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000
FXUS66 KOTX 211823
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1123 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
The morning model runs have come into better agreement with the
timing and strength of tonight`s cold front and the trailing upper
trough during the day tomorrow (Wednesday). The GFS continues to
be slower than the other models, but is more progressive than
previous runs. None of the models support much potential for
thunderstorms on Wednesday. The best instability will be shunted
east of the Idaho Panhandle by late morning. The NAM and GFS
forecast a bit of surface based CAPE along the Washington/Canada
border Wednesday afternoon, but the buoyancy on the sounding looks
to be too low in the thermal profile to get much charge
separation (or lightning). In general, this front looks to bring
a cool down, and bit of breeziness, and spotty light showers.
/GKoch

&&

.AVIATION...
18Z TAFS: A high and thin cloud deck is expected through this
evening ahead of a cold front advancing toward the Pacific
Northwest. The front will spill over the Cascades between 00z-03z
and reach the Idaho Panhandle around 06z. This front will largely
be a dry cold front. Scattered light rain showers are expected to
be on the increase after 15z on Wednesday with the arrival of a
trailing cold upper trough. Given the dry post frontal air mass,
we are not anticipating ceiling or visibility restrictions on
Wednesday. The main aviation impact will be increasing west or
southwest winds gusting as high as 20kts on Wednesday. /GKoch



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 211823
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1123 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
The morning model runs have come into better agreement with the
timing and strength of tonight`s cold front and the trailing upper
trough during the day tomorrow (Wednesday). The GFS continues to
be slower than the other models, but is more progressive than
previous runs. None of the models support much potential for
thunderstorms on Wednesday. The best instability will be shunted
east of the Idaho Panhandle by late morning. The NAM and GFS
forecast a bit of surface based CAPE along the Washington/Canada
border Wednesday afternoon, but the buoyancy on the sounding looks
to be too low in the thermal profile to get much charge
separation (or lightning). In general, this front looks to bring
a cool down, and bit of breeziness, and spotty light showers.
/GKoch

&&

.AVIATION...
18Z TAFS: A high and thin cloud deck is expected through this
evening ahead of a cold front advancing toward the Pacific
Northwest. The front will spill over the Cascades between 00z-03z
and reach the Idaho Panhandle around 06z. This front will largely
be a dry cold front. Scattered light rain showers are expected to
be on the increase after 15z on Wednesday with the arrival of a
trailing cold upper trough. Given the dry post frontal air mass,
we are not anticipating ceiling or visibility restrictions on
Wednesday. The main aviation impact will be increasing west or
southwest winds gusting as high as 20kts on Wednesday. /GKoch



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 211823
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1123 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
The morning model runs have come into better agreement with the
timing and strength of tonight`s cold front and the trailing upper
trough during the day tomorrow (Wednesday). The GFS continues to
be slower than the other models, but is more progressive than
previous runs. None of the models support much potential for
thunderstorms on Wednesday. The best instability will be shunted
east of the Idaho Panhandle by late morning. The NAM and GFS
forecast a bit of surface based CAPE along the Washington/Canada
border Wednesday afternoon, but the buoyancy on the sounding looks
to be too low in the thermal profile to get much charge
separation (or lightning). In general, this front looks to bring
a cool down, and bit of breeziness, and spotty light showers.
/GKoch

&&

.AVIATION...
18Z TAFS: A high and thin cloud deck is expected through this
evening ahead of a cold front advancing toward the Pacific
Northwest. The front will spill over the Cascades between 00z-03z
and reach the Idaho Panhandle around 06z. This front will largely
be a dry cold front. Scattered light rain showers are expected to
be on the increase after 15z on Wednesday with the arrival of a
trailing cold upper trough. Given the dry post frontal air mass,
we are not anticipating ceiling or visibility restrictions on
Wednesday. The main aviation impact will be increasing west or
southwest winds gusting as high as 20kts on Wednesday. /GKoch



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 211823
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1123 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
The morning model runs have come into better agreement with the
timing and strength of tonight`s cold front and the trailing upper
trough during the day tomorrow (Wednesday). The GFS continues to
be slower than the other models, but is more progressive than
previous runs. None of the models support much potential for
thunderstorms on Wednesday. The best instability will be shunted
east of the Idaho Panhandle by late morning. The NAM and GFS
forecast a bit of surface based CAPE along the Washington/Canada
border Wednesday afternoon, but the buoyancy on the sounding looks
to be too low in the thermal profile to get much charge
separation (or lightning). In general, this front looks to bring
a cool down, and bit of breeziness, and spotty light showers.
/GKoch

&&

.AVIATION...
18Z TAFS: A high and thin cloud deck is expected through this
evening ahead of a cold front advancing toward the Pacific
Northwest. The front will spill over the Cascades between 00z-03z
and reach the Idaho Panhandle around 06z. This front will largely
be a dry cold front. Scattered light rain showers are expected to
be on the increase after 15z on Wednesday with the arrival of a
trailing cold upper trough. Given the dry post frontal air mass,
we are not anticipating ceiling or visibility restrictions on
Wednesday. The main aviation impact will be increasing west or
southwest winds gusting as high as 20kts on Wednesday. /GKoch



&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




  [top]

000
FXUS66 KPQR 211617
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
909 AM PDT TUE APR 21 2015

.SYNOPSIS...A SERIES OF WEAK FRONTS WILL BRING A FEW LIGHT SHOWERS
AND DRIZZLE TO MAINLY THE COAST AND CASCADES THROUGH FRIDAY...BUT
MOST LOCATIONS LOOK TO REMAIN DRY THROUGH THIS PERIOD WITH
TEMPERATURES NEAR AVERAGE. A WETTER STORM SYSTEM WILL MOVE INTO THE
AREA THIS WEEKEND...WITH POSSIBLY MORE WET WET WEATHER EARLY NEXT
WEEK.

&&

.SHORT TERM...TODAY THROUGH FRIDAY...VISIBLE SATELLITE IMAGERY
REVEALS MARINE CLOUDS HAVE PUSHED INTO THE COAST RANGE AND UP THE
COLUMBIA RIVER TO PORTLAND. THE MOIST LOW LEVELS AND NORTHWEST FLOW
HAVE PRODUCED PERIODS OF DRIZZLE AROUND ASTORIA THIS MORNING. FARTHER
SOUTH ALONG THE CENTRAL OREGON COAST...THE FLOW IS A LITTLE MORE
NORTHERLY SO DRIZZLE REPORTS HAVE BEEN MORE SPARSE. EXPECT AREAS OF
DRIZZLE TO CONTINUE THROUGH AT LEAST MIDDAY ALONG THE
COAST...ESPECIALLY NORTH OF TILLAMOOK.

SATELLITE AND KLGX RADAR ALSO SHOW A BAND OF SHOWERS ASSOCIATED WITH
A WEAK FRONT OFF THE PACIFIC NORTHWEST COAST. BASED ON MODEL OUTPUT
THESE SHOWERS SHOULD WEAKEN AS THEY APPROACH THE REGION...BUT COULD
STILL BRING A PERIOD OF LIGHT RAIN LATER TODAY. LINEAR EXTRAPOLATION
WOULD PLACE THESE SHOWERS OVER THE COAST TOWARDS MID AFTERNOON AND
THIS EVENING OVER THE WILLAMETTE VALLEY. AS A RESULT...THE POP
FORECAST WAS TRENDED TOWARDS THIS GENERAL IDEA. PRESSURE GRADIENTS
WILL ALSO INCREASE DURING THIS PERIOD SO EXPECT BREEZY WEST TO
NORTHWEST WINDS OF 15 TO 25 MPH NEAR THE GAPS IN THE COAST RANGE AND
CENTRAL COLUMBIA RIVER GORGE.

MODEL QPF FIELDS ARE SOMEWHAT CHAOTIC AND HARD TO DIAGNOSE LATER
TONIGHT AND EARLY WEDNESDAY IN THE POST FRONTAL AIRMASS.
HOWEVER...MODEL SOUNDINGS SHOW A SHALLOW LAYER OF
INSTABILITY...GENERALLY UNDER 850MB...MOVING INTO THE REGION LATER
TONIGHT AND EARLY WEDNESDAY. THIS SEEMS REASONABLE GIVEN THE LARGE
POST FRONTAL CUMULUS FIELD NEAR 130W VISIBLE ON SATELLITE IMAGERY.
GIVEN THE FLOW WILL REMAIN ONSHORE DURING THIS PERIOD...POPS WERE
INCREASED ALONG THE COAST AND COAST RANGE FOR THIS PERIOD EVEN
THOUGH MODEL QPF FIELDS ARE MEAGER AT BEST. REGARDLES...ANY SHOWERS
SHOULD BE SHALLOW ENOUGH THAT THEY WILL HAVE A HARD TIME CROSSING
THE COAST RANGE SO VALLEY POPS WERE GENERALLY LEFT BELOW SLIGHT
CHANCE CRITERIA.

SURFACE HIGH PRESSURE WILL SHIFT NORTHWARD INTO WESTERN WASHINGTON
ON WEDNESDAY...WHICH SHOULD ALLOW THE SOUTHERN PORTIONS OF THE
AREA...INCLUDING THE COAST...TO CLEAR MORE EFFICIENTLY THE NORTHERN
HALF OF THE CWA WEDNESDAY AFTERNOON. SHORTWAVE RIDGING SHOULD KEEP
THE AREA DRY THROUGH WEDNESDAY NIGHT/EARLY THURSDAY.  ANOTHER
WEAKENING FRONT WILL MOVE FROM NORTHWEST TO SOUTHEAST ACROSS THE
AREA LATE THURSDAY...BRINGING A DECENT CHANCE OF LIGHT SHOWERS WITH
IT.

ADDITIONAL ONSHORE FLOW UNDER A WEAK UPPER LEVEL SHORTWAVE TROUGH
MAY ALLOW A FEW MORE SHOWERS TO MOVE INTO THE AREA ON FRIDAY AS
WELL...BUT MODEL DIFFERENCES CONTINUE TO RESULT IN INCREASED
UNCERTAINTY. TEMPERATURES LOOK TO REMAIN NEAR AVERAGE THROUGH THE
SHORT TERM. /NEUMAN


.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...PREVIOUS DISCUSSION
BELOW...MODELS CONTINUE TO STRUGGLE ON THE DETAILS...BUT SUGGEST A
WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD ACROSS THE AREA
LATE SATURDAY THROUGH SUNDAY NIGHT. AS A RESULT...POPS WERE INCREASED
IN THE LIKELY TO CATEGORICAL RANGE FOR THE PRIME WINDOW OF SATURDAY
NIGHT AND SUNDAY. BOTH MODELS SUGGEST ANOTHER STORM SYSTEM IS LIKELY
NEXT WEEK...BUT ONCE AGAIN DIFFER ON TIMING SO POPS WERE TRENDED MORE
INTO THE HIGH END CHANCE TO LOW END LIKELY RANGE. /NEUMAN

&&

.AVIATION...APPROACHING WEAK FRONT WILL CONTINUE TO PUSH MVFR
STRATUS ALONG THE COAST AND INLAND THROUGH THIS EVENING. EXPECT
CIGS 1000-1500 FT ALONG THE COAST THROUGH AT LEAST 00Z WED...WHILE
INLAND SITES WILL SEE CIGS AROUND 1500-2000 FT THROUGH 22Z TUE.
WESTERLY ONSHORE FLOW MAY RETAIN OCCASIONAL MOUNTAIN OBSCURATION
THROUGH THIS EVENING. CIGS LIFT BRIEFLY TO HIGH END MVFR/LOW END
VFR AFTER 00Z WED...THEN RETURN TO MVFR AFTER 10Z WED.

KPDX AND APPROACHES...MVFR STRATUS AROUND 2000 FT AFFECTING THE
TERMINAL THROUGH 20Z-21Z TUE. VFR RETURNS BY 23Z TUE WITH NW
WINDS PICKING UP MID AFTERNOON INTO EARLY EVENING. AFTER VFR CIGS
THROUGH THIS EVENING...MVFR CIGS AROUND 2500 FT RETURN BETWEEN
10-12Z WED. /27

&&

.MARINE...WEAK FRONT MOVING THROUGH THE COASTAL WATERS EARLY TODAY
WILL INCREASE NWLY WINDS INTO THE SMALL CRAFT ADVISORY CATEGORY
WITH GUSTS 25-30 KTS...WHICH SHOULD LAST INTO WED MORNING. A MUCH
STRONGER FRONT LOOKS TO MOVE ACROSS THE WATERS OVER THE WEEKEND
AND WILL LIKELY BRING GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF
BUILDING SEAS.

SEAS WILL ALSO INCREASE WITH NWLY SWELL EXCEEDING 10 FT LATER THIS
AFTERNOON AND PEAK AROUND 10 TO 12 FT TONIGHT BEFORE SUBSIDING
BELOW 10 FT WED EVENING. THIS WILL LEAD TO ROUGH COLUMBIA RIVER
BAR DURING THE NEXT FEW EBBS. WILL HAVE TO WATCH THE TONIGHT
PERIOD IF SEAS RISE A LITTLE HIGHER THAN ANTICIPATED ROUGH
COLUMBIA RIVER BAR CONDITIONS MAY OCCUR DURING NON EBB TIME.
/MH/27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PDT WEDNESDAY FOR
     WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10
     TO 60 NM-WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO
     60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM THIS
     AFTERNOON TO 6 PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE
     SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PDT WEDNESDAY FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR
     OUT 10 NM-COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OR
     OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10
     AM PDT THIS MORNING...FROM 7 PM TO 10 PM PDT THIS EVENING...
     THEN FROM 5 AM TO 10 AM PDT WEDNESDAY.

&&


$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 211617
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
909 AM PDT TUE APR 21 2015

.SYNOPSIS...A SERIES OF WEAK FRONTS WILL BRING A FEW LIGHT SHOWERS
AND DRIZZLE TO MAINLY THE COAST AND CASCADES THROUGH FRIDAY...BUT
MOST LOCATIONS LOOK TO REMAIN DRY THROUGH THIS PERIOD WITH
TEMPERATURES NEAR AVERAGE. A WETTER STORM SYSTEM WILL MOVE INTO THE
AREA THIS WEEKEND...WITH POSSIBLY MORE WET WET WEATHER EARLY NEXT
WEEK.

&&

.SHORT TERM...TODAY THROUGH FRIDAY...VISIBLE SATELLITE IMAGERY
REVEALS MARINE CLOUDS HAVE PUSHED INTO THE COAST RANGE AND UP THE
COLUMBIA RIVER TO PORTLAND. THE MOIST LOW LEVELS AND NORTHWEST FLOW
HAVE PRODUCED PERIODS OF DRIZZLE AROUND ASTORIA THIS MORNING. FARTHER
SOUTH ALONG THE CENTRAL OREGON COAST...THE FLOW IS A LITTLE MORE
NORTHERLY SO DRIZZLE REPORTS HAVE BEEN MORE SPARSE. EXPECT AREAS OF
DRIZZLE TO CONTINUE THROUGH AT LEAST MIDDAY ALONG THE
COAST...ESPECIALLY NORTH OF TILLAMOOK.

SATELLITE AND KLGX RADAR ALSO SHOW A BAND OF SHOWERS ASSOCIATED WITH
A WEAK FRONT OFF THE PACIFIC NORTHWEST COAST. BASED ON MODEL OUTPUT
THESE SHOWERS SHOULD WEAKEN AS THEY APPROACH THE REGION...BUT COULD
STILL BRING A PERIOD OF LIGHT RAIN LATER TODAY. LINEAR EXTRAPOLATION
WOULD PLACE THESE SHOWERS OVER THE COAST TOWARDS MID AFTERNOON AND
THIS EVENING OVER THE WILLAMETTE VALLEY. AS A RESULT...THE POP
FORECAST WAS TRENDED TOWARDS THIS GENERAL IDEA. PRESSURE GRADIENTS
WILL ALSO INCREASE DURING THIS PERIOD SO EXPECT BREEZY WEST TO
NORTHWEST WINDS OF 15 TO 25 MPH NEAR THE GAPS IN THE COAST RANGE AND
CENTRAL COLUMBIA RIVER GORGE.

MODEL QPF FIELDS ARE SOMEWHAT CHAOTIC AND HARD TO DIAGNOSE LATER
TONIGHT AND EARLY WEDNESDAY IN THE POST FRONTAL AIRMASS.
HOWEVER...MODEL SOUNDINGS SHOW A SHALLOW LAYER OF
INSTABILITY...GENERALLY UNDER 850MB...MOVING INTO THE REGION LATER
TONIGHT AND EARLY WEDNESDAY. THIS SEEMS REASONABLE GIVEN THE LARGE
POST FRONTAL CUMULUS FIELD NEAR 130W VISIBLE ON SATELLITE IMAGERY.
GIVEN THE FLOW WILL REMAIN ONSHORE DURING THIS PERIOD...POPS WERE
INCREASED ALONG THE COAST AND COAST RANGE FOR THIS PERIOD EVEN
THOUGH MODEL QPF FIELDS ARE MEAGER AT BEST. REGARDLES...ANY SHOWERS
SHOULD BE SHALLOW ENOUGH THAT THEY WILL HAVE A HARD TIME CROSSING
THE COAST RANGE SO VALLEY POPS WERE GENERALLY LEFT BELOW SLIGHT
CHANCE CRITERIA.

SURFACE HIGH PRESSURE WILL SHIFT NORTHWARD INTO WESTERN WASHINGTON
ON WEDNESDAY...WHICH SHOULD ALLOW THE SOUTHERN PORTIONS OF THE
AREA...INCLUDING THE COAST...TO CLEAR MORE EFFICIENTLY THE NORTHERN
HALF OF THE CWA WEDNESDAY AFTERNOON. SHORTWAVE RIDGING SHOULD KEEP
THE AREA DRY THROUGH WEDNESDAY NIGHT/EARLY THURSDAY.  ANOTHER
WEAKENING FRONT WILL MOVE FROM NORTHWEST TO SOUTHEAST ACROSS THE
AREA LATE THURSDAY...BRINGING A DECENT CHANCE OF LIGHT SHOWERS WITH
IT.

ADDITIONAL ONSHORE FLOW UNDER A WEAK UPPER LEVEL SHORTWAVE TROUGH
MAY ALLOW A FEW MORE SHOWERS TO MOVE INTO THE AREA ON FRIDAY AS
WELL...BUT MODEL DIFFERENCES CONTINUE TO RESULT IN INCREASED
UNCERTAINTY. TEMPERATURES LOOK TO REMAIN NEAR AVERAGE THROUGH THE
SHORT TERM. /NEUMAN


.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...PREVIOUS DISCUSSION
BELOW...MODELS CONTINUE TO STRUGGLE ON THE DETAILS...BUT SUGGEST A
WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD ACROSS THE AREA
LATE SATURDAY THROUGH SUNDAY NIGHT. AS A RESULT...POPS WERE INCREASED
IN THE LIKELY TO CATEGORICAL RANGE FOR THE PRIME WINDOW OF SATURDAY
NIGHT AND SUNDAY. BOTH MODELS SUGGEST ANOTHER STORM SYSTEM IS LIKELY
NEXT WEEK...BUT ONCE AGAIN DIFFER ON TIMING SO POPS WERE TRENDED MORE
INTO THE HIGH END CHANCE TO LOW END LIKELY RANGE. /NEUMAN

&&

.AVIATION...APPROACHING WEAK FRONT WILL CONTINUE TO PUSH MVFR
STRATUS ALONG THE COAST AND INLAND THROUGH THIS EVENING. EXPECT
CIGS 1000-1500 FT ALONG THE COAST THROUGH AT LEAST 00Z WED...WHILE
INLAND SITES WILL SEE CIGS AROUND 1500-2000 FT THROUGH 22Z TUE.
WESTERLY ONSHORE FLOW MAY RETAIN OCCASIONAL MOUNTAIN OBSCURATION
THROUGH THIS EVENING. CIGS LIFT BRIEFLY TO HIGH END MVFR/LOW END
VFR AFTER 00Z WED...THEN RETURN TO MVFR AFTER 10Z WED.

KPDX AND APPROACHES...MVFR STRATUS AROUND 2000 FT AFFECTING THE
TERMINAL THROUGH 20Z-21Z TUE. VFR RETURNS BY 23Z TUE WITH NW
WINDS PICKING UP MID AFTERNOON INTO EARLY EVENING. AFTER VFR CIGS
THROUGH THIS EVENING...MVFR CIGS AROUND 2500 FT RETURN BETWEEN
10-12Z WED. /27

&&

.MARINE...WEAK FRONT MOVING THROUGH THE COASTAL WATERS EARLY TODAY
WILL INCREASE NWLY WINDS INTO THE SMALL CRAFT ADVISORY CATEGORY
WITH GUSTS 25-30 KTS...WHICH SHOULD LAST INTO WED MORNING. A MUCH
STRONGER FRONT LOOKS TO MOVE ACROSS THE WATERS OVER THE WEEKEND
AND WILL LIKELY BRING GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF
BUILDING SEAS.

SEAS WILL ALSO INCREASE WITH NWLY SWELL EXCEEDING 10 FT LATER THIS
AFTERNOON AND PEAK AROUND 10 TO 12 FT TONIGHT BEFORE SUBSIDING
BELOW 10 FT WED EVENING. THIS WILL LEAD TO ROUGH COLUMBIA RIVER
BAR DURING THE NEXT FEW EBBS. WILL HAVE TO WATCH THE TONIGHT
PERIOD IF SEAS RISE A LITTLE HIGHER THAN ANTICIPATED ROUGH
COLUMBIA RIVER BAR CONDITIONS MAY OCCUR DURING NON EBB TIME.
/MH/27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PDT WEDNESDAY FOR
     WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10
     TO 60 NM-WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO
     60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM THIS
     AFTERNOON TO 6 PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE
     SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PDT WEDNESDAY FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR
     OUT 10 NM-COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OR
     OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10
     AM PDT THIS MORNING...FROM 7 PM TO 10 PM PDT THIS EVENING...
     THEN FROM 5 AM TO 10 AM PDT WEDNESDAY.

&&


$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 211617
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
909 AM PDT TUE APR 21 2015

.SYNOPSIS...A SERIES OF WEAK FRONTS WILL BRING A FEW LIGHT SHOWERS
AND DRIZZLE TO MAINLY THE COAST AND CASCADES THROUGH FRIDAY...BUT
MOST LOCATIONS LOOK TO REMAIN DRY THROUGH THIS PERIOD WITH
TEMPERATURES NEAR AVERAGE. A WETTER STORM SYSTEM WILL MOVE INTO THE
AREA THIS WEEKEND...WITH POSSIBLY MORE WET WET WEATHER EARLY NEXT
WEEK.

&&

.SHORT TERM...TODAY THROUGH FRIDAY...VISIBLE SATELLITE IMAGERY
REVEALS MARINE CLOUDS HAVE PUSHED INTO THE COAST RANGE AND UP THE
COLUMBIA RIVER TO PORTLAND. THE MOIST LOW LEVELS AND NORTHWEST FLOW
HAVE PRODUCED PERIODS OF DRIZZLE AROUND ASTORIA THIS MORNING. FARTHER
SOUTH ALONG THE CENTRAL OREGON COAST...THE FLOW IS A LITTLE MORE
NORTHERLY SO DRIZZLE REPORTS HAVE BEEN MORE SPARSE. EXPECT AREAS OF
DRIZZLE TO CONTINUE THROUGH AT LEAST MIDDAY ALONG THE
COAST...ESPECIALLY NORTH OF TILLAMOOK.

SATELLITE AND KLGX RADAR ALSO SHOW A BAND OF SHOWERS ASSOCIATED WITH
A WEAK FRONT OFF THE PACIFIC NORTHWEST COAST. BASED ON MODEL OUTPUT
THESE SHOWERS SHOULD WEAKEN AS THEY APPROACH THE REGION...BUT COULD
STILL BRING A PERIOD OF LIGHT RAIN LATER TODAY. LINEAR EXTRAPOLATION
WOULD PLACE THESE SHOWERS OVER THE COAST TOWARDS MID AFTERNOON AND
THIS EVENING OVER THE WILLAMETTE VALLEY. AS A RESULT...THE POP
FORECAST WAS TRENDED TOWARDS THIS GENERAL IDEA. PRESSURE GRADIENTS
WILL ALSO INCREASE DURING THIS PERIOD SO EXPECT BREEZY WEST TO
NORTHWEST WINDS OF 15 TO 25 MPH NEAR THE GAPS IN THE COAST RANGE AND
CENTRAL COLUMBIA RIVER GORGE.

MODEL QPF FIELDS ARE SOMEWHAT CHAOTIC AND HARD TO DIAGNOSE LATER
TONIGHT AND EARLY WEDNESDAY IN THE POST FRONTAL AIRMASS.
HOWEVER...MODEL SOUNDINGS SHOW A SHALLOW LAYER OF
INSTABILITY...GENERALLY UNDER 850MB...MOVING INTO THE REGION LATER
TONIGHT AND EARLY WEDNESDAY. THIS SEEMS REASONABLE GIVEN THE LARGE
POST FRONTAL CUMULUS FIELD NEAR 130W VISIBLE ON SATELLITE IMAGERY.
GIVEN THE FLOW WILL REMAIN ONSHORE DURING THIS PERIOD...POPS WERE
INCREASED ALONG THE COAST AND COAST RANGE FOR THIS PERIOD EVEN
THOUGH MODEL QPF FIELDS ARE MEAGER AT BEST. REGARDLES...ANY SHOWERS
SHOULD BE SHALLOW ENOUGH THAT THEY WILL HAVE A HARD TIME CROSSING
THE COAST RANGE SO VALLEY POPS WERE GENERALLY LEFT BELOW SLIGHT
CHANCE CRITERIA.

SURFACE HIGH PRESSURE WILL SHIFT NORTHWARD INTO WESTERN WASHINGTON
ON WEDNESDAY...WHICH SHOULD ALLOW THE SOUTHERN PORTIONS OF THE
AREA...INCLUDING THE COAST...TO CLEAR MORE EFFICIENTLY THE NORTHERN
HALF OF THE CWA WEDNESDAY AFTERNOON. SHORTWAVE RIDGING SHOULD KEEP
THE AREA DRY THROUGH WEDNESDAY NIGHT/EARLY THURSDAY.  ANOTHER
WEAKENING FRONT WILL MOVE FROM NORTHWEST TO SOUTHEAST ACROSS THE
AREA LATE THURSDAY...BRINGING A DECENT CHANCE OF LIGHT SHOWERS WITH
IT.

ADDITIONAL ONSHORE FLOW UNDER A WEAK UPPER LEVEL SHORTWAVE TROUGH
MAY ALLOW A FEW MORE SHOWERS TO MOVE INTO THE AREA ON FRIDAY AS
WELL...BUT MODEL DIFFERENCES CONTINUE TO RESULT IN INCREASED
UNCERTAINTY. TEMPERATURES LOOK TO REMAIN NEAR AVERAGE THROUGH THE
SHORT TERM. /NEUMAN


.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...PREVIOUS DISCUSSION
BELOW...MODELS CONTINUE TO STRUGGLE ON THE DETAILS...BUT SUGGEST A
WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD ACROSS THE AREA
LATE SATURDAY THROUGH SUNDAY NIGHT. AS A RESULT...POPS WERE INCREASED
IN THE LIKELY TO CATEGORICAL RANGE FOR THE PRIME WINDOW OF SATURDAY
NIGHT AND SUNDAY. BOTH MODELS SUGGEST ANOTHER STORM SYSTEM IS LIKELY
NEXT WEEK...BUT ONCE AGAIN DIFFER ON TIMING SO POPS WERE TRENDED MORE
INTO THE HIGH END CHANCE TO LOW END LIKELY RANGE. /NEUMAN

&&

.AVIATION...APPROACHING WEAK FRONT WILL CONTINUE TO PUSH MVFR
STRATUS ALONG THE COAST AND INLAND THROUGH THIS EVENING. EXPECT
CIGS 1000-1500 FT ALONG THE COAST THROUGH AT LEAST 00Z WED...WHILE
INLAND SITES WILL SEE CIGS AROUND 1500-2000 FT THROUGH 22Z TUE.
WESTERLY ONSHORE FLOW MAY RETAIN OCCASIONAL MOUNTAIN OBSCURATION
THROUGH THIS EVENING. CIGS LIFT BRIEFLY TO HIGH END MVFR/LOW END
VFR AFTER 00Z WED...THEN RETURN TO MVFR AFTER 10Z WED.

