44  40  48  36  47 /  10  10 100  70  30  50
Colville       25  37  34  44  20  38 /  30  70 100  50  10  60
Sandpoint      29  37  35  41  29  37 /  50  70 100  70  30  70
Kellogg        31  37  36  39  32  36 /  40  50 100  80  60  80
Moses Lake     24  36  35  48  30  46 /  10  50 100  10  10  30
Wenatchee      30  35  35  47  34  45 /  10  80 100  10  10  40
Omak           30  35  33  45  27  39 /  10  90 100  20  10  40

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northern Panhandle.

     Winter Storm Warning from Noon Friday to 6 AM PST Sunday for
     Central Panhandle Mountains.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Warning from Noon Friday to 6 AM PST Saturday for
     East Slopes Northern Cascades-Okanogan Highlands-Okanogan
     Valley-Waterville Plateau.

     Winter Storm Warning from Noon Friday to 6 PM PST Saturday for
     Northeast Mountains.

&&

$$






000
FXUS66 KOTX 201756
AFDOTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
956 AM PST THU NOV 20 2014

.SYNOPSIS...
A WEAK WEATHER SYSTEM WILL PASS THROUGH TODAY WITH THE POTENTIAL
FOR A LIGHT WINTRY MIX OF RAIN...SNOW...AND FREEZING RAIN. A
STRONGER, WETTER AND WINDIER WEATHER SYSTEM WILL ARRIVE FRIDAY
PERSISTING INTO THE WEEKEND WITH HEAVY SNOW AMOUNTS POSSIBLE OVER
THE MOUNTAINS. THE WEATHER PATTERN WILL REMAIN ACTIVE THROUGH THE
MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
REST OF TODAY...THE WEAK WAVE WHICH BROUGHT A WINTRY MIX OF MINOR
PRECIPITATION TO THE AREA IS MAINLY IMPACTING THE NORTHEASTERN
ZONES AT 10AM AS IT SLOWLY MOVES OFF. THIS REGION OF NOW MAINLY
LIGHT SNOW WILL CONTINUE TO DEPOSIT LIGHT ACCUMULATIONS MAINLY TO
THE NORTHEASTERN ZONES AS IT MOVES INTO MONTANA LATER TODAY.

A SECOND AREA OF LIGHT PRECIPITATION IS MOVING INTO THE CASCADES
FROM THE WEST SIDE...BUT NOT MUCH OF THIS SYSTEM IS EXPECTED TO
SURVIVE THE TRIP ACROSS THE MOUNTAINS TODAY. HOWEVER...THE LOW
LEVEL AIR MASS REMAINS SATURATED THROUGH OUT THE REGION AND THIS
WILL PROMOTE AREAS OF FOG AND LOW CLOUDS THROUGH MUCH OF THE DAY
OVER MUCH OF THE REGION EVEN AFTER PRECIPITATION TAPERS OFF. THE
BEST CHANCE OF SUN WILL BE IN THE AREAS TUCKED AGAINST THE
CASCADES FROM WENATCHEE TO OMAK UNTIL HIGHER CLOUDS BLEEDING OVER
THE CASCADES STREAM IN AND FILTER THE SUN...MAYBE EVEN INCLUDING A
BRIEF SNOW SHOWER THIS AFTERNOON. MINOR UPDATES TO ZONE FORECASTS
ALREADY PUBLISHED. NO UPDATE TO STATE FORECAST PRODUCT
EXPECTED./FUGAZZI

&&

.AVIATION...
18Z TAFS: A WEAK FRONTAL BOUNDARY WILL CONTINUE TO LIFT TO THE
NORTHEAST THIS MORNING...MOVING OUT OF THE KGEG/KPUW/KLWS TAF
SITES BY 20Z. HOWEVER...THE BOUNDARY LAYER REMAINS VERY MOIST AND
A STRONG INVERSION ALOFT REMAINS OVER THE AREA. MVFR AND SOME IFR
CEILINGS WILL REMAIN AT MOST TAF SITES EXCEPT KLWS AND KEAT
THROUGH THE NEXT 24 HOURS. A SECOND WEAK DISTURBANCE WILL TRANSIT
THE REGION BETWEEN 12Z AND 18Z FRIDAY MAINLY THREATENING THE KGEG
AREA TAF SITES WITH -SN. THERE IS A POSSIBILITY OF THIS
PRECIPITATION MANIFESTING ITSELF AS -FZRA THOUGH AT THIS TIME
CONFIDECNE IS LOW. /MJF

&&

.PRELIMINARY POINT TEMPS/POPS...
SPOKANE        33  29  38  34  42  29 /  10  30  40 100  60  30
COEUR D`ALENE  33  29  40  33  41  31 /  30  50  50 100  70  30
PULLMAN        39  29  42  35  42  32 /  10  10  20 100  70  30
LEWISTON       41  32  45  39  47  35 /  10  10  10  80  50  30
COLVILLE       33  26  38  34  43  26 /  50  50  70 100  40  30
SANDPOINT      35  29  39  33  41  29 /  50  70  70 100  70  30
KELLOGG        35  30  39  32  39  32 /  70  50  60 100  90  40
MOSES LAKE     34  24  37  31  47  28 /  20  10  70 100  30  20
WENATCHEE      37  29  36  31  45  31 /  30  10  80 100  20  30
OMAK           34  26  37  30  43  27 /  20  10  90 100  20  30

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...AIR STAGNATION ADVISORY UNTIL NOON PST FRIDAY FOR CENTRAL
     PANHANDLE MOUNTAINS-COEUR D`ALENE AREA-IDAHO PALOUSE-
     NORTHERN PANHANDLE.

     WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY
     AFTERNOON FOR CENTRAL PANHANDLE MOUNTAINS-NORTHERN
     PANHANDLE.

WA...AIR STAGNATION ADVISORY UNTIL NOON PST FRIDAY FOR EAST SLOPES
     NORTHERN CASCADES-LOWER GARFIELD AND ASOTIN COUNTIES-MOSES
     LAKE AREA-NORTHEAST MOUNTAINS-OKANOGAN HIGHLANDS-SPOKANE
     AREA-UPPER COLUMBIA BASIN-WASHINGTON PALOUSE-WATERVILLE
     PLATEAU-WENATCHEE AREA.

     WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY
     AFTERNOON FOR NORTHEAST MOUNTAINS-OKANOGAN HIGHLANDS.

     WINTER STORM WATCH FROM FRIDAY MORNING THROUGH LATE FRIDAY NIGHT
     FOR EAST SLOPES NORTHERN CASCADES.

&&

$$




000
FXUS66 KOTX 201756
AFDOTX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
956 AM PST THU NOV 20 2014

.SYNOPSIS...
A WEAK WEATHER SYSTEM WILL PASS THROUGH TODAY WITH THE POTENTIAL
FOR A LIGHT WINTRY MIX OF RAIN...SNOW...AND FREEZING RAIN. A
STRONGER, WETTER AND WINDIER WEATHER SYSTEM WILL ARRIVE FRIDAY
PERSISTING INTO THE WEEKEND WITH HEAVY SNOW AMOUNTS POSSIBLE OVER
THE MOUNTAINS. THE WEATHER PATTERN WILL REMAIN ACTIVE THROUGH THE
MIDDLE OF NEXT WEEK.

&&

.DISCUSSION...
REST OF TODAY...THE WEAK WAVE WHICH BROUGHT A WINTRY MIX OF MINOR
PRECIPITATION TO THE AREA IS MAINLY IMPACTING THE NORTHEASTERN
ZONES AT 10AM AS IT SLOWLY MOVES OFF. THIS REGION OF NOW MAINLY
LIGHT SNOW WILL CONTINUE TO DEPOSIT LIGHT ACCUMULATIONS MAINLY TO
THE NORTHEASTERN ZONES AS IT MOVES INTO MONTANA LATER TODAY.

A SECOND AREA OF LIGHT PRECIPITATION IS MOVING INTO THE CASCADES
FROM THE WEST SIDE...BUT NOT MUCH OF THIS SYSTEM IS EXPECTED TO
SURVIVE THE TRIP ACROSS THE MOUNTAINS TODAY. HOWEVER...THE LOW
LEVEL AIR MASS REMAINS SATURATED THROUGH OUT THE REGION AND THIS
WILL PROMOTE AREAS OF FOG AND LOW CLOUDS THROUGH MUCH OF THE DAY
OVER MUCH OF THE REGION EVEN AFTER PRECIPITATION TAPERS OFF. THE
BEST CHANCE OF SUN WILL BE IN THE AREAS TUCKED AGAINST THE
CASCADES FROM WENATCHEE TO OMAK UNTIL HIGHER CLOUDS BLEEDING OVER
THE CASCADES STREAM IN AND FILTER THE SUN...MAYBE EVEN INCLUDING A
BRIEF SNOW SHOWER THIS AFTERNOON. MINOR UPDATES TO ZONE FORECASTS
ALREADY PUBLISHED. NO UPDATE TO STATE FORECAST PRODUCT
EXPECTED./FUGAZZI

&&

.AVIATION...
18Z TAFS: A WEAK FRONTAL BOUNDARY WILL CONTINUE TO LIFT TO THE
NORTHEAST THIS MORNING...MOVING OUT OF THE KGEG/KPUW/KLWS TAF
SITES BY 20Z. HOWEVER...THE BOUNDARY LAYER REMAINS VERY MOIST AND
A STRONG INVERSION ALOFT REMAINS OVER THE AREA. MVFR AND SOME IFR
CEILINGS WILL REMAIN AT MOST TAF SITES EXCEPT KLWS AND KEAT
THROUGH THE NEXT 24 HOURS. A SECOND WEAK DISTURBANCE WILL TRANSIT
THE REGION BETWEEN 12Z AND 18Z FRIDAY MAINLY THREATENING THE KGEG
AREA TAF SITES WITH -SN. THERE IS A POSSIBILITY OF THIS
PRECIPITATION MANIFESTING ITSELF AS -FZRA THOUGH AT THIS TIME
CONFIDECNE IS LOW. /MJF

&&

.PRELIMINARY POINT TEMPS/POPS...
SPOKANE        33  29  38  34  42  29 /  10  30  40 100  60  30
COEUR D`ALENE  33  29  40  33  41  31 /  30  50  50 100  70  30
PULLMAN        39  29  42  35  42  32 /  10  10  20 100  70  30
LEWISTON       41  32  45  39  47  35 /  10  10  10  80  50  30
COLVILLE       33  26  38  34  43  26 /  50  50  70 100  40  30
SANDPOINT      35  29  39  33  41  29 /  50  70  70 100  70  30
KELLOGG        35  30  39  32  39  32 /  70  50  60 100  90  40
MOSES LAKE     34  24  37  31  47  28 /  20  10  70 100  30  20
WENATCHEE      37  29  36  31  45  31 /  30  10  80 100  20  30
OMAK           34  26  37  30  43  27 /  20  10  90 100  20  30

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...AIR STAGNATION ADVISORY UNTIL NOON PST FRIDAY FOR CENTRAL
     PANHANDLE MOUNTAINS-COEUR D`ALENE AREA-IDAHO PALOUSE-
     NORTHERN PANHANDLE.

     WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY
     AFTERNOON FOR CENTRAL PANHANDLE MOUNTAINS-NORTHERN
     PANHANDLE.

WA...AIR STAGNATION ADVISORY UNTIL NOON PST FRIDAY FOR EAST SLOPES
     NORTHERN CASCADES-LOWER GARFIELD AND ASOTIN COUNTIES-MOSES
     LAKE AREA-NORTHEAST MOUNTAINS-OKANOGAN HIGHLANDS-SPOKANE
     AREA-UPPER COLUMBIA BASIN-WASHINGTON PALOUSE-WATERVILLE
     PLATEAU-WENATCHEE AREA.

     WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY
     AFTERNOON FOR NORTHEAST MOUNTAINS-OKANOGAN HIGHLANDS.

     WINTER STORM WATCH FROM FRIDAY MORNING THROUGH LATE FRIDAY NIGHT
     FOR EAST SLOPES NORTHERN CASCADES.

&&

$$





000
FXUS66 KOTX 201320
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
520 AM PST THU NOV 20 2014

.SYNOPSIS...
A weak weather system will arrive late tonight into Thursday with
the potential for a light wintry mix of rain...snow...and freezing
rain. A stronger, wetter and windier weather system will arrive
Friday persisting into the weekend with heavy snow amounts
possible over the mountains. The weather pattern will remain
active through the middle of next week.



&&

.DISCUSSION...

...Pockets of freezing rain possible this morning over the lower
Columbia Basin and portions of the Washington Palouse...

Today and tonight ...The ridge of the past week and a half is
becoming a relic of the past as disturbance number one (of many)
is currently passing through western Washington with its sights
set on the Inland Northwest. This disturbance is comprised of an
elongating band of moisture extending from a weak upper level low
just west of Vancouver Island southeast into in southwest Idaho.
Associated with this band of moisture was a weakening warm front
which will provide the focus for the weather today. Models have
remained rather consistent in taking this front from its current
position over south-central Washington northeast across the
remainder of eastern Washington and north Idaho today. The trend
of slowing the front continues...and now it looks like the front
won`t arrive into the northern tip of Idaho until around midday.

Forcing and lifting along the front looks rather weak...and it will
likely continue to diminish as it treks northeastward today.
Nonetheless...with a modified arctic air mass still firmly
entrenched over most of the region...it won`t take much lifting to
generate precipitation as the isentropic surfaces look rather
steep. That suggests most of the region will be subject to
precipitation today...but the question is what will it fall as.
This remains an exceedingly tricky forecast element. Model cross-
sections and 0-4km max wet-bulb temperatures continue to show an
elevated wedge of above freezing air over the extreme southern
portion of our forecast area. This encompasses the area generally
south of a line from Wenatchee to Moses Lake...then Pullman. Any
locations south of this line will be subject to light freezing
rain (with a small chance of sleet)...through this morning.
Meanwhile anything north will generally see snow. Again amounts
will be fairly light. Through the end of the day most locations
will see an tenth of an inch of precipitation or less. Snow
amounts will reflect this light precipitation with locations
generally seeing less than an inch. As for the freezing
rain...amounts will also be light...however any freezing rain can
result in potential travel difficulties. The potential for travel
problems will generally be confined to the morning hours as any
diurnal heating should bring road temperatures above freezing by
midday. Additionally...most of the precipitation threat also move
north and east of this elevated warm layer as well.

The front is expected to dissipate rapidly during the
evening...but that won`t be the end of the precipitation.
Initially upslope flow and residual frontal moisture will keep the
light snow falling over north Idaho...however things will
intensify somewhat overnight. This next round of precipitation
will be delivered care of the shortwave trough off of Vancouver
Island tracking through southern British Columbia overnight. The
lifting associated with this feature will not be strong...however
the atmosphere below 650 mbs or roughly 10k feet will become
saturated overnight. Renewed isentropic ascent...especially for
locations north of Highway 2 (in Washington) and I-90 (in
Idaho)...should result in a second round of precipitation. The
warm layer will surge a little farther north as well. By
morning...a shallow elevated melting layer could move as far north
as a Lake Chelan to Spokane line. This will be on the southern
edge of the next round of precipitation so there`s a small chance
of more freezing rain...however by that time...surface wet-bulb
temperatures are expected to near or exceed freezing...so main
precipitation would be rain or a rain snow mix for the Spokane
area and southeast sections of the Columbia Basin. For locations
over the northwest portion of the Basin...including Grand
Coulee...Wilbur...and Davenport there will be a small chance of
freezing rain. Confidence is not high however...as so much is
dependent on what happens today in terms of surface warming. If a
location gets above freezing today...it will likely remain that
way overnight as well. fx


...MODERATE TO HEAVY MOUNTAIN SNOW POSSIBLE LATE FRIDAY INTO
SATURDAY...

Friday through Monday: A series of systems slide across the
Inland NW, with several opportunities for rain and snow. First
early Friday the next system will be approaching. There will be a
threat of light snow or freezing rain/freezing drizzle across the
Upper Columbia Basin through northeast WA and north ID due to some
isentropic lift and low level moisture. The moisture is deepest
below about 650 to 700 mbs, below the core of the snow growth
zone. So this suggest the potential for a mixture of snow,
freezing rain or freezing drizzle, and rain as the precipitation
type. So we could be looking for some slick conditions along the
I-90/US-2/US-95 corridor in the morning.

Then Friday afternoon into Friday evening deepening isentropic
ascent and moisture noses across the Cascades into eastern WA and
north ID with the warm front. This will lead to increasing
precipitation from west to east, so that by early evening most of
Washington will be enveloped by it and by middle to late evening
much of Idaho will be too. Overnight the associated cold front
slips east of the Cascades, leading to dwindling precipitation in
the lee of the Cascades and western Columbia Basin. By late
Saturday morning to afternoon the highest threat briefly retreats
to the mountains, with winds becoming breezy to locally windy.
With the evolution discussed, the next questions surround snow
levels and precipitation amounts.

* Snow levels: The location of the snow hasn`t changed much from
  previous thinking. Based on wet-bulb zero heights, snow levels
  from Friday afternoon through Friday night will be around
  3000-4000 feet across the Cascades and northern mountains and
  4000 to 5000 feet southeast. However colder air trapped near the
  Cascades in the low level southeast flow will keep snow levels
  1500-3000 feet. This includes places in the lee of the Cascades,
  including the Okanogan Valley and Highlands through the
  Waterville Plateau and Wenatchee area. So the Cascades and areas
  the remaining mountain areas above 3000 to 4000 feet (except for
  the Blue Mountains where snow levels look too high to have much
  impact in the populated areas). Winter storm watches
  remain place for the Cascades and in the north WA and ID
  mountains above 4000 feet. We will monitor the potential need
  for advisories outside of the mountains, in the hills around the
  Okanogan Valley and Waterville Plateau and Wenatchee area.
  However accumulations may be limited if milder air is able to
  move in or precipitation amounts are not as high as expected.
  Behind the cold front going into Saturday afternoon snow levels
  drop to between 2500-3000 feet. So this means any lingering
  showers may be a mix of rain and snow, including as far south as
  the I-90 corridor. However by then the better precipitation
  threat starts that shift into the mountains.

* Precipitation amounts: Regional PWATs rise to between 0.45 to
  0.75 inches (or 130 to 200% of normal). So this is a juicy
  system and all models generate decent precipitation amounts. In
  the 24-hour period between Friday afternoon and Saturday
  afternoon models generate between 0.30 to 0.60 inches of liquid
  precipitation across a good portion of the Inland NW, with lower
  amounts over the deeper Columbia Basin and higher amounts
  between 0.75 to 1.0 inch in the mountains. For areas the
  mountain snow this could translate to between 6 to 12 inches,
  while the lower elevations closer to the Cascades could see
  anywhere from a trace to a couple inches or so. These numbers,
  especially the lower elevation ones, will continue to be fine-
  tuned.

From Saturday evening into Sunday morning a secondary disturbance
slips by, renewing the precipitation threat outside of the
mountains. However precipitation amount as compared to Friday
night, look light. A third and more organized system comes in
sometime between Sunday and Monday morning. This taps some
subtropical moisture, but it is not as robust as the Friday night
system. Still models generate a modest precipitation threat across
all but the lee of the Cascades and deeper Basin. When and where
this develops is where model disagreement lingers. Most models
start precipitation early Sunday near Cascades. Yet farther east
some start it up through southeast WA and the central Panhandle in
the morning and others hold it off until afternoon. Chances remain
high outside of the lee of the Cascades and deeper Columbia Basin
through the evening, then dissipate overnight into Monday. Still
the leading edge of a fourth system, a warm front, approaches from
the west Monday afternoon. Whether moisture is deep enough to
allow precipitation to redevelop or just thickening clouds is even
less agreed upon. Chances will remain high near the Cascades and
lower elsewhere. As for snow levels through the period from
Saturday night through Monday, they waver between about 1500 and
3000 feet during the night and early morning hours and 2000 and
4000 feet during the day and early evening hours. The lowest of
those lay toward the northeast WA and north ID. This translates to
the potential for snow down to valley floors, especially at night,
and perhaps some light accumulations in the valleys. This includes
potentially the I-90 corridor, especially east of Ritzville and
the higher Palouse, as well as areas from the Waterville Plateau
north. /J. Cote`

Monday Night through Thursday: Pattern looks to remain active
early in the week as the moist northwesterly flow continues to
influence our weather. Exactly how long we remain active is up for
debate amongst the models at this point. The GFS brings an
offshore ridge near the west coast shifting the majority of the
atmospheric dynamics and moisture to the north ultimately leading
to a drier forecast. The ECMWF with support from the Canadian
model keeps the ridge further offshore and the opportunity for
precipitation alive much later into the week. At this point I have
leaned toward the Euro due to performance up to this point with
winter systems and kept POPs above climo through Wednesday. Along
with precip into the middle of the week, the Euro also brings
another round of cold continental polar air into the region
starting Wednesday sending our temperatures back below normal. In
turn the temperatures were trended down, but not yet to the full
extent of the ECMWF as I want just a bit more confidence. The
polar airmass is also quite dry so once the modified polar front
passes Wednesday, POPs drop off as well. Snow levels with the
precipitation in the extended forecast once again looks to sit
above most valley floors minus the far northern ones leading to
mainly a valley rain/mountain snow event. Higher benches such as
the West Plains, Upper Columbia Basin, etc. could see some snow
mix in overnight as our diurnal swings bottoms out. While this
forecast leaned more towards the Euro, model trends will have to
be closely monitored to better pin down the details as we near
this timeframe. /Fliehman

&&

.AVIATION...
12Z TAFS: A weak frontal boundary will continue to lift to the
northeast this morning potentially impacting all forecast sites.
The threat will exit MWH and EAT by 15z and the other sites
between 17-19z. While vsbys and cigs will generally be in the VFR
category...brief MVFR conditions will be possible but not worth
mentioning in forecast. The most difficult part of the forecast is
what will the precipitation fall as. Based on elevated melting
layer and temperatures near or below freezing at all sites...a
winter mix is expected with the best chances of freezing rain
expected for PUW and MWH. Confidence is low though as this is a
very complex situation. The front will exit the area...with dry
weather for most sites afterwords. Later tonight another round of
precipitation arrives late tonight (after 08z) and this will
mainly impact GEG- SFF- COE. Suspect this round will mainly be
rain...but that is far from certain. fx

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        34  31  38  34  42  29 /  50  30  40 100  60  30
Coeur d`Alene  34  32  40  33  41  31 /  70  40  50 100  70  30
Pullman        39  29  42  35  42  32 /  60  10  20 100  70  30
Lewiston       40  31  45  39  47  35 /  80  10  10  80  50  30
Colville       34  26  38  34  43  26 /  50  40  70 100  40  30
Sandpoint      34  30  39  33  41  29 /  60  70  70 100  70  30
Kellogg        34  31  39  32  39  32 /  90  60  60 100  90  40
Moses Lake     35  21  37  31  47  28 /  60   0  70 100  30  20
Wenatchee      39  28  36  31  45  31 /  70   0  80 100  20  30
Omak           36  27  37  30  43  27 /  50  20  90 100  20  30

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Central Panhandle Mountains-Northern
     Panhandle.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Northeast Mountains-Okanogan Highlands.

     Winter Storm Watch from Friday morning through late Friday night
     for East Slopes Northern Cascades.

&&

$$





000
FXUS66 KOTX 201320
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
520 AM PST THU NOV 20 2014

.SYNOPSIS...
A weak weather system will arrive late tonight into Thursday with
the potential for a light wintry mix of rain...snow...and freezing
rain. A stronger, wetter and windier weather system will arrive
Friday persisting into the weekend with heavy snow amounts
possible over the mountains. The weather pattern will remain
active through the middle of next week.



&&

.DISCUSSION...

...Pockets of freezing rain possible this morning over the lower
Columbia Basin and portions of the Washington Palouse...

Today and tonight ...The ridge of the past week and a half is
becoming a relic of the past as disturbance number one (of many)
is currently passing through western Washington with its sights
set on the Inland Northwest. This disturbance is comprised of an
elongating band of moisture extending from a weak upper level low
just west of Vancouver Island southeast into in southwest Idaho.
Associated with this band of moisture was a weakening warm front
which will provide the focus for the weather today. Models have
remained rather consistent in taking this front from its current
position over south-central Washington northeast across the
remainder of eastern Washington and north Idaho today. The trend
of slowing the front continues...and now it looks like the front
won`t arrive into the northern tip of Idaho until around midday.