KPDX AND APPROACHES...MVFR STRATUS AROUND 2000 FT AFFECTING THE
TERMINAL THROUGH 20Z-21Z TUE. VFR RETURNS BY 23Z TUE WITH NW
WINDS PICKING UP MID AFTERNOON INTO EARLY EVENING. AFTER VFR CIGS
THROUGH THIS EVENING...MVFR CIGS AROUND 2500 FT RETURN BETWEEN
10-12Z WED. /27

&&

.MARINE...WEAK FRONT MOVING THROUGH THE COASTAL WATERS EARLY TODAY
WILL INCREASE NWLY WINDS INTO THE SMALL CRAFT ADVISORY CATEGORY
WITH GUSTS 25-30 KTS...WHICH SHOULD LAST INTO WED MORNING. A MUCH
STRONGER FRONT LOOKS TO MOVE ACROSS THE WATERS OVER THE WEEKEND
AND WILL LIKELY BRING GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF
BUILDING SEAS.

SEAS WILL ALSO INCREASE WITH NWLY SWELL EXCEEDING 10 FT LATER THIS
AFTERNOON AND PEAK AROUND 10 TO 12 FT TONIGHT BEFORE SUBSIDING
BELOW 10 FT WED EVENING. THIS WILL LEAD TO ROUGH COLUMBIA RIVER
BAR DURING THE NEXT FEW EBBS. WILL HAVE TO WATCH THE TONIGHT
PERIOD IF SEAS RISE A LITTLE HIGHER THAN ANTICIPATED ROUGH
COLUMBIA RIVER BAR CONDITIONS MAY OCCUR DURING NON EBB TIME.
/MH/27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PDT WEDNESDAY FOR
     WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10
     TO 60 NM-WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO
     60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM THIS
     AFTERNOON TO 6 PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE
     SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PDT WEDNESDAY FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR
     OUT 10 NM-COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OR
     OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10
     AM PDT THIS MORNING...FROM 7 PM TO 10 PM PDT THIS EVENING...
     THEN FROM 5 AM TO 10 AM PDT WEDNESDAY.

&&


$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 211617
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
909 AM PDT TUE APR 21 2015

.SYNOPSIS...A SERIES OF WEAK FRONTS WILL BRING A FEW LIGHT SHOWERS
AND DRIZZLE TO MAINLY THE COAST AND CASCADES THROUGH FRIDAY...BUT
MOST LOCATIONS LOOK TO REMAIN DRY THROUGH THIS PERIOD WITH
TEMPERATURES NEAR AVERAGE. A WETTER STORM SYSTEM WILL MOVE INTO THE
AREA THIS WEEKEND...WITH POSSIBLY MORE WET WET WEATHER EARLY NEXT
WEEK.

&&

.SHORT TERM...TODAY THROUGH FRIDAY...VISIBLE SATELLITE IMAGERY
REVEALS MARINE CLOUDS HAVE PUSHED INTO THE COAST RANGE AND UP THE
COLUMBIA RIVER TO PORTLAND. THE MOIST LOW LEVELS AND NORTHWEST FLOW
HAVE PRODUCED PERIODS OF DRIZZLE AROUND ASTORIA THIS MORNING. FARTHER
SOUTH ALONG THE CENTRAL OREGON COAST...THE FLOW IS A LITTLE MORE
NORTHERLY SO DRIZZLE REPORTS HAVE BEEN MORE SPARSE. EXPECT AREAS OF
DRIZZLE TO CONTINUE THROUGH AT LEAST MIDDAY ALONG THE
COAST...ESPECIALLY NORTH OF TILLAMOOK.

SATELLITE AND KLGX RADAR ALSO SHOW A BAND OF SHOWERS ASSOCIATED WITH
A WEAK FRONT OFF THE PACIFIC NORTHWEST COAST. BASED ON MODEL OUTPUT
THESE SHOWERS SHOULD WEAKEN AS THEY APPROACH THE REGION...BUT COULD
STILL BRING A PERIOD OF LIGHT RAIN LATER TODAY. LINEAR EXTRAPOLATION
WOULD PLACE THESE SHOWERS OVER THE COAST TOWARDS MID AFTERNOON AND
THIS EVENING OVER THE WILLAMETTE VALLEY. AS A RESULT...THE POP
FORECAST WAS TRENDED TOWARDS THIS GENERAL IDEA. PRESSURE GRADIENTS
WILL ALSO INCREASE DURING THIS PERIOD SO EXPECT BREEZY WEST TO
NORTHWEST WINDS OF 15 TO 25 MPH NEAR THE GAPS IN THE COAST RANGE AND
CENTRAL COLUMBIA RIVER GORGE.

MODEL QPF FIELDS ARE SOMEWHAT CHAOTIC AND HARD TO DIAGNOSE LATER
TONIGHT AND EARLY WEDNESDAY IN THE POST FRONTAL AIRMASS.
HOWEVER...MODEL SOUNDINGS SHOW A SHALLOW LAYER OF
INSTABILITY...GENERALLY UNDER 850MB...MOVING INTO THE REGION LATER
TONIGHT AND EARLY WEDNESDAY. THIS SEEMS REASONABLE GIVEN THE LARGE
POST FRONTAL CUMULUS FIELD NEAR 130W VISIBLE ON SATELLITE IMAGERY.
GIVEN THE FLOW WILL REMAIN ONSHORE DURING THIS PERIOD...POPS WERE
INCREASED ALONG THE COAST AND COAST RANGE FOR THIS PERIOD EVEN
THOUGH MODEL QPF FIELDS ARE MEAGER AT BEST. REGARDLES...ANY SHOWERS
SHOULD BE SHALLOW ENOUGH THAT THEY WILL HAVE A HARD TIME CROSSING
THE COAST RANGE SO VALLEY POPS WERE GENERALLY LEFT BELOW SLIGHT
CHANCE CRITERIA.

SURFACE HIGH PRESSURE WILL SHIFT NORTHWARD INTO WESTERN WASHINGTON
ON WEDNESDAY...WHICH SHOULD ALLOW THE SOUTHERN PORTIONS OF THE
AREA...INCLUDING THE COAST...TO CLEAR MORE EFFICIENTLY THE NORTHERN
HALF OF THE CWA WEDNESDAY AFTERNOON. SHORTWAVE RIDGING SHOULD KEEP
THE AREA DRY THROUGH WEDNESDAY NIGHT/EARLY THURSDAY.  ANOTHER
WEAKENING FRONT WILL MOVE FROM NORTHWEST TO SOUTHEAST ACROSS THE
AREA LATE THURSDAY...BRINGING A DECENT CHANCE OF LIGHT SHOWERS WITH
IT.

ADDITIONAL ONSHORE FLOW UNDER A WEAK UPPER LEVEL SHORTWAVE TROUGH
MAY ALLOW A FEW MORE SHOWERS TO MOVE INTO THE AREA ON FRIDAY AS
WELL...BUT MODEL DIFFERENCES CONTINUE TO RESULT IN INCREASED
UNCERTAINTY. TEMPERATURES LOOK TO REMAIN NEAR AVERAGE THROUGH THE
SHORT TERM. /NEUMAN


.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...PREVIOUS DISCUSSION
BELOW...MODELS CONTINUE TO STRUGGLE ON THE DETAILS...BUT SUGGEST A
WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD ACROSS THE AREA
LATE SATURDAY THROUGH SUNDAY NIGHT. AS A RESULT...POPS WERE INCREASED
IN THE LIKELY TO CATEGORICAL RANGE FOR THE PRIME WINDOW OF SATURDAY
NIGHT AND SUNDAY. BOTH MODELS SUGGEST ANOTHER STORM SYSTEM IS LIKELY
NEXT WEEK...BUT ONCE AGAIN DIFFER ON TIMING SO POPS WERE TRENDED MORE
INTO THE HIGH END CHANCE TO LOW END LIKELY RANGE. /NEUMAN

&&

.AVIATION...APPROACHING WEAK FRONT WILL CONTINUE TO PUSH MVFR
STRATUS ALONG THE COAST AND INLAND THROUGH THIS EVENING. EXPECT
CIGS 1000-1500 FT ALONG THE COAST THROUGH AT LEAST 00Z WED...WHILE
INLAND SITES WILL SEE CIGS AROUND 1500-2000 FT THROUGH 22Z TUE.
WESTERLY ONSHORE FLOW MAY RETAIN OCCASIONAL MOUNTAIN OBSCURATION
THROUGH THIS EVENING. CIGS LIFT BRIEFLY TO HIGH END MVFR/LOW END
VFR AFTER 00Z WED...THEN RETURN TO MVFR AFTER 10Z WED.

KPDX AND APPROACHES...MVFR STRATUS AROUND 2000 FT AFFECTING THE
TERMINAL THROUGH 20Z-21Z TUE. VFR RETURNS BY 23Z TUE WITH NW
WINDS PICKING UP MID AFTERNOON INTO EARLY EVENING. AFTER VFR CIGS
THROUGH THIS EVENING...MVFR CIGS AROUND 2500 FT RETURN BETWEEN
10-12Z WED. /27

&&

.MARINE...WEAK FRONT MOVING THROUGH THE COASTAL WATERS EARLY TODAY
WILL INCREASE NWLY WINDS INTO THE SMALL CRAFT ADVISORY CATEGORY
WITH GUSTS 25-30 KTS...WHICH SHOULD LAST INTO WED MORNING. A MUCH
STRONGER FRONT LOOKS TO MOVE ACROSS THE WATERS OVER THE WEEKEND
AND WILL LIKELY BRING GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF
BUILDING SEAS.

SEAS WILL ALSO INCREASE WITH NWLY SWELL EXCEEDING 10 FT LATER THIS
AFTERNOON AND PEAK AROUND 10 TO 12 FT TONIGHT BEFORE SUBSIDING
BELOW 10 FT WED EVENING. THIS WILL LEAD TO ROUGH COLUMBIA RIVER
BAR DURING THE NEXT FEW EBBS. WILL HAVE TO WATCH THE TONIGHT
PERIOD IF SEAS RISE A LITTLE HIGHER THAN ANTICIPATED ROUGH
COLUMBIA RIVER BAR CONDITIONS MAY OCCUR DURING NON EBB TIME.
/MH/27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PDT WEDNESDAY FOR
     WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10
     TO 60 NM-WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO
     60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM THIS
     AFTERNOON TO 6 PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE
     SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PDT WEDNESDAY FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR
     OUT 10 NM-COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OR
     OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10
     AM PDT THIS MORNING...FROM 7 PM TO 10 PM PDT THIS EVENING...
     THEN FROM 5 AM TO 10 AM PDT WEDNESDAY.

&&


$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.


  [top]

000
FXUS66 KSEW 211522
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
830 AM PDT TUE APR 21 2015

.SYNOPSIS...A COLD FRONT WILL MOVE INLAND THIS AFTERNOON AND EVENING
BRINGING AN ABRUPT CHANGE IN THE WEATHER. COOL AND LOCALLY WINDY
CONDITIONS WITH SHOWERS ARE LIKELY TONIGHT INTO WEDNESDAY. SNOW
LEVELS WILL FALL TONIGHT AND WEDNESDAY IN THE MOUNTAINS. A WEAK
FRONT WILL ARRIVE THURSDAY BRINGING A CHANCE OF RAIN. MOIST
SOUTHWEST FLOW ALOFT WILL BRING PERIODS OF RAIN NEXT WEEKEND.

&&

.SHORT TERM...STRATUS HAS PUSHED INTO THE SOUTHWEST AND THERE ARE
PATCHES NEAR THE STRAIT AS WELL. A FRONT OFFSHORE THIS MORNING WILL
MOVE INLAND THIS AFTERNOON AND EVENING. STRONG ONSHORE FLOW BEHIND
THE FRONT WILL BRING WINDY CONDITIONS TO A FEW ZONES NEAR THE STRAIT
AND A WIND ADVISORY IS IN EFFECT FOR THE ADMIRALTY INLET AREA. POPS
RANGE FROM CHANCE TO LIKELY TONIGHT. A PUGET SOUND CONVERGENCE ZONE
IS LIKELY TO FORM TONIGHT OVER SNOHOMISH AND KING COUNTIES AND IT
WILL LAST INTO WEDNESDAY. HIGHS WILL BE IN THE LOW 60S TODAY THEN
FALL SEVERAL DEGREES TOMORROW.

WEDNESDAY WILL BE CLOUDY UNDER CONTINUED ONSHORE FLOW BUT SOME
CLEARING MAY OCCUR WEDNESDAY NIGHT AS AN UPPER AND SURFACE RIDGE
TEMPORARILY BUILDS. SHOWERS ARE FORECAST TO TAPER CONSIDERABLY
WEDNESDAY NIGHT. CLOUDS WILL INCREASE AGAIN THURSDAY AS A WEAK FRONT
APPROACHES AND THERE ARE LIKELY POPS ON THE COAST. THE SNOW LEVEL IN
THE MOUNTAINS WILL FALL TO 3500 FEET TONIGHT AND WEDNESDAY AND
REMAIN THERE THROUGH THURSDAY. BURKE

.LONG TERM...PREVIOUS DISCUSSION...MODELS ARE RATHER CONSISTENT IN
DIGGING A DEEP 515 DAM 500 MB LOW TO AROUND 50N 145W SATURDAY NIGHT
AND SUNDAY AS COLD AIR DUMPING OUT OF THE BERING SEA MOVES SOUTHEAST
INTO THE GULF OF ALASKA. FLOW TO THE SOUTH OF THE SPRAWLING UPPER
LOW TO OUR WEST WILL TAP INTO SOME TROPICAL OR SUBTROPICAL MOISTURE
NEAR HAWAII AND WRAP IT NE INTO OUR AREA THIS WEEKEND. OVER THE
WEEKEND...3 TO 5 INCHES OF RAIN COULD FALL OVER THE OLYMPICS AND
NORTH CASCADES WITH A INCH OR TWO POSSIBLE IN THE LOWLANDS. EXPECT
TEMPERATURES TO MODERATE SOMEWHAT OVER THE WEEKEND...BUT HEIGHTS
REMAIN LOW ENOUGH SO THAT SNOW LEVELS ONLY BRIEFLY RISE TO OVER 6000
FEET. MODEL CONSISTENCY AND CONTINUITY BEYOND SUNDAY IS POOR. NO
MAJOR CHANGES WERE MADE TO THE EXTENDED FORECAST. ALBRECHT

&&

.AVIATION...SOUTHWEST FLOW ALOFT WILL CONTINUE OVER WESTERN
WASHINGTON...WITH A WEAK COLD FRONT MOVING INLAND THIS AFTERNOON AND
ITS UPPER TROUGH MOVING INTO THE AREA TONIGHT. ONSHORE FLOW WILL
INCREASE AND BE STRONG LATE TODAY AND TONIGHT. THE AIR MASS WILL
BECOME MOIST.

MARINE STRATUS COVERS THE COASTAL WATERS...COAST...AND PORTIONS OF
THE WESTERN WASHINGTON INTERIOR LOWLANDS THIS MORNING -- MAINLY IN
THE WEST PART OF THE SOUTH INTERIOR AND THE NORTH INTERIOR. IT
SHOULD GRADUALLY DECREASE DURING THE NEXT FEW HOURS. HOWEVER MID AND
HIGH LEVEL MOISTURE WILL INCREASE WITH THE COLD FRONT...AND LOW
CLOUDS WILL INCREASE TONIGHT. MOST OF THE FORECAST AREA SHOULD HAVE
MVFR TO LOCAL IFR CEILINGS FROM LATE THIS EVENING THROUGH WEDNESDAY
MORNING.

KSEA...SOUTHERLY WIND 4-8 KT...BECOMING NORTHERLY 6-12 KT THIS
AFTERNOON...THEN SOUTHWEST AGAIN THIS EVENING. THE WIND FORECAST AT
KSEA IS HIGHLY UNCERTAIN...BECAUSE IT WILL BE NEAR THE LINE WHERE
NORTHERLIES COMING FROM THE NORTH SOUND MEET WITH THE
SOUTHWESTERLIES COMING THROUGH THE SOUTH SOUND. THERE COULD ALSO BE
PERIODS WHEN KSEA AND KBFI HAVE OPPOSING WINDS.   MCDONNAL

&&

.MARINE...A WEAK COLD FRONT OVER THE OFFSHORE WATERS WILL MOVE
ACROSS WESTERN WASHINGTON THIS AFTERNOON...FOLLOWED BY STRONG
ONSHORE FLOW. SOLID WESTERLY GALES ARE EXPECTED IN THE CENTRAL AND
EASTERN STRAIT OF JUAN DE FUCA THIS AFTERNOON AND TONIGHT...WITH 30
TO 40 KT LIKELY. MARGINAL GALES ARE ALSO LIKELY OVER THE NORTHWEST
PART OF THE COASTAL WATERS...WITH SMALL CRAFT ADVISORY WINDS FOR ALL
OTHER MARINE ZONES.

ONSHORE FLOW WILL EASE WEDNESDAY AND WEDNESDAY NIGHT AS HIGH
PRESSURE MOVES FROM THE COASTAL WATERS INTO WESTERN WASHINGTON.
ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE FORECAST AREA THURSDAY
AND THURSDAY NIGHT...FOLLOWED BY RELATIVELY WEAK ONSHORE FLOW
FRIDAY. A STRONGER FRONTAL SYSTEM WILL REACH THE AREA SATURDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WIND ADVISORY FROM 2 PM TODAY TO 1 AM WEDNESDAY FOR ADMIRALTY
       INLET.
PZ...GALE WARNING THROUGH TONIGHT CENTRAL AND EASTERN STRAIT.
    .GALE WARNING FOR TONIGHT COASTAL WATERS ZONES 150 170 173.
    .SMALL CRAFT ADVISORY ALL OTHER WATERS THROUGH TONIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML





000
FXUS66 KSEW 211522
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
830 AM PDT TUE APR 21 2015

.SYNOPSIS...A COLD FRONT WILL MOVE INLAND THIS AFTERNOON AND EVENING
BRINGING AN ABRUPT CHANGE IN THE WEATHER. COOL AND LOCALLY WINDY
CONDITIONS WITH SHOWERS ARE LIKELY TONIGHT INTO WEDNESDAY. SNOW
LEVELS WILL FALL TONIGHT AND WEDNESDAY IN THE MOUNTAINS. A WEAK
FRONT WILL ARRIVE THURSDAY BRINGING A CHANCE OF RAIN. MOIST
SOUTHWEST FLOW ALOFT WILL BRING PERIODS OF RAIN NEXT WEEKEND.

&&

.SHORT TERM...STRATUS HAS PUSHED INTO THE SOUTHWEST AND THERE ARE
PATCHES NEAR THE STRAIT AS WELL. A FRONT OFFSHORE THIS MORNING WILL
MOVE INLAND THIS AFTERNOON AND EVENING. STRONG ONSHORE FLOW BEHIND
THE FRONT WILL BRING WINDY CONDITIONS TO A FEW ZONES NEAR THE STRAIT
AND A WIND ADVISORY IS IN EFFECT FOR THE ADMIRALTY INLET AREA. POPS
RANGE FROM CHANCE TO LIKELY TONIGHT. A PUGET SOUND CONVERGENCE ZONE
IS LIKELY TO FORM TONIGHT OVER SNOHOMISH AND KING COUNTIES AND IT
WILL LAST INTO WEDNESDAY. HIGHS WILL BE IN THE LOW 60S TODAY THEN
FALL SEVERAL DEGREES TOMORROW.

WEDNESDAY WILL BE CLOUDY UNDER CONTINUED ONSHORE FLOW BUT SOME
CLEARING MAY OCCUR WEDNESDAY NIGHT AS AN UPPER AND SURFACE RIDGE
TEMPORARILY BUILDS. SHOWERS ARE FORECAST TO TAPER CONSIDERABLY
WEDNESDAY NIGHT. CLOUDS WILL INCREASE AGAIN THURSDAY AS A WEAK FRONT
APPROACHES AND THERE ARE LIKELY POPS ON THE COAST. THE SNOW LEVEL IN
THE MOUNTAINS WILL FALL TO 3500 FEET TONIGHT AND WEDNESDAY AND
REMAIN THERE THROUGH THURSDAY. BURKE

.LONG TERM...PREVIOUS DISCUSSION...MODELS ARE RATHER CONSISTENT IN
DIGGING A DEEP 515 DAM 500 MB LOW TO AROUND 50N 145W SATURDAY NIGHT
AND SUNDAY AS COLD AIR DUMPING OUT OF THE BERING SEA MOVES SOUTHEAST
INTO THE GULF OF ALASKA. FLOW TO THE SOUTH OF THE SPRAWLING UPPER
LOW TO OUR WEST WILL TAP INTO SOME TROPICAL OR SUBTROPICAL MOISTURE
NEAR HAWAII AND WRAP IT NE INTO OUR AREA THIS WEEKEND. OVER THE
WEEKEND...3 TO 5 INCHES OF RAIN COULD FALL OVER THE OLYMPICS AND
NORTH CASCADES WITH A INCH OR TWO POSSIBLE IN THE LOWLANDS. EXPECT
TEMPERATURES TO MODERATE SOMEWHAT OVER THE WEEKEND...BUT HEIGHTS
REMAIN LOW ENOUGH SO THAT SNOW LEVELS ONLY BRIEFLY RISE TO OVER 6000
FEET. MODEL CONSISTENCY AND CONTINUITY BEYOND SUNDAY IS POOR. NO
MAJOR CHANGES WERE MADE TO THE EXTENDED FORECAST. ALBRECHT

&&

.AVIATION...SOUTHWEST FLOW ALOFT WILL CONTINUE OVER WESTERN
WASHINGTON...WITH A WEAK COLD FRONT MOVING INLAND THIS AFTERNOON AND
ITS UPPER TROUGH MOVING INTO THE AREA TONIGHT. ONSHORE FLOW WILL
INCREASE AND BE STRONG LATE TODAY AND TONIGHT. THE AIR MASS WILL
BECOME MOIST.

MARINE STRATUS COVERS THE COASTAL WATERS...COAST...AND PORTIONS OF
THE WESTERN WASHINGTON INTERIOR LOWLANDS THIS MORNING -- MAINLY IN
THE WEST PART OF THE SOUTH INTERIOR AND THE NORTH INTERIOR. IT
SHOULD GRADUALLY DECREASE DURING THE NEXT FEW HOURS. HOWEVER MID AND
HIGH LEVEL MOISTURE WILL INCREASE WITH THE COLD FRONT...AND LOW
CLOUDS WILL INCREASE TONIGHT. MOST OF THE FORECAST AREA SHOULD HAVE
MVFR TO LOCAL IFR CEILINGS FROM LATE THIS EVENING THROUGH WEDNESDAY
MORNING.

KSEA...SOUTHERLY WIND 4-8 KT...BECOMING NORTHERLY 6-12 KT THIS
AFTERNOON...THEN SOUTHWEST AGAIN THIS EVENING. THE WIND FORECAST AT
KSEA IS HIGHLY UNCERTAIN...BECAUSE IT WILL BE NEAR THE LINE WHERE
NORTHERLIES COMING FROM THE NORTH SOUND MEET WITH THE
SOUTHWESTERLIES COMING THROUGH THE SOUTH SOUND. THERE COULD ALSO BE
PERIODS WHEN KSEA AND KBFI HAVE OPPOSING WINDS.   MCDONNAL

&&

.MARINE...A WEAK COLD FRONT OVER THE OFFSHORE WATERS WILL MOVE
ACROSS WESTERN WASHINGTON THIS AFTERNOON...FOLLOWED BY STRONG
ONSHORE FLOW. SOLID WESTERLY GALES ARE EXPECTED IN THE CENTRAL AND
EASTERN STRAIT OF JUAN DE FUCA THIS AFTERNOON AND TONIGHT...WITH 30
TO 40 KT LIKELY. MARGINAL GALES ARE ALSO LIKELY OVER THE NORTHWEST
PART OF THE COASTAL WATERS...WITH SMALL CRAFT ADVISORY WINDS FOR ALL
OTHER MARINE ZONES.

ONSHORE FLOW WILL EASE WEDNESDAY AND WEDNESDAY NIGHT AS HIGH
PRESSURE MOVES FROM THE COASTAL WATERS INTO WESTERN WASHINGTON.
ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE FORECAST AREA THURSDAY
AND THURSDAY NIGHT...FOLLOWED BY RELATIVELY WEAK ONSHORE FLOW
FRIDAY. A STRONGER FRONTAL SYSTEM WILL REACH THE AREA SATURDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WIND ADVISORY FROM 2 PM TODAY TO 1 AM WEDNESDAY FOR ADMIRALTY
       INLET.
PZ...GALE WARNING THROUGH TONIGHT CENTRAL AND EASTERN STRAIT.
    .GALE WARNING FOR TONIGHT COASTAL WATERS ZONES 150 170 173.
    .SMALL CRAFT ADVISORY ALL OTHER WATERS THROUGH TONIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML





000
FXUS66 KSEW 211522
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
830 AM PDT TUE APR 21 2015

.SYNOPSIS...A COLD FRONT WILL MOVE INLAND THIS AFTERNOON AND EVENING
BRINGING AN ABRUPT CHANGE IN THE WEATHER. COOL AND LOCALLY WINDY
CONDITIONS WITH SHOWERS ARE LIKELY TONIGHT INTO WEDNESDAY. SNOW
LEVELS WILL FALL TONIGHT AND WEDNESDAY IN THE MOUNTAINS. A WEAK
FRONT WILL ARRIVE THURSDAY BRINGING A CHANCE OF RAIN. MOIST
SOUTHWEST FLOW ALOFT WILL BRING PERIODS OF RAIN NEXT WEEKEND.

&&

.SHORT TERM...STRATUS HAS PUSHED INTO THE SOUTHWEST AND THERE ARE
PATCHES NEAR THE STRAIT AS WELL. A FRONT OFFSHORE THIS MORNING WILL
MOVE INLAND THIS AFTERNOON AND EVENING. STRONG ONSHORE FLOW BEHIND
THE FRONT WILL BRING WINDY CONDITIONS TO A FEW ZONES NEAR THE STRAIT
AND A WIND ADVISORY IS IN EFFECT FOR THE ADMIRALTY INLET AREA. POPS
RANGE FROM CHANCE TO LIKELY TONIGHT. A PUGET SOUND CONVERGENCE ZONE
IS LIKELY TO FORM TONIGHT OVER SNOHOMISH AND KING COUNTIES AND IT
WILL LAST INTO WEDNESDAY. HIGHS WILL BE IN THE LOW 60S TODAY THEN
FALL SEVERAL DEGREES TOMORROW.