Forcing and lifting along the front looks rather weak...and it will
likely continue to diminish as it treks northeastward today.
Nonetheless...with a modified arctic air mass still firmly
entrenched over most of the region...it won`t take much lifting to
generate precipitation as the isentropic surfaces look rather
steep. That suggests most of the region will be subject to
precipitation today...but the question is what will it fall as.
This remains an exceedingly tricky forecast element. Model cross-
sections and 0-4km max wet-bulb temperatures continue to show an
elevated wedge of above freezing air over the extreme southern
portion of our forecast area. This encompasses the area generally
south of a line from Wenatchee to Moses Lake...then Pullman. Any
locations south of this line will be subject to light freezing
rain (with a small chance of sleet)...through this morning.
Meanwhile anything north will generally see snow. Again amounts
will be fairly light. Through the end of the day most locations
will see an tenth of an inch of precipitation or less. Snow
amounts will reflect this light precipitation with locations
generally seeing less than an inch. As for the freezing
rain...amounts will also be light...however any freezing rain can
result in potential travel difficulties. The potential for travel
problems will generally be confined to the morning hours as any
diurnal heating should bring road temperatures above freezing by
midday. Additionally...most of the precipitation threat also move
north and east of this elevated warm layer as well.

The front is expected to dissipate rapidly during the
evening...but that won`t be the end of the precipitation.
Initially upslope flow and residual frontal moisture will keep the
light snow falling over north Idaho...however things will
intensify somewhat overnight. This next round of precipitation
will be delivered care of the shortwave trough off of Vancouver
Island tracking through southern British Columbia overnight. The
lifting associated with this feature will not be strong...however
the atmosphere below 650 mbs or roughly 10k feet will become
saturated overnight. Renewed isentropic ascent...especially for
locations north of Highway 2 (in Washington) and I-90 (in
Idaho)...should result in a second round of precipitation. The
warm layer will surge a little farther north as well. By
morning...a shallow elevated melting layer could move as far north
as a Lake Chelan to Spokane line. This will be on the southern
edge of the next round of precipitation so there`s a small chance
of more freezing rain...however by that time...surface wet-bulb
temperatures are expected to near or exceed freezing...so main
precipitation would be rain or a rain snow mix for the Spokane
area and southeast sections of the Columbia Basin. For locations
over the northwest portion of the Basin...including Grand
Coulee...Wilbur...and Davenport there will be a small chance of
freezing rain. Confidence is not high however...as so much is
dependent on what happens today in terms of surface warming. If a
location gets above freezing today...it will likely remain that
way overnight as well. fx


...MODERATE TO HEAVY MOUNTAIN SNOW POSSIBLE LATE FRIDAY INTO
SATURDAY...

Friday through Monday: A series of systems slide across the
Inland NW, with several opportunities for rain and snow. First
early Friday the next system will be approaching. There will be a
threat of light snow or freezing rain/freezing drizzle across the
Upper Columbia Basin through northeast WA and north ID due to some
isentropic lift and low level moisture. The moisture is deepest
below about 650 to 700 mbs, below the core of the snow growth
zone. So this suggest the potential for a mixture of snow,
freezing rain or freezing drizzle, and rain as the precipitation
type. So we could be looking for some slick conditions along the
I-90/US-2/US-95 corridor in the morning.

Then Friday afternoon into Friday evening deepening isentropic
ascent and moisture noses across the Cascades into eastern WA and
north ID with the warm front. This will lead to increasing
precipitation from west to east, so that by early evening most of
Washington will be enveloped by it and by middle to late evening
much of Idaho will be too. Overnight the associated cold front
slips east of the Cascades, leading to dwindling precipitation in
the lee of the Cascades and western Columbia Basin. By late
Saturday morning to afternoon the highest threat briefly retreats
to the mountains, with winds becoming breezy to locally windy.
With the evolution discussed, the next questions surround snow
levels and precipitation amounts.

* Snow levels: The location of the snow hasn`t changed much from
  previous thinking. Based on wet-bulb zero heights, snow levels
  from Friday afternoon through Friday night will be around
  3000-4000 feet across the Cascades and northern mountains and
  4000 to 5000 feet southeast. However colder air trapped near the
  Cascades in the low level southeast flow will keep snow levels
  1500-3000 feet. This includes places in the lee of the Cascades,
  including the Okanogan Valley and Highlands through the
  Waterville Plateau and Wenatchee area. So the Cascades and areas
  the remaining mountain areas above 3000 to 4000 feet (except for
  the Blue Mountains where snow levels look too high to have much
  impact in the populated areas). Winter storm watches
  remain place for the Cascades and in the north WA and ID
  mountains above 4000 feet. We will monitor the potential need
  for advisories outside of the mountains, in the hills around the
  Okanogan Valley and Waterville Plateau and Wenatchee area.
  However accumulations may be limited if milder air is able to
  move in or precipitation amounts are not as high as expected.
  Behind the cold front going into Saturday afternoon snow levels
  drop to between 2500-3000 feet. So this means any lingering
  showers may be a mix of rain and snow, including as far south as
  the I-90 corridor. However by then the better precipitation
  threat starts that shift into the mountains.

* Precipitation amounts: Regional PWATs rise to between 0.45 to
  0.75 inches (or 130 to 200% of normal). So this is a juicy
  system and all models generate decent precipitation amounts. In
  the 24-hour period between Friday afternoon and Saturday
  afternoon models generate between 0.30 to 0.60 inches of liquid
  precipitation across a good portion of the Inland NW, with lower
  amounts over the deeper Columbia Basin and higher amounts
  between 0.75 to 1.0 inch in the mountains. For areas the
  mountain snow this could translate to between 6 to 12 inches,
  while the lower elevations closer to the Cascades could see
  anywhere from a trace to a couple inches or so. These numbers,
  especially the lower elevation ones, will continue to be fine-
  tuned.

From Saturday evening into Sunday morning a secondary disturbance
slips by, renewing the precipitation threat outside of the
mountains. However precipitation amount as compared to Friday
night, look light. A third and more organized system comes in
sometime between Sunday and Monday morning. This taps some
subtropical moisture, but it is not as robust as the Friday night
system. Still models generate a modest precipitation threat across
all but the lee of the Cascades and deeper Basin. When and where
this develops is where model disagreement lingers. Most models
start precipitation early Sunday near Cascades. Yet farther east
some start it up through southeast WA and the central Panhandle in
the morning and others hold it off until afternoon. Chances remain
high outside of the lee of the Cascades and deeper Columbia Basin
through the evening, then dissipate overnight into Monday. Still
the leading edge of a fourth system, a warm front, approaches from
the west Monday afternoon. Whether moisture is deep enough to
allow precipitation to redevelop or just thickening clouds is even
less agreed upon. Chances will remain high near the Cascades and
lower elsewhere. As for snow levels through the period from
Saturday night through Monday, they waver between about 1500 and
3000 feet during the night and early morning hours and 2000 and
4000 feet during the day and early evening hours. The lowest of
those lay toward the northeast WA and north ID. This translates to
the potential for snow down to valley floors, especially at night,
and perhaps some light accumulations in the valleys. This includes
potentially the I-90 corridor, especially east of Ritzville and
the higher Palouse, as well as areas from the Waterville Plateau
north. /J. Cote`

Monday Night through Thursday: Pattern looks to remain active
early in the week as the moist northwesterly flow continues to
influence our weather. Exactly how long we remain active is up for
debate amongst the models at this point. The GFS brings an
offshore ridge near the west coast shifting the majority of the
atmospheric dynamics and moisture to the north ultimately leading
to a drier forecast. The ECMWF with support from the Canadian
model keeps the ridge further offshore and the opportunity for
precipitation alive much later into the week. At this point I have
leaned toward the Euro due to performance up to this point with
winter systems and kept POPs above climo through Wednesday. Along
with precip into the middle of the week, the Euro also brings
another round of cold continental polar air into the region
starting Wednesday sending our temperatures back below normal. In
turn the temperatures were trended down, but not yet to the full
extent of the ECMWF as I want just a bit more confidence. The
polar airmass is also quite dry so once the modified polar front
passes Wednesday, POPs drop off as well. Snow levels with the
precipitation in the extended forecast once again looks to sit
above most valley floors minus the far northern ones leading to
mainly a valley rain/mountain snow event. Higher benches such as
the West Plains, Upper Columbia Basin, etc. could see some snow
mix in overnight as our diurnal swings bottoms out. While this
forecast leaned more towards the Euro, model trends will have to
be closely monitored to better pin down the details as we near
this timeframe. /Fliehman

&&

.AVIATION...
12Z TAFS: A weak frontal boundary will continue to lift to the
northeast this morning potentially impacting all forecast sites.
The threat will exit MWH and EAT by 15z and the other sites
between 17-19z. While vsbys and cigs will generally be in the VFR
category...brief MVFR conditions will be possible but not worth
mentioning in forecast. The most difficult part of the forecast is
what will the precipitation fall as. Based on elevated melting
layer and temperatures near or below freezing at all sites...a
winter mix is expected with the best chances of freezing rain
expected for PUW and MWH. Confidence is low though as this is a
very complex situation. The front will exit the area...with dry
weather for most sites afterwords. Later tonight another round of
precipitation arrives late tonight (after 08z) and this will
mainly impact GEG- SFF- COE. Suspect this round will mainly be
rain...but that is far from certain. fx

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        34  31  38  34  42  29 /  50  30  40 100  60  30
Coeur d`Alene  34  32  40  33  41  31 /  70  40  50 100  70  30
Pullman        39  29  42  35  42  32 /  60  10  20 100  70  30
Lewiston       40  31  45  39  47  35 /  80  10  10  80  50  30
Colville       34  26  38  34  43  26 /  50  40  70 100  40  30
Sandpoint      34  30  39  33  41  29 /  60  70  70 100  70  30
Kellogg        34  31  39  32  39  32 /  90  60  60 100  90  40
Moses Lake     35  21  37  31  47  28 /  60   0  70 100  30  20
Wenatchee      39  28  36  31  45  31 /  70   0  80 100  20  30
Omak           36  27  37  30  43  27 /  50  20  90 100  20  30

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Central Panhandle Mountains-Northern
     Panhandle.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Northeast Mountains-Okanogan Highlands.

     Winter Storm Watch from Friday morning through late Friday night
     for East Slopes Northern Cascades.

&&

$$





000
FXUS66 KOTX 201320
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
520 AM PST THU NOV 20 2014

.SYNOPSIS...
A weak weather system will arrive late tonight into Thursday with
the potential for a light wintry mix of rain...snow...and freezing
rain. A stronger, wetter and windier weather system will arrive
Friday persisting into the weekend with heavy snow amounts
possible over the mountains. The weather pattern will remain
active through the middle of next week.



&&

.DISCUSSION...

...Pockets of freezing rain possible this morning over the lower
Columbia Basin and portions of the Washington Palouse...

Today and tonight ...The ridge of the past week and a half is
becoming a relic of the past as disturbance number one (of many)
is currently passing through western Washington with its sights
set on the Inland Northwest. This disturbance is comprised of an
elongating band of moisture extending from a weak upper level low
just west of Vancouver Island southeast into in southwest Idaho.
Associated with this band of moisture was a weakening warm front
which will provide the focus for the weather today. Models have
remained rather consistent in taking this front from its current
position over south-central Washington northeast across the
remainder of eastern Washington and north Idaho today. The trend
of slowing the front continues...and now it looks like the front
won`t arrive into the northern tip of Idaho until around midday.