WEDNESDAY WILL BE CLOUDY UNDER CONTINUED ONSHORE FLOW BUT SOME
CLEARING MAY OCCUR WEDNESDAY NIGHT AS AN UPPER AND SURFACE RIDGE
TEMPORARILY BUILDS. SHOWERS ARE FORECAST TO TAPER CONSIDERABLY
WEDNESDAY NIGHT. CLOUDS WILL INCREASE AGAIN THURSDAY AS A WEAK FRONT
APPROACHES AND THERE ARE LIKELY POPS ON THE COAST. THE SNOW LEVEL IN
THE MOUNTAINS WILL FALL TO 3500 FEET TONIGHT AND WEDNESDAY AND
REMAIN THERE THROUGH THURSDAY. BURKE

.LONG TERM...PREVIOUS DISCUSSION...MODELS ARE RATHER CONSISTENT IN
DIGGING A DEEP 515 DAM 500 MB LOW TO AROUND 50N 145W SATURDAY NIGHT
AND SUNDAY AS COLD AIR DUMPING OUT OF THE BERING SEA MOVES SOUTHEAST
INTO THE GULF OF ALASKA. FLOW TO THE SOUTH OF THE SPRAWLING UPPER
LOW TO OUR WEST WILL TAP INTO SOME TROPICAL OR SUBTROPICAL MOISTURE
NEAR HAWAII AND WRAP IT NE INTO OUR AREA THIS WEEKEND. OVER THE
WEEKEND...3 TO 5 INCHES OF RAIN COULD FALL OVER THE OLYMPICS AND
NORTH CASCADES WITH A INCH OR TWO POSSIBLE IN THE LOWLANDS. EXPECT
TEMPERATURES TO MODERATE SOMEWHAT OVER THE WEEKEND...BUT HEIGHTS
REMAIN LOW ENOUGH SO THAT SNOW LEVELS ONLY BRIEFLY RISE TO OVER 6000
FEET. MODEL CONSISTENCY AND CONTINUITY BEYOND SUNDAY IS POOR. NO
MAJOR CHANGES WERE MADE TO THE EXTENDED FORECAST. ALBRECHT

&&

.AVIATION...SOUTHWEST FLOW ALOFT WILL CONTINUE OVER WESTERN
WASHINGTON...WITH A WEAK COLD FRONT MOVING INLAND THIS AFTERNOON AND
ITS UPPER TROUGH MOVING INTO THE AREA TONIGHT. ONSHORE FLOW WILL
INCREASE AND BE STRONG LATE TODAY AND TONIGHT. THE AIR MASS WILL
BECOME MOIST.

MARINE STRATUS COVERS THE COASTAL WATERS...COAST...AND PORTIONS OF
THE WESTERN WASHINGTON INTERIOR LOWLANDS THIS MORNING -- MAINLY IN
THE WEST PART OF THE SOUTH INTERIOR AND THE NORTH INTERIOR. IT
SHOULD GRADUALLY DECREASE DURING THE NEXT FEW HOURS. HOWEVER MID AND
HIGH LEVEL MOISTURE WILL INCREASE WITH THE COLD FRONT...AND LOW
CLOUDS WILL INCREASE TONIGHT. MOST OF THE FORECAST AREA SHOULD HAVE
MVFR TO LOCAL IFR CEILINGS FROM LATE THIS EVENING THROUGH WEDNESDAY
MORNING.

KSEA...SOUTHERLY WIND 4-8 KT...BECOMING NORTHERLY 6-12 KT THIS
AFTERNOON...THEN SOUTHWEST AGAIN THIS EVENING. THE WIND FORECAST AT
KSEA IS HIGHLY UNCERTAIN...BECAUSE IT WILL BE NEAR THE LINE WHERE
NORTHERLIES COMING FROM THE NORTH SOUND MEET WITH THE
SOUTHWESTERLIES COMING THROUGH THE SOUTH SOUND. THERE COULD ALSO BE
PERIODS WHEN KSEA AND KBFI HAVE OPPOSING WINDS.   MCDONNAL

&&

.MARINE...A WEAK COLD FRONT OVER THE OFFSHORE WATERS WILL MOVE
ACROSS WESTERN WASHINGTON THIS AFTERNOON...FOLLOWED BY STRONG
ONSHORE FLOW. SOLID WESTERLY GALES ARE EXPECTED IN THE CENTRAL AND
EASTERN STRAIT OF JUAN DE FUCA THIS AFTERNOON AND TONIGHT...WITH 30
TO 40 KT LIKELY. MARGINAL GALES ARE ALSO LIKELY OVER THE NORTHWEST
PART OF THE COASTAL WATERS...WITH SMALL CRAFT ADVISORY WINDS FOR ALL
OTHER MARINE ZONES.

ONSHORE FLOW WILL EASE WEDNESDAY AND WEDNESDAY NIGHT AS HIGH
PRESSURE MOVES FROM THE COASTAL WATERS INTO WESTERN WASHINGTON.
ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE FORECAST AREA THURSDAY
AND THURSDAY NIGHT...FOLLOWED BY RELATIVELY WEAK ONSHORE FLOW
FRIDAY. A STRONGER FRONTAL SYSTEM WILL REACH THE AREA SATURDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WIND ADVISORY FROM 2 PM TODAY TO 1 AM WEDNESDAY FOR ADMIRALTY
       INLET.
PZ...GALE WARNING THROUGH TONIGHT CENTRAL AND EASTERN STRAIT.
    .GALE WARNING FOR TONIGHT COASTAL WATERS ZONES 150 170 173.
    .SMALL CRAFT ADVISORY ALL OTHER WATERS THROUGH TONIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML





000
FXUS66 KSEW 211522
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
830 AM PDT TUE APR 21 2015

.SYNOPSIS...A COLD FRONT WILL MOVE INLAND THIS AFTERNOON AND EVENING
BRINGING AN ABRUPT CHANGE IN THE WEATHER. COOL AND LOCALLY WINDY
CONDITIONS WITH SHOWERS ARE LIKELY TONIGHT INTO WEDNESDAY. SNOW
LEVELS WILL FALL TONIGHT AND WEDNESDAY IN THE MOUNTAINS. A WEAK
FRONT WILL ARRIVE THURSDAY BRINGING A CHANCE OF RAIN. MOIST
SOUTHWEST FLOW ALOFT WILL BRING PERIODS OF RAIN NEXT WEEKEND.

&&

.SHORT TERM...STRATUS HAS PUSHED INTO THE SOUTHWEST AND THERE ARE
PATCHES NEAR THE STRAIT AS WELL. A FRONT OFFSHORE THIS MORNING WILL
MOVE INLAND THIS AFTERNOON AND EVENING. STRONG ONSHORE FLOW BEHIND
THE FRONT WILL BRING WINDY CONDITIONS TO A FEW ZONES NEAR THE STRAIT
AND A WIND ADVISORY IS IN EFFECT FOR THE ADMIRALTY INLET AREA. POPS
RANGE FROM CHANCE TO LIKELY TONIGHT. A PUGET SOUND CONVERGENCE ZONE
IS LIKELY TO FORM TONIGHT OVER SNOHOMISH AND KING COUNTIES AND IT
WILL LAST INTO WEDNESDAY. HIGHS WILL BE IN THE LOW 60S TODAY THEN
FALL SEVERAL DEGREES TOMORROW.

WEDNESDAY WILL BE CLOUDY UNDER CONTINUED ONSHORE FLOW BUT SOME
CLEARING MAY OCCUR WEDNESDAY NIGHT AS AN UPPER AND SURFACE RIDGE
TEMPORARILY BUILDS. SHOWERS ARE FORECAST TO TAPER CONSIDERABLY
WEDNESDAY NIGHT. CLOUDS WILL INCREASE AGAIN THURSDAY AS A WEAK FRONT
APPROACHES AND THERE ARE LIKELY POPS ON THE COAST. THE SNOW LEVEL IN
THE MOUNTAINS WILL FALL TO 3500 FEET TONIGHT AND WEDNESDAY AND
REMAIN THERE THROUGH THURSDAY. BURKE

.LONG TERM...PREVIOUS DISCUSSION...MODELS ARE RATHER CONSISTENT IN
DIGGING A DEEP 515 DAM 500 MB LOW TO AROUND 50N 145W SATURDAY NIGHT
AND SUNDAY AS COLD AIR DUMPING OUT OF THE BERING SEA MOVES SOUTHEAST
INTO THE GULF OF ALASKA. FLOW TO THE SOUTH OF THE SPRAWLING UPPER
LOW TO OUR WEST WILL TAP INTO SOME TROPICAL OR SUBTROPICAL MOISTURE
NEAR HAWAII AND WRAP IT NE INTO OUR AREA THIS WEEKEND. OVER THE
WEEKEND...3 TO 5 INCHES OF RAIN COULD FALL OVER THE OLYMPICS AND
NORTH CASCADES WITH A INCH OR TWO POSSIBLE IN THE LOWLANDS. EXPECT
TEMPERATURES TO MODERATE SOMEWHAT OVER THE WEEKEND...BUT HEIGHTS
REMAIN LOW ENOUGH SO THAT SNOW LEVELS ONLY BRIEFLY RISE TO OVER 6000
FEET. MODEL CONSISTENCY AND CONTINUITY BEYOND SUNDAY IS POOR. NO
MAJOR CHANGES WERE MADE TO THE EXTENDED FORECAST. ALBRECHT

&&

.AVIATION...SOUTHWEST FLOW ALOFT WILL CONTINUE OVER WESTERN
WASHINGTON...WITH A WEAK COLD FRONT MOVING INLAND THIS AFTERNOON AND
ITS UPPER TROUGH MOVING INTO THE AREA TONIGHT. ONSHORE FLOW WILL
INCREASE AND BE STRONG LATE TODAY AND TONIGHT. THE AIR MASS WILL
BECOME MOIST.

MARINE STRATUS COVERS THE COASTAL WATERS...COAST...AND PORTIONS OF
THE WESTERN WASHINGTON INTERIOR LOWLANDS THIS MORNING -- MAINLY IN
THE WEST PART OF THE SOUTH INTERIOR AND THE NORTH INTERIOR. IT
SHOULD GRADUALLY DECREASE DURING THE NEXT FEW HOURS. HOWEVER MID AND
HIGH LEVEL MOISTURE WILL INCREASE WITH THE COLD FRONT...AND LOW
CLOUDS WILL INCREASE TONIGHT. MOST OF THE FORECAST AREA SHOULD HAVE
MVFR TO LOCAL IFR CEILINGS FROM LATE THIS EVENING THROUGH WEDNESDAY
MORNING.

KSEA...SOUTHERLY WIND 4-8 KT...BECOMING NORTHERLY 6-12 KT THIS
AFTERNOON...THEN SOUTHWEST AGAIN THIS EVENING. THE WIND FORECAST AT
KSEA IS HIGHLY UNCERTAIN...BECAUSE IT WILL BE NEAR THE LINE WHERE
NORTHERLIES COMING FROM THE NORTH SOUND MEET WITH THE
SOUTHWESTERLIES COMING THROUGH THE SOUTH SOUND. THERE COULD ALSO BE
PERIODS WHEN KSEA AND KBFI HAVE OPPOSING WINDS.   MCDONNAL

&&

.MARINE...A WEAK COLD FRONT OVER THE OFFSHORE WATERS WILL MOVE
ACROSS WESTERN WASHINGTON THIS AFTERNOON...FOLLOWED BY STRONG
ONSHORE FLOW. SOLID WESTERLY GALES ARE EXPECTED IN THE CENTRAL AND
EASTERN STRAIT OF JUAN DE FUCA THIS AFTERNOON AND TONIGHT...WITH 30
TO 40 KT LIKELY. MARGINAL GALES ARE ALSO LIKELY OVER THE NORTHWEST
PART OF THE COASTAL WATERS...WITH SMALL CRAFT ADVISORY WINDS FOR ALL
OTHER MARINE ZONES.

ONSHORE FLOW WILL EASE WEDNESDAY AND WEDNESDAY NIGHT AS HIGH
PRESSURE MOVES FROM THE COASTAL WATERS INTO WESTERN WASHINGTON.
ANOTHER WEAK COLD FRONT WILL MOVE ACROSS THE FORECAST AREA THURSDAY
AND THURSDAY NIGHT...FOLLOWED BY RELATIVELY WEAK ONSHORE FLOW
FRIDAY. A STRONGER FRONTAL SYSTEM WILL REACH THE AREA SATURDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WIND ADVISORY FROM 2 PM TODAY TO 1 AM WEDNESDAY FOR ADMIRALTY
       INLET.
PZ...GALE WARNING THROUGH TONIGHT CENTRAL AND EASTERN STRAIT.
    .GALE WARNING FOR TONIGHT COASTAL WATERS ZONES 150 170 173.
    .SMALL CRAFT ADVISORY ALL OTHER WATERS THROUGH TONIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML





000
FXUS66 KOTX 211131
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
431 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
Today through Wednesday...The ridge axis, located over central
Washington as of 2 am, will be nudged east today as an upper
trough swings toward the coast today. The trough will pass
through the region tonight into Wednesday, bringing a chance of
showers to portions of the forecast area. Models are now trending
toward the GFS solution of a closed low tracking across the
forecast area, leaving the ECMWF as the outlier with an open wave
clipping the northern zones. PoPs have been trended toward the
consensus but this will not be a slam dunk for showers across
central WA. Moisture should reach the Cascade crest late this
afternoon or early this evening and afternoon instability may be
enough to produce a thunderstorm or two. The cold front weakens as
it crosses the Cascades and encounters dry air while westerly flow
acts to rain shadow the east slopes and basin. There does appear
to be a reinforcing shot of moisture moving up from the south that
will bring a chance of showers to the NE Blue Mts overnight. The
best chance for showers will be on Wednesday as the trough
dynamics interact with upslope flow for the rising terrain east of
the basin. There will also be a chance of thunderstorms for the
Idaho panhandle as the cold pool aloft destabilizes the
atmosphere.

The breakdown of the ridge will also result in gusty winds for
the Cascade valleys starting this afternoon as the cooler more
dense marine air invades the gap valleys. Gusty winds will spread
to the Waterville Plateau this evening and continue overnight. The
eastern basin and Palouse will see breezy conditions with the
frontal passage Wednesday. Generally expect sustained winds of 15
to 25 mph with gusts of 30 to 40 mph. Relative humidity should be
recovering by the time the winds increase since it looks like the
marine layer will be deep enough for some of the moisture to make
it over the Cascades.

Temperatures will continue the warming trend today then cool
significantly for Wednesday with the trough passage when most
valley locations will be in the upper 50s to mid 60s. /Kelch

Wednesday night through Friday the forecast will follow a blend of
the ECMWF/Canadian/NAM. A very wrapped up closed low will track
northeast across the north Idaho Panhandle and points further
north and east. Meanwhile another deep closed system will drop
south along the B.C. Coast Thursday, then fill as the low moves
along the Canadian border. This low will tap into slightly deeper
Pacific moisture. The cold core Wednesday evening associated with
the closed low will increase lapse rates and destabilize the lower
levels. This will result in some active showers across the
northeast zones Wednesday evening. Surfaces based cape is present
but not overly deep, but there may be enough instability to
support a few lightning strikes through the evening hours.
Thunderstorms were already in the forecast, but were trimmed back
to mainly boundary county up near the Canadian border. Showers
will remain in the forecast with the secondary low, mainly across
the north Idaho Panhandle, and stretching as far west as the
Northeast WA mountains up near the Canadian border. A second area
of showers will be along the Cascade crest. Temperatures will cool
off into the mid 50s to mid 60s, which are very close to seasonal
averages.

Friday night and Saturday the region will be in between weather
systems with weak and short lived high pressure tracking across
the region. Some light orographic mountain showers will be
possible for the Panhandle mountains and across the Cascades,
otherwise expect a period of dry but continued cool weather.

Saturday night through Tuesday a much deeper upper level low will
move into the eastern Pacific and stall. At this time it appears
as if the low may not move inland until mid-week if not later, but
there is much uncertainty in the model solutions through this
period. What we do know is the southwesterly flow will tap into a
very deep tropical atmospheric river Saturday night that looks
like it will linger through at least Tuesday. PWATS go up to
around an inch which is well above normal. A deep southwest
moisture tap of this magnitude will not need much in the way of a
lifting process to wring out any and all moisture across the
region. It looks like we will be in for an extended period of
moderate stratiform precipitation Sunday through Tuesday.
Southwest flow will warm temperatures, but these will likely be
inhibited somewhat by cloud cover and widespread rain and not
reach potential. South-southwest winds will become breezy Saturday
night and Sunday and remain elevated at least through Monday.
Tobin.

&&

.AVIATION...
12Z TAFS: High pressure will result in VFR conditions through 12Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. Gusty southwest winds will develop after 06Z Wednesday
in the KGEG/KSFF/KPUW areas. /EK


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 211131
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
431 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
Today through Wednesday...The ridge axis, located over central
Washington as of 2 am, will be nudged east today as an upper
trough swings toward the coast today. The trough will pass
through the region tonight into Wednesday, bringing a chance of
showers to portions of the forecast area. Models are now trending
toward the GFS solution of a closed low tracking across the
forecast area, leaving the ECMWF as the outlier with an open wave
clipping the northern zones. PoPs have been trended toward the
consensus but this will not be a slam dunk for showers across
central WA. Moisture should reach the Cascade crest late this
afternoon or early this evening and afternoon instability may be
enough to produce a thunderstorm or two. The cold front weakens as
it crosses the Cascades and encounters dry air while westerly flow
acts to rain shadow the east slopes and basin. There does appear
to be a reinforcing shot of moisture moving up from the south that
will bring a chance of showers to the NE Blue Mts overnight. The
best chance for showers will be on Wednesday as the trough
dynamics interact with upslope flow for the rising terrain east of
the basin. There will also be a chance of thunderstorms for the
Idaho panhandle as the cold pool aloft destabilizes the
atmosphere.

The breakdown of the ridge will also result in gusty winds for
the Cascade valleys starting this afternoon as the cooler more
dense marine air invades the gap valleys. Gusty winds will spread
to the Waterville Plateau this evening and continue overnight. The
eastern basin and Palouse will see breezy conditions with the
frontal passage Wednesday. Generally expect sustained winds of 15
to 25 mph with gusts of 30 to 40 mph. Relative humidity should be
recovering by the time the winds increase since it looks like the
marine layer will be deep enough for some of the moisture to make
it over the Cascades.

Temperatures will continue the warming trend today then cool
significantly for Wednesday with the trough passage when most
valley locations will be in the upper 50s to mid 60s. /Kelch

Wednesday night through Friday the forecast will follow a blend of
the ECMWF/Canadian/NAM. A very wrapped up closed low will track
northeast across the north Idaho Panhandle and points further
north and east. Meanwhile another deep closed system will drop
south along the B.C. Coast Thursday, then fill as the low moves
along the Canadian border. This low will tap into slightly deeper
Pacific moisture. The cold core Wednesday evening associated with
the closed low will increase lapse rates and destabilize the lower
levels. This will result in some active showers across the
northeast zones Wednesday evening. Surfaces based cape is present
but not overly deep, but there may be enough instability to
support a few lightning strikes through the evening hours.
Thunderstorms were already in the forecast, but were trimmed back
to mainly boundary county up near the Canadian border. Showers
will remain in the forecast with the secondary low, mainly across
the north Idaho Panhandle, and stretching as far west as the
Northeast WA mountains up near the Canadian border. A second area
of showers will be along the Cascade crest. Temperatures will cool
off into the mid 50s to mid 60s, which are very close to seasonal
averages.

Friday night and Saturday the region will be in between weather
systems with weak and short lived high pressure tracking across
the region. Some light orographic mountain showers will be
possible for the Panhandle mountains and across the Cascades,
otherwise expect a period of dry but continued cool weather.

Saturday night through Tuesday a much deeper upper level low will
move into the eastern Pacific and stall. At this time it appears
as if the low may not move inland until mid-week if not later, but
there is much uncertainty in the model solutions through this
period. What we do know is the southwesterly flow will tap into a
very deep tropical atmospheric river Saturday night that looks
like it will linger through at least Tuesday. PWATS go up to
around an inch which is well above normal. A deep southwest
moisture tap of this magnitude will not need much in the way of a
lifting process to wring out any and all moisture across the
region. It looks like we will be in for an extended period of
moderate stratiform precipitation Sunday through Tuesday.
Southwest flow will warm temperatures, but these will likely be
inhibited somewhat by cloud cover and widespread rain and not
reach potential. South-southwest winds will become breezy Saturday
night and Sunday and remain elevated at least through Monday.
Tobin.

&&

.AVIATION...
12Z TAFS: High pressure will result in VFR conditions through 12Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. Gusty southwest winds will develop after 06Z Wednesday
in the KGEG/KSFF/KPUW areas. /EK


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 211131
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
431 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
Today through Wednesday...The ridge axis, located over central
Washington as of 2 am, will be nudged east today as an upper
trough swings toward the coast today. The trough will pass
through the region tonight into Wednesday, bringing a chance of
showers to portions of the forecast area. Models are now trending
toward the GFS solution of a closed low tracking across the
forecast area, leaving the ECMWF as the outlier with an open wave
clipping the northern zones. PoPs have been trended toward the
consensus but this will not be a slam dunk for showers across
central WA. Moisture should reach the Cascade crest late this
afternoon or early this evening and afternoon instability may be
enough to produce a thunderstorm or two. The cold front weakens as
it crosses the Cascades and encounters dry air while westerly flow
acts to rain shadow the east slopes and basin. There does appear
to be a reinforcing shot of moisture moving up from the south that
will bring a chance of showers to the NE Blue Mts overnight. The
best chance for showers will be on Wednesday as the trough
dynamics interact with upslope flow for the rising terrain east of
the basin. There will also be a chance of thunderstorms for the
Idaho panhandle as the cold pool aloft destabilizes the
atmosphere.

The breakdown of the ridge will also result in gusty winds for
the Cascade valleys starting this afternoon as the cooler more
dense marine air invades the gap valleys. Gusty winds will spread
to the Waterville Plateau this evening and continue overnight. The
eastern basin and Palouse will see breezy conditions with the
frontal passage Wednesday. Generally expect sustained winds of 15
to 25 mph with gusts of 30 to 40 mph. Relative humidity should be
recovering by the time the winds increase since it looks like the
marine layer will be deep enough for some of the moisture to make
it over the Cascades.

Temperatures will continue the warming trend today then cool
significantly for Wednesday with the trough passage when most
valley locations will be in the upper 50s to mid 60s. /Kelch

Wednesday night through Friday the forecast will follow a blend of
the ECMWF/Canadian/NAM. A very wrapped up closed low will track
northeast across the north Idaho Panhandle and points further
north and east. Meanwhile another deep closed system will drop
south along the B.C. Coast Thursday, then fill as the low moves
along the Canadian border. This low will tap into slightly deeper
Pacific moisture. The cold core Wednesday evening associated with
the closed low will increase lapse rates and destabilize the lower
levels. This will result in some active showers across the
northeast zones Wednesday evening. Surfaces based cape is present
but not overly deep, but there may be enough instability to
support a few lightning strikes through the evening hours.
Thunderstorms were already in the forecast, but were trimmed back
to mainly boundary county up near the Canadian border. Showers
will remain in the forecast with the secondary low, mainly across
the north Idaho Panhandle, and stretching as far west as the
Northeast WA mountains up near the Canadian border. A second area
of showers will be along the Cascade crest. Temperatures will cool
off into the mid 50s to mid 60s, which are very close to seasonal
averages.

Friday night and Saturday the region will be in between weather
systems with weak and short lived high pressure tracking across
the region. Some light orographic mountain showers will be
possible for the Panhandle mountains and across the Cascades,
otherwise expect a period of dry but continued cool weather.

Saturday night through Tuesday a much deeper upper level low will
move into the eastern Pacific and stall. At this time it appears
as if the low may not move inland until mid-week if not later, but
there is much uncertainty in the model solutions through this
period. What we do know is the southwesterly flow will tap into a
very deep tropical atmospheric river Saturday night that looks
like it will linger through at least Tuesday. PWATS go up to
around an inch which is well above normal. A deep southwest
moisture tap of this magnitude will not need much in the way of a
lifting process to wring out any and all moisture across the
region. It looks like we will be in for an extended period of
moderate stratiform precipitation Sunday through Tuesday.
Southwest flow will warm temperatures, but these will likely be
inhibited somewhat by cloud cover and widespread rain and not
reach potential. South-southwest winds will become breezy Saturday
night and Sunday and remain elevated at least through Monday.
Tobin.

&&

.AVIATION...
12Z TAFS: High pressure will result in VFR conditions through 12Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. Gusty southwest winds will develop after 06Z Wednesday
in the KGEG/KSFF/KPUW areas. /EK


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 211131
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
431 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
Today through Wednesday...The ridge axis, located over central
Washington as of 2 am, will be nudged east today as an upper
trough swings toward the coast today. The trough will pass
through the region tonight into Wednesday, bringing a chance of
showers to portions of the forecast area. Models are now trending
toward the GFS solution of a closed low tracking across the
forecast area, leaving the ECMWF as the outlier with an open wave
clipping the northern zones. PoPs have been trended toward the
consensus but this will not be a slam dunk for showers across
central WA. Moisture should reach the Cascade crest late this
afternoon or early this evening and afternoon instability may be
enough to produce a thunderstorm or two. The cold front weakens as
it crosses the Cascades and encounters dry air while westerly flow
acts to rain shadow the east slopes and basin. There does appear
to be a reinforcing shot of moisture moving up from the south that
will bring a chance of showers to the NE Blue Mts overnight. The
best chance for showers will be on Wednesday as the trough
dynamics interact with upslope flow for the rising terrain east of
the basin. There will also be a chance of thunderstorms for the
Idaho panhandle as the cold pool aloft destabilizes the
atmosphere.

The breakdown of the ridge will also result in gusty winds for
the Cascade valleys starting this afternoon as the cooler more
dense marine air invades the gap valleys. Gusty winds will spread
to the Waterville Plateau this evening and continue overnight. The
eastern basin and Palouse will see breezy conditions with the
frontal passage Wednesday. Generally expect sustained winds of 15
to 25 mph with gusts of 30 to 40 mph. Relative humidity should be
recovering by the time the winds increase since it looks like the
marine layer will be deep enough for some of the moisture to make
it over the Cascades.

Temperatures will continue the warming trend today then cool
significantly for Wednesday with the trough passage when most
valley locations will be in the upper 50s to mid 60s. /Kelch

Wednesday night through Friday the forecast will follow a blend of
the ECMWF/Canadian/NAM. A very wrapped up closed low will track
northeast across the north Idaho Panhandle and points further
north and east. Meanwhile another deep closed system will drop
south along the B.C. Coast Thursday, then fill as the low moves
along the Canadian border. This low will tap into slightly deeper
Pacific moisture. The cold core Wednesday evening associated with
the closed low will increase lapse rates and destabilize the lower
levels. This will result in some active showers across the
northeast zones Wednesday evening. Surfaces based cape is present
but not overly deep, but there may be enough instability to
support a few lightning strikes through the evening hours.
Thunderstorms were already in the forecast, but were trimmed back
to mainly boundary county up near the Canadian border. Showers
will remain in the forecast with the secondary low, mainly across
the north Idaho Panhandle, and stretching as far west as the
Northeast WA mountains up near the Canadian border. A second area
of showers will be along the Cascade crest. Temperatures will cool
off into the mid 50s to mid 60s, which are very close to seasonal
averages.

Friday night and Saturday the region will be in between weather
systems with weak and short lived high pressure tracking across
the region. Some light orographic mountain showers will be
possible for the Panhandle mountains and across the Cascades,
otherwise expect a period of dry but continued cool weather.

Saturday night through Tuesday a much deeper upper level low will
move into the eastern Pacific and stall. At this time it appears
as if the low may not move inland until mid-week if not later, but
there is much uncertainty in the model solutions through this
period. What we do know is the southwesterly flow will tap into a
very deep tropical atmospheric river Saturday night that looks
like it will linger through at least Tuesday. PWATS go up to
around an inch which is well above normal. A deep southwest
moisture tap of this magnitude will not need much in the way of a
lifting process to wring out any and all moisture across the
region. It looks like we will be in for an extended period of
moderate stratiform precipitation Sunday through Tuesday.
Southwest flow will warm temperatures, but these will likely be
inhibited somewhat by cloud cover and widespread rain and not
reach potential. South-southwest winds will become breezy Saturday
night and Sunday and remain elevated at least through Monday.
Tobin.

&&

.AVIATION...
12Z TAFS: High pressure will result in VFR conditions through 12Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. Gusty southwest winds will develop after 06Z Wednesday
in the KGEG/KSFF/KPUW areas. /EK


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 211131
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
431 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
Today through Wednesday...The ridge axis, located over central
Washington as of 2 am, will be nudged east today as an upper
trough swings toward the coast today. The trough will pass
through the region tonight into Wednesday, bringing a chance of
showers to portions of the forecast area. Models are now trending
toward the GFS solution of a closed low tracking across the
forecast area, leaving the ECMWF as the outlier with an open wave
clipping the northern zones. PoPs have been trended toward the
consensus but this will not be a slam dunk for showers across
central WA. Moisture should reach the Cascade crest late this
afternoon or early this evening and afternoon instability may be
enough to produce a thunderstorm or two. The cold front weakens as
it crosses the Cascades and encounters dry air while westerly flow
acts to rain shadow the east slopes and basin. There does appear
to be a reinforcing shot of moisture moving up from the south that
will bring a chance of showers to the NE Blue Mts overnight. The
best chance for showers will be on Wednesday as the trough
dynamics interact with upslope flow for the rising terrain east of
the basin. There will also be a chance of thunderstorms for the
Idaho panhandle as the cold pool aloft destabilizes the
atmosphere.

The breakdown of the ridge will also result in gusty winds for
the Cascade valleys starting this afternoon as the cooler more
dense marine air invades the gap valleys. Gusty winds will spread
to the Waterville Plateau this evening and continue overnight. The
eastern basin and Palouse will see breezy conditions with the
frontal passage Wednesday. Generally expect sustained winds of 15
to 25 mph with gusts of 30 to 40 mph. Relative humidity should be
recovering by the time the winds increase since it looks like the
marine layer will be deep enough for some of the moisture to make
it over the Cascades.

Temperatures will continue the warming trend today then cool
significantly for Wednesday with the trough passage when most
valley locations will be in the upper 50s to mid 60s. /Kelch

Wednesday night through Friday the forecast will follow a blend of
the ECMWF/Canadian/NAM. A very wrapped up closed low will track
northeast across the north Idaho Panhandle and points further
north and east. Meanwhile another deep closed system will drop
south along the B.C. Coast Thursday, then fill as the low moves
along the Canadian border. This low will tap into slightly deeper
Pacific moisture. The cold core Wednesday evening associated with
the closed low will increase lapse rates and destabilize the lower
levels. This will result in some active showers across the
northeast zones Wednesday evening. Surfaces based cape is present
but not overly deep, but there may be enough instability to
support a few lightning strikes through the evening hours.
Thunderstorms were already in the forecast, but were trimmed back
to mainly boundary county up near the Canadian border. Showers
will remain in the forecast with the secondary low, mainly across
the north Idaho Panhandle, and stretching as far west as the
Northeast WA mountains up near the Canadian border. A second area
of showers will be along the Cascade crest. Temperatures will cool
off into the mid 50s to mid 60s, which are very close to seasonal
averages.

Friday night and Saturday the region will be in between weather
systems with weak and short lived high pressure tracking across
the region. Some light orographic mountain showers will be
possible for the Panhandle mountains and across the Cascades,
otherwise expect a period of dry but continued cool weather.

Saturday night through Tuesday a much deeper upper level low will
move into the eastern Pacific and stall. At this time it appears
as if the low may not move inland until mid-week if not later, but
there is much uncertainty in the model solutions through this
period. What we do know is the southwesterly flow will tap into a
very deep tropical atmospheric river Saturday night that looks
like it will linger through at least Tuesday. PWATS go up to
around an inch which is well above normal. A deep southwest
moisture tap of this magnitude will not need much in the way of a
lifting process to wring out any and all moisture across the
region. It looks like we will be in for an extended period of
moderate stratiform precipitation Sunday through Tuesday.
Southwest flow will warm temperatures, but these will likely be
inhibited somewhat by cloud cover and widespread rain and not
reach potential. South-southwest winds will become breezy Saturday
night and Sunday and remain elevated at least through Monday.
Tobin.

&&

.AVIATION...
12Z TAFS: High pressure will result in VFR conditions through 12Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. Gusty southwest winds will develop after 06Z Wednesday
in the KGEG/KSFF/KPUW areas. /EK


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 211131
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
431 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
Today through Wednesday...The ridge axis, located over central
Washington as of 2 am, will be nudged east today as an upper
trough swings toward the coast today. The trough will pass
through the region tonight into Wednesday, bringing a chance of
showers to portions of the forecast area. Models are now trending
toward the GFS solution of a closed low tracking across the
forecast area, leaving the ECMWF as the outlier with an open wave
clipping the northern zones. PoPs have been trended toward the
consensus but this will not be a slam dunk for showers across
central WA. Moisture should reach the Cascade crest late this
afternoon or early this evening and afternoon instability may be
enough to produce a thunderstorm or two. The cold front weakens as
it crosses the Cascades and encounters dry air while westerly flow
acts to rain shadow the east slopes and basin. There does appear
to be a reinforcing shot of moisture moving up from the south that
will bring a chance of showers to the NE Blue Mts overnight. The
best chance for showers will be on Wednesday as the trough
dynamics interact with upslope flow for the rising terrain east of
the basin. There will also be a chance of thunderstorms for the
Idaho panhandle as the cold pool aloft destabilizes the
atmosphere.

The breakdown of the ridge will also result in gusty winds for
the Cascade valleys starting this afternoon as the cooler more
dense marine air invades the gap valleys. Gusty winds will spread
to the Waterville Plateau this evening and continue overnight. The
eastern basin and Palouse will see breezy conditions with the
frontal passage Wednesday. Generally expect sustained winds of 15
to 25 mph with gusts of 30 to 40 mph. Relative humidity should be
recovering by the time the winds increase since it looks like the
marine layer will be deep enough for some of the moisture to make
it over the Cascades.

Temperatures will continue the warming trend today then cool
significantly for Wednesday with the trough passage when most
valley locations will be in the upper 50s to mid 60s. /Kelch

Wednesday night through Friday the forecast will follow a blend of
the ECMWF/Canadian/NAM. A very wrapped up closed low will track
northeast across the north Idaho Panhandle and points further
north and east. Meanwhile another deep closed system will drop
south along the B.C. Coast Thursday, then fill as the low moves
along the Canadian border. This low will tap into slightly deeper
Pacific moisture. The cold core Wednesday evening associated with
the closed low will increase lapse rates and destabilize the lower
levels. This will result in some active showers across the
northeast zones Wednesday evening. Surfaces based cape is present
but not overly deep, but there may be enough instability to
support a few lightning strikes through the evening hours.
Thunderstorms were already in the forecast, but were trimmed back
to mainly boundary county up near the Canadian border. Showers
will remain in the forecast with the secondary low, mainly across
the north Idaho Panhandle, and stretching as far west as the
Northeast WA mountains up near the Canadian border. A second area
of showers will be along the Cascade crest. Temperatures will cool
off into the mid 50s to mid 60s, which are very close to seasonal
averages.

Friday night and Saturday the region will be in between weather
systems with weak and short lived high pressure tracking across
the region. Some light orographic mountain showers will be
possible for the Panhandle mountains and across the Cascades,
otherwise expect a period of dry but continued cool weather.

Saturday night through Tuesday a much deeper upper level low will
move into the eastern Pacific and stall. At this time it appears
as if the low may not move inland until mid-week if not later, but
there is much uncertainty in the model solutions through this
period. What we do know is the southwesterly flow will tap into a
very deep tropical atmospheric river Saturday night that looks
like it will linger through at least Tuesday. PWATS go up to
around an inch which is well above normal. A deep southwest
moisture tap of this magnitude will not need much in the way of a
lifting process to wring out any and all moisture across the
region. It looks like we will be in for an extended period of
moderate stratiform precipitation Sunday through Tuesday.
Southwest flow will warm temperatures, but these will likely be
inhibited somewhat by cloud cover and widespread rain and not
reach potential. South-southwest winds will become breezy Saturday
night and Sunday and remain elevated at least through Monday.
Tobin.

&&

.AVIATION...
12Z TAFS: High pressure will result in VFR conditions through 12Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. Gusty southwest winds will develop after 06Z Wednesday
in the KGEG/KSFF/KPUW areas. /EK


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KSEW 211049
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
345 AM PDT TUE APR 21 2015

.SYNOPSIS...A STRONG COLD FRONT OVER THE COASTAL WATERS THIS MORNING
WILL SWEEP INLAND THIS AFTERNOON AND THIS EVENING BRINGING AN ABRUPT
CHANGE TO THE WEATHER. COOL AND LOCALLY WINDY CONDITIONS WITH A
CHANCE OF SHOWERS CAN BE EXPECTED TONIGHT INTO WEDNESDAY. SNOW
LEVELS WILL FALL TONIGHT INTO WEDNESDAY IN THE MOUNTAINS. A WEAK
FRONT WILL MOVE ACROSS THE AREA ON THURSDAY BRINGING A CHANCE OF
RAIN. MOIST SOUTHWEST FLOW ALOFT WILL BRING PERIODS OF RAIN NEXT
WEEKEND.

&&

.SHORT TERM...THE UPPER LEVEL RIDGE THAT GAVE SUNNY AND WARM WEATHER
TO WESTERN WASHINGTON OVER THE PAST FEW DAYS HAS MOVED EAST OF THE
CASCADES OVERNIGHT. A MARINE PUSH IS NOW UNDERWAY EARLY THIS MORNING
AS ONSHORE PRESSURE GRADIENTS GRADUALLY RAMP UP. SATELLITE IMAGES
SHOW A RATHER STRONG COLD FRONT SITTING FROM CENTRAL VANCOUVER
ISLAND SSW INTO THE OREGON AND NORTHERN CALIFORNIA OFFSHORE WATERS.
THIS FRONT WILL MOVE INLAND THIS AFTERNOON AND SWEEP EAST OF THE
CASCADES THIS EVENING.

STRATUS AHEAD OF THE INCOMING FRONT HAS MOVED TO THE COASTLINE AND
WILL PUSH INLAND DURING THE MORNING HOURS. BETWEEN 21Z AND 00Z...THE
GFS INCREASES THE KUIL-KBLI PRES GRADIENTS TO AROUND 6 MB. 500 MB
HEIGHTS FALL FROM 560-564 DAM EARLY THIS MORNING TO AROUND 545 DAM
LATE TONIGHT AND THE FREEZING LEVEL WILL FALL TO AROUND 3500 FEET BY
WED MORNING. GIVEN THE STRONG CONVERGENCE OF THE FLOW AROUND THE
OLYMPICS AND UPSLOPE FLOW INTO THE WEST SLOPES OF THE
MOUNTAINS...EXPECT SHOWERS TO BE LIKELY IN THE INTERIOR FROM ABOUT
SEATTLE NORTHWARD AND IN THE MOUNTAINS THIS EVENING. THE CONVERGENCE
ZONE ACTIVITY AND UPSLOPE FLOW WILL KEEP SHOWERS GOING INTO
WEDNESDAY AS THE UPPER LOW DEPARTS TO THE SE OF THE AREA.
TEMPERATURES WILL ONLY TOP OUT IN THE 50S TO AROUND 60 TODAY AND
WILL FALL INTO THE 40S TONIGHT. TEMPERATURES WILL TOP OUT IN THE MID
AND UPPER 50S ON WEDNESDAY...QUITE A BIT COOLER THAN WHAT WE HAVE
BEEN EXPERIENCING IN THE RECENT PAST.

COLD AIR ADVECTION AND WNW FLOW ALOFT WITH AND BEHIND THE FRONT AND
TO THE SOUTH OF A DEVELOPING UPPER LOW OVER VANCOUVER ISLAND THAT
WILL TRACK ESE WILL COMBINE TO GIVE A GOOD GALE TO THE STRAIT OF
JUAN DE FUCA AND W TO NW WINDS 20-35 MPH WITH GUSTS TO 45 MPH TO THE
ADMIRALTY INLET AREA. THE STRONGEST WINDS ARE LIKELY TO OCCUR ON THE
WEST SIDE OF WHIDBEY ISLAND.

A WIND ADVISORY HAS BEEN ISSUED FROM 2 PM THIS AFTERNOON TO 1 AM PDT
WEDNESDAY FOR THE ADMIRALTY INLET AREA. OTHER AREAS AROUND WESTERN
WASHINGTON WILL SEE BREEZY TO LOCALLY WINDY CONDITIONS LATE THIS
AFTERNOON AND EVENING AS WELL. A SPECIAL WEATHER STATEMENT IS ALSO
BEING ISSUED FOR THE MOUNTAINS FOR THE EXPECTATION OF SHARPLY COLDER
WEATHER THERE AND A COUPLE OF INCHES OF SNOW ABOVE ABOUT 3500 FEET.

ANOTHER FRONTAL SYSTEM WILL MOVE ACROSS THE AREA THURSDAY WITH RAIN
LIKELY ON THE COAST AND A CHANCE OF RAIN INLAND. COOL WEATHER WITH A
CHANCE OF SHOWERS IS EXPECTED ON FRIDAY. ALBRECHT

.LONG TERM...MODELS ARE RATHER CONSISTENT IN DIGGING A DEEP 515 DAM
500 MB LOW TO AROUND 50N 145W SATURDAY NIGHT AND SUNDAY AS COLD AIR
DUMPING OUT OF THE BERING SEA MOVES SOUTHEAST INTO THE GULF OF
ALASKA. FLOW TO THE SOUTH OF THE SPRAWLING UPPER LOW TO OUR WEST
WILL TAP INTO SOME TROPICAL OR SUBTROPICAL MOISTURE NEAR HAWAII AND
WRAP IT NE INTO OUR AREA THIS WEEKEND. OVER THE WEEKEND...3 TO 5
INCHES OF RAIN COULD FALL OVER THE OLYMPICS AND NORTH CASCADES WITH
A INCH OR TWO POSSIBLE IN THE LOWLANDS. EXPECT TEMPERATURES TO
MODERATE SOMEWHAT OVER THE WEEKEND...BUT HEIGHTS REMAIN LOW ENOUGH
SO THAT SNOW LEVELS ONLY BRIEFLY RISE TO OVER 6000 FEET. MODEL
CONSISTENCY AND CONTINUITY BEYOND SUNDAY IS POOR. NO MAJOR CHANGES
WERE MADE TO THE EXTENDED FORECAST. ALBRECHT

&&

.AVIATION...WESTERLY FLOW ALOFT WILL BECOME SOUTHWEST THIS MORNING
AS AN UPPER LEVEL TROUGH APPROACHES FROM THE WEST. INCREASING LOW
LEVEL ONSHORE FLOW TODAY WILL HELP THE AIR MASS TO BECOME MOIST AT
LOW LEVELS THIS MORNING. MARINE STRATUS HAS MOVED ONTO THE NORTH
COAST AS OF 06Z...EXPECT IT TO SPREAD ONTO THE CENTRAL
COAST...CHEHALIS GAP AND SOUTH INTERIOR BY DAY BREAK. THE FORECAST
FOR THE CENTRAL SOUND REMAINS A BIT TRICKY WITH THIS PATTERN...THE
EXPECTATION REMAINS FOR LIMITED LOW CLOUDS FORMING AND REMAINING
SHORT LIVED THIS MORNING.

A WEAK COLD FRONT REMAINS ON TRACK TO MOVE THROUGH THE FORECAST AREA
THIS AFTERNOON...FOLLOWED BY AN UPPER LEVEL TROUGH TUESDAY NIGHT.
THIS WILL RESULT IN A SHORT PERIOD OF LIGHT RAIN AND SHOWERS
BEHIND THE FRONT. THE PRIMARY IMPACT WILL BE INCREASING LOW LEVEL
WINDS TODAY.

KSEA...LIGHT NORTH WINDS...BECOMING SOUTHERLY TO 8 KT LATE...THEN
SOUTHWEST 8 TO 12 KT BY THIS AFTERNOON. THIN MARINE STRATUS POSSIBLE
AT THE TERMINAL AROUND 13Z.

&&

.MARINE...STRENGTHENING ONSHORE GRADIENTS THIS MORNING HAVE ALREADY
PRODUCED GALE CONDITIONS IN THE CENTRAL AND EAST STRAIT THIS
MORNING. SMALL CRAFT ADVISORY WINDS REMAIN FORECAST FOR ALL
REMAINING AREA WATERS THROUGH TONIGHT AS A COLD FRONT WORKS THROUGH
THE COASTAL WATERS THIS AFTERNOON AND INLAND DURING THE EVENING.
EXPECT INCREASING NORTHWESTERLY WINDS OVER PARTS OF THE COASTAL
WATERS TO REACH GALE LEVELS BEHIND THE FRONT...WHILE GALE WESTERLIES
REMAIN FORECAST FOR THE CENTRAL AND EASTERN STRAIT TONIGHT. SMALL
CRAFT ADVISORY WINDS WILL CONTINUE FOR ALL OTHER MARINE ZONES
THROUGH MUCH OF TONIGHT.

A SECOND WEAK COLD FRONT WILL CROSS THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT...WITH A STRONGER FRONTAL SYSTEM EXPECTED TO REACH
THE AREA SATURDAY.


&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WIND ADVISORY ADMIRALTY INLET AREA 2 PM THIS AFTERNOON UNTIL 1
AM       PDT WEDNESDAY.
PZ...GALE WARNING THROUGH TONIGHT CENTRAL AND EASTERN STRAIT.
     GALE WARNING FOR TONIGHT COASTAL WATERS ZONES 150 170 173.
     SMALL CRAFT ADVISORY ALL OTHER WATERS THROUGH TONIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML













000
FXUS66 KSEW 211049
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
345 AM PDT TUE APR 21 2015

.SYNOPSIS...A STRONG COLD FRONT OVER THE COASTAL WATERS THIS MORNING
WILL SWEEP INLAND THIS AFTERNOON AND THIS EVENING BRINGING AN ABRUPT
CHANGE TO THE WEATHER. COOL AND LOCALLY WINDY CONDITIONS WITH A
CHANCE OF SHOWERS CAN BE EXPECTED TONIGHT INTO WEDNESDAY. SNOW
LEVELS WILL FALL TONIGHT INTO WEDNESDAY IN THE MOUNTAINS. A WEAK
FRONT WILL MOVE ACROSS THE AREA ON THURSDAY BRINGING A CHANCE OF
RAIN. MOIST SOUTHWEST FLOW ALOFT WILL BRING PERIODS OF RAIN NEXT
WEEKEND.

&&

.SHORT TERM...THE UPPER LEVEL RIDGE THAT GAVE SUNNY AND WARM WEATHER
TO WESTERN WASHINGTON OVER THE PAST FEW DAYS HAS MOVED EAST OF THE
CASCADES OVERNIGHT. A MARINE PUSH IS NOW UNDERWAY EARLY THIS MORNING
AS ONSHORE PRESSURE GRADIENTS GRADUALLY RAMP UP. SATELLITE IMAGES
SHOW A RATHER STRONG COLD FRONT SITTING FROM CENTRAL VANCOUVER
ISLAND SSW INTO THE OREGON AND NORTHERN CALIFORNIA OFFSHORE WATERS.
THIS FRONT WILL MOVE INLAND THIS AFTERNOON AND SWEEP EAST OF THE
CASCADES THIS EVENING.

STRATUS AHEAD OF THE INCOMING FRONT HAS MOVED TO THE COASTLINE AND
WILL PUSH INLAND DURING THE MORNING HOURS. BETWEEN 21Z AND 00Z...THE
GFS INCREASES THE KUIL-KBLI PRES GRADIENTS TO AROUND 6 MB. 500 MB
HEIGHTS FALL FROM 560-564 DAM EARLY THIS MORNING TO AROUND 545 DAM
LATE TONIGHT AND THE FREEZING LEVEL WILL FALL TO AROUND 3500 FEET BY
WED MORNING. GIVEN THE STRONG CONVERGENCE OF THE FLOW AROUND THE
OLYMPICS AND UPSLOPE FLOW INTO THE WEST SLOPES OF THE
MOUNTAINS...EXPECT SHOWERS TO BE LIKELY IN THE INTERIOR FROM ABOUT
SEATTLE NORTHWARD AND IN THE MOUNTAINS THIS EVENING. THE CONVERGENCE
ZONE ACTIVITY AND UPSLOPE FLOW WILL KEEP SHOWERS GOING INTO
WEDNESDAY AS THE UPPER LOW DEPARTS TO THE SE OF THE AREA.
TEMPERATURES WILL ONLY TOP OUT IN THE 50S TO AROUND 60 TODAY AND
WILL FALL INTO THE 40S TONIGHT. TEMPERATURES WILL TOP OUT IN THE MID
AND UPPER 50S ON WEDNESDAY...QUITE A BIT COOLER THAN WHAT WE HAVE
BEEN EXPERIENCING IN THE RECENT PAST.

COLD AIR ADVECTION AND WNW FLOW ALOFT WITH AND BEHIND THE FRONT AND
TO THE SOUTH OF A DEVELOPING UPPER LOW OVER VANCOUVER ISLAND THAT
WILL TRACK ESE WILL COMBINE TO GIVE A GOOD GALE TO THE STRAIT OF
JUAN DE FUCA AND W TO NW WINDS 20-35 MPH WITH GUSTS TO 45 MPH TO THE
ADMIRALTY INLET AREA. THE STRONGEST WINDS ARE LIKELY TO OCCUR ON THE
WEST SIDE OF WHIDBEY ISLAND.

A WIND ADVISORY HAS BEEN ISSUED FROM 2 PM THIS AFTERNOON TO 1 AM PDT
WEDNESDAY FOR THE ADMIRALTY INLET AREA. OTHER AREAS AROUND WESTERN
WASHINGTON WILL SEE BREEZY TO LOCALLY WINDY CONDITIONS LATE THIS
AFTERNOON AND EVENING AS WELL. A SPECIAL WEATHER STATEMENT IS ALSO
BEING ISSUED FOR THE MOUNTAINS FOR THE EXPECTATION OF SHARPLY COLDER
WEATHER THERE AND A COUPLE OF INCHES OF SNOW ABOVE ABOUT 3500 FEET.

ANOTHER FRONTAL SYSTEM WILL MOVE ACROSS THE AREA THURSDAY WITH RAIN
LIKELY ON THE COAST AND A CHANCE OF RAIN INLAND. COOL WEATHER WITH A
CHANCE OF SHOWERS IS EXPECTED ON FRIDAY. ALBRECHT

.LONG TERM...MODELS ARE RATHER CONSISTENT IN DIGGING A DEEP 515 DAM
500 MB LOW TO AROUND 50N 145W SATURDAY NIGHT AND SUNDAY AS COLD AIR
DUMPING OUT OF THE BERING SEA MOVES SOUTHEAST INTO THE GULF OF
ALASKA. FLOW TO THE SOUTH OF THE SPRAWLING UPPER LOW TO OUR WEST
WILL TAP INTO SOME TROPICAL OR SUBTROPICAL MOISTURE NEAR HAWAII AND
WRAP IT NE INTO OUR AREA THIS WEEKEND. OVER THE WEEKEND...3 TO 5
INCHES OF RAIN COULD FALL OVER THE OLYMPICS AND NORTH CASCADES WITH
A INCH OR TWO POSSIBLE IN THE LOWLANDS. EXPECT TEMPERATURES TO
MODERATE SOMEWHAT OVER THE WEEKEND...BUT HEIGHTS REMAIN LOW ENOUGH
SO THAT SNOW LEVELS ONLY BRIEFLY RISE TO OVER 6000 FEET. MODEL
CONSISTENCY AND CONTINUITY BEYOND SUNDAY IS POOR. NO MAJOR CHANGES
WERE MADE TO THE EXTENDED FORECAST. ALBRECHT

&&

.AVIATION...WESTERLY FLOW ALOFT WILL BECOME SOUTHWEST THIS MORNING
AS AN UPPER LEVEL TROUGH APPROACHES FROM THE WEST. INCREASING LOW
LEVEL ONSHORE FLOW TODAY WILL HELP THE AIR MASS TO BECOME MOIST AT
LOW LEVELS THIS MORNING. MARINE STRATUS HAS MOVED ONTO THE NORTH
COAST AS OF 06Z...EXPECT IT TO SPREAD ONTO THE CENTRAL
COAST...CHEHALIS GAP AND SOUTH INTERIOR BY DAY BREAK. THE FORECAST
FOR THE CENTRAL SOUND REMAINS A BIT TRICKY WITH THIS PATTERN...THE
EXPECTATION REMAINS FOR LIMITED LOW CLOUDS FORMING AND REMAINING
SHORT LIVED THIS MORNING.

A WEAK COLD FRONT REMAINS ON TRACK TO MOVE THROUGH THE FORECAST AREA
THIS AFTERNOON...FOLLOWED BY AN UPPER LEVEL TROUGH TUESDAY NIGHT.
THIS WILL RESULT IN A SHORT PERIOD OF LIGHT RAIN AND SHOWERS
BEHIND THE FRONT. THE PRIMARY IMPACT WILL BE INCREASING LOW LEVEL
WINDS TODAY.

KSEA...LIGHT NORTH WINDS...BECOMING SOUTHERLY TO 8 KT LATE...THEN
SOUTHWEST 8 TO 12 KT BY THIS AFTERNOON. THIN MARINE STRATUS POSSIBLE
AT THE TERMINAL AROUND 13Z.

&&

.MARINE...STRENGTHENING ONSHORE GRADIENTS THIS MORNING HAVE ALREADY
PRODUCED GALE CONDITIONS IN THE CENTRAL AND EAST STRAIT THIS
MORNING. SMALL CRAFT ADVISORY WINDS REMAIN FORECAST FOR ALL
REMAINING AREA WATERS THROUGH TONIGHT AS A COLD FRONT WORKS THROUGH
THE COASTAL WATERS THIS AFTERNOON AND INLAND DURING THE EVENING.
EXPECT INCREASING NORTHWESTERLY WINDS OVER PARTS OF THE COASTAL
WATERS TO REACH GALE LEVELS BEHIND THE FRONT...WHILE GALE WESTERLIES
REMAIN FORECAST FOR THE CENTRAL AND EASTERN STRAIT TONIGHT. SMALL
CRAFT ADVISORY WINDS WILL CONTINUE FOR ALL OTHER MARINE ZONES
THROUGH MUCH OF TONIGHT.

A SECOND WEAK COLD FRONT WILL CROSS THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT...WITH A STRONGER FRONTAL SYSTEM EXPECTED TO REACH
THE AREA SATURDAY.


&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WIND ADVISORY ADMIRALTY INLET AREA 2 PM THIS AFTERNOON UNTIL 1
AM       PDT WEDNESDAY.
PZ...GALE WARNING THROUGH TONIGHT CENTRAL AND EASTERN STRAIT.
     GALE WARNING FOR TONIGHT COASTAL WATERS ZONES 150 170 173.
     SMALL CRAFT ADVISORY ALL OTHER WATERS THROUGH TONIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML














000
FXUS66 KPQR 210935
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
234 AM PDT TUE APR 21 2015

.SYNOPSIS...AN UPPER TROUGH WILL REPLACE THE UPPER RIDGE TODAY AND
THERE WILL BE A CHANGE TO COOLER AND MOISTER WEATHER. TEMPERATURES
WILL COOL TO THE SEASONAL NORMALS BY WEDNESDAY. A SERIES OF WEAK
FRONTS WILL RESULT IN PERIODS OF LIGHT RAIN THIS AFTERNOON THROUGH
FRIDAY. A MORE ORGANIZED FRONT WILL MOVE ACROSS THE REGION THIS
WEEKEND.
&&

.SHORT TERM...TODAY THROUGH FRIDAY...THE UPPER RIDGE AXIS IS
CURRENTLY OVER THE CASCADES ALLOWING AN UPPER TROUGH OVER THE NE
PACIFIC TO APPROACH THE COAST. MARINE CLOUDS HAVE FILLED IN OVER THE
CENTRAL OREGON COAST AND COAST RANGE EARLY THIS MORNING...BUT THE
NORTH OREGON AND WASHINGTON COAST ARE MOSTLY CLEAR. SATELLITE IMAGERY
SHOWS LOW CLOUDS AHEAD OF AN APPROACHING COLD FRONT QUICKLY
APPROACHING THE WASHINGTON AND NORTH OREGON COAST. THIS STRATUS WILL
MERGE WITH THE STRATUS ALREADY ESTABLISHED ALONG THE CENTRAL OREGON
COAST AND FILL IN THE ENTIRE COAST BY SUNRISE. THE MARINE LAYER WILL
DEEPEN AS THE UPPER TROUGH APPROACHES THIS MORNING...ALLOWING THE
MARINE CLOUDS TO PUSH FURTHER INLAND...INTO PARTS OF THE WILLAMETTE
VALLEY AFTER SUNRISE.