Forcing and lifting along the front looks rather weak...and it will
likely continue to diminish as it treks northeastward today.
Nonetheless...with a modified arctic air mass still firmly
entrenched over most of the region...it won`t take much lifting to
generate precipitation as the isentropic surfaces look rather
steep. That suggests most of the region will be subject to
precipitation today...but the question is what will it fall as.
This remains an exceedingly tricky forecast element. Model cross-
sections and 0-4km max wet-bulb temperatures continue to show an
elevated wedge of above freezing air over the extreme southern
portion of our forecast area. This encompasses the area generally
south of a line from Wenatchee to Moses Lake...then Pullman. Any
locations south of this line will be subject to light freezing
rain (with a small chance of sleet)...through this morning.
Meanwhile anything north will generally see snow. Again amounts
will be fairly light. Through the end of the day most locations
will see an tenth of an inch of precipitation or less. Snow
amounts will reflect this light precipitation with locations
generally seeing less than an inch. As for the freezing
rain...amounts will also be light...however any freezing rain can
result in potential travel difficulties. The potential for travel
problems will generally be confined to the morning hours as any
diurnal heating should bring road temperatures above freezing by
midday. Additionally...most of the precipitation threat also move
north and east of this elevated warm layer as well.

The front is expected to dissipate rapidly during the
evening...but that won`t be the end of the precipitation.
Initially upslope flow and residual frontal moisture will keep the
light snow falling over north Idaho...however things will
intensify somewhat overnight. This next round of precipitation
will be delivered care of the shortwave trough off of Vancouver
Island tracking through southern British Columbia overnight. The
lifting associated with this feature will not be strong...however
the atmosphere below 650 mbs or roughly 10k feet will become
saturated overnight. Renewed isentropic ascent...especially for
locations north of Highway 2 (in Washington) and I-90 (in
Idaho)...should result in a second round of precipitation. The
warm layer will surge a little farther north as well. By
morning...a shallow elevated melting layer could move as far north
as a Lake Chelan to Spokane line. This will be on the southern
edge of the next round of precipitation so there`s a small chance
of more freezing rain...however by that time...surface wet-bulb
temperatures are expected to near or exceed freezing...so main
precipitation would be rain or a rain snow mix for the Spokane
area and southeast sections of the Columbia Basin. For locations
over the northwest portion of the Basin...including Grand
Coulee...Wilbur...and Davenport there will be a small chance of
freezing rain. Confidence is not high however...as so much is
dependent on what happens today in terms of surface warming. If a
location gets above freezing today...it will likely remain that
way overnight as well. fx


...MODERATE TO HEAVY MOUNTAIN SNOW POSSIBLE LATE FRIDAY INTO
SATURDAY...

Friday through Monday: A series of systems slide across the
Inland NW, with several opportunities for rain and snow. First
early Friday the next system will be approaching. There will be a
threat of light snow or freezing rain/freezing drizzle across the
Upper Columbia Basin through northeast WA and north ID due to some
isentropic lift and low level moisture. The moisture is deepest
below about 650 to 700 mbs, below the core of the snow growth
zone. So this suggest the potential for a mixture of snow,
freezing rain or freezing drizzle, and rain as the precipitation
type. So we could be looking for some slick conditions along the
I-90/US-2/US-95 corridor in the morning.

Then Friday afternoon into Friday evening deepening isentropic
ascent and moisture noses across the Cascades into eastern WA and
north ID with the warm front. This will lead to increasing
precipitation from west to east, so that by early evening most of
Washington will be enveloped by it and by middle to late evening
much of Idaho will be too. Overnight the associated cold front
slips east of the Cascades, leading to dwindling precipitation in
the lee of the Cascades and western Columbia Basin. By late
Saturday morning to afternoon the highest threat briefly retreats
to the mountains, with winds becoming breezy to locally windy.
With the evolution discussed, the next questions surround snow
levels and precipitation amounts.

* Snow levels: The location of the snow hasn`t changed much from
  previous thinking. Based on wet-bulb zero heights, snow levels
  from Friday afternoon through Friday night will be around
  3000-4000 feet across the Cascades and northern mountains and
  4000 to 5000 feet southeast. However colder air trapped near the
  Cascades in the low level southeast flow will keep snow levels
  1500-3000 feet. This includes places in the lee of the Cascades,
  including the Okanogan Valley and Highlands through the
  Waterville Plateau and Wenatchee area. So the Cascades and areas
  the remaining mountain areas above 3000 to 4000 feet (except for
  the Blue Mountains where snow levels look too high to have much
  impact in the populated areas). Winter storm watches
  remain place for the Cascades and in the north WA and ID
  mountains above 4000 feet. We will monitor the potential need
  for advisories outside of the mountains, in the hills around the
  Okanogan Valley and Waterville Plateau and Wenatchee area.
  However accumulations may be limited if milder air is able to
  move in or precipitation amounts are not as high as expected.
  Behind the cold front going into Saturday afternoon snow levels
  drop to between 2500-3000 feet. So this means any lingering
  showers may be a mix of rain and snow, including as far south as
  the I-90 corridor. However by then the better precipitation
  threat starts that shift into the mountains.

* Precipitation amounts: Regional PWATs rise to between 0.45 to
  0.75 inches (or 130 to 200% of normal). So this is a juicy
  system and all models generate decent precipitation amounts. In
  the 24-hour period between Friday afternoon and Saturday
  afternoon models generate between 0.30 to 0.60 inches of liquid
  precipitation across a good portion of the Inland NW, with lower
  amounts over the deeper Columbia Basin and higher amounts
  between 0.75 to 1.0 inch in the mountains. For areas the
  mountain snow this could translate to between 6 to 12 inches,
  while the lower elevations closer to the Cascades could see
  anywhere from a trace to a couple inches or so. These numbers,
  especially the lower elevation ones, will continue to be fine-
  tuned.

From Saturday evening into Sunday morning a secondary disturbance
slips by, renewing the precipitation threat outside of the
mountains. However precipitation amount as compared to Friday
night, look light. A third and more organized system comes in
sometime between Sunday and Monday morning. This taps some
subtropical moisture, but it is not as robust as the Friday night
system. Still models generate a modest precipitation threat across
all but the lee of the Cascades and deeper Basin. When and where
this develops is where model disagreement lingers. Most models
start precipitation early Sunday near Cascades. Yet farther east
some start it up through southeast WA and the central Panhandle in
the morning and others hold it off until afternoon. Chances remain
high outside of the lee of the Cascades and deeper Columbia Basin
through the evening, then dissipate overnight into Monday. Still
the leading edge of a fourth system, a warm front, approaches from
the west Monday afternoon. Whether moisture is deep enough to
allow precipitation to redevelop or just thickening clouds is even
less agreed upon. Chances will remain high near the Cascades and
lower elsewhere. As for snow levels through the period from
Saturday night through Monday, they waver between about 1500 and
3000 feet during the night and early morning hours and 2000 and
4000 feet during the day and early evening hours. The lowest of
those lay toward the northeast WA and north ID. This translates to
the potential for snow down to valley floors, especially at night,
and perhaps some light accumulations in the valleys. This includes
potentially the I-90 corridor, especially east of Ritzville and
the higher Palouse, as well as areas from the Waterville Plateau
north. /J. Cote`

Monday Night through Thursday: Pattern looks to remain active
early in the week as the moist northwesterly flow continues to
influence our weather. Exactly how long we remain active is up for
debate amongst the models at this point. The GFS brings an
offshore ridge near the west coast shifting the majority of the
atmospheric dynamics and moisture to the north ultimately leading
to a drier forecast. The ECMWF with support from the Canadian
model keeps the ridge further offshore and the opportunity for
precipitation alive much later into the week. At this point I have
leaned toward the Euro due to performance up to this point with
winter systems and kept POPs above climo through Wednesday. Along
with precip into the middle of the week, the Euro also brings
another round of cold continental polar air into the region
starting Wednesday sending our temperatures back below normal. In
turn the temperatures were trended down, but not yet to the full
extent of the ECMWF as I want just a bit more confidence. The
polar airmass is also quite dry so once the modified polar front
passes Wednesday, POPs drop off as well. Snow levels with the
precipitation in the extended forecast once again looks to sit
above most valley floors minus the far northern ones leading to
mainly a valley rain/mountain snow event. Higher benches such as
the West Plains, Upper Columbia Basin, etc. could see some snow
mix in overnight as our diurnal swings bottoms out. While this
forecast leaned more towards the Euro, model trends will have to
be closely monitored to better pin down the details as we near
this timeframe. /Fliehman

&&

.AVIATION...
12Z TAFS: A weak frontal boundary will continue to lift to the
northeast this morning potentially impacting all forecast sites.
The threat will exit MWH and EAT by 15z and the other sites
between 17-19z. While vsbys and cigs will generally be in the VFR
category...brief MVFR conditions will be possible but not worth
mentioning in forecast. The most difficult part of the forecast is
what will the precipitation fall as. Based on elevated melting
layer and temperatures near or below freezing at all sites...a
winter mix is expected with the best chances of freezing rain
expected for PUW and MWH. Confidence is low though as this is a
very complex situation. The front will exit the area...with dry
weather for most sites afterwords. Later tonight another round of
precipitation arrives late tonight (after 08z) and this will
mainly impact GEG- SFF- COE. Suspect this round will mainly be
rain...but that is far from certain. fx

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        34  31  38  34  42  29 /  50  30  40 100  60  30
Coeur d`Alene  34  32  40  33  41  31 /  70  40  50 100  70  30
Pullman        39  29  42  35  42  32 /  60  10  20 100  70  30
Lewiston       40  31  45  39  47  35 /  80  10  10  80  50  30
Colville       34  26  38  34  43  26 /  50  40  70 100  40  30
Sandpoint      34  30  39  33  41  29 /  60  70  70 100  70  30
Kellogg        34  31  39  32  39  32 /  90  60  60 100  90  40
Moses Lake     35  21  37  31  47  28 /  60   0  70 100  30  20
Wenatchee      39  28  36  31  45  31 /  70   0  80 100  20  30
Omak           36  27  37  30  43  27 /  50  20  90 100  20  30

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Central Panhandle Mountains-Northern
     Panhandle.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Northeast Mountains-Okanogan Highlands.

     Winter Storm Watch from Friday morning through late Friday night
     for East Slopes Northern Cascades.

&&

$$






000
FXUS66 KOTX 201120
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
320 AM PST THU NOV 20 2014

.SYNOPSIS...
A weak weather system will arrive late tonight into Thursday with
the potential for a light wintry mix of rain...snow...and freezing
rain. A stronger, wetter and windier weather system will arrive
Friday persisting into the weekend with heavy snow amounts
possible over the mountains. The weather pattern will remain
active through the middle of next week.



&&

.DISCUSSION...

...Pockets of freezing rain possible this morning over the lower
Columbia Basin and portions of the Washington Palouse...

Today and tonight ...The ridge of the past week and a half is
becoming a relic of the past as disturbance number one (of many)
is currently passing through western Washington with its sights
set on the Inland Northwest. This disturbance is comprised of an
elongating band of moisture extending from a weak upper level low
just west of Vancouver Island southeast into in southwest Idaho.
Associated with this band of moisture was a weakening warm front
which will provide the focus for the weather today. Models have
remained rather consistent in taking this front from its current
position over south-central Washington northeast across the
remainder of eastern Washington and north Idaho today. The trend
of slowing the front continues...and now it looks like the front
won`t arrive into the northern tip of Idaho until around midday.

Forcing and lifting along the front looks rather weak...and it will
likely continue to diminish as it treks northeastward today.
Nonetheless...with a modified arctic air mass still firmly
entrenched over most of the region...it won`t take much lifting to
generate precipitation as the isentropic surfaces look rather
steep. That suggests most of the region will be subject to
precipitation today...but the question is what will it fall as.
This remains an exceedingly tricky forecast element. Model cross-
sections and 0-4km max wet-bulb temperatures continue to show an
elevated wedge of above freezing air over the extreme southern
portion of our forecast area. This encompasses the area generally
south of a line from Wenatchee to Moses Lake...then Pullman. Any
locations south of this line will be subject to light freezing
rain (with a small chance of sleet)...through this morning.
Meanwhile anything north will generally see snow. Again amounts
will be fairly light. Through the end of the day most locations
will see an tenth of an inch of precipitation or less. Snow
amounts will reflect this light precipitation with locations
generally seeing less than an inch. As for the freezing
rain...amounts will also be light...however any freezing rain can
result in potential travel difficulties. The potential for travel
problems will generally be confined to the morning hours as any
dirunal heating should bring road temperatures above freezing by
midday. Additionally...most of the precipitation threat also move
north and east of this elevated warm layer as well.