THE COLD FRONT WILL WEAKEN AS IT APPROACHES THE COAST...BUT MAY HOLD
TOGETHER ENOUGH TO GENERATE SOME DRIZZLE ALONG THE COAST THIS
MORNING...AND SOME SHOWERS INLAND THIS AFTERNOON. CLOUDIER SKIES AND
COOLING ALOFT WILL RESULT IN MUCH COOLER TEMPERATURES THIS AFTERNOON
COMPARED TO THE LAST FEW DAYS...WITH HIGH TEMPERATURES ALONG THE
COAST IN THE MID TO UPPER 50S AND INLAND TEMPERATURES IN THE LOW TO
MID 60S.

A CHANCE OF SHOWERS WILL CONTINUE TONIGHT INTO WEDNESDAY AS THE UPPER
TROUGH SWINGS OVER THE AREA. MOST OF THESE SHOWERS WILL BE LIMITED TO
THE HIGHER TERRAIN. SNOW LEVELS WILL LOWER TO AROUND 3000 FEET BY
WEDNESDAY MORNING...BUT THE PRECIPITATION TOTALS WILL BE SO LIGHT
THAT THERE IS NOT A CONCERN FOR SNOW AT THE PASSES. THE PRECIPITATION
WILL DECREASE FROM SOUTH TO NORTH WEDNESDAY AFTERNOON AND EVENING.

ANOTHER WEAK COLD FRONT WILL APPROACH WEDNESDAY NIGHT AND POSSIBLY
BRING SOME LIGHT RAIN AND MOUNTAIN SNOW TO THE REGION THURSDAY AND
THURSDAY NIGHT. A WEAK UPPER LEVEL TROUGH WILL MAINTAIN SHOWERS
FRIDAY. DAYTIME TEMPERATURES WILL REMAIN NEAR NORMAL...IN THE LOW 60S
INLAND AND IN THE 50S FOR THE COAST THURSDAY AND FRIDAY. TJ

.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO
STRUGGLE ON THE DETAILS...BUT SUGGEST A WETTER FRONTAL STORM SYSTEM
WILL SLOWLY SAG SOUTHWARD ACROSS THE AREA LATE SATURDAY THROUGH
SUNDAY NIGHT. AS A RESULT...POPS WERE INCREASED IN THE LIKELY TO
CATEGORICAL RANGE FOR THE PRIME WINDOW OF SATURDAY NIGHT AND SUNDAY.
BOTH MODELS SUGGEST ANOTHER STORM SYSTEM IS LIKELY NEXT WEEK...BUT
ONCE AGAIN DIFFER ON TIMING SO POPS WERE TRENDED MORE INTO THE HIGH
END CHANCE TO LOW END LIKELY RANGE. /NEUMAN
&&

.AVIATION...VFR INLAND WHILE AREAS OF IFR ON THE COAST. A WEAK
FRONT WILL PUSH ANOTHER BATCH OF STRATUS TO THE COAST. THIS IS
EXPECTED TO BRING CIGS AROUND 1500-2500 FEET TO THE COAST THROUGH
AT LEAST THIS EVENING. PORTIONS OF THE INTERIOR WILL PROBABLY SEE
MVFR CIGS BETWEEN ABOUT 15Z AND 20Z TUE. HOWEVER WESTERLY ONSHORE
FLOW MAY RETAIN OCCASIONAL MOUNTAIN OBSCURATION THROUGH THIS
EVENING.

KPDX AND APPROACHES...MVFR STRATUS AROUND 2000 FT AFFECTING THE
TERMINAL 16Z TO 20Z TUE. VFR RETURNS BY 20Z TUESDAY WITH NW WINDS
PICKING UP MID AFTERNOON INTO EARLY EVENING.  /MH
&&

.MARINE...A WEAK FRONT WILL BRING A SLIGHT WIND SHIFT ACROSS THE
WATERS THIS MORNING. THE MAIN EFFECT HOWEVER WILL BE INCREASE IN
NWLY WINDS INTO THE SMALL CRAFT ADVISORY CATEGORY WHICH SHOULD
LAST INTO WED MORNING.A MUCH STRONGER FRONT LOOKS TO MOVE
ACROSS THE WATERS OVER THE WEEKEND AND WILL LIKELY BRING GUSTY
SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING SEAS.

SEAS WILL ALSO INCREASE WITH NWLY SWELL EXCEEDING 10 FT LATER THIS
AFTERNOON AND PEAK AROUND 10 TO 12 FT TONIGHT BEFORE SUBSIDING
BELOW 10 FT WED EVENING. THIS WILL LEAD TO ROUGH BAR DURING THE
NEXT FEW EBBS. WILL HAVE TO WATCH THE TONIGHT PERIOD IF SEAS RISE
A LITTLE HIGHER THAN ANTICIPATED ROUGH BAR CONDITIONS MAY OCCUR
DURING NON EBB TIME. /MH
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM THIS MORNING TO NOON
     PDT WEDNESDAY FOR WATERS FROM CAPE SHOALWATER WA TO FLORENCE
     OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM THIS
     AFTERNOON TO 6 PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE
     SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM THIS AFTERNOON TO NOON
     PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     6 AM TO 10 AM PDT THIS MORNING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     7 PM TO 10 PM PDT THIS EVENING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     5 AM TO 10 AM PDT WEDNESDAY.
&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 210935
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
234 AM PDT TUE APR 21 2015

.SYNOPSIS...AN UPPER TROUGH WILL REPLACE THE UPPER RIDGE TODAY AND
THERE WILL BE A CHANGE TO COOLER AND MOISTER WEATHER. TEMPERATURES
WILL COOL TO THE SEASONAL NORMALS BY WEDNESDAY. A SERIES OF WEAK
FRONTS WILL RESULT IN PERIODS OF LIGHT RAIN THIS AFTERNOON THROUGH
FRIDAY. A MORE ORGANIZED FRONT WILL MOVE ACROSS THE REGION THIS
WEEKEND.
&&

.SHORT TERM...TODAY THROUGH FRIDAY...THE UPPER RIDGE AXIS IS
CURRENTLY OVER THE CASCADES ALLOWING AN UPPER TROUGH OVER THE NE
PACIFIC TO APPROACH THE COAST. MARINE CLOUDS HAVE FILLED IN OVER THE
CENTRAL OREGON COAST AND COAST RANGE EARLY THIS MORNING...BUT THE
NORTH OREGON AND WASHINGTON COAST ARE MOSTLY CLEAR. SATELLITE IMAGERY
SHOWS LOW CLOUDS AHEAD OF AN APPROACHING COLD FRONT QUICKLY
APPROACHING THE WASHINGTON AND NORTH OREGON COAST. THIS STRATUS WILL
MERGE WITH THE STRATUS ALREADY ESTABLISHED ALONG THE CENTRAL OREGON
COAST AND FILL IN THE ENTIRE COAST BY SUNRISE. THE MARINE LAYER WILL
DEEPEN AS THE UPPER TROUGH APPROACHES THIS MORNING...ALLOWING THE
MARINE CLOUDS TO PUSH FURTHER INLAND...INTO PARTS OF THE WILLAMETTE
VALLEY AFTER SUNRISE.

THE COLD FRONT WILL WEAKEN AS IT APPROACHES THE COAST...BUT MAY HOLD
TOGETHER ENOUGH TO GENERATE SOME DRIZZLE ALONG THE COAST THIS
MORNING...AND SOME SHOWERS INLAND THIS AFTERNOON. CLOUDIER SKIES AND
COOLING ALOFT WILL RESULT IN MUCH COOLER TEMPERATURES THIS AFTERNOON
COMPARED TO THE LAST FEW DAYS...WITH HIGH TEMPERATURES ALONG THE
COAST IN THE MID TO UPPER 50S AND INLAND TEMPERATURES IN THE LOW TO
MID 60S.

A CHANCE OF SHOWERS WILL CONTINUE TONIGHT INTO WEDNESDAY AS THE UPPER
TROUGH SWINGS OVER THE AREA. MOST OF THESE SHOWERS WILL BE LIMITED TO
THE HIGHER TERRAIN. SNOW LEVELS WILL LOWER TO AROUND 3000 FEET BY
WEDNESDAY MORNING...BUT THE PRECIPITATION TOTALS WILL BE SO LIGHT
THAT THERE IS NOT A CONCERN FOR SNOW AT THE PASSES. THE PRECIPITATION
WILL DECREASE FROM SOUTH TO NORTH WEDNESDAY AFTERNOON AND EVENING.

ANOTHER WEAK COLD FRONT WILL APPROACH WEDNESDAY NIGHT AND POSSIBLY
BRING SOME LIGHT RAIN AND MOUNTAIN SNOW TO THE REGION THURSDAY AND
THURSDAY NIGHT. A WEAK UPPER LEVEL TROUGH WILL MAINTAIN SHOWERS
FRIDAY. DAYTIME TEMPERATURES WILL REMAIN NEAR NORMAL...IN THE LOW 60S
INLAND AND IN THE 50S FOR THE COAST THURSDAY AND FRIDAY. TJ

.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO
STRUGGLE ON THE DETAILS...BUT SUGGEST A WETTER FRONTAL STORM SYSTEM
WILL SLOWLY SAG SOUTHWARD ACROSS THE AREA LATE SATURDAY THROUGH
SUNDAY NIGHT. AS A RESULT...POPS WERE INCREASED IN THE LIKELY TO
CATEGORICAL RANGE FOR THE PRIME WINDOW OF SATURDAY NIGHT AND SUNDAY.
BOTH MODELS SUGGEST ANOTHER STORM SYSTEM IS LIKELY NEXT WEEK...BUT
ONCE AGAIN DIFFER ON TIMING SO POPS WERE TRENDED MORE INTO THE HIGH
END CHANCE TO LOW END LIKELY RANGE. /NEUMAN
&&

.AVIATION...VFR INLAND WHILE AREAS OF IFR ON THE COAST. A WEAK
FRONT WILL PUSH ANOTHER BATCH OF STRATUS TO THE COAST. THIS IS
EXPECTED TO BRING CIGS AROUND 1500-2500 FEET TO THE COAST THROUGH
AT LEAST THIS EVENING. PORTIONS OF THE INTERIOR WILL PROBABLY SEE
MVFR CIGS BETWEEN ABOUT 15Z AND 20Z TUE. HOWEVER WESTERLY ONSHORE
FLOW MAY RETAIN OCCASIONAL MOUNTAIN OBSCURATION THROUGH THIS
EVENING.

KPDX AND APPROACHES...MVFR STRATUS AROUND 2000 FT AFFECTING THE
TERMINAL 16Z TO 20Z TUE. VFR RETURNS BY 20Z TUESDAY WITH NW WINDS
PICKING UP MID AFTERNOON INTO EARLY EVENING.  /MH
&&

.MARINE...A WEAK FRONT WILL BRING A SLIGHT WIND SHIFT ACROSS THE
WATERS THIS MORNING. THE MAIN EFFECT HOWEVER WILL BE INCREASE IN
NWLY WINDS INTO THE SMALL CRAFT ADVISORY CATEGORY WHICH SHOULD
LAST INTO WED MORNING.A MUCH STRONGER FRONT LOOKS TO MOVE
ACROSS THE WATERS OVER THE WEEKEND AND WILL LIKELY BRING GUSTY
SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING SEAS.

SEAS WILL ALSO INCREASE WITH NWLY SWELL EXCEEDING 10 FT LATER THIS
AFTERNOON AND PEAK AROUND 10 TO 12 FT TONIGHT BEFORE SUBSIDING
BELOW 10 FT WED EVENING. THIS WILL LEAD TO ROUGH BAR DURING THE
NEXT FEW EBBS. WILL HAVE TO WATCH THE TONIGHT PERIOD IF SEAS RISE
A LITTLE HIGHER THAN ANTICIPATED ROUGH BAR CONDITIONS MAY OCCUR
DURING NON EBB TIME. /MH
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM THIS MORNING TO NOON
     PDT WEDNESDAY FOR WATERS FROM CAPE SHOALWATER WA TO FLORENCE
     OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM THIS
     AFTERNOON TO 6 PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE
     SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM THIS AFTERNOON TO NOON
     PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     6 AM TO 10 AM PDT THIS MORNING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     7 PM TO 10 PM PDT THIS EVENING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     5 AM TO 10 AM PDT WEDNESDAY.
&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 210935
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
234 AM PDT TUE APR 21 2015

.SYNOPSIS...AN UPPER TROUGH WILL REPLACE THE UPPER RIDGE TODAY AND
THERE WILL BE A CHANGE TO COOLER AND MOISTER WEATHER. TEMPERATURES
WILL COOL TO THE SEASONAL NORMALS BY WEDNESDAY. A SERIES OF WEAK
FRONTS WILL RESULT IN PERIODS OF LIGHT RAIN THIS AFTERNOON THROUGH
FRIDAY. A MORE ORGANIZED FRONT WILL MOVE ACROSS THE REGION THIS
WEEKEND.
&&

.SHORT TERM...TODAY THROUGH FRIDAY...THE UPPER RIDGE AXIS IS
CURRENTLY OVER THE CASCADES ALLOWING AN UPPER TROUGH OVER THE NE
PACIFIC TO APPROACH THE COAST. MARINE CLOUDS HAVE FILLED IN OVER THE
CENTRAL OREGON COAST AND COAST RANGE EARLY THIS MORNING...BUT THE
NORTH OREGON AND WASHINGTON COAST ARE MOSTLY CLEAR. SATELLITE IMAGERY
SHOWS LOW CLOUDS AHEAD OF AN APPROACHING COLD FRONT QUICKLY
APPROACHING THE WASHINGTON AND NORTH OREGON COAST. THIS STRATUS WILL
MERGE WITH THE STRATUS ALREADY ESTABLISHED ALONG THE CENTRAL OREGON
COAST AND FILL IN THE ENTIRE COAST BY SUNRISE. THE MARINE LAYER WILL
DEEPEN AS THE UPPER TROUGH APPROACHES THIS MORNING...ALLOWING THE
MARINE CLOUDS TO PUSH FURTHER INLAND...INTO PARTS OF THE WILLAMETTE
VALLEY AFTER SUNRISE.

THE COLD FRONT WILL WEAKEN AS IT APPROACHES THE COAST...BUT MAY HOLD
TOGETHER ENOUGH TO GENERATE SOME DRIZZLE ALONG THE COAST THIS
MORNING...AND SOME SHOWERS INLAND THIS AFTERNOON. CLOUDIER SKIES AND
COOLING ALOFT WILL RESULT IN MUCH COOLER TEMPERATURES THIS AFTERNOON
COMPARED TO THE LAST FEW DAYS...WITH HIGH TEMPERATURES ALONG THE
COAST IN THE MID TO UPPER 50S AND INLAND TEMPERATURES IN THE LOW TO
MID 60S.

A CHANCE OF SHOWERS WILL CONTINUE TONIGHT INTO WEDNESDAY AS THE UPPER
TROUGH SWINGS OVER THE AREA. MOST OF THESE SHOWERS WILL BE LIMITED TO
THE HIGHER TERRAIN. SNOW LEVELS WILL LOWER TO AROUND 3000 FEET BY
WEDNESDAY MORNING...BUT THE PRECIPITATION TOTALS WILL BE SO LIGHT
THAT THERE IS NOT A CONCERN FOR SNOW AT THE PASSES. THE PRECIPITATION
WILL DECREASE FROM SOUTH TO NORTH WEDNESDAY AFTERNOON AND EVENING.

ANOTHER WEAK COLD FRONT WILL APPROACH WEDNESDAY NIGHT AND POSSIBLY
BRING SOME LIGHT RAIN AND MOUNTAIN SNOW TO THE REGION THURSDAY AND
THURSDAY NIGHT. A WEAK UPPER LEVEL TROUGH WILL MAINTAIN SHOWERS
FRIDAY. DAYTIME TEMPERATURES WILL REMAIN NEAR NORMAL...IN THE LOW 60S
INLAND AND IN THE 50S FOR THE COAST THURSDAY AND FRIDAY. TJ

.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO
STRUGGLE ON THE DETAILS...BUT SUGGEST A WETTER FRONTAL STORM SYSTEM
WILL SLOWLY SAG SOUTHWARD ACROSS THE AREA LATE SATURDAY THROUGH
SUNDAY NIGHT. AS A RESULT...POPS WERE INCREASED IN THE LIKELY TO
CATEGORICAL RANGE FOR THE PRIME WINDOW OF SATURDAY NIGHT AND SUNDAY.
BOTH MODELS SUGGEST ANOTHER STORM SYSTEM IS LIKELY NEXT WEEK...BUT
ONCE AGAIN DIFFER ON TIMING SO POPS WERE TRENDED MORE INTO THE HIGH
END CHANCE TO LOW END LIKELY RANGE. /NEUMAN
&&

.AVIATION...VFR INLAND WHILE AREAS OF IFR ON THE COAST. A WEAK
FRONT WILL PUSH ANOTHER BATCH OF STRATUS TO THE COAST. THIS IS
EXPECTED TO BRING CIGS AROUND 1500-2500 FEET TO THE COAST THROUGH
AT LEAST THIS EVENING. PORTIONS OF THE INTERIOR WILL PROBABLY SEE
MVFR CIGS BETWEEN ABOUT 15Z AND 20Z TUE. HOWEVER WESTERLY ONSHORE
FLOW MAY RETAIN OCCASIONAL MOUNTAIN OBSCURATION THROUGH THIS
EVENING.

KPDX AND APPROACHES...MVFR STRATUS AROUND 2000 FT AFFECTING THE
TERMINAL 16Z TO 20Z TUE. VFR RETURNS BY 20Z TUESDAY WITH NW WINDS
PICKING UP MID AFTERNOON INTO EARLY EVENING.  /MH
&&

.MARINE...A WEAK FRONT WILL BRING A SLIGHT WIND SHIFT ACROSS THE
WATERS THIS MORNING. THE MAIN EFFECT HOWEVER WILL BE INCREASE IN
NWLY WINDS INTO THE SMALL CRAFT ADVISORY CATEGORY WHICH SHOULD
LAST INTO WED MORNING.A MUCH STRONGER FRONT LOOKS TO MOVE
ACROSS THE WATERS OVER THE WEEKEND AND WILL LIKELY BRING GUSTY
SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING SEAS.

SEAS WILL ALSO INCREASE WITH NWLY SWELL EXCEEDING 10 FT LATER THIS
AFTERNOON AND PEAK AROUND 10 TO 12 FT TONIGHT BEFORE SUBSIDING
BELOW 10 FT WED EVENING. THIS WILL LEAD TO ROUGH BAR DURING THE
NEXT FEW EBBS. WILL HAVE TO WATCH THE TONIGHT PERIOD IF SEAS RISE
A LITTLE HIGHER THAN ANTICIPATED ROUGH BAR CONDITIONS MAY OCCUR
DURING NON EBB TIME. /MH
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM THIS MORNING TO NOON
     PDT WEDNESDAY FOR WATERS FROM CAPE SHOALWATER WA TO FLORENCE
     OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM THIS
     AFTERNOON TO 6 PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE
     SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM THIS AFTERNOON TO NOON
     PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     6 AM TO 10 AM PDT THIS MORNING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     7 PM TO 10 PM PDT THIS EVENING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     5 AM TO 10 AM PDT WEDNESDAY.
&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KOTX 210934
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
234 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
Today through Wednesday...The ridge axis, located over central
Washington as of 2 am, will be nudged east today as an upper
trough swings toward the coast today. The trough will pass
through the region tonight into Wednesday, bringing a chance of
showers to portions of the forecast area. Models are now trending
toward the GFS solution of a closed low tracking across the
forecast area, leaving the ECMWF as the outlier with an open wave
clipping the northern zones. PoPs have been trended toward the
consensus but this will not be a slam dunk for showers across
central WA. Moisture should reach the Cascade crest late this
afternoon or early this evening and afternoon instability may be
enough to produce a thunderstorm or two. The cold front weakens as
it crosses the Cascades and encounters dry air while westerly flow
acts to rain shadow the east slopes and basin. There does appear
to be a reinforcing shot of moisture moving up from the south that
will bring a chance of showers to the NE Blue Mts overnight. The
best chance for showers will be on Wednesday as the trough
dynamics interact with upslope flow for the rising terrain east of
the basin. There will also be a chance of thunderstorms for the
Idaho panhandle as the cold pool aloft destabilizes the
atmosphere.

The breakdown of the ridge will also result in gusty winds for
the Cascade valleys starting this afternoon as the cooler more
dense marine air invades the gap valleys. Gusty winds will spread
to the Waterville Plateau this evening and continue overnight. The
eastern basin and Palouse will see breezy conditions with the
frontal passage Wednesday. Generally expect sustained winds of 15
to 25 mph with gusts of 30 to 40 mph. Relative humidity should be
recovering by the time the winds increase since it looks like the
marine layer will be deep enough for some of the moisture to make
it over the Cascades.

Temperatures will continue the warming trend today then cool
significantly for Wednesday with the trough passage when most
valley locations will be in the upper 50s to mid 60s. /Kelch

Wednesday night through Friday the forecast will follow a blend of
the ECMWF/Canadian/NAM. A very wrapped up closed low will track
northeast across the north Idaho Panhandle and points further
north and east. Meanwhile another deep closed system will drop
south along the B.C. Coast Thursday, then fill as the low moves
along the Canadian border. This low will tap into slightly deeper
Pacific moisture. The cold core Wednesday evening associated with
the closed low will increase lapse rates and destabilize the lower
levels. This will result in some active showers across the
northeast zones Wednesday evening. Surfaces based cape is present
but not overly deep, but there may be enough instability to
support a few lightning strikes through the evening hours.
Thunderstorms were already in the forecast, but were trimmed back
to mainly boundary county up near the Canadian border. Showers
will remain in the forecast with the secondary low, mainly across
the north Idaho Panhandle, and stretching as far west as the
Northeast WA mountains up near the Canadian border. A second area
of showers will be along the Cascade crest. Temperatures will cool
off into the mid 50s to mid 60s, which are very close to seasonal
averages.

Friday night and Saturday the region will be in between weather
systems with weak and short lived high pressure tracking across
the region. Some light orographic mountain showers will be
possible for the Panhandle mountains and across the Cascades,
otherwise expect a period of dry but continued cool weather.

Saturday night through Tuesday a much deeper upper level low will
move into the eastern Pacific and stall. At this time it appears
as if the low may not move inland until mid-week if not later, but
there is much uncertainty in the model solutions through this
period. What we do know is the southwesterly flow will tap into a
very deep tropical atmospheric river Saturday night that looks
like it will linger through at least Tuesday. PWATS go up to
around an inch which is well above normal. A deep southwest
moisture tap of this magnitude will not need much in the way of a
lifting process to wring out any and all moisture across the
region. It looks like we will be in for an extended period of
moderate stratiform precipitation Sunday through Tuesday.
Southwest flow will warm temperatures, but these will likely be
inhibited somewhat by cloud cover and widespread rain and not
reach potential. South-southwest winds will become breezy Saturday
night and Sunday and remain elevated at least through Monday.
Tobin.

&&

.AVIATION...
06Z TAFS: High pressure will result in VFR conditions through 06Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. /SVH


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 210934
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
234 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
Today through Wednesday...The ridge axis, located over central
Washington as of 2 am, will be nudged east today as an upper
trough swings toward the coast today. The trough will pass
through the region tonight into Wednesday, bringing a chance of
showers to portions of the forecast area. Models are now trending
toward the GFS solution of a closed low tracking across the
forecast area, leaving the ECMWF as the outlier with an open wave
clipping the northern zones. PoPs have been trended toward the
consensus but this will not be a slam dunk for showers across
central WA. Moisture should reach the Cascade crest late this
afternoon or early this evening and afternoon instability may be
enough to produce a thunderstorm or two. The cold front weakens as
it crosses the Cascades and encounters dry air while westerly flow
acts to rain shadow the east slopes and basin. There does appear
to be a reinforcing shot of moisture moving up from the south that
will bring a chance of showers to the NE Blue Mts overnight. The
best chance for showers will be on Wednesday as the trough
dynamics interact with upslope flow for the rising terrain east of
the basin. There will also be a chance of thunderstorms for the
Idaho panhandle as the cold pool aloft destabilizes the
atmosphere.

The breakdown of the ridge will also result in gusty winds for
the Cascade valleys starting this afternoon as the cooler more
dense marine air invades the gap valleys. Gusty winds will spread
to the Waterville Plateau this evening and continue overnight. The
eastern basin and Palouse will see breezy conditions with the
frontal passage Wednesday. Generally expect sustained winds of 15
to 25 mph with gusts of 30 to 40 mph. Relative humidity should be
recovering by the time the winds increase since it looks like the
marine layer will be deep enough for some of the moisture to make
it over the Cascades.

Temperatures will continue the warming trend today then cool
significantly for Wednesday with the trough passage when most
valley locations will be in the upper 50s to mid 60s. /Kelch

Wednesday night through Friday the forecast will follow a blend of
the ECMWF/Canadian/NAM. A very wrapped up closed low will track
northeast across the north Idaho Panhandle and points further
north and east. Meanwhile another deep closed system will drop
south along the B.C. Coast Thursday, then fill as the low moves
along the Canadian border. This low will tap into slightly deeper
Pacific moisture. The cold core Wednesday evening associated with
the closed low will increase lapse rates and destabilize the lower
levels. This will result in some active showers across the
northeast zones Wednesday evening. Surfaces based cape is present
but not overly deep, but there may be enough instability to
support a few lightning strikes through the evening hours.
Thunderstorms were already in the forecast, but were trimmed back
to mainly boundary county up near the Canadian border. Showers
will remain in the forecast with the secondary low, mainly across
the north Idaho Panhandle, and stretching as far west as the
Northeast WA mountains up near the Canadian border. A second area
of showers will be along the Cascade crest. Temperatures will cool
off into the mid 50s to mid 60s, which are very close to seasonal
averages.

Friday night and Saturday the region will be in between weather
systems with weak and short lived high pressure tracking across
the region. Some light orographic mountain showers will be
possible for the Panhandle mountains and across the Cascades,
otherwise expect a period of dry but continued cool weather.

Saturday night through Tuesday a much deeper upper level low will
move into the eastern Pacific and stall. At this time it appears
as if the low may not move inland until mid-week if not later, but
there is much uncertainty in the model solutions through this
period. What we do know is the southwesterly flow will tap into a
very deep tropical atmospheric river Saturday night that looks
like it will linger through at least Tuesday. PWATS go up to
around an inch which is well above normal. A deep southwest
moisture tap of this magnitude will not need much in the way of a
lifting process to wring out any and all moisture across the
region. It looks like we will be in for an extended period of
moderate stratiform precipitation Sunday through Tuesday.
Southwest flow will warm temperatures, but these will likely be
inhibited somewhat by cloud cover and widespread rain and not
reach potential. South-southwest winds will become breezy Saturday
night and Sunday and remain elevated at least through Monday.
Tobin.

&&

.AVIATION...
06Z TAFS: High pressure will result in VFR conditions through 06Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. /SVH


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 210934
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
234 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
Today through Wednesday...The ridge axis, located over central
Washington as of 2 am, will be nudged east today as an upper
trough swings toward the coast today. The trough will pass
through the region tonight into Wednesday, bringing a chance of
showers to portions of the forecast area. Models are now trending
toward the GFS solution of a closed low tracking across the
forecast area, leaving the ECMWF as the outlier with an open wave
clipping the northern zones. PoPs have been trended toward the
consensus but this will not be a slam dunk for showers across
central WA. Moisture should reach the Cascade crest late this
afternoon or early this evening and afternoon instability may be
enough to produce a thunderstorm or two. The cold front weakens as
it crosses the Cascades and encounters dry air while westerly flow
acts to rain shadow the east slopes and basin. There does appear
to be a reinforcing shot of moisture moving up from the south that
will bring a chance of showers to the NE Blue Mts overnight. The
best chance for showers will be on Wednesday as the trough
dynamics interact with upslope flow for the rising terrain east of
the basin. There will also be a chance of thunderstorms for the
Idaho panhandle as the cold pool aloft destabilizes the
atmosphere.

The breakdown of the ridge will also result in gusty winds for
the Cascade valleys starting this afternoon as the cooler more
dense marine air invades the gap valleys. Gusty winds will spread
to the Waterville Plateau this evening and continue overnight. The
eastern basin and Palouse will see breezy conditions with the
frontal passage Wednesday. Generally expect sustained winds of 15
to 25 mph with gusts of 30 to 40 mph. Relative humidity should be
recovering by the time the winds increase since it looks like the
marine layer will be deep enough for some of the moisture to make
it over the Cascades.

Temperatures will continue the warming trend today then cool
significantly for Wednesday with the trough passage when most
valley locations will be in the upper 50s to mid 60s. /Kelch

Wednesday night through Friday the forecast will follow a blend of
the ECMWF/Canadian/NAM. A very wrapped up closed low will track
northeast across the north Idaho Panhandle and points further
north and east. Meanwhile another deep closed system will drop
south along the B.C. Coast Thursday, then fill as the low moves
along the Canadian border. This low will tap into slightly deeper
Pacific moisture. The cold core Wednesday evening associated with
the closed low will increase lapse rates and destabilize the lower
levels. This will result in some active showers across the
northeast zones Wednesday evening. Surfaces based cape is present
but not overly deep, but there may be enough instability to
support a few lightning strikes through the evening hours.
Thunderstorms were already in the forecast, but were trimmed back
to mainly boundary county up near the Canadian border. Showers
will remain in the forecast with the secondary low, mainly across
the north Idaho Panhandle, and stretching as far west as the
Northeast WA mountains up near the Canadian border. A second area
of showers will be along the Cascade crest. Temperatures will cool
off into the mid 50s to mid 60s, which are very close to seasonal
averages.

Friday night and Saturday the region will be in between weather
systems with weak and short lived high pressure tracking across
the region. Some light orographic mountain showers will be
possible for the Panhandle mountains and across the Cascades,
otherwise expect a period of dry but continued cool weather.

Saturday night through Tuesday a much deeper upper level low will
move into the eastern Pacific and stall. At this time it appears
as if the low may not move inland until mid-week if not later, but
there is much uncertainty in the model solutions through this
period. What we do know is the southwesterly flow will tap into a
very deep tropical atmospheric river Saturday night that looks
like it will linger through at least Tuesday. PWATS go up to
around an inch which is well above normal. A deep southwest
moisture tap of this magnitude will not need much in the way of a
lifting process to wring out any and all moisture across the
region. It looks like we will be in for an extended period of
moderate stratiform precipitation Sunday through Tuesday.
Southwest flow will warm temperatures, but these will likely be
inhibited somewhat by cloud cover and widespread rain and not
reach potential. South-southwest winds will become breezy Saturday
night and Sunday and remain elevated at least through Monday.
Tobin.

&&

.AVIATION...
06Z TAFS: High pressure will result in VFR conditions through 06Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. /SVH


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 210934
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
234 AM PDT TUE APR 21 2015

.SYNOPSIS...

Today will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday. A stronger
weather disturbance will result in widespread and possibly
moderate precipitation Sunday and lingering into the new week.


&&

.DISCUSSION...
Today through Wednesday...The ridge axis, located over central
Washington as of 2 am, will be nudged east today as an upper
trough swings toward the coast today. The trough will pass
through the region tonight into Wednesday, bringing a chance of
showers to portions of the forecast area. Models are now trending
toward the GFS solution of a closed low tracking across the
forecast area, leaving the ECMWF as the outlier with an open wave
clipping the northern zones. PoPs have been trended toward the
consensus but this will not be a slam dunk for showers across
central WA. Moisture should reach the Cascade crest late this
afternoon or early this evening and afternoon instability may be
enough to produce a thunderstorm or two. The cold front weakens as
it crosses the Cascades and encounters dry air while westerly flow
acts to rain shadow the east slopes and basin. There does appear
to be a reinforcing shot of moisture moving up from the south that
will bring a chance of showers to the NE Blue Mts overnight. The
best chance for showers will be on Wednesday as the trough
dynamics interact with upslope flow for the rising terrain east of
the basin. There will also be a chance of thunderstorms for the
Idaho panhandle as the cold pool aloft destabilizes the
atmosphere.

The breakdown of the ridge will also result in gusty winds for
the Cascade valleys starting this afternoon as the cooler more
dense marine air invades the gap valleys. Gusty winds will spread
to the Waterville Plateau this evening and continue overnight. The
eastern basin and Palouse will see breezy conditions with the
frontal passage Wednesday. Generally expect sustained winds of 15
to 25 mph with gusts of 30 to 40 mph. Relative humidity should be
recovering by the time the winds increase since it looks like the
marine layer will be deep enough for some of the moisture to make
it over the Cascades.

Temperatures will continue the warming trend today then cool
significantly for Wednesday with the trough passage when most
valley locations will be in the upper 50s to mid 60s. /Kelch

Wednesday night through Friday the forecast will follow a blend of
the ECMWF/Canadian/NAM. A very wrapped up closed low will track
northeast across the north Idaho Panhandle and points further
north and east. Meanwhile another deep closed system will drop
south along the B.C. Coast Thursday, then fill as the low moves
along the Canadian border. This low will tap into slightly deeper
Pacific moisture. The cold core Wednesday evening associated with
the closed low will increase lapse rates and destabilize the lower
levels. This will result in some active showers across the
northeast zones Wednesday evening. Surfaces based cape is present
but not overly deep, but there may be enough instability to
support a few lightning strikes through the evening hours.
Thunderstorms were already in the forecast, but were trimmed back
to mainly boundary county up near the Canadian border. Showers
will remain in the forecast with the secondary low, mainly across
the north Idaho Panhandle, and stretching as far west as the
Northeast WA mountains up near the Canadian border. A second area
of showers will be along the Cascade crest. Temperatures will cool
off into the mid 50s to mid 60s, which are very close to seasonal
averages.

Friday night and Saturday the region will be in between weather
systems with weak and short lived high pressure tracking across
the region. Some light orographic mountain showers will be
possible for the Panhandle mountains and across the Cascades,
otherwise expect a period of dry but continued cool weather.

Saturday night through Tuesday a much deeper upper level low will
move into the eastern Pacific and stall. At this time it appears
as if the low may not move inland until mid-week if not later, but
there is much uncertainty in the model solutions through this
period. What we do know is the southwesterly flow will tap into a
very deep tropical atmospheric river Saturday night that looks
like it will linger through at least Tuesday. PWATS go up to
around an inch which is well above normal. A deep southwest
moisture tap of this magnitude will not need much in the way of a
lifting process to wring out any and all moisture across the
region. It looks like we will be in for an extended period of
moderate stratiform precipitation Sunday through Tuesday.
Southwest flow will warm temperatures, but these will likely be
inhibited somewhat by cloud cover and widespread rain and not
reach potential. South-southwest winds will become breezy Saturday
night and Sunday and remain elevated at least through Monday.
Tobin.

&&

.AVIATION...
06Z TAFS: High pressure will result in VFR conditions through 06Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. /SVH


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        74  49  59  36  60  41 /  10  10  20  10  10  20
Coeur d`Alene  73  43  60  34  60  37 /  10  10  30  20  10  20
Pullman        72  45  57  34  60  39 /  10  10  30  10  10  10
Lewiston       79  50  64  38  66  44 /   0  10  30  10  10  10
Colville       77  47  63  37  63  39 /  10  10  50  30  10  20
Sandpoint      72  40  59  33  59  34 /  10  10  30  30  20  20
Kellogg        71  43  57  34  60  36 /  10  10  40  20  10  20
Moses Lake     79  49  66  37  65  40 /   0  10  10   0  10  10
Wenatchee      77  53  65  41  64  44 /  10  10  10  10  10  10
Omak           78  47  64  35  64  38 /  10  10  30  10  10  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 210536
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1035 PM PDT MON APR 20 2015

.SYNOPSIS...

Tuesday will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday.

&&

.DISCUSSION...

Tonight through Tuesday night...The axis of the ridge of high
pressure influencing the area moves east tomorrow. It does this at
slow enough of a speed to allow for temperatures of the seven day
forecast to peak for most locations tomorrow. Late in the
afternoon and evening with the axis to the east a weak marine push
of sorts allows for winds to increase in the gaps of the cascades
and close proximity to them late Tuesday afternoon and overnight.
The weak push may also fire off a bit of spotty convective showers
and perhaps a thunderstorm or two. Minimum temperatures Tuesday
night should be on the warm side of normal given the mixing
brought about by the wind. /Pelatti

Wednesday: Cooler and breezy weather will arrive Tuesday night
into Wednesday. The high amplitude 500mb ridge responsible for our
recent warm weather will be replaced by a cool polar low
descending out of the Gulf of Alaska. A relatively high spread in
model solutions continues for a day 3 forecast leading to lower
than average confidence for precipitation chances and winds for
Wednesday. The GFS model continues to be an outlier digging an
upper low deeper south into Washington on Wednesday. The ECMWF,
Canadian and NAM models look to have a more reasonable progressive
solution. The deeper/slower low on GFS looks a bit suspect given
the strong upstream kicker in the Gulf of Alaska, so the forecast
for Wednesday and Thursday was largely based on the Canadian
which is a compromise between the ECMWF and NAM.

This Canadian compromise means less chance for thunderstorms since
the heart of the 500mb cold pool will only graze the northern
Washington zones. This solution also entrains a good deal of mid-
level dry air into the region on Wednesday limiting the amount of
deep layer instability. Precipitation chances region-wide don`t
look very impressive. The Canadian and ECMWF solutions are a bit
breezier, so winds have been increased. We will likely see a 10
to 12 degree cool down from Tuesday into Wednesday as chilly
maritime air is squeezed through the gaps in the Cascades. The
change in air mass will likely be accompanied by typical breezy
spring time winds between 15 and 20 mph with some wind prone areas
in the lee of the Cascades gusting in excess of 30 mph on
Wednesday.

Thursday: If we discount the GFS, Thursday has the potential to be
a relatively dry day with fairly light winds. Precipitation
chances have been trimmed, limited to 20 percent or less in the
mountainous. Light winds and a good chance for mainly clear skies
suggest a fairly chilly morning on Thursday. Sheltered areas in
the Idaho Panhandle and northeast Washington will have a good shot
at low to mid 30s...perhaps a frost.

Friday and Saturday: By Friday, the main longwave trough over the
Gulf of Alaska is expected to move into Washington or southern
British Columbia. Seasonably chilly temperatures and showers will
likely accompany the arrival of this broad polar trough. Our
temperature forecast for Friday into Saturday has been cooled in
line with MOS guidance.

Sunday and Monday: Given the model uncertainty in the Wednesday
through Saturday time frame, it is a bit unusual to see the GFS,
ECMWF, and Canadian come into better agreement early next week.
The model consensus is for a mild and wet pattern Sunday and
Monday as a subtropical moisture plume becomes planted over the
Pacific Northwest. Early next week looks like our best shot of
widespread precipitation during the next 7 to 10 day period.
/GKoch

&&

.AVIATION...
06Z TAFS: High pressure will result in VFR conditions through 06Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        46  74  50  61  36  62 /   0  10  10  20  10  10
Coeur d`Alene  41  73  44  62  34  62 /   0  10  10  20  20  10
Pullman        42  72  46  58  34  61 /   0  10  10  30  10  10
Lewiston       46  78  49  65  38  66 /   0   0  10  30  10  10
Colville       42  77  46  65  37  65 /   0  10  10  40  40  20
Sandpoint      38  72  40  61  33  60 /   0  10  10  30  30  20
Kellogg        40  71  43  59  34  62 /   0  10  10  30  20  20
Moses Lake     44  78  50  67  37  66 /   0  10  10  10   0  10
Wenatchee      51  77  53  65  41  65 /   0  10  10  10   0  10
Omak           44  77  47  65  35  64 /   0  10  10  30  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 210536
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1035 PM PDT MON APR 20 2015

.SYNOPSIS...

Tuesday will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday.

&&

.DISCUSSION...

Tonight through Tuesday night...The axis of the ridge of high
pressure influencing the area moves east tomorrow. It does this at
slow enough of a speed to allow for temperatures of the seven day
forecast to peak for most locations tomorrow. Late in the
afternoon and evening with the axis to the east a weak marine push
of sorts allows for winds to increase in the gaps of the cascades
and close proximity to them late Tuesday afternoon and overnight.
The weak push may also fire off a bit of spotty convective showers
and perhaps a thunderstorm or two. Minimum temperatures Tuesday
night should be on the warm side of normal given the mixing
brought about by the wind. /Pelatti

Wednesday: Cooler and breezy weather will arrive Tuesday night
into Wednesday. The high amplitude 500mb ridge responsible for our
recent warm weather will be replaced by a cool polar low
descending out of the Gulf of Alaska. A relatively high spread in
model solutions continues for a day 3 forecast leading to lower
than average confidence for precipitation chances and winds for
Wednesday. The GFS model continues to be an outlier digging an
upper low deeper south into Washington on Wednesday. The ECMWF,
Canadian and NAM models look to have a more reasonable progressive
solution. The deeper/slower low on GFS looks a bit suspect given
the strong upstream kicker in the Gulf of Alaska, so the forecast
for Wednesday and Thursday was largely based on the Canadian
which is a compromise between the ECMWF and NAM.

This Canadian compromise means less chance for thunderstorms since
the heart of the 500mb cold pool will only graze the northern
Washington zones. This solution also entrains a good deal of mid-
level dry air into the region on Wednesday limiting the amount of
deep layer instability. Precipitation chances region-wide don`t
look very impressive. The Canadian and ECMWF solutions are a bit
breezier, so winds have been increased. We will likely see a 10
to 12 degree cool down from Tuesday into Wednesday as chilly
maritime air is squeezed through the gaps in the Cascades. The
change in air mass will likely be accompanied by typical breezy
spring time winds between 15 and 20 mph with some wind prone areas
in the lee of the Cascades gusting in excess of 30 mph on
Wednesday.

Thursday: If we discount the GFS, Thursday has the potential to be
a relatively dry day with fairly light winds. Precipitation
chances have been trimmed, limited to 20 percent or less in the
mountainous. Light winds and a good chance for mainly clear skies
suggest a fairly chilly morning on Thursday. Sheltered areas in
the Idaho Panhandle and northeast Washington will have a good shot
at low to mid 30s...perhaps a frost.

Friday and Saturday: By Friday, the main longwave trough over the
Gulf of Alaska is expected to move into Washington or southern
British Columbia. Seasonably chilly temperatures and showers will
likely accompany the arrival of this broad polar trough. Our
temperature forecast for Friday into Saturday has been cooled in
line with MOS guidance.

Sunday and Monday: Given the model uncertainty in the Wednesday
through Saturday time frame, it is a bit unusual to see the GFS,
ECMWF, and Canadian come into better agreement early next week.
The model consensus is for a mild and wet pattern Sunday and
Monday as a subtropical moisture plume becomes planted over the
Pacific Northwest. Early next week looks like our best shot of
widespread precipitation during the next 7 to 10 day period.
/GKoch

&&

.AVIATION...
06Z TAFS: High pressure will result in VFR conditions through 06Z
Wednesday. A deepening marine layer west of the Cascade Mtns will
result in breezy northwesterly winds at KEAT late Tuesday
afternoon. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        46  74  50  61  36  62 /   0  10  10  20  10  10
Coeur d`Alene  41  73  44  62  34  62 /   0  10  10  20  20  10
Pullman        42  72  46  58  34  61 /   0  10  10  30  10  10
Lewiston       46  78  49  65  38  66 /   0   0  10  30  10  10
Colville       42  77  46  65  37  65 /   0  10  10  40  40  20
Sandpoint      38  72  40  61  33  60 /   0  10  10  30  30  20
Kellogg        40  71  43  59  34  62 /   0  10  10  30  20  20
Moses Lake     44  78  50  67  37  66 /   0  10  10  10   0  10
Wenatchee      51  77  53  65  41  65 /   0  10  10  10   0  10
Omak           44  77  47  65  35  64 /   0  10  10  30  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KSEW 210346
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
846 PM PDT MON APR 20 2015

.SYNOPSIS...AN UPPER LEVEL RIDGE WILL KEEPS SKIES MOSTLY CLEAR
TONIGHT. WEAK LOW LEVEL ONSHORE FLOW OVERNIGHT WILL ALLOW A FEW
AREAS OF LOW CLOUDS TO FORM OVER WESTERN WASHINGTON TUESDAY MORNING.
A WEAK FRONT WILL BRING CLOUDS AND A FEW SHOWERS TO THE COAST LATE
TUESDAY MORNING AND THEN OVER PUGET SOUND LATE IN THE DAY. AN UPPER
LEVEL TROUGH WILL FOLLOW TUESDAY NIGHT AND WEDNESDAY MORNING.
ANOTHER WEAK FRONT WILL BRING A FEW SHOWERS ON THURSDAY. MOIST
SOUTHWEST FLOW ALOFT WILL BRING PERIODS OF RAIN NEXT WEEKEND.

&&

.SHORT TERM...THE UPPER LEVEL RIDGE OVER W WA THIS EVENING WILL
SHIFT OVER N ID TUESDAY MORNING...ALLOWING THE WEAK FRONT JUST
OFFSHORE NEAR 130W TO MOVE TOWARD THE WA COAST. ONSHORE FLOW IS
INCREASING THIS EVENING AHEAD OF THE FRONT...WHICH IS VERY
REMINISCENT OF A SUMMER-TIME PATTERN. THERE WAS JUST A LITTLE RIBBON
OF STRATUS ALONG THE CENTRAL COASTLINE LATE THIS AFTERNOON AND
ONSHORE PRESSURE GRADIENTS HAVE ONLY MADE IT UP TO 1.0 TO 1.5
MB...SO IT DOES NOT LOOK LIKE THERE WILL BE A WHOLE LOT OF STRATUS
FORMING IN PLACE OVER THE INTERIOR TUESDAY MORNING. BEST GUESS IS
AREAS OF STRATUS THROUGH THE STRAIT AND OVER THE LOWER CHEHALIS
VALLEY MAINLY W OF SHELTON.

THE WEAK FRONT ALONG 130W THIS EVENING WILL REACH THE AREA ON
TUESDAY. MODELS HAVE THE LEADING EDGE OF THE FRONTAL CLOUDS REACHING
THE COAST AROUND LATE TUESDAY MORNING...AND PUGET SOUND LATE IN THE
AFTERNOON. THE FRONT SHOULD BE OVER THE CASCADES BY LATE EVENING.
FRONTAL PRECIPITATION WILL BE PRETTY SKIMPY...WITH LIGHT
ACCUMULATIONS ON THE COAST MAINLY UPSTREAM OF THE OLYMPICS. OVER THE
INTERIOR IT LOOKS LIKE MOST OF THE PRECIP WILL BE AROUND CENTRAL
PUGET SOUND WHERE A CONVERGENCE ZONE IS EXPECTED TO FORM...AND OVER
THE CASCADES WHERE LOW LEVEL W WINDS WILL GENERATE UPSLOPE FLOW.

AN UPPER LEVEL TROUGH WILL BE RIGHT BEHIND THE FRONT...CROSSING
PUGET SOUND EARLY WEDNESDAY MORNING...THEN MOVING OVER E WA
WEDNESDAY AFTERNOON. NAM HIGH RES SOUNDINGS INDICATE THE AIR MASS
WILL REMAIN STABLE WITH BOTH THE WEAK FRONT AND THE ASSOCIATED UPPER
LEVEL TROUGH. PRECIP ON WEDNESDAY BEHIND THE UPPER TROUGH SHOULD BE
MAINLY ASSOCIATED WITH THE CONVERGENCE ZONE...AND THOSE SHOWERS
SHOULD BE DIMINISHING BY AFTERNOON.

IT LOOKS LIKE WEDNESDAY AFTERNOON AND EVENING WILL BE MOSTLY DRY. A
SMALL WEAK UPPER LEVEL SHORTWAVE RIDGE WILL MOVE ACROSS THE
AREA...BUT THE BREAK WILL BE MOSTLY DUE TO THE GAP IN-BETWEEN
WEATHER SYSTEMS.

GFS AND ECMWF AGREE THAT A WEAKENING COLD FRONT WILL REACH W WA ON
THURSDAY. THIS WOULD BE THE SYSTEM CURRENTLY FAR OFFSHORE NEAR 170W.
THIS SYSTEM COULD BRING A LITTLE MORE WIDESPREAD PRECIP THAN
TUESDAYS SYSTEM...BUT STILL ON THE LIGHT SIDE. KAM

.LONG TERM...MODELS AGREE THAT A WEAK UPPER LEVEL TROUGH WILL MOVE
ACROSS THE AREA FRIDAY...FOLLOWED BY A WEAK RIDGE FRIDAY NIGHT.
SCATTERED SHOWERS ASSOCIATED WITH THE TROUGH SHOULD DIMINISH FRIDAY
NIGHT.

A LARGE COLD UPPER LEVEL LONGWAVE LOW WILL SET UP OVER THE NE
PACIFIC THIS WEEKEND WITH STRONG FLOW ALOFT AROUND THE LOW. MOIST
WSW FLOW ALOFT OVER THE NE PACIFIC E OF THE LOW WILL BE AIMED AT THE
PACNW. THIS LOOKS LIKE POTENTIALLY THE WETTEST PERIOD FOR W WA SINCE
MID MARCH. KAM

&&

.AVIATION...THE UPPER LEVEL RIDGE OVER THE REGION WILL WEAKEN AS THE
RIDGE AXIS SHIFTS EAST OF THE CASCADES OVERNIGHT. A WEAK COLD FRONT
IS ON TRACK TO MOVE THROUGH THE FORECAST AREA TUESDAY
AFTERNOON...FOLLOWED BY AN UPPER LEVEL TROUGH TUESDAY NIGHT. THIS
WILL RESULT IN A SHORT PERIOD OF RAIN FOLLOWED BY SHOWERS TUESDAY
NIGHT. NORTHWEST FLOW ALOFT WILL BECOME SOUTHWEST LATE TONIGHT AS
THE UPPER LEVEL TROUGH APPROACHES FROM THE WEST. THE AIR MASS WILL
BECOME MOIST LATE TONIGHT AND TUESDAY AS LOW LEVEL ONSHORE FLOW
INCREASES.

MARINE STRATUS ALONG THE COAST WILL DEEPEN AND PUSH INLAND TONIGHT.
THE PUSH CONTINUES TO LOOK WEAK...THE CURRENT FORECAST REFLECTS
STRATUS REACHING OLYMPIA LATE TONIGHT WITH ANY LOW CLOUDS REACHING
THE CENTRAL SOUND REMAINING THIN AND RELATIVELY SHORT LIVED TUESDAY
MORNING.

KSEA...NORTH WIND TO 10 KT...BECOMING SOUTHERLY TO 8 KT LATE...THEN
SOUTHWEST 6-12 KT TUESDAY AFTERNOON. THIN MARINE STRATUS WILL LIKELY
REACH THE TERMINAL AROUND 13Z WITH SEVERAL HOURS OF SCT-BKN005
TUESDAY MORNING.

&&

.MARINE...ONSHORE FLOW WILL STRENGTHEN TONIGHT AS LOW PRESSURE OVER
WESTERN WASHINGTON MOVES EAST OF THE CASCADES. SMALL CRAFT ADVISORY
WINDS REMAIN FORECAST FOR THE COASTAL WATERS...WESTERN AND CENTRAL
STRAIT OF JUAN DE FUCA...ADMIRALTY INLET...AND NORTHERN INLAND
WATERS. THE STRONGEST WINDS SHOULD OCCUR IN THE CENTRAL AND EASTERN
STRAIT.

ONSHORE FLOW WILL CONTINUE TO INCREASE TUESDAY AND TUESDAY NIGHT AS
A WEAK COLD FRONT MOVES INLAND. GALE WESTERLIES REMAIN LIKELY FOR
THE CENTRAL AND EASTERN STRAIT. A GALE WATCH REMAINS IN PLACE FOR
THE POTENTIAL FOR MARGINAL GALES OVER THE NORTHWEST COASTAL WATERS.
SMALL CRAFT ADVISORY WINDS WILL CONTINUE FOR ALL OTHER MARINE ZONES
EXCEPT PUGET SOUND AND HOOD CANAL.

A SECOND WEAK COLD FRONT WILL CROSS THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT...WITH A STRONGER FRONTAL SYSTEM EXPECTED TO REACH
THE AREA SATURDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY COASTAL WATERS...CENTRAL AND EASTERN
       STRAIT OF JUAN DE FUCA...ADMIRALTY INLET...NORTHERN INLAND
       WATERS.
    .GALE WARNING FOR TUESDAY NIGHT CENTRAL AND EASTERN STRAIT.
    .GALE WATCH FOR TUESDAY NIGHT COASTAL WATERS ZONES 150 170 173.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML










000
FXUS66 KSEW 210346
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
846 PM PDT MON APR 20 2015

.SYNOPSIS...AN UPPER LEVEL RIDGE WILL KEEPS SKIES MOSTLY CLEAR
TONIGHT. WEAK LOW LEVEL ONSHORE FLOW OVERNIGHT WILL ALLOW A FEW
AREAS OF LOW CLOUDS TO FORM OVER WESTERN WASHINGTON TUESDAY MORNING.
A WEAK FRONT WILL BRING CLOUDS AND A FEW SHOWERS TO THE COAST LATE
TUESDAY MORNING AND THEN OVER PUGET SOUND LATE IN THE DAY. AN UPPER
LEVEL TROUGH WILL FOLLOW TUESDAY NIGHT AND WEDNESDAY MORNING.
ANOTHER WEAK FRONT WILL BRING A FEW SHOWERS ON THURSDAY. MOIST
SOUTHWEST FLOW ALOFT WILL BRING PERIODS OF RAIN NEXT WEEKEND.

&&

.SHORT TERM...THE UPPER LEVEL RIDGE OVER W WA THIS EVENING WILL
SHIFT OVER N ID TUESDAY MORNING...ALLOWING THE WEAK FRONT JUST
OFFSHORE NEAR 130W TO MOVE TOWARD THE WA COAST. ONSHORE FLOW IS
INCREASING THIS EVENING AHEAD OF THE FRONT...WHICH IS VERY
REMINISCENT OF A SUMMER-TIME PATTERN. THERE WAS JUST A LITTLE RIBBON
OF STRATUS ALONG THE CENTRAL COASTLINE LATE THIS AFTERNOON AND
ONSHORE PRESSURE GRADIENTS HAVE ONLY MADE IT UP TO 1.0 TO 1.5
MB...SO IT DOES NOT LOOK LIKE THERE WILL BE A WHOLE LOT OF STRATUS
FORMING IN PLACE OVER THE INTERIOR TUESDAY MORNING. BEST GUESS IS
AREAS OF STRATUS THROUGH THE STRAIT AND OVER THE LOWER CHEHALIS
VALLEY MAINLY W OF SHELTON.