The front is expected to dissipate rapidly during the
evening...but that won`t be the end of the precipitation.
Initially upslope flow and residual frontal moisture will keep the
light snow falling over north Idaho...however things will
intensify somewhat overnight. This next round of precipitation
will be delivered care of the shortwave trough off of Vancouver
Island tracking through southern British Columbia overnight. The
lifting associated with this feature will not be strong...however
the atmosphere below 650 mbs or roughly 10k feet will become
saturated overnight. Renewed isentropic ascent...especially for
locations north of Highway 2 (in Washington) and I-90 (in
Idaho)...should result in a second round of precipitation. The
warm layer will surge a little farther north as well. By
morning...a shallow elevated melting layer could move as far north
as a Lake Chelan to Spokane line. This will be on the southern
edge of the next round of precipitation so there`s a small chance
of more freezing rain...however by that time...surface wet-bulb
temperatures are expected to near or exceed freezing...so main
precipitation would be rain or a rain snow mix for the Spokane
area and southeast sections of the Columbia Basin. For locations
over the northwest portion of the Basin...including Grand
Coulee...Wilbur...and Davenport there will be a small chance of
freezing rain. Confidence is not high however...as so much is
dependant on what happens today in terms of surface warming. If a
location gets above freezing today...it will likely remain that
way overnight as well. fx


...MODERATE TO HEAVY MOUNTAIN SNOW POSSIBLE LATE FRIDAY INTO
SATURDAY...

Friday through Monday: A series of systems slide across the
Inland NW, with several opportunities for rain and snow. First
early Friday the next system will be approaching. There will be a
threat of light snow or freezing rain/freezing drizzle across the
Upper Columbia Basin through northeast WA and north ID due to some
isentropic lift and low level moisture. The moisture is deepest
below about 650 to 700 mbs, below the core of the snow growth
zone. So this suggest the potential for a mixture of snow,
freezing rain or freezing drizzle, and rain as the precipitation
type. So we could be looking for some slick conditions along the
I-90/US-2/US-95 corridor in the morning.

Then Friday afternoon into Friday evening deepening isentropic
ascent and moisture noses across the Cascades into eastern WA and
north ID with the warm front. This will lead to increasing
precipitation from west to east, so that by early evening most of
Washington will be enveloped by it and by middle to late evening
much of Idaho will be too. Overnight the associated cold front
slips east of the Cascades, leading to dwindling precipitation in
the lee of the Cascades and western Columbia Basin. By late
Saturday morning to afternoon the highest threat briefly retreats
to the mountains, with winds becoming breezy to locally windy.
With the evolution discussed, the next questions surround snow
levels and precipitation amounts.

* Snow levels: The location of the snow hasn`t changed much from
  previous thinking. Based on wet-bulb zero heights, snow levels
  from Friday afternoon through Friday night will be around
  3000-4000 feet across the Cascades and northern mountains and
  4000 to 5000 feet southeast. However colder air trapped near the
  Cascades in the low level southeast flow will keep snow levels
  1500-3000 feet. This includes places in the lee of the Cascades,
  including the Okanogan Valley and Highlands through the
  Waterville Plateau and Wenatchee area. So the Cascades and areas
  the remaining mountain areas above 3000 to 4000 feet (except for
  the Blue Mountains where snow levels look too high to have much
  impact in the populated areas). Winter storm watches
  remain place for the Cascades and in the north WA and ID
  mountains above 4000 feet. We will monitor the potential need
  for advisories outside of the mountains, in the hills around the
  Okanogan Valley and Waterville Plateau and Wenatchee area.
  However accumulations may be limited if milder air is able to
  move in or precipitation amounts are not as high as expected.
  Behind the cold front going into Saturday afternoon snow levels
  drop to between 2500-3000 feet. So this means any lingering
  showers may be a mix of rain and snow, including as far south as
  the I-90 corridor. However by then the better precipitation
  threat starts that shift into the mountains.

* Precipitation amounts: Regional PWATs rise to between 0.45 to
  0.75 inches (or 130 to 200% of normal). So this is a juicy
  system and all models generate decent precipitation amounts. In
  the 24-hour period between Friday afternoon and Saturday
  afternoon models generate between 0.30 to 0.60 inches of liquid
  precipitation across a good portion of the Inland NW, with lower
  amounts over the deeper Columbia Basin and higher amounts
  between 0.75 to 1.0 inch in the mountains. For areas the
  mountain snow this could translate to between 6 to 12 inches,
  while the lower elevations closer to the Cascades could see
  anywhere from a trace to a couple inches or so. These numbers,
  especially the lower elevation ones, will continue to be fine-
  tuned.

From Saturday evening into Sunday morning a secondary disturbance
slips by, renewing the precipitation threat outside of the
mountains. However precipitation amount as compared to Friday
night, look light. A third and more organized system comes in
sometime between Sunday and Monday morning. This taps some
subtropical moisture, but it is not as robust as the Friday night
system. Still models generate a modest precipitation threat across
all but the lee of the Cascades and deeper Basin. When and where
this develops is where model disagreement lingers. Most models
start precipitation early Sunday near Cascades. Yet farther east
some start it up through southeast WA and the central Panhandle in
the morning and others hold it off until afternoon. Chances remain
high outside of the lee of the Cascades and deeper Columbia Basin
through the evening, then dissipate overnight into Monday. Still
the leading edge of a fourth system, a warm front, approaches from
the west Monday afternoon. Whether moisture is deep enough to
allow precipitation to redevelop or just thickening clouds is even
less agreed upon. Chances will remain high near the Cascades and
lower elsewhere. As for snow levels through the period from
Saturday night through Monday, they waver between about 1500 and
3000 feet during the night and early morning hours and 2000 and
4000 feet during the day and early evening hours. The lowest of
those lay toward the northeast WA and north ID. This translates to
the potential for snow down to valley floors, especially at night,
and perhaps some light accumulations in the valleys. This includes
potentially the I-90 corridor, especially east of Ritzville and
the higher Palouse, as well as areas from the Waterville Plateau
north. /J. Cote`

Monday Night through Thursday: Pattern looks to remain active
early in the week as the moist northwesterly flow continues to
influence our weather. Exactly how long we remain active is up for
debate amongst the models at this point. The GFS brings an
offshore ridge near the west coast shifting the majority of the
atmospheric dynamics and moisture to the north ultimately leading
to a drier forecast. The ECMWF with support from the Canadian
model keeps the ridge further offshore and the opportunity for
precipitation alive much later into the week. At this point I have
leaned toward the Euro due to performance up to this point with
winter systems and kept POPs above climo through Wednesday. Along
with precip into the middle of the week, the Euro also brings
another round of cold continental polar air into the region
starting Wednesday sending our temperatures back below normal. In
turn the temperatures were trended down, but not yet to the full
extent of the ECMWF as I want just a bit more confidence. The
polar airmass is also quite dry so once the modified polar front
passes Wednesday, POPs drop off as well. Snow levels with the
precipitation in the extended forecast once again looks to sit
above most valley floors minus the far northern ones leading to
mainly a valley rain/mountain snow event. Higher benches such as
the West Plains, Upper Columbia Basin, etc. could see some snow
mix in overnight as our diurnal swings bottoms out. While this
forecast leaned more towards the Euro, model trends will have to
be closely monitored to better pin down the details as we near
this timeframe. /Fliehman

&&

.AVIATION...
06Z TAFS: A weak frontal boundary lifts into the region between
09-13Z spreading a wintry mix of light snow, sleet, and some
freezing rain. Accumulations, if any, are expected to be very
light. After the front moves off Thursday morning...a moist
boundary layer with weak upslope flow will maintain the threat of
MVFR ceilings over the eastern TAF sites. /sb

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        34  31  38  34  42  29 /  50  30  40 100  60  30
Coeur d`Alene  34  32  40  33  41  31 /  70  40  50 100  70  30
Pullman        39  29  42  35  42  32 /  60  10  20 100  70  30
Lewiston       40  31  45  39  47  35 /  80  10  10  80  50  30
Colville       34  26  38  34  43  26 /  50  40  70 100  40  30
Sandpoint      34  30  39  33  41  29 /  60  70  70 100  70  30
Kellogg        34  31  39  32  39  32 /  90  60  60 100  90  40
Moses Lake     35  21  37  31  47  28 /  60   0  70 100  30  20
Wenatchee      39  28  36  31  45  31 /  70   0  80 100  20  30
Omak           36  27  37  30  43  27 /  50  20  90 100  20  30

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Central Panhandle Mountains-Northern
     Panhandle.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Northeast Mountains-Okanogan Highlands.

     Winter Storm Watch from Friday morning through late Friday night
     for East Slopes Northern Cascades.

&&

$$






000
FXUS66 KOTX 201120
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
320 AM PST THU NOV 20 2014

.SYNOPSIS...
A weak weather system will arrive late tonight into Thursday with
the potential for a light wintry mix of rain...snow...and freezing
rain. A stronger, wetter and windier weather system will arrive
Friday persisting into the weekend with heavy snow amounts
possible over the mountains. The weather pattern will remain
active through the middle of next week.



&&

.DISCUSSION...

...Pockets of freezing rain possible this morning over the lower
Columbia Basin and portions of the Washington Palouse...

Today and tonight ...The ridge of the past week and a half is
becoming a relic of the past as disturbance number one (of many)
is currently passing through western Washington with its sights
set on the Inland Northwest. This disturbance is comprised of an
elongating band of moisture extending from a weak upper level low
just west of Vancouver Island southeast into in southwest Idaho.
Associated with this band of moisture was a weakening warm front
which will provide the focus for the weather today. Models have
remained rather consistent in taking this front from its current
position over south-central Washington northeast across the
remainder of eastern Washington and north Idaho today. The trend
of slowing the front continues...and now it looks like the front
won`t arrive into the northern tip of Idaho until around midday.

Forcing and lifting along the front looks rather weak...and it will
likely continue to diminish as it treks northeastward today.
Nonetheless...with a modified arctic air mass still firmly
entrenched over most of the region...it won`t take much lifting to
generate precipitation as the isentropic surfaces look rather
steep. That suggests most of the region will be subject to
precipitation today...but the question is what will it fall as.
This remains an exceedingly tricky forecast element. Model cross-
sections and 0-4km max wet-bulb temperatures continue to show an
elevated wedge of above freezing air over the extreme southern
portion of our forecast area. This encompasses the area generally
south of a line from Wenatchee to Moses Lake...then Pullman. Any
locations south of this line will be subject to light freezing
rain (with a small chance of sleet)...through this morning.
Meanwhile anything north will generally see snow. Again amounts
will be fairly light. Through the end of the day most locations
will see an tenth of an inch of precipitation or less. Snow
amounts will reflect this light precipitation with locations
generally seeing less than an inch. As for the freezing
rain...amounts will also be light...however any freezing rain can
result in potential travel difficulties. The potential for travel
problems will generally be confined to the morning hours as any
dirunal heating should bring road temperatures above freezing by
midday. Additionally...most of the precipitation threat also move
north and east of this elevated warm layer as well.

The front is expected to dissipate rapidly during the
evening...but that won`t be the end of the precipitation.
Initially upslope flow and residual frontal moisture will keep the
light snow falling over north Idaho...however things will
intensify somewhat overnight. This next round of precipitation
will be delivered care of the shortwave trough off of Vancouver
Island tracking through southern British Columbia overnight. The
lifting associated with this feature will not be strong...however
the atmosphere below 650 mbs or roughly 10k feet will become
saturated overnight. Renewed isentropic ascent...especially for
locations north of Highway 2 (in Washington) and I-90 (in
Idaho)...should result in a second round of precipitation. The
warm layer will surge a little farther north as well. By
morning...a shallow elevated melting layer could move as far north
as a Lake Chelan to Spokane line. This will be on the southern
edge of the next round of precipitation so there`s a small chance
of more freezing rain...however by that time...surface wet-bulb
temperatures are expected to near or exceed freezing...so main
precipitation would be rain or a rain snow mix for the Spokane
area and southeast sections of the Columbia Basin. For locations
over the northwest portion of the Basin...including Grand
Coulee...Wilbur...and Davenport there will be a small chance of
freezing rain. Confidence is not high however...as so much is
dependant on what happens today in terms of surface warming. If a
location gets above freezing today...it will likely remain that
way overnight as well. fx


...MODERATE TO HEAVY MOUNTAIN SNOW POSSIBLE LATE FRIDAY INTO
SATURDAY...