THE WEAK FRONT ALONG 130W THIS EVENING WILL REACH THE AREA ON
TUESDAY. MODELS HAVE THE LEADING EDGE OF THE FRONTAL CLOUDS REACHING
THE COAST AROUND LATE TUESDAY MORNING...AND PUGET SOUND LATE IN THE
AFTERNOON. THE FRONT SHOULD BE OVER THE CASCADES BY LATE EVENING.
FRONTAL PRECIPITATION WILL BE PRETTY SKIMPY...WITH LIGHT
ACCUMULATIONS ON THE COAST MAINLY UPSTREAM OF THE OLYMPICS. OVER THE
INTERIOR IT LOOKS LIKE MOST OF THE PRECIP WILL BE AROUND CENTRAL
PUGET SOUND WHERE A CONVERGENCE ZONE IS EXPECTED TO FORM...AND OVER
THE CASCADES WHERE LOW LEVEL W WINDS WILL GENERATE UPSLOPE FLOW.

AN UPPER LEVEL TROUGH WILL BE RIGHT BEHIND THE FRONT...CROSSING
PUGET SOUND EARLY WEDNESDAY MORNING...THEN MOVING OVER E WA
WEDNESDAY AFTERNOON. NAM HIGH RES SOUNDINGS INDICATE THE AIR MASS
WILL REMAIN STABLE WITH BOTH THE WEAK FRONT AND THE ASSOCIATED UPPER
LEVEL TROUGH. PRECIP ON WEDNESDAY BEHIND THE UPPER TROUGH SHOULD BE
MAINLY ASSOCIATED WITH THE CONVERGENCE ZONE...AND THOSE SHOWERS
SHOULD BE DIMINISHING BY AFTERNOON.

IT LOOKS LIKE WEDNESDAY AFTERNOON AND EVENING WILL BE MOSTLY DRY. A
SMALL WEAK UPPER LEVEL SHORTWAVE RIDGE WILL MOVE ACROSS THE
AREA...BUT THE BREAK WILL BE MOSTLY DUE TO THE GAP IN-BETWEEN
WEATHER SYSTEMS.

GFS AND ECMWF AGREE THAT A WEAKENING COLD FRONT WILL REACH W WA ON
THURSDAY. THIS WOULD BE THE SYSTEM CURRENTLY FAR OFFSHORE NEAR 170W.
THIS SYSTEM COULD BRING A LITTLE MORE WIDESPREAD PRECIP THAN
TUESDAYS SYSTEM...BUT STILL ON THE LIGHT SIDE. KAM

.LONG TERM...MODELS AGREE THAT A WEAK UPPER LEVEL TROUGH WILL MOVE
ACROSS THE AREA FRIDAY...FOLLOWED BY A WEAK RIDGE FRIDAY NIGHT.
SCATTERED SHOWERS ASSOCIATED WITH THE TROUGH SHOULD DIMINISH FRIDAY
NIGHT.

A LARGE COLD UPPER LEVEL LONGWAVE LOW WILL SET UP OVER THE NE
PACIFIC THIS WEEKEND WITH STRONG FLOW ALOFT AROUND THE LOW. MOIST
WSW FLOW ALOFT OVER THE NE PACIFIC E OF THE LOW WILL BE AIMED AT THE
PACNW. THIS LOOKS LIKE POTENTIALLY THE WETTEST PERIOD FOR W WA SINCE
MID MARCH. KAM

&&

.AVIATION...THE UPPER LEVEL RIDGE OVER THE REGION WILL WEAKEN AS THE
RIDGE AXIS SHIFTS EAST OF THE CASCADES OVERNIGHT. A WEAK COLD FRONT
IS ON TRACK TO MOVE THROUGH THE FORECAST AREA TUESDAY
AFTERNOON...FOLLOWED BY AN UPPER LEVEL TROUGH TUESDAY NIGHT. THIS
WILL RESULT IN A SHORT PERIOD OF RAIN FOLLOWED BY SHOWERS TUESDAY
NIGHT. NORTHWEST FLOW ALOFT WILL BECOME SOUTHWEST LATE TONIGHT AS
THE UPPER LEVEL TROUGH APPROACHES FROM THE WEST. THE AIR MASS WILL
BECOME MOIST LATE TONIGHT AND TUESDAY AS LOW LEVEL ONSHORE FLOW
INCREASES.

MARINE STRATUS ALONG THE COAST WILL DEEPEN AND PUSH INLAND TONIGHT.
THE PUSH CONTINUES TO LOOK WEAK...THE CURRENT FORECAST REFLECTS
STRATUS REACHING OLYMPIA LATE TONIGHT WITH ANY LOW CLOUDS REACHING
THE CENTRAL SOUND REMAINING THIN AND RELATIVELY SHORT LIVED TUESDAY
MORNING.

KSEA...NORTH WIND TO 10 KT...BECOMING SOUTHERLY TO 8 KT LATE...THEN
SOUTHWEST 6-12 KT TUESDAY AFTERNOON. THIN MARINE STRATUS WILL LIKELY
REACH THE TERMINAL AROUND 13Z WITH SEVERAL HOURS OF SCT-BKN005
TUESDAY MORNING.

&&

.MARINE...ONSHORE FLOW WILL STRENGTHEN TONIGHT AS LOW PRESSURE OVER
WESTERN WASHINGTON MOVES EAST OF THE CASCADES. SMALL CRAFT ADVISORY
WINDS REMAIN FORECAST FOR THE COASTAL WATERS...WESTERN AND CENTRAL
STRAIT OF JUAN DE FUCA...ADMIRALTY INLET...AND NORTHERN INLAND
WATERS. THE STRONGEST WINDS SHOULD OCCUR IN THE CENTRAL AND EASTERN
STRAIT.

ONSHORE FLOW WILL CONTINUE TO INCREASE TUESDAY AND TUESDAY NIGHT AS
A WEAK COLD FRONT MOVES INLAND. GALE WESTERLIES REMAIN LIKELY FOR
THE CENTRAL AND EASTERN STRAIT. A GALE WATCH REMAINS IN PLACE FOR
THE POTENTIAL FOR MARGINAL GALES OVER THE NORTHWEST COASTAL WATERS.
SMALL CRAFT ADVISORY WINDS WILL CONTINUE FOR ALL OTHER MARINE ZONES
EXCEPT PUGET SOUND AND HOOD CANAL.

A SECOND WEAK COLD FRONT WILL CROSS THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT...WITH A STRONGER FRONTAL SYSTEM EXPECTED TO REACH
THE AREA SATURDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY COASTAL WATERS...CENTRAL AND EASTERN
       STRAIT OF JUAN DE FUCA...ADMIRALTY INLET...NORTHERN INLAND
       WATERS.
    .GALE WARNING FOR TUESDAY NIGHT CENTRAL AND EASTERN STRAIT.
    .GALE WATCH FOR TUESDAY NIGHT COASTAL WATERS ZONES 150 170 173.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML










000
FXUS66 KSEW 210346
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
846 PM PDT MON APR 20 2015

.SYNOPSIS...AN UPPER LEVEL RIDGE WILL KEEPS SKIES MOSTLY CLEAR
TONIGHT. WEAK LOW LEVEL ONSHORE FLOW OVERNIGHT WILL ALLOW A FEW
AREAS OF LOW CLOUDS TO FORM OVER WESTERN WASHINGTON TUESDAY MORNING.
A WEAK FRONT WILL BRING CLOUDS AND A FEW SHOWERS TO THE COAST LATE
TUESDAY MORNING AND THEN OVER PUGET SOUND LATE IN THE DAY. AN UPPER
LEVEL TROUGH WILL FOLLOW TUESDAY NIGHT AND WEDNESDAY MORNING.
ANOTHER WEAK FRONT WILL BRING A FEW SHOWERS ON THURSDAY. MOIST
SOUTHWEST FLOW ALOFT WILL BRING PERIODS OF RAIN NEXT WEEKEND.

&&

.SHORT TERM...THE UPPER LEVEL RIDGE OVER W WA THIS EVENING WILL
SHIFT OVER N ID TUESDAY MORNING...ALLOWING THE WEAK FRONT JUST
OFFSHORE NEAR 130W TO MOVE TOWARD THE WA COAST. ONSHORE FLOW IS
INCREASING THIS EVENING AHEAD OF THE FRONT...WHICH IS VERY
REMINISCENT OF A SUMMER-TIME PATTERN. THERE WAS JUST A LITTLE RIBBON
OF STRATUS ALONG THE CENTRAL COASTLINE LATE THIS AFTERNOON AND
ONSHORE PRESSURE GRADIENTS HAVE ONLY MADE IT UP TO 1.0 TO 1.5
MB...SO IT DOES NOT LOOK LIKE THERE WILL BE A WHOLE LOT OF STRATUS
FORMING IN PLACE OVER THE INTERIOR TUESDAY MORNING. BEST GUESS IS
AREAS OF STRATUS THROUGH THE STRAIT AND OVER THE LOWER CHEHALIS
VALLEY MAINLY W OF SHELTON.

THE WEAK FRONT ALONG 130W THIS EVENING WILL REACH THE AREA ON
TUESDAY. MODELS HAVE THE LEADING EDGE OF THE FRONTAL CLOUDS REACHING
THE COAST AROUND LATE TUESDAY MORNING...AND PUGET SOUND LATE IN THE
AFTERNOON. THE FRONT SHOULD BE OVER THE CASCADES BY LATE EVENING.
FRONTAL PRECIPITATION WILL BE PRETTY SKIMPY...WITH LIGHT
ACCUMULATIONS ON THE COAST MAINLY UPSTREAM OF THE OLYMPICS. OVER THE
INTERIOR IT LOOKS LIKE MOST OF THE PRECIP WILL BE AROUND CENTRAL
PUGET SOUND WHERE A CONVERGENCE ZONE IS EXPECTED TO FORM...AND OVER
THE CASCADES WHERE LOW LEVEL W WINDS WILL GENERATE UPSLOPE FLOW.

AN UPPER LEVEL TROUGH WILL BE RIGHT BEHIND THE FRONT...CROSSING
PUGET SOUND EARLY WEDNESDAY MORNING...THEN MOVING OVER E WA
WEDNESDAY AFTERNOON. NAM HIGH RES SOUNDINGS INDICATE THE AIR MASS
WILL REMAIN STABLE WITH BOTH THE WEAK FRONT AND THE ASSOCIATED UPPER
LEVEL TROUGH. PRECIP ON WEDNESDAY BEHIND THE UPPER TROUGH SHOULD BE
MAINLY ASSOCIATED WITH THE CONVERGENCE ZONE...AND THOSE SHOWERS
SHOULD BE DIMINISHING BY AFTERNOON.

IT LOOKS LIKE WEDNESDAY AFTERNOON AND EVENING WILL BE MOSTLY DRY. A
SMALL WEAK UPPER LEVEL SHORTWAVE RIDGE WILL MOVE ACROSS THE
AREA...BUT THE BREAK WILL BE MOSTLY DUE TO THE GAP IN-BETWEEN
WEATHER SYSTEMS.

GFS AND ECMWF AGREE THAT A WEAKENING COLD FRONT WILL REACH W WA ON
THURSDAY. THIS WOULD BE THE SYSTEM CURRENTLY FAR OFFSHORE NEAR 170W.
THIS SYSTEM COULD BRING A LITTLE MORE WIDESPREAD PRECIP THAN
TUESDAYS SYSTEM...BUT STILL ON THE LIGHT SIDE. KAM

.LONG TERM...MODELS AGREE THAT A WEAK UPPER LEVEL TROUGH WILL MOVE
ACROSS THE AREA FRIDAY...FOLLOWED BY A WEAK RIDGE FRIDAY NIGHT.
SCATTERED SHOWERS ASSOCIATED WITH THE TROUGH SHOULD DIMINISH FRIDAY
NIGHT.

A LARGE COLD UPPER LEVEL LONGWAVE LOW WILL SET UP OVER THE NE
PACIFIC THIS WEEKEND WITH STRONG FLOW ALOFT AROUND THE LOW. MOIST
WSW FLOW ALOFT OVER THE NE PACIFIC E OF THE LOW WILL BE AIMED AT THE
PACNW. THIS LOOKS LIKE POTENTIALLY THE WETTEST PERIOD FOR W WA SINCE
MID MARCH. KAM

&&

.AVIATION...THE UPPER LEVEL RIDGE OVER THE REGION WILL WEAKEN AS THE
RIDGE AXIS SHIFTS EAST OF THE CASCADES OVERNIGHT. A WEAK COLD FRONT
IS ON TRACK TO MOVE THROUGH THE FORECAST AREA TUESDAY
AFTERNOON...FOLLOWED BY AN UPPER LEVEL TROUGH TUESDAY NIGHT. THIS
WILL RESULT IN A SHORT PERIOD OF RAIN FOLLOWED BY SHOWERS TUESDAY
NIGHT. NORTHWEST FLOW ALOFT WILL BECOME SOUTHWEST LATE TONIGHT AS
THE UPPER LEVEL TROUGH APPROACHES FROM THE WEST. THE AIR MASS WILL
BECOME MOIST LATE TONIGHT AND TUESDAY AS LOW LEVEL ONSHORE FLOW
INCREASES.

MARINE STRATUS ALONG THE COAST WILL DEEPEN AND PUSH INLAND TONIGHT.
THE PUSH CONTINUES TO LOOK WEAK...THE CURRENT FORECAST REFLECTS
STRATUS REACHING OLYMPIA LATE TONIGHT WITH ANY LOW CLOUDS REACHING
THE CENTRAL SOUND REMAINING THIN AND RELATIVELY SHORT LIVED TUESDAY
MORNING.

KSEA...NORTH WIND TO 10 KT...BECOMING SOUTHERLY TO 8 KT LATE...THEN
SOUTHWEST 6-12 KT TUESDAY AFTERNOON. THIN MARINE STRATUS WILL LIKELY
REACH THE TERMINAL AROUND 13Z WITH SEVERAL HOURS OF SCT-BKN005
TUESDAY MORNING.

&&

.MARINE...ONSHORE FLOW WILL STRENGTHEN TONIGHT AS LOW PRESSURE OVER
WESTERN WASHINGTON MOVES EAST OF THE CASCADES. SMALL CRAFT ADVISORY
WINDS REMAIN FORECAST FOR THE COASTAL WATERS...WESTERN AND CENTRAL
STRAIT OF JUAN DE FUCA...ADMIRALTY INLET...AND NORTHERN INLAND
WATERS. THE STRONGEST WINDS SHOULD OCCUR IN THE CENTRAL AND EASTERN
STRAIT.

ONSHORE FLOW WILL CONTINUE TO INCREASE TUESDAY AND TUESDAY NIGHT AS
A WEAK COLD FRONT MOVES INLAND. GALE WESTERLIES REMAIN LIKELY FOR
THE CENTRAL AND EASTERN STRAIT. A GALE WATCH REMAINS IN PLACE FOR
THE POTENTIAL FOR MARGINAL GALES OVER THE NORTHWEST COASTAL WATERS.
SMALL CRAFT ADVISORY WINDS WILL CONTINUE FOR ALL OTHER MARINE ZONES
EXCEPT PUGET SOUND AND HOOD CANAL.

A SECOND WEAK COLD FRONT WILL CROSS THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT...WITH A STRONGER FRONTAL SYSTEM EXPECTED TO REACH
THE AREA SATURDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY COASTAL WATERS...CENTRAL AND EASTERN
       STRAIT OF JUAN DE FUCA...ADMIRALTY INLET...NORTHERN INLAND
       WATERS.
    .GALE WARNING FOR TUESDAY NIGHT CENTRAL AND EASTERN STRAIT.
    .GALE WATCH FOR TUESDAY NIGHT COASTAL WATERS ZONES 150 170 173.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML










000
FXUS66 KSEW 210346
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
846 PM PDT MON APR 20 2015

.SYNOPSIS...AN UPPER LEVEL RIDGE WILL KEEPS SKIES MOSTLY CLEAR
TONIGHT. WEAK LOW LEVEL ONSHORE FLOW OVERNIGHT WILL ALLOW A FEW
AREAS OF LOW CLOUDS TO FORM OVER WESTERN WASHINGTON TUESDAY MORNING.
A WEAK FRONT WILL BRING CLOUDS AND A FEW SHOWERS TO THE COAST LATE
TUESDAY MORNING AND THEN OVER PUGET SOUND LATE IN THE DAY. AN UPPER
LEVEL TROUGH WILL FOLLOW TUESDAY NIGHT AND WEDNESDAY MORNING.
ANOTHER WEAK FRONT WILL BRING A FEW SHOWERS ON THURSDAY. MOIST
SOUTHWEST FLOW ALOFT WILL BRING PERIODS OF RAIN NEXT WEEKEND.

&&

.SHORT TERM...THE UPPER LEVEL RIDGE OVER W WA THIS EVENING WILL
SHIFT OVER N ID TUESDAY MORNING...ALLOWING THE WEAK FRONT JUST
OFFSHORE NEAR 130W TO MOVE TOWARD THE WA COAST. ONSHORE FLOW IS
INCREASING THIS EVENING AHEAD OF THE FRONT...WHICH IS VERY
REMINISCENT OF A SUMMER-TIME PATTERN. THERE WAS JUST A LITTLE RIBBON
OF STRATUS ALONG THE CENTRAL COASTLINE LATE THIS AFTERNOON AND
ONSHORE PRESSURE GRADIENTS HAVE ONLY MADE IT UP TO 1.0 TO 1.5
MB...SO IT DOES NOT LOOK LIKE THERE WILL BE A WHOLE LOT OF STRATUS
FORMING IN PLACE OVER THE INTERIOR TUESDAY MORNING. BEST GUESS IS
AREAS OF STRATUS THROUGH THE STRAIT AND OVER THE LOWER CHEHALIS
VALLEY MAINLY W OF SHELTON.

THE WEAK FRONT ALONG 130W THIS EVENING WILL REACH THE AREA ON
TUESDAY. MODELS HAVE THE LEADING EDGE OF THE FRONTAL CLOUDS REACHING
THE COAST AROUND LATE TUESDAY MORNING...AND PUGET SOUND LATE IN THE
AFTERNOON. THE FRONT SHOULD BE OVER THE CASCADES BY LATE EVENING.
FRONTAL PRECIPITATION WILL BE PRETTY SKIMPY...WITH LIGHT
ACCUMULATIONS ON THE COAST MAINLY UPSTREAM OF THE OLYMPICS. OVER THE
INTERIOR IT LOOKS LIKE MOST OF THE PRECIP WILL BE AROUND CENTRAL
PUGET SOUND WHERE A CONVERGENCE ZONE IS EXPECTED TO FORM...AND OVER
THE CASCADES WHERE LOW LEVEL W WINDS WILL GENERATE UPSLOPE FLOW.

AN UPPER LEVEL TROUGH WILL BE RIGHT BEHIND THE FRONT...CROSSING
PUGET SOUND EARLY WEDNESDAY MORNING...THEN MOVING OVER E WA
WEDNESDAY AFTERNOON. NAM HIGH RES SOUNDINGS INDICATE THE AIR MASS
WILL REMAIN STABLE WITH BOTH THE WEAK FRONT AND THE ASSOCIATED UPPER
LEVEL TROUGH. PRECIP ON WEDNESDAY BEHIND THE UPPER TROUGH SHOULD BE
MAINLY ASSOCIATED WITH THE CONVERGENCE ZONE...AND THOSE SHOWERS
SHOULD BE DIMINISHING BY AFTERNOON.

IT LOOKS LIKE WEDNESDAY AFTERNOON AND EVENING WILL BE MOSTLY DRY. A
SMALL WEAK UPPER LEVEL SHORTWAVE RIDGE WILL MOVE ACROSS THE
AREA...BUT THE BREAK WILL BE MOSTLY DUE TO THE GAP IN-BETWEEN
WEATHER SYSTEMS.

GFS AND ECMWF AGREE THAT A WEAKENING COLD FRONT WILL REACH W WA ON
THURSDAY. THIS WOULD BE THE SYSTEM CURRENTLY FAR OFFSHORE NEAR 170W.
THIS SYSTEM COULD BRING A LITTLE MORE WIDESPREAD PRECIP THAN
TUESDAYS SYSTEM...BUT STILL ON THE LIGHT SIDE. KAM

.LONG TERM...MODELS AGREE THAT A WEAK UPPER LEVEL TROUGH WILL MOVE
ACROSS THE AREA FRIDAY...FOLLOWED BY A WEAK RIDGE FRIDAY NIGHT.
SCATTERED SHOWERS ASSOCIATED WITH THE TROUGH SHOULD DIMINISH FRIDAY
NIGHT.

A LARGE COLD UPPER LEVEL LONGWAVE LOW WILL SET UP OVER THE NE
PACIFIC THIS WEEKEND WITH STRONG FLOW ALOFT AROUND THE LOW. MOIST
WSW FLOW ALOFT OVER THE NE PACIFIC E OF THE LOW WILL BE AIMED AT THE
PACNW. THIS LOOKS LIKE POTENTIALLY THE WETTEST PERIOD FOR W WA SINCE
MID MARCH. KAM

&&

.AVIATION...THE UPPER LEVEL RIDGE OVER THE REGION WILL WEAKEN AS THE
RIDGE AXIS SHIFTS EAST OF THE CASCADES OVERNIGHT. A WEAK COLD FRONT
IS ON TRACK TO MOVE THROUGH THE FORECAST AREA TUESDAY
AFTERNOON...FOLLOWED BY AN UPPER LEVEL TROUGH TUESDAY NIGHT. THIS
WILL RESULT IN A SHORT PERIOD OF RAIN FOLLOWED BY SHOWERS TUESDAY
NIGHT. NORTHWEST FLOW ALOFT WILL BECOME SOUTHWEST LATE TONIGHT AS
THE UPPER LEVEL TROUGH APPROACHES FROM THE WEST. THE AIR MASS WILL
BECOME MOIST LATE TONIGHT AND TUESDAY AS LOW LEVEL ONSHORE FLOW
INCREASES.

MARINE STRATUS ALONG THE COAST WILL DEEPEN AND PUSH INLAND TONIGHT.
THE PUSH CONTINUES TO LOOK WEAK...THE CURRENT FORECAST REFLECTS
STRATUS REACHING OLYMPIA LATE TONIGHT WITH ANY LOW CLOUDS REACHING
THE CENTRAL SOUND REMAINING THIN AND RELATIVELY SHORT LIVED TUESDAY
MORNING.

KSEA...NORTH WIND TO 10 KT...BECOMING SOUTHERLY TO 8 KT LATE...THEN
SOUTHWEST 6-12 KT TUESDAY AFTERNOON. THIN MARINE STRATUS WILL LIKELY
REACH THE TERMINAL AROUND 13Z WITH SEVERAL HOURS OF SCT-BKN005
TUESDAY MORNING.

&&

.MARINE...ONSHORE FLOW WILL STRENGTHEN TONIGHT AS LOW PRESSURE OVER
WESTERN WASHINGTON MOVES EAST OF THE CASCADES. SMALL CRAFT ADVISORY
WINDS REMAIN FORECAST FOR THE COASTAL WATERS...WESTERN AND CENTRAL
STRAIT OF JUAN DE FUCA...ADMIRALTY INLET...AND NORTHERN INLAND
WATERS. THE STRONGEST WINDS SHOULD OCCUR IN THE CENTRAL AND EASTERN
STRAIT.

ONSHORE FLOW WILL CONTINUE TO INCREASE TUESDAY AND TUESDAY NIGHT AS
A WEAK COLD FRONT MOVES INLAND. GALE WESTERLIES REMAIN LIKELY FOR
THE CENTRAL AND EASTERN STRAIT. A GALE WATCH REMAINS IN PLACE FOR
THE POTENTIAL FOR MARGINAL GALES OVER THE NORTHWEST COASTAL WATERS.
SMALL CRAFT ADVISORY WINDS WILL CONTINUE FOR ALL OTHER MARINE ZONES
EXCEPT PUGET SOUND AND HOOD CANAL.

A SECOND WEAK COLD FRONT WILL CROSS THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT...WITH A STRONGER FRONTAL SYSTEM EXPECTED TO REACH
THE AREA SATURDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY COASTAL WATERS...CENTRAL AND EASTERN
       STRAIT OF JUAN DE FUCA...ADMIRALTY INLET...NORTHERN INLAND
       WATERS.
    .GALE WARNING FOR TUESDAY NIGHT CENTRAL AND EASTERN STRAIT.
    .GALE WATCH FOR TUESDAY NIGHT COASTAL WATERS ZONES 150 170 173.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML










000
FXUS66 KPQR 210320 AAA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
820 PM PDT MON APR 20 2015

.SYNOPSIS...INCREASING ONSHORE FLOW WILL RESULT IN COOLER CONDITIONS
TUESDAY AND THEN CONTINUING FOR THE REMAINDER OF THE WEEK. DAYTIME
TEMPERATURES WILL FALL TO NEAR AVERAGE VALUES. A WEAK FRONTAL SYSTEM
WILL MOVE ACROSS THE AREA TUESDAY NIGHT...WHICH WILL REINFORCE THE
MARINE LAYER. A WETTER PATTERN LOOKS TO DEVELOP LATE SATURDAY AND
SUNDAY...WITH PERHAPS ANOTHER ROUND OF WET WEATHER EARLY NEXT WEEK.

&&

.SHORT TERM...00Z LOCAL SURFACE ANALYSIS SHOWED THE THERMALLY-INDUCED
SURFACE TROUGH ALONG THE EAST SLOPES OF THE WASHINGTON CASCADES...
THROUGH THE CENTRAL COLUMBIA GORGE AND EXTENDING ALONG THE OREGON
CASCADE FOOTHILLS. AS EXPECTED...THE 00Z MON NAM WAS TOO FAST MOVING
THE THERMAL TROUGH EAST. LAST AVAILABLE VISIBLE SATELLITE IMAGES
SHOWED A FAIRLY SHALLOW MARINE LAYER ALONG THE OREGON COASTAL
STRIP...BUT STARTING TO PUSH INTO THE DOUGLAS COUNTY COASTAL VALLEYS.
THE 12Z HI RES ARW MODEL LOOKS TO DEPICT THE MARINE LAYER RATHER
WELL. AT 03Z THE MODEL SHOWS 90 PCT OR GREATER BOUNDARY LAYER
MOISTURE STARTING TO PUSH INTO THE CENTRAL COASTAL VALLEYS. ANOTHER
SIGN OF INCREASING ONSHORE FLOW IS THE S-SW WIND AT KMMV. AT 02Z THE
TEMP HAD DROPPED TO 69...WHILE THE KPDX METRO AREA WAS STILL IN THE
MID TO UPPER 70S. TYPICALLY...WITH A SW MARINE SURGE...THE SRN
WILLAMETTE VALLEY PICKS UP A SW BREEZE DURING THE EVENING. AS OF 02Z
KEUG WAS SHOWING CALM CONDITIONS. HOWEVER...AT 03Z KSLE AND KUAO
OBSERVED SW-W WIND UP TO 11 KT. THE HI RES ARW STILL HINTS AT A SW
MARINE SURGE THROUGH THE LANE COUNTY COASTAL GAPS OVERNIGHT. IT ALSO
DEPICTS ANOTHER INTRUSION DOWN THE COLUMBIA RIVER. EXPECT KKLS TO
BECOME OVERCAST LATE TONIGHT OR AROUND SUNRISE TUE.