Friday through Monday: A series of systems slide across the
Inland NW, with several opportunities for rain and snow. First
early Friday the next system will be approaching. There will be a
threat of light snow or freezing rain/freezing drizzle across the
Upper Columbia Basin through northeast WA and north ID due to some
isentropic lift and low level moisture. The moisture is deepest
below about 650 to 700 mbs, below the core of the snow growth
zone. So this suggest the potential for a mixture of snow,
freezing rain or freezing drizzle, and rain as the precipitation
type. So we could be looking for some slick conditions along the
I-90/US-2/US-95 corridor in the morning.

Then Friday afternoon into Friday evening deepening isentropic
ascent and moisture noses across the Cascades into eastern WA and
north ID with the warm front. This will lead to increasing
precipitation from west to east, so that by early evening most of
Washington will be enveloped by it and by middle to late evening
much of Idaho will be too. Overnight the associated cold front
slips east of the Cascades, leading to dwindling precipitation in
the lee of the Cascades and western Columbia Basin. By late
Saturday morning to afternoon the highest threat briefly retreats
to the mountains, with winds becoming breezy to locally windy.
With the evolution discussed, the next questions surround snow
levels and precipitation amounts.

* Snow levels: The location of the snow hasn`t changed much from
  previous thinking. Based on wet-bulb zero heights, snow levels
  from Friday afternoon through Friday night will be around
  3000-4000 feet across the Cascades and northern mountains and
  4000 to 5000 feet southeast. However colder air trapped near the
  Cascades in the low level southeast flow will keep snow levels
  1500-3000 feet. This includes places in the lee of the Cascades,
  including the Okanogan Valley and Highlands through the
  Waterville Plateau and Wenatchee area. So the Cascades and areas
  the remaining mountain areas above 3000 to 4000 feet (except for
  the Blue Mountains where snow levels look too high to have much
  impact in the populated areas). Winter storm watches
  remain place for the Cascades and in the north WA and ID
  mountains above 4000 feet. We will monitor the potential need
  for advisories outside of the mountains, in the hills around the
  Okanogan Valley and Waterville Plateau and Wenatchee area.
  However accumulations may be limited if milder air is able to
  move in or precipitation amounts are not as high as expected.
  Behind the cold front going into Saturday afternoon snow levels
  drop to between 2500-3000 feet. So this means any lingering
  showers may be a mix of rain and snow, including as far south as
  the I-90 corridor. However by then the better precipitation
  threat starts that shift into the mountains.

* Precipitation amounts: Regional PWATs rise to between 0.45 to
  0.75 inches (or 130 to 200% of normal). So this is a juicy
  system and all models generate decent precipitation amounts. In
  the 24-hour period between Friday afternoon and Saturday
  afternoon models generate between 0.30 to 0.60 inches of liquid
  precipitation across a good portion of the Inland NW, with lower
  amounts over the deeper Columbia Basin and higher amounts
  between 0.75 to 1.0 inch in the mountains. For areas the
  mountain snow this could translate to between 6 to 12 inches,
  while the lower elevations closer to the Cascades could see
  anywhere from a trace to a couple inches or so. These numbers,
  especially the lower elevation ones, will continue to be fine-
  tuned.

From Saturday evening into Sunday morning a secondary disturbance
slips by, renewing the precipitation threat outside of the
mountains. However precipitation amount as compared to Friday
night, look light. A third and more organized system comes in
sometime between Sunday and Monday morning. This taps some
subtropical moisture, but it is not as robust as the Friday night
system. Still models generate a modest precipitation threat across
all but the lee of the Cascades and deeper Basin. When and where
this develops is where model disagreement lingers. Most models
start precipitation early Sunday near Cascades. Yet farther east
some start it up through southeast WA and the central Panhandle in
the morning and others hold it off until afternoon. Chances remain
high outside of the lee of the Cascades and deeper Columbia Basin
through the evening, then dissipate overnight into Monday. Still
the leading edge of a fourth system, a warm front, approaches from
the west Monday afternoon. Whether moisture is deep enough to
allow precipitation to redevelop or just thickening clouds is even
less agreed upon. Chances will remain high near the Cascades and
lower elsewhere. As for snow levels through the period from
Saturday night through Monday, they waver between about 1500 and
3000 feet during the night and early morning hours and 2000 and
4000 feet during the day and early evening hours. The lowest of
those lay toward the northeast WA and north ID. This translates to
the potential for snow down to valley floors, especially at night,
and perhaps some light accumulations in the valleys. This includes
potentially the I-90 corridor, especially east of Ritzville and
the higher Palouse, as well as areas from the Waterville Plateau
north. /J. Cote`

Monday Night through Thursday: Pattern looks to remain active
early in the week as the moist northwesterly flow continues to
influence our weather. Exactly how long we remain active is up for
debate amongst the models at this point. The GFS brings an
offshore ridge near the west coast shifting the majority of the
atmospheric dynamics and moisture to the north ultimately leading
to a drier forecast. The ECMWF with support from the Canadian
model keeps the ridge further offshore and the opportunity for
precipitation alive much later into the week. At this point I have
leaned toward the Euro due to performance up to this point with
winter systems and kept POPs above climo through Wednesday. Along
with precip into the middle of the week, the Euro also brings
another round of cold continental polar air into the region
starting Wednesday sending our temperatures back below normal. In
turn the temperatures were trended down, but not yet to the full
extent of the ECMWF as I want just a bit more confidence. The
polar airmass is also quite dry so once the modified polar front
passes Wednesday, POPs drop off as well. Snow levels with the
precipitation in the extended forecast once again looks to sit
above most valley floors minus the far northern ones leading to
mainly a valley rain/mountain snow event. Higher benches such as
the West Plains, Upper Columbia Basin, etc. could see some snow
mix in overnight as our diurnal swings bottoms out. While this
forecast leaned more towards the Euro, model trends will have to
be closely monitored to better pin down the details as we near
this timeframe. /Fliehman

&&

.AVIATION...
06Z TAFS: A weak frontal boundary lifts into the region between
09-13Z spreading a wintry mix of light snow, sleet, and some
freezing rain. Accumulations, if any, are expected to be very
light. After the front moves off Thursday morning...a moist
boundary layer with weak upslope flow will maintain the threat of
MVFR ceilings over the eastern TAF sites. /sb

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        34  31  38  34  42  29 /  50  30  40 100  60  30
Coeur d`Alene  34  32  40  33  41  31 /  70  40  50 100  70  30
Pullman        39  29  42  35  42  32 /  60  10  20 100  70  30
Lewiston       40  31  45  39  47  35 /  80  10  10  80  50  30
Colville       34  26  38  34  43  26 /  50  40  70 100  40  30
Sandpoint      34  30  39  33  41  29 /  60  70  70 100  70  30
Kellogg        34  31  39  32  39  32 /  90  60  60 100  90  40
Moses Lake     35  21  37  31  47  28 /  60   0  70 100  30  20
Wenatchee      39  28  36  31  45  31 /  70   0  80 100  20  30
Omak           36  27  37  30  43  27 /  50  20  90 100  20  30

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Central Panhandle Mountains-Northern
     Panhandle.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Northeast Mountains-Okanogan Highlands.

     Winter Storm Watch from Friday morning through late Friday night
     for East Slopes Northern Cascades.

&&

$$





000
FXUS66 KOTX 201120
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
320 AM PST THU NOV 20 2014

.SYNOPSIS...
A weak weather system will arrive late tonight into Thursday with
the potential for a light wintry mix of rain...snow...and freezing
rain. A stronger, wetter and windier weather system will arrive
Friday persisting into the weekend with heavy snow amounts
possible over the mountains. The weather pattern will remain
active through the middle of next week.



&&

.DISCUSSION...

...Pockets of freezing rain possible this morning over the lower
Columbia Basin and portions of the Washington Palouse...

Today and tonight ...The ridge of the past week and a half is
becoming a relic of the past as disturbance number one (of many)
is currently passing through western Washington with its sights
set on the Inland Northwest. This disturbance is comprised of an
elongating band of moisture extending from a weak upper level low
just west of Vancouver Island southeast into in southwest Idaho.
Associated with this band of moisture was a weakening warm front
which will provide the focus for the weather today. Models have
remained rather consistent in taking this front from its current
position over south-central Washington northeast across the
remainder of eastern Washington and north Idaho today. The trend
of slowing the front continues...and now it looks like the front
won`t arrive into the northern tip of Idaho until around midday.

Forcing and lifting along the front looks rather weak...and it will
likely continue to diminish as it treks northeastward today.
Nonetheless...with a modified arctic air mass still firmly
entrenched over most of the region...it won`t take much lifting to
generate precipitation as the isentropic surfaces look rather
steep. That suggests most of the region will be subject to
precipitation today...but the question is what will it fall as.
This remains an exceedingly tricky forecast element. Model cross-
sections and 0-4km max wet-bulb temperatures continue to show an
elevated wedge of above freezing air over the extreme southern
portion of our forecast area. This encompasses the area generally
south of a line from Wenatchee to Moses Lake...then Pullman. Any
locations south of this line will be subject to light freezing
rain (with a small chance of sleet)...through this morning.
Meanwhile anything north will generally see snow. Again amounts
will be fairly light. Through the end of the day most locations
will see an tenth of an inch of precipitation or less. Snow
amounts will reflect this light precipitation with locations
generally seeing less than an inch. As for the freezing
rain...amounts will also be light...however any freezing rain can
result in potential travel difficulties. The potential for travel
problems will generally be confined to the morning hours as any
dirunal heating should bring road temperatures above freezing by
midday. Additionally...most of the precipitation threat also move
north and east of this elevated warm layer as well.

The front is expected to dissipate rapidly during the
evening...but that won`t be the end of the precipitation.
Initially upslope flow and residual frontal moisture will keep the
light snow falling over north Idaho...however things will
intensify somewhat overnight. This next round of precipitation
will be delivered care of the shortwave trough off of Vancouver
Island tracking through southern British Columbia overnight. The
lifting associated with this feature will not be strong...however
the atmosphere below 650 mbs or roughly 10k feet will become
saturated overnight. Renewed isentropic ascent...especially for
locations north of Highway 2 (in Washington) and I-90 (in
Idaho)...should result in a second round of precipitation. The
warm layer will surge a little farther north as well. By
morning...a shallow elevated melting layer could move as far north
as a Lake Chelan to Spokane line. This will be on the southern
edge of the next round of precipitation so there`s a small chance
of more freezing rain...however by that time...surface wet-bulb
temperatures are expected to near or exceed freezing...so main
precipitation would be rain or a rain snow mix for the Spokane
area and southeast sections of the Columbia Basin. For locations
over the northwest portion of the Basin...including Grand
Coulee...Wilbur...and Davenport there will be a small chance of
freezing rain. Confidence is not high however...as so much is
dependant on what happens today in terms of surface warming. If a
location gets above freezing today...it will likely remain that
way overnight as well. fx


...MODERATE TO HEAVY MOUNTAIN SNOW POSSIBLE LATE FRIDAY INTO
SATURDAY...

Friday through Monday: A series of systems slide across the
Inland NW, with several opportunities for rain and snow. First
early Friday the next system will be approaching. There will be a
threat of light snow or freezing rain/freezing drizzle across the
Upper Columbia Basin through northeast WA and north ID due to some
isentropic lift and low level moisture. The moisture is deepest
below about 650 to 700 mbs, below the core of the snow growth
zone. So this suggest the potential for a mixture of snow,
freezing rain or freezing drizzle, and rain as the precipitation
type. So we could be looking for some slick conditions along the
I-90/US-2/US-95 corridor in the morning.

Then Friday afternoon into Friday evening deepening isentropic
ascent and moisture noses across the Cascades into eastern WA and
north ID with the warm front. This will lead to increasing
precipitation from west to east, so that by early evening most of
Washington will be enveloped by it and by middle to late evening
much of Idaho will be too. Overnight the associated cold front
slips east of the Cascades, leading to dwindling precipitation in
the lee of the Cascades and western Columbia Basin. By late
Saturday morning to afternoon the highest threat briefly retreats
to the mountains, with winds becoming breezy to locally windy.
With the evolution discussed, the next questions surround snow
levels and precipitation amounts.

* Snow levels: The location of the snow hasn`t changed much from
  previous thinking. Based on wet-bulb zero heights, snow levels
  from Friday afternoon through Friday night will be around
  3000-4000 feet across the Cascades and northern mountains and
  4000 to 5000 feet southeast. However colder air trapped near the
  Cascades in the low level southeast flow will keep snow levels
  1500-3000 feet. This includes places in the lee of the Cascades,
  including the Okanogan Valley and Highlands through the
  Waterville Plateau and Wenatchee area. So the Cascades and areas
  the remaining mountain areas above 3000 to 4000 feet (except for
  the Blue Mountains where snow levels look too high to have much
  impact in the populated areas). Winter storm watches
  remain place for the Cascades and in the north WA and ID
  mountains above 4000 feet. We will monitor the potential need
  for advisories outside of the mountains, in the hills around the
  Okanogan Valley and Waterville Plateau and Wenatchee area.
  However accumulations may be limited if milder air is able to
  move in or precipitation amounts are not as high as expected.
  Behind the cold front going into Saturday afternoon snow levels
  drop to between 2500-3000 feet. So this means any lingering
  showers may be a mix of rain and snow, including as far south as
  the I-90 corridor. However by then the better precipitation
  threat starts that shift into the mountains.

* Precipitation amounts: Regional PWATs rise to between 0.45 to
  0.75 inches (or 130 to 200% of normal). So this is a juicy
  system and all models generate decent precipitation amounts. In
  the 24-hour period between Friday afternoon and Saturday
  afternoon models generate between 0.30 to 0.60 inches of liquid
  precipitation across a good portion of the Inland NW, with lower
  amounts over the deeper Columbia Basin and higher amounts
  between 0.75 to 1.0 inch in the mountains. For areas the
  mountain snow this could translate to between 6 to 12 inches,
  while the lower elevations closer to the Cascades could see
  anywhere from a trace to a couple inches or so. These numbers,
  especially the lower elevation ones, will continue to be fine-
  tuned.

From Saturday evening into Sunday morning a secondary disturbance
slips by, renewing the precipitation threat outside of the
mountains. However precipitation amount as compared to Friday
night, look light. A third and more organized system comes in
sometime between Sunday and Monday morning. This taps some
subtropical moisture, but it is not as robust as the Friday night
system. Still models generate a modest precipitation threat across
all but the lee of the Cascades and deeper Basin. When and where
this develops is where model disagreement lingers. Most models
start precipitation early Sunday near Cascades. Yet farther east
some start it up through southeast WA and the central Panhandle in
the morning and others hold it off until afternoon. Chances remain
high outside of the lee of the Cascades and deeper Columbia Basin
through the evening, then dissipate overnight into Monday. Still
the leading edge of a fourth system, a warm front, approaches from
the west Monday afternoon. Whether moisture is deep enough to
allow precipitation to redevelop or just thickening clouds is even
less agreed upon. Chances will remain high near the Cascades and
lower elsewhere. As for snow levels through the period from
Saturday night through Monday, they waver between about 1500 and
3000 feet during the night and early morning hours and 2000 and
4000 feet during the day and early evening hours. The lowest of
those lay toward the northeast WA and north ID. This translates to
the potential for snow down to valley floors, especially at night,
and perhaps some light accumulations in the valleys. This includes
potentially the I-90 corridor, especially east of Ritzville and
the higher Palouse, as well as areas from the Waterville Plateau
north. /J. Cote`

Monday Night through Thursday: Pattern looks to remain active
early in the week as the moist northwesterly flow continues to
influence our weather. Exactly how long we remain active is up for
debate amongst the models at this point. The GFS brings an
offshore ridge near the west coast shifting the majority of the
atmospheric dynamics and moisture to the north ultimately leading
to a drier forecast. The ECMWF with support from the Canadian
model keeps the ridge further offshore and the opportunity for
precipitation alive much later into the week. At this point I have
leaned toward the Euro due to performance up to this point with
winter systems and kept POPs above climo through Wednesday. Along
with precip into the middle of the week, the Euro also brings
another round of cold continental polar air into the region
starting Wednesday sending our temperatures back below normal. In
turn the temperatures were trended down, but not yet to the full
extent of the ECMWF as I want just a bit more confidence. The
polar airmass is also quite dry so once the modified polar front
passes Wednesday, POPs drop off as well. Snow levels with the
precipitation in the extended forecast once again looks to sit
above most valley floors minus the far northern ones leading to
mainly a valley rain/mountain snow event. Higher benches such as
the West Plains, Upper Columbia Basin, etc. could see some snow
mix in overnight as our diurnal swings bottoms out. While this
forecast leaned more towards the Euro, model trends will have to
be closely monitored to better pin down the details as we near
this timeframe. /Fliehman

&&

.AVIATION...
06Z TAFS: A weak frontal boundary lifts into the region between
09-13Z spreading a wintry mix of light snow, sleet, and some
freezing rain. Accumulations, if any, are expected to be very
light. After the front moves off Thursday morning...a moist
boundary layer with weak upslope flow will maintain the threat of
MVFR ceilings over the eastern TAF sites. /sb

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        34  31  38  34  42  29 /  50  30  40 100  60  30
Coeur d`Alene  34  32  40  33  41  31 /  70  40  50 100  70  30
Pullman        39  29  42  35  42  32 /  60  10  20 100  70  30
Lewiston       40  31  45  39  47  35 /  80  10  10  80  50  30
Colville       34  26  38  34  43  26 /  50  40  70 100  40  30
Sandpoint      34  30  39  33  41  29 /  60  70  70 100  70  30
Kellogg        34  31  39  32  39  32 /  90  60  60 100  90  40
Moses Lake     35  21  37  31  47  28 /  60   0  70 100  30  20
Wenatchee      39  28  36  31  45  31 /  70   0  80 100  20  30
Omak           36  27  37  30  43  27 /  50  20  90 100  20  30

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Central Panhandle Mountains-Northern
     Panhandle.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Northeast Mountains-Okanogan Highlands.

     Winter Storm Watch from Friday morning through late Friday night
     for East Slopes Northern Cascades.

&&

$$





000
FXUS66 KOTX 200614
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1013 PM PST WED NOV 19 2014

.SYNOPSIS...
A weak weather system will arrive late tonight into Thursday with
the potential for a light wintry mix of rain...snow...and freezing
rain. A stronger, wetter and windier weather system will arrive
Friday persisting into the weekend with heavy snow amounts
possible over the mountains. The weather pattern will remain
active through the middle of next week.


&&

.DISCUSSION...

...SLICK TRAVEL EXPECTED OVER SOUTHEASTERN WA ALONG HIGHWAY 26 and
HIGHWAY 12 DUE TO FREEZING RAIN AND SLEET EARLY THURSDAY MORNING...

...A MIX OF LIGHT SNOW AND SLEET POSSIBLE DURING THE MORNING
COMMUTE IN EASTERN WA AND NORTHERN IDAHO...

Evening update: A tricky yet low precipitation event will pass
through the region early Thursday morning and depart in the
afternoon. At this time, it looks like the best chance for
freezing rain mixing with sleet will be over southeastern WA from
northern Garfield County into southwestern Whitman...and southern
Adams County. These areas are currently in the mid 20s and model
profiles are most favorable for a these precipitation types.
Amounts are the unknown factor with the last few runs of the HRRR
simulated reflectivity trending toward the drier NAM. This will
mean the potential ranging from a trace to few hundreths of
liquid. Slick conditions a strong possibility for the Thursday
morning commute but anticipated ice accumulations remains in low
confidence. Nonetheless, Highway 26 and Highway 12 look to carry
the highest threat for icy roads from freezing rain/sleet.

The further north you travel from Pullman to Spokane-CDA-Kellogg-
St Maries. The chance for precipitation to remain as snow becomes
much better. My guess is areas of Benewah/Latah/Kootenai/Shoshone
County will stand the best chance for up to an inch of snow with
less than a half an inch into Spokane, NE WA, and far northern ID
Panhandle. One reason is the lack of QPF but a second will be low
snow ratios. KOTX sounding indicated the top of the inversion
layer around +3C. While this will wetbulb below freezing to
support snow, snowflakes will undergo some melting/rounding and
just having a hard time supporting snow ratios above 10:1. If
precipitation intensity is higher than expected, this could yield
slightly higher amounts. Another factor is temperatures are
currently above freezing between Pullman and Lewiston. Local
downsloping this afternoon warmed temperatures into the 40`s.
Dewpoints remain dry enough to support wetbulbing near to below
freezing but not by much and if precip intensity remains light,
this may never occur. On the other end of the spectrum, it is
still only 9PM and precipitation will not arrive until 5AM so
there is still time to cool but increasing clouds does not favor
any big drops.

Further west, a passing trace to hundreth is expected as the
frontal occlusion lifts north. Models do not show much in the way
of QPF from Wenatchee to Omak but dynamics are a bit stronger on
this side of the CWA so will leave some chance for snow with
amounts generally between a trace and tenth. Up to an inch will be
possible in the mountains and across the Cascade Passes.

&&

.AVIATION...
06Z TAFS: A weak frontal boundary lifts into the region between
09-13Z spreading a wintry mix of light snow, sleet, and some
freezing rain. Accumulations, if any, are expected to be very
light. After the front moves off Thursday morning...a moist
boundary layer with weak upslope flow will maintain the threat of
MVFR ceilings over the eastern TAF sites. /sb



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        23  34  31  38  34  42 /  10  70  20  40  90  40
Coeur d`Alene  23  34  32  40  34  41 /  10  70  30  50  90  70
Pullman        31  39  29  42  35  42 /  20  80  20  20  90  70
Lewiston       33  40  31  44  40  47 /  30  80  10  10  80  50
Colville       22  34  26  38  36  42 /   0  30  30  70 100  40
Sandpoint      21  34  30  40  34  41 /   0  50  50  70 100  60
Kellogg        25  34  31  38  34  38 /  10  80  40  50  90  90
Moses Lake     24  35  21  37  31  48 /  40  20  10  70 100  20
Wenatchee      29  39  28  35  33  46 /  50  20  10  80 100  20
Omak           24  36  27  36  31  43 /  10  20  10  80 100  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Central Panhandle Mountains-Northern
     Panhandle.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Northeast Mountains-Okanogan Highlands.

     Winter Storm Watch from Friday morning through late Friday night
     for East Slopes Northern Cascades.

&&

$$





000
FXUS66 KOTX 200614
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1013 PM PST WED NOV 19 2014

.SYNOPSIS...
A weak weather system will arrive late tonight into Thursday with
the potential for a light wintry mix of rain...snow...and freezing
rain. A stronger, wetter and windier weather system will arrive
Friday persisting into the weekend with heavy snow amounts
possible over the mountains. The weather pattern will remain
active through the middle of next week.


&&

.DISCUSSION...

...SLICK TRAVEL EXPECTED OVER SOUTHEASTERN WA ALONG HIGHWAY 26 and
HIGHWAY 12 DUE TO FREEZING RAIN AND SLEET EARLY THURSDAY MORNING...

...A MIX OF LIGHT SNOW AND SLEET POSSIBLE DURING THE MORNING
COMMUTE IN EASTERN WA AND NORTHERN IDAHO...

Evening update: A tricky yet low precipitation event will pass
through the region early Thursday morning and depart in the
afternoon. At this time, it looks like the best chance for
freezing rain mixing with sleet will be over southeastern WA from
northern Garfield County into southwestern Whitman...and southern
Adams County. These areas are currently in the mid 20s and model
profiles are most favorable for a these precipitation types.
Amounts are the unknown factor with the last few runs of the HRRR
simulated reflectivity trending toward the drier NAM. This will
mean the potential ranging from a trace to few hundreths of
liquid. Slick conditions a strong possibility for the Thursday
morning commute but anticipated ice accumulations remains in low
confidence. Nonetheless, Highway 26 and Highway 12 look to carry
the highest threat for icy roads from freezing rain/sleet.