850 MB TEMPS FALL FROM 12.2C TODAY (00Z KSLE SOUNDING) TO 3-4C BY 00Z
WED. MODELS SHOWING A TIGHT 850 MB TEMP GRADIENT FROM THE CASCADE
CREST TO THE WILLAMETTE VALLEY AND CLARK COUNTY IN SW WA 18Z TUE. THE
MAIN RESULT...OTHER THAN SIGNIFICANT COOLING...WILL BE INCREASED
WIND...ESPECIALLY EAST OF KCZK AND THROUGH COAST RANGE GAPS. SHALLOW
INSTABILITY AND MOISTURE MAY PRODUCE A FEW VERY LIGHT SHOWERS TUESDAY
NIGHT INTO EARLY WEDNESDAY...PARTICULARLY ACROSS THE NORTH AND IN THE
UPSLOPE AREAS...BUT CONFIDENCE IS LOW. NAM...GFS AND ECMWF SURFACE
PATTERN WED AFTERNOON SUGGEST IT COULD END UP PARTLY CLOUDY ACROSS
THE S HALF AS ALL AFOREMENTIONED MODELS HAVE A N-NE SURFACE ISOBAR
CONFIGURATION. WOULD EXPECT LIMITED CLEARING OVER THE N...ESPECIALLY
THE SW WA ZONES CLOSEST TO THE PASSING UPER TROUGH. ANOTHER WEAKENING
FRONT MAY BRING INCREASING PRECIP CHANCES TO THE FAR NORTHWEST ZONES
ON THURSDAY. ALL IN ALL...MOST LOCATIONS LOOK TO REMAIN GENERALLY DRY
THE NEXT FEW DAYS WITH TEMPERATURES TOPPING OUT NEAR AVERAGE.
WEISHAAR

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO
STRUGGLE ON THE DETAILS...BUT SUGGEST ONSHORE FLOW WILL CONTINUE NEAR
AVERAGE TEMPERATURES WITH A CHANCE FOR SOME LIGHT SHOWERS THURSDAY
NIGHT AND FRIDAY. WHILE MODELS DIFFER ON TIMING...BUT THE GFS AND EC
SUGGEST A WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD
ACROSS THE AREA LATE SATURDAY THROUGH SUNDAY NIGHT. AS A
RESULT...POPS WERE INCREASED IN THE LIKELY TO CATEGORICAL RANGE FOR
THE PRIME WINDOW OF SATURDAY NIGHT AND SUNDAY. BOTH MODELS SUGGEST
ANOTHER STORM SYSTEM IS LIKELY NEXT WEEK...BUT ONCE AGAIN DIFFER ON
TIMING SO POPS WERE TRENDED MORE INTO THE HIGH END CHANCE TO LOW END
LIKELY RANGE. /NEUMAN

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES THROUGH THIS EVENING. THE
FLOW PATTERN WILL CONTINUE TO TURN ONSHORE THIS AFTERNOON AS A
WEAK FRONT APPROACHES THE REGION ALLOWING MARINE STRATUS TO FILL
BACK IN ALONG THE COAST - EXPECT IFR CIGS BETWEEN 500 AND 1000 FT
AND REDUCED VSBY THROUGH LATE TUE MORNING. LOW CLOUDS WILL
CONTINUE TO PUSH INLAND TONIGHT...WITH INTERIOR SITES LIKELY
SEEING MVFR CIGS BETWEEN 1500 AND 2000 FT BY 15Z. CONDITIONS TURN
VFR UNDER MOSTLY CLOUDY SKIES TUE AFTERNOON.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
LOWER CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AROUND 2000 FT
AFFECTING THE TERMINAL BY 14Z. VFR RETURNS BY AROUND 18Z TUESDAY
WITH NW WINDS PICKING UP MID AFTERNOON.

&&

.MARINE...INCREASED FORECAST WINDS SLIGHTLY OVER THE NEXT 24
HOURS TO NUDGE CLOSER TO OBS AS WELL AS RUC. BUOY 29 HAS BEEN
GUSTING TO AROUND 20 KT FOR A FEW HOURS BUT SINCE WINDS ARE
INCREDIBLY MARGINAL AND PROBABLY OVER JUST A SMALL AREA...WILL
NOT MOVE UP THE BEGINNING OF THE SMALL CRAFT ADVISORY FOR WINDS. WILL
HAVE A LAST VERY STRONG EBB ON THE COLUMBIA BAR TUESDAY
MORNING...SO ISSUED A SMALL CRAFT ADVISORY FOR ROUGH BAR DURING
THE MORNING EBB AND THEN AGAIN FOR THE TUESDAY EVENING EBB WITH
INCREASE IN SWELL AND WINDS. BOWEN

PREVIOUS DISCUSSION...A WEAK FRONT WILL MOVE ACROSS THE WATERS
TOMORROW MORNING BRINGING GUSTY NORTHWESTERLY WINDS AND BUILDING
SEAS. EXPECT GUSTS TO 30 KT AND SEAS AROUND 11 FT FROM TUE
MORNING TO WED. HIGH PRES BRIEFLY RETURNS WED AFTERNOON BEFORE
ANOTHER WEAK FRONT MOVES ACROSS THE WATERS ON THU. NOT EXPECTING
MUCH IN THE WAY OF IMPACTS WITH THIS SECOND FRONT. A MUCH STRONGER
FRONT LOOKS TO MOVE ACROSS THE WATERS OVER THE WEEKEND AND WILL
LIKELY BRING GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING
SEAS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM TUESDAY TO NOON PDT
     WEDNESDAY FOR WATERS FROM CAPE SHOALWATER WA TO CASCADE
     HEAD OR FROM 10 TO 60 NM-WATERS FROM CASCADE HEAD TO
     FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM TUESDAY TO 6
     PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM TUESDAY TO NOON PDT
     WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     CASCADE HEAD OR OUT 10 NM-COASTAL WATERS FROM CASCADE HEAD
     TO FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 6 AM TO
     10 AM PDT TUESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 7 PM TO
     10 PM PDT TUESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
     10 AM PDT WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 210320 AAA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
820 PM PDT MON APR 20 2015

.SYNOPSIS...INCREASING ONSHORE FLOW WILL RESULT IN COOLER CONDITIONS
TUESDAY AND THEN CONTINUING FOR THE REMAINDER OF THE WEEK. DAYTIME
TEMPERATURES WILL FALL TO NEAR AVERAGE VALUES. A WEAK FRONTAL SYSTEM
WILL MOVE ACROSS THE AREA TUESDAY NIGHT...WHICH WILL REINFORCE THE
MARINE LAYER. A WETTER PATTERN LOOKS TO DEVELOP LATE SATURDAY AND
SUNDAY...WITH PERHAPS ANOTHER ROUND OF WET WEATHER EARLY NEXT WEEK.

&&

.SHORT TERM...00Z LOCAL SURFACE ANALYSIS SHOWED THE THERMALLY-INDUCED
SURFACE TROUGH ALONG THE EAST SLOPES OF THE WASHINGTON CASCADES...
THROUGH THE CENTRAL COLUMBIA GORGE AND EXTENDING ALONG THE OREGON
CASCADE FOOTHILLS. AS EXPECTED...THE 00Z MON NAM WAS TOO FAST MOVING
THE THERMAL TROUGH EAST. LAST AVAILABLE VISIBLE SATELLITE IMAGES
SHOWED A FAIRLY SHALLOW MARINE LAYER ALONG THE OREGON COASTAL
STRIP...BUT STARTING TO PUSH INTO THE DOUGLAS COUNTY COASTAL VALLEYS.
THE 12Z HI RES ARW MODEL LOOKS TO DEPICT THE MARINE LAYER RATHER
WELL. AT 03Z THE MODEL SHOWS 90 PCT OR GREATER BOUNDARY LAYER
MOISTURE STARTING TO PUSH INTO THE CENTRAL COASTAL VALLEYS. ANOTHER
SIGN OF INCREASING ONSHORE FLOW IS THE S-SW WIND AT KMMV. AT 02Z THE
TEMP HAD DROPPED TO 69...WHILE THE KPDX METRO AREA WAS STILL IN THE
MID TO UPPER 70S. TYPICALLY...WITH A SW MARINE SURGE...THE SRN
WILLAMETTE VALLEY PICKS UP A SW BREEZE DURING THE EVENING. AS OF 02Z
KEUG WAS SHOWING CALM CONDITIONS. HOWEVER...AT 03Z KSLE AND KUAO
OBSERVED SW-W WIND UP TO 11 KT. THE HI RES ARW STILL HINTS AT A SW
MARINE SURGE THROUGH THE LANE COUNTY COASTAL GAPS OVERNIGHT. IT ALSO
DEPICTS ANOTHER INTRUSION DOWN THE COLUMBIA RIVER. EXPECT KKLS TO
BECOME OVERCAST LATE TONIGHT OR AROUND SUNRISE TUE.

850 MB TEMPS FALL FROM 12.2C TODAY (00Z KSLE SOUNDING) TO 3-4C BY 00Z
WED. MODELS SHOWING A TIGHT 850 MB TEMP GRADIENT FROM THE CASCADE
CREST TO THE WILLAMETTE VALLEY AND CLARK COUNTY IN SW WA 18Z TUE. THE
MAIN RESULT...OTHER THAN SIGNIFICANT COOLING...WILL BE INCREASED
WIND...ESPECIALLY EAST OF KCZK AND THROUGH COAST RANGE GAPS. SHALLOW
INSTABILITY AND MOISTURE MAY PRODUCE A FEW VERY LIGHT SHOWERS TUESDAY
NIGHT INTO EARLY WEDNESDAY...PARTICULARLY ACROSS THE NORTH AND IN THE
UPSLOPE AREAS...BUT CONFIDENCE IS LOW. NAM...GFS AND ECMWF SURFACE
PATTERN WED AFTERNOON SUGGEST IT COULD END UP PARTLY CLOUDY ACROSS
THE S HALF AS ALL AFOREMENTIONED MODELS HAVE A N-NE SURFACE ISOBAR
CONFIGURATION. WOULD EXPECT LIMITED CLEARING OVER THE N...ESPECIALLY
THE SW WA ZONES CLOSEST TO THE PASSING UPER TROUGH. ANOTHER WEAKENING
FRONT MAY BRING INCREASING PRECIP CHANCES TO THE FAR NORTHWEST ZONES
ON THURSDAY. ALL IN ALL...MOST LOCATIONS LOOK TO REMAIN GENERALLY DRY
THE NEXT FEW DAYS WITH TEMPERATURES TOPPING OUT NEAR AVERAGE.
WEISHAAR

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO
STRUGGLE ON THE DETAILS...BUT SUGGEST ONSHORE FLOW WILL CONTINUE NEAR
AVERAGE TEMPERATURES WITH A CHANCE FOR SOME LIGHT SHOWERS THURSDAY
NIGHT AND FRIDAY. WHILE MODELS DIFFER ON TIMING...BUT THE GFS AND EC
SUGGEST A WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD
ACROSS THE AREA LATE SATURDAY THROUGH SUNDAY NIGHT. AS A
RESULT...POPS WERE INCREASED IN THE LIKELY TO CATEGORICAL RANGE FOR
THE PRIME WINDOW OF SATURDAY NIGHT AND SUNDAY. BOTH MODELS SUGGEST
ANOTHER STORM SYSTEM IS LIKELY NEXT WEEK...BUT ONCE AGAIN DIFFER ON
TIMING SO POPS WERE TRENDED MORE INTO THE HIGH END CHANCE TO LOW END
LIKELY RANGE. /NEUMAN

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES THROUGH THIS EVENING. THE
FLOW PATTERN WILL CONTINUE TO TURN ONSHORE THIS AFTERNOON AS A
WEAK FRONT APPROACHES THE REGION ALLOWING MARINE STRATUS TO FILL
BACK IN ALONG THE COAST - EXPECT IFR CIGS BETWEEN 500 AND 1000 FT
AND REDUCED VSBY THROUGH LATE TUE MORNING. LOW CLOUDS WILL
CONTINUE TO PUSH INLAND TONIGHT...WITH INTERIOR SITES LIKELY
SEEING MVFR CIGS BETWEEN 1500 AND 2000 FT BY 15Z. CONDITIONS TURN
VFR UNDER MOSTLY CLOUDY SKIES TUE AFTERNOON.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
LOWER CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AROUND 2000 FT
AFFECTING THE TERMINAL BY 14Z. VFR RETURNS BY AROUND 18Z TUESDAY
WITH NW WINDS PICKING UP MID AFTERNOON.

&&

.MARINE...INCREASED FORECAST WINDS SLIGHTLY OVER THE NEXT 24
HOURS TO NUDGE CLOSER TO OBS AS WELL AS RUC. BUOY 29 HAS BEEN
GUSTING TO AROUND 20 KT FOR A FEW HOURS BUT SINCE WINDS ARE
INCREDIBLY MARGINAL AND PROBABLY OVER JUST A SMALL AREA...WILL
NOT MOVE UP THE BEGINNING OF THE SMALL CRAFT ADVISORY FOR WINDS. WILL
HAVE A LAST VERY STRONG EBB ON THE COLUMBIA BAR TUESDAY
MORNING...SO ISSUED A SMALL CRAFT ADVISORY FOR ROUGH BAR DURING
THE MORNING EBB AND THEN AGAIN FOR THE TUESDAY EVENING EBB WITH
INCREASE IN SWELL AND WINDS. BOWEN

PREVIOUS DISCUSSION...A WEAK FRONT WILL MOVE ACROSS THE WATERS
TOMORROW MORNING BRINGING GUSTY NORTHWESTERLY WINDS AND BUILDING
SEAS. EXPECT GUSTS TO 30 KT AND SEAS AROUND 11 FT FROM TUE
MORNING TO WED. HIGH PRES BRIEFLY RETURNS WED AFTERNOON BEFORE
ANOTHER WEAK FRONT MOVES ACROSS THE WATERS ON THU. NOT EXPECTING
MUCH IN THE WAY OF IMPACTS WITH THIS SECOND FRONT. A MUCH STRONGER
FRONT LOOKS TO MOVE ACROSS THE WATERS OVER THE WEEKEND AND WILL
LIKELY BRING GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING
SEAS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM TUESDAY TO NOON PDT
     WEDNESDAY FOR WATERS FROM CAPE SHOALWATER WA TO CASCADE
     HEAD OR FROM 10 TO 60 NM-WATERS FROM CASCADE HEAD TO
     FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM TUESDAY TO 6
     PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM TUESDAY TO NOON PDT
     WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     CASCADE HEAD OR OUT 10 NM-COASTAL WATERS FROM CASCADE HEAD
     TO FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 6 AM TO
     10 AM PDT TUESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 7 PM TO
     10 PM PDT TUESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
     10 AM PDT WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 210309
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
806 PM PDT MON APR 20 2015

.SYNOPSIS...INCREASING ONSHORE FLOW WILL RESULT IN COOLER CONDITIONS
TUESDAY AND THEN CONTINUING FOR THE REMAINDER OF THE WEEK. DAYTIME
TEMPERATURES WILL FALL TO NEAR AVERAGE VALUES. A WEAK FRONTAL SYSTEM
WILL MOVE ACROSS THE AREA TUESDAY NIGHT...WHICH WILL REINFORCE THE
MARINE LAYER. A WETTER PATTERN LOOKS TO DEVELOP LATE SATURDAY AND
SUNDAY...WITH PERHAPS ANOTHER ROUND OF WET WEATHER EARLY NEXT WEEK.

&&

.SHORT TERM...00Z LOCAL SURFACE ANALYSIS SHOWED THE THERMALLY-INDUCED
SURFACE TROUGH ALONG THE EAST SLOPES OF THE WASHINGTON CASCADES...
THROUGH THE CENTRAL COLUMBIA GORGE AND EXTENDING ALONG THE OREGON
CASCADE FOOTHILLS. AS EXPECTED...THE 00Z MON NAM WAS TOO FAST MOVING
THE THERMAL TROUGH EAST. LAST AVAILABLE VISIBLE SATELLITE IMAGES
SHOWED A FAIRLY SHALLOW MARINE LAYER ALONG THE OREGON COASTAL
STRIP...BUT STARTING TO PUSH INTO THE DOUGLAS COUNTY COASTAL VALLEYS.
THE 12Z HI RES ARW MODEL LOOKS TO DEPICT THE MARINE LAYER RATHER
WELL. AT 03Z THE MODEL SHOWS 90 PCT OR GREATER BOUNDARY LAYER
MOISTURE STARTING TO PUSH INTO THE CENTRAL COASTAL VALLEYS. ANOTHER
SIGN OF INCREASING ONSHORE FLOW IS THE S-SW WIND AT KMMV. AT 02Z THE
TEMP HAD DROPPED TO 69...WHILE THE KPDX METRO AREA WAS STILL IN THE
MID TO UPPER 70S. TYPICALLY...WITH A SW MARINE SURGE...THE SRN
WILLAMETTE VALLEY PICKS UP A SW BREEZE DURING THE EVENING. AS OF 02Z
KEUG WAS SHOWING CALM CONDITIONS. HOWEVER...AT 03Z KSLE AND KUAO
OBSERVED SW-W WIND UP TO 11 KT. THE HI RES ARW STILL HINTS AT A SW
MARINE SURGE THROUGH THE LANE COUNTY COASTAL GAPS OVERNIGHT. IT ALSO
DEPICTS ANOTHER INTRUSION DOWN THE COLUMBIA RIVER. EXPECT KKLS TO
BECOME OVERCAST LATE TONIGHT OR AROUND SUNRISE TUE.

850 MB TEMPS FALL FROM 12.2C TODAY (00Z KSLE SOUNDING) TO 3-4C BY 00Z
WED. MODELS SHOWING A TIGHT 850 MB TEMP GRADIENT FROM THE CASCADE
CREST TO THE WILLAMETTE VALLEY AND CLARK COUNTY IN SW WA 18Z TUE. THE
MAIN RESULT...OTHER THAN SIGNIFICANT COOLING...WILL BE INCREASED
WIND...ESPECIALLY EAST OF KCZK AND THROUGH COAST RANGE GAPS. SHALLOW
INSTABILITY AND MOISTURE MAY PRODUCE A FEW VERY LIGHT SHOWERS TUESDAY
NIGHT INTO EARLY WEDNESDAY...PARTICULARLY ACROSS THE NORTH AND IN THE
UPSLOPE AREAS...BUT CONFIDENCE IS LOW. NAM...GFS AND ECMWF SURFACE
PATTERN WED AFTERNOON SUGGEST IT COULD END UP PARTLY CLOUDY ACROSS
THE S HALF AS ALL AFOREMENTIONED MODELS HAVE A N-NE SURFACE ISOBAR
CONFIGURATION. WOULD EXPECT LIMITED CLEARING OVER THE N...ESPECIALLY
THE SW WA ZONES CLOSEST TO THE PASSING UPER TROUGH. ANOTHER WEAKENING
FRONT MAY BRING INCREASING PRECIP CHANCES TO THE FAR NORTHWEST ZONES
ON THURSDAY. ALL IN ALL...MOST LOCATIONS LOOK TO REMAIN GENERALLY DRY
THE NEXT FEW DAYS WITH TEMPERATURES TOPPING OUT NEAR AVERAGE.
WEISHAAR

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO
STRUGGLE ON THE DETAILS...BUT SUGGEST ONSHORE FLOW WILL CONTINUE NEAR
AVERAGE TEMPERATURES WITH A CHANCE FOR SOME LIGHT SHOWERS THURSDAY
NIGHT AND FRIDAY. WHILE MODELS DIFFER ON TIMING...BUT THE GFS AND EC
SUGGEST A WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD
ACROSS THE AREA LATE SATURDAY THROUGH SUNDAY NIGHT. AS A
RESULT...POPS WERE INCREASED IN THE LIKELY TO CATEGORICAL RANGE FOR
THE PRIME WINDOW OF SATURDAY NIGHT AND SUNDAY. BOTH MODELS SUGGEST
ANOTHER STORM SYSTEM IS LIKELY NEXT WEEK...BUT ONCE AGAIN DIFFER ON
TIMING SO POPS WERE TRENDED MORE INTO THE HIGH END CHANCE TO LOW END
LIKELY RANGE. /NEUMAN

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES THROUGH THIS EVENING. THE
FLOW PATTERN WILL CONTINUE TO TURN ONSHORE THIS AFTERNOON AS A
WEAK FRONT APPROACHES THE REGION ALLOWING MARINE STRATUS TO FILL
BACK IN ALONG THE COAST - EXPECT IFR CIGS BETWEEN 500 AND 1000 FT
AND REDUCED VSBY THROUGH LATE TUE MORNING. LOW CLOUDS WILL
CONTINUE TO PUSH INLAND TONIGHT...WITH INTERIOR SITES LIKELY
SEEING MVFR CIGS BETWEEN 1500 AND 2000 FT BY 15Z. CONDITIONS TURN
VFR UNDER MOSTLY CLOUDY SKIES TUE AFTERNOON.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
LOWER CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AROUND 2000 FT
AFFECTING THE TERMINAL BY 14Z. VFR RETURNS BY AROUND 18Z TUESDAY
WITH NW WINDS PICKING UP MID AFTERNOON.

&&

.MARINE...INCREASED FORECAST WINDS SLIGHTLY OVER THE NEXT 24
HOURS TO NUDGE CLOSER TO OBS AS WELL AS RUC. BUOY 29 HAS BEEN
GUSTING TO AROUND 20 KT FOR A FEW HOURS BUT SINCE WINDS ARE
INCREDIBLY MARGINAL AND PROBABLY OVER JUST A SMALL AREA...WILL
NOT MOVE UP THE BEGINNING OF THE SMALL CRAFT ADVISORY FOR WINDS. WILL
HAVE A LAST VERY STRONG EBB ON THE COLUMBIA BAR TUESDAY
MORNING...SO ISSUED A SMALL CRAFT ADVISORY FOR ROUGH BAR DURING
THE MORNING EBB AND THEN AGAIN FOR THE TUESDAY EVENING EBB WITH
INCREASE IN SWELL AND WINDS. BOWEN

PREVIOUS DISCUSSION...A WEAK FRONT WILL MOVE ACROSS THE WATERS
TOMORROW MORNING BRINGING GUSTY NORTHWESTERLY WINDS AND BUILDING
SEAS. EXPECT GUSTS TO 30 KT AND SEAS AROUND 11 FT FROM TUE
MORNING TO WED. HIGH PRES BRIEFLY RETURNS WED AFTERNOON BEFORE
ANOTHER WEAK FRONT MOVES ACROSS THE WATERS ON THU. NOT EXPECTING
MUCH IN THE WAY OF IMPACTS WITH THIS SECOND FRONT. A MUCH STRONGER
FRONT LOOKS TO MOVE ACROSS THE WATERS OVER THE WEEKEND AND WILL
LIKELY BRING GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING
SEAS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM TUESDAY TO NOON PDT
     WEDNESDAY FOR WATERS FROM CAPE SHOALWATER WA TO CASCADE
     HEAD OR FROM 10 TO 60 NM-WATERS FROM CASCADE HEAD TO
     FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM TUESDAY TO 6
     PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM TUESDAY TO NOON PDT
     WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     CASCADE HEAD OR OUT 10 NM-COASTAL WATERS FROM CASCADE HEAD
     TO FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 7 AM TO
     10 AM PDT TUESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 7 PM TO
     10 PM PDT TUESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
     10 AM PDT WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 210309
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
806 PM PDT MON APR 20 2015

.SYNOPSIS...INCREASING ONSHORE FLOW WILL RESULT IN COOLER CONDITIONS
TUESDAY AND THEN CONTINUING FOR THE REMAINDER OF THE WEEK. DAYTIME
TEMPERATURES WILL FALL TO NEAR AVERAGE VALUES. A WEAK FRONTAL SYSTEM
WILL MOVE ACROSS THE AREA TUESDAY NIGHT...WHICH WILL REINFORCE THE
MARINE LAYER. A WETTER PATTERN LOOKS TO DEVELOP LATE SATURDAY AND
SUNDAY...WITH PERHAPS ANOTHER ROUND OF WET WEATHER EARLY NEXT WEEK.

&&

.SHORT TERM...00Z LOCAL SURFACE ANALYSIS SHOWED THE THERMALLY-INDUCED
SURFACE TROUGH ALONG THE EAST SLOPES OF THE WASHINGTON CASCADES...
THROUGH THE CENTRAL COLUMBIA GORGE AND EXTENDING ALONG THE OREGON
CASCADE FOOTHILLS. AS EXPECTED...THE 00Z MON NAM WAS TOO FAST MOVING
THE THERMAL TROUGH EAST. LAST AVAILABLE VISIBLE SATELLITE IMAGES
SHOWED A FAIRLY SHALLOW MARINE LAYER ALONG THE OREGON COASTAL
STRIP...BUT STARTING TO PUSH INTO THE DOUGLAS COUNTY COASTAL VALLEYS.
THE 12Z HI RES ARW MODEL LOOKS TO DEPICT THE MARINE LAYER RATHER
WELL. AT 03Z THE MODEL SHOWS 90 PCT OR GREATER BOUNDARY LAYER
MOISTURE STARTING TO PUSH INTO THE CENTRAL COASTAL VALLEYS. ANOTHER
SIGN OF INCREASING ONSHORE FLOW IS THE S-SW WIND AT KMMV. AT 02Z THE
TEMP HAD DROPPED TO 69...WHILE THE KPDX METRO AREA WAS STILL IN THE
MID TO UPPER 70S. TYPICALLY...WITH A SW MARINE SURGE...THE SRN
WILLAMETTE VALLEY PICKS UP A SW BREEZE DURING THE EVENING. AS OF 02Z
KEUG WAS SHOWING CALM CONDITIONS. HOWEVER...AT 03Z KSLE AND KUAO
OBSERVED SW-W WIND UP TO 11 KT. THE HI RES ARW STILL HINTS AT A SW
MARINE SURGE THROUGH THE LANE COUNTY COASTAL GAPS OVERNIGHT. IT ALSO
DEPICTS ANOTHER INTRUSION DOWN THE COLUMBIA RIVER. EXPECT KKLS TO
BECOME OVERCAST LATE TONIGHT OR AROUND SUNRISE TUE.

850 MB TEMPS FALL FROM 12.2C TODAY (00Z KSLE SOUNDING) TO 3-4C BY 00Z
WED. MODELS SHOWING A TIGHT 850 MB TEMP GRADIENT FROM THE CASCADE
CREST TO THE WILLAMETTE VALLEY AND CLARK COUNTY IN SW WA 18Z TUE. THE
MAIN RESULT...OTHER THAN SIGNIFICANT COOLING...WILL BE INCREASED
WIND...ESPECIALLY EAST OF KCZK AND THROUGH COAST RANGE GAPS. SHALLOW
INSTABILITY AND MOISTURE MAY PRODUCE A FEW VERY LIGHT SHOWERS TUESDAY
NIGHT INTO EARLY WEDNESDAY...PARTICULARLY ACROSS THE NORTH AND IN THE
UPSLOPE AREAS...BUT CONFIDENCE IS LOW. NAM...GFS AND ECMWF SURFACE
PATTERN WED AFTERNOON SUGGEST IT COULD END UP PARTLY CLOUDY ACROSS
THE S HALF AS ALL AFOREMENTIONED MODELS HAVE A N-NE SURFACE ISOBAR
CONFIGURATION. WOULD EXPECT LIMITED CLEARING OVER THE N...ESPECIALLY
THE SW WA ZONES CLOSEST TO THE PASSING UPER TROUGH. ANOTHER WEAKENING
FRONT MAY BRING INCREASING PRECIP CHANCES TO THE FAR NORTHWEST ZONES
ON THURSDAY. ALL IN ALL...MOST LOCATIONS LOOK TO REMAIN GENERALLY DRY
THE NEXT FEW DAYS WITH TEMPERATURES TOPPING OUT NEAR