The further north you travel from Pullman to Spokane-CDA-Kellogg-
St Maries. The chance for precipitation to remain as snow becomes
much better. My guess is areas of Benewah/Latah/Kootenai/Shoshone
County will stand the best chance for up to an inch of snow with
less than a half an inch into Spokane, NE WA, and far northern ID
Panhandle. One reason is the lack of QPF but a second will be low
snow ratios. KOTX sounding indicated the top of the inversion
layer around +3C. While this will wetbulb below freezing to
support snow, snowflakes will undergo some melting/rounding and
just having a hard time supporting snow ratios above 10:1. If
precipitation intensity is higher than expected, this could yield
slightly higher amounts. Another factor is temperatures are
currently above freezing between Pullman and Lewiston. Local
downsloping this afternoon warmed temperatures into the 40`s.
Dewpoints remain dry enough to support wetbulbing near to below
freezing but not by much and if precip intensity remains light,
this may never occur. On the other end of the spectrum, it is
still only 9PM and precipitation will not arrive until 5AM so
there is still time to cool but increasing clouds does not favor
any big drops.

Further west, a passing trace to hundreth is expected as the
frontal occlusion lifts north. Models do not show much in the way
of QPF from Wenatchee to Omak but dynamics are a bit stronger on
this side of the CWA so will leave some chance for snow with
amounts generally between a trace and tenth. Up to an inch will be
possible in the mountains and across the Cascade Passes.

&&

.AVIATION...
06Z TAFS: A weak frontal boundary lifts into the region between
09-13Z spreading a wintry mix of light snow, sleet, and some
freezing rain. Accumulations, if any, are expected to be very
light. After the front moves off Thursday morning...a moist
boundary layer with weak upslope flow will maintain the threat of
MVFR ceilings over the eastern TAF sites. /sb



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        23  34  31  38  34  42 /  10  70  20  40  90  40
Coeur d`Alene  23  34  32  40  34  41 /  10  70  30  50  90  70
Pullman        31  39  29  42  35  42 /  20  80  20  20  90  70
Lewiston       33  40  31  44  40  47 /  30  80  10  10  80  50
Colville       22  34  26  38  36  42 /   0  30  30  70 100  40
Sandpoint      21  34  30  40  34  41 /   0  50  50  70 100  60
Kellogg        25  34  31  38  34  38 /  10  80  40  50  90  90
Moses Lake     24  35  21  37  31  48 /  40  20  10  70 100  20
Wenatchee      29  39  28  35  33  46 /  50  20  10  80 100  20
Omak           24  36  27  36  31  43 /  10  20  10  80 100  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Central Panhandle Mountains-Northern
     Panhandle.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Northeast Mountains-Okanogan Highlands.

     Winter Storm Watch from Friday morning through late Friday night
     for East Slopes Northern Cascades.

&&

$$






000
FXUS66 KOTX 200503
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
903 PM PST WED NOV 19 2014

.SYNOPSIS...
A weak weather system will arrive late tonight into Thursday with
the potential for a light wintry mix of rain...snow...and freezing
rain. A stronger, wetter and windier weather system will arrive
Friday persisting into the weekend with heavy snow amounts
possible over the mountains. The weather pattern will remain
active through the middle of next week.


&&

.DISCUSSION...

...SLICK TRAVEL EXPECTED OVER SOUTHEASTERN WA ALONG HIGHWAY 26 and
HIGHWAY 12 DUE TO FREEZING RAIN AND SLEET EARLY THURSDAY MORNING...

...A MIX OF LIGHT SNOW AND SLEET POSSIBLE DURING THE MORNING
COMMUTE IN EASTERN WA AND NORTHERN IDAHO...

Evening update: A tricky yet low precipitation event will pass
through the region early Thursday morning and depart in the
afternoon. At this time, it looks like the best chance for
freezing rain mixing with sleet will be over southeastern WA from
northern Garfield County into southwestern Whitman...and southern
Adams County. These areas are currently in the mid 20s and model
profiles are most favorable for a these precipitation types.
Amounts are the unknown factor with the last few runs of the HRRR
simulated reflectivity trending toward the drier NAM. This will
mean the potential ranging from a trace to few hundreths of
liquid. Slick conditions a strong possibility for the Thursday
morning commute but anticipated ice accumulations remains in low
confidence. Nonetheless, Highway 26 and Highway 12 look to carry
the highest threat for icy roads from freezing rain/sleet.

The further north you travel from Pullman to Spokane-CDA-Kellogg-
St Maries. The chance for precipitation to remain as snow becomes
much better. My guess is areas of Benewah/Latah/Kootenai/Shoshone
County will stand the best chance for up to an inch of snow with
less than a half an inch into Spokane, NE WA, and far northern ID
Panhandle. One reason is the lack of QPF but a second will be low
snow ratios. KOTX sounding indicated the top of the inversion
layer around +3C. While this will wetbulb below freezing to
support snow, snowflakes will undergo some melting/rounding and
just having a hard time supporting snow ratios above 10:1. If
precipitation intensity is higher than expected, this could yield
slightly higher amounts. Another factor is temperatures are
currently above freezing between Pullman and Lewiston. Local
downsloping this afternoon warmed temperatures into the 40`s.
Dewpoints remain dry enough to support wetbulbing near to below
freezing but not by much and if precip intensity remains light,
this may never occur. On the other end of the spectrum, it is
still only 9PM and precipitation will not arrive until 5AM so
there is still time to cool but increasing clouds does not favor
any big drops.

Further west, a passing trace to hundreth is expected as the
frontal occlusion lifts north. Models do not show much in the way
of QPF from Wenatchee to Omak but dynamics are a bit stronger on
this side of the CWA so will leave some chance for snow with
amounts generally between a trace and tenth. Up to an inch will be
possible in the mountains and across the Cascade Passes.

&&

.AVIATION...
00Z TAFS: Ridge of high pressure keeps VFR conditions prevailing
for most aviation sites until about 09-12Z. A weak warm front
moves through the area spreading a wintry mix of light snow with
some freezing rain possible generally south of I-90 starting as
early as 9Z near KEAT and about 12Z near KGEG vicinity.
Accumulations, if any, are expected to be very light. After the
front moves off Thursday morning...a moist boundary layer with
weak upslope flow will maintain the threat of MVFR ceilings over
the eastern TAF sites. /MJF



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        23  34  31  38  34  42 /  10  70  20  40  90  40
Coeur d`Alene  23  34  32  40  34  41 /  10  70  30  50  90  70
Pullman        31  39  29  42  35  42 /  20  80  20  20  90  70
Lewiston       33  40  31  44  40  47 /  30  80  10  10  80  50
Colville       22  34  26  38  36  42 /   0  30  30  70 100  40
Sandpoint      21  34  30  40  34  41 /   0  50  50  70 100  60
Kellogg        25  34  31  38  34  38 /  10  80  40  50  90  90
Moses Lake     24  35  21  37  31  48 /  40  20  10  70 100  20
Wenatchee      29  39  28  35  33  46 /  50  20  10  80 100  20
Omak           24  36  27  36  31  43 /  10  20  10  80 100  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Central Panhandle Mountains-Northern
     Panhandle.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Northeast Mountains-Okanogan Highlands.

     Winter Storm Watch from Friday morning through late Friday night
     for East Slopes Northern Cascades.

&&

$$






000
FXUS66 KOTX 200503
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
903 PM PST WED NOV 19 2014

.SYNOPSIS...
A weak weather system will arrive late tonight into Thursday with
the potential for a light wintry mix of rain...snow...and freezing
rain. A stronger, wetter and windier weather system will arrive
Friday persisting into the weekend with heavy snow amounts
possible over the mountains. The weather pattern will remain
active through the middle of next week.


&&

.DISCUSSION...

...SLICK TRAVEL EXPECTED OVER SOUTHEASTERN WA ALONG HIGHWAY 26 and
HIGHWAY 12 DUE TO FREEZING RAIN AND SLEET EARLY THURSDAY MORNING...

...A MIX OF LIGHT SNOW AND SLEET POSSIBLE DURING THE MORNING
COMMUTE IN EASTERN WA AND NORTHERN IDAHO...

Evening update: A tricky yet low precipitation event will pass
through the region early Thursday morning and depart in the
afternoon. At this time, it looks like the best chance for
freezing rain mixing with sleet will be over southeastern WA from
northern Garfield County into southwestern Whitman...and southern
Adams County. These areas are currently in the mid 20s and model
profiles are most favorable for a these precipitation types.
Amounts are the unknown factor with the last few runs of the HRRR
simulated reflectivity trending toward the drier NAM. This will
mean the potential ranging from a trace to few hundreths of
liquid. Slick conditions a strong possibility for the Thursday
morning commute but anticipated ice accumulations remains in low
confidence. Nonetheless, Highway 26 and Highway 12 look to carry
the highest threat for icy roads from freezing rain/sleet.

The further north you travel from Pullman to Spokane-CDA-Kellogg-
St Maries. The chance for precipitation to remain as snow becomes
much better. My guess is areas of Benewah/Latah/Kootenai/Shoshone
County will stand the best chance for up to an inch of snow with
less than a half an inch into Spokane, NE WA, and far northern ID
Panhandle. One reason is the lack of QPF but a second will be low
snow ratios. KOTX sounding indicated the top of the inversion
layer around +3C. While this will wetbulb below freezing to
support snow, snowflakes will undergo some melting/rounding and
just having a hard time supporting snow ratios above 10:1. If
precipitation intensity is higher than expected, this could yield
slightly higher amounts. Another factor is temperatures are
currently above freezing between Pullman and Lewiston. Local
downsloping this afternoon warmed temperatures into the 40`s.
Dewpoints remain dry enough to support wetbulbing near to below
freezing but not by much and if precip intensity remains light,
this may never occur. On the other end of the spectrum, it is
still only 9PM and precipitation will not arrive until 5AM so
there is still time to cool but increasing clouds does not favor
any big drops.

Further west, a passing trace to hundreth is expected as the
frontal occlusion lifts north. Models do not show much in the way
of QPF from Wenatchee to Omak but dynamics are a bit stronger on
this side of the CWA so will leave some chance for snow with
amounts generally between a trace and tenth. Up to an inch will be
possible in the mountains and across the Cascade Passes.

&&

.AVIATION...
00Z TAFS: Ridge of high pressure keeps VFR conditions prevailing
for most aviation sites until about 09-12Z. A weak warm front
moves through the area spreading a wintry mix of light snow with
some freezing rain possible generally south of I-90 starting as
early as 9Z near KEAT and about 12Z near KGEG vicinity.
Accumulations, if any, are expected to be very light. After the
front moves off Thursday morning...a moist boundary layer with
weak upslope flow will maintain the threat of MVFR ceilings over
the eastern TAF sites. /MJF



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        23  34  31  38  34  42 /  10  70  20  40  90  40
Coeur d`Alene  23  34  32  40  34  41 /  10  70  30  50  90  70
Pullman        31  39  29  42  35  42 /  20  80  20  20  90  70
Lewiston       33  40  31  44  40  47 /  30  80  10  10  80  50
Colville       22  34  26  38  36  42 /   0  30  30  70 100  40
Sandpoint      21  34  30  40  34  41 /   0  50  50  70 100  60
Kellogg        25  34  31  38  34  38 /  10  80  40  50  90  90
Moses Lake     24  35  21  37  31  48 /  40  20  10  70 100  20
Wenatchee      29  39  28  35  33  46 /  50  20  10  80 100  20
Omak           24  36  27  36  31  43 /  10  20  10  80 100  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Air Stagnation Advisory until Noon PST Friday for Central
     Panhandle Mountains-Coeur d`Alene Area-Idaho Palouse-
     Northern Panhandle.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Central Panhandle Mountains-Northern
     Panhandle.

WA...Air Stagnation Advisory until Noon PST Friday for East Slopes
     Northern Cascades-Lower Garfield and Asotin Counties-Moses
     Lake Area-Northeast Mountains-Okanogan Highlands-Spokane
     Area-Upper Columbia Basin-Washington Palouse-Waterville
     Plateau-Wenatchee Area.

     Winter Storm Watch from Friday afternoon through Saturday
     afternoon for Northeast Mountains-Okanogan Highlands.

     Winter Storm Watch from Friday morning through late Friday night
     for East Slopes Northern Cascades.

&&

$$





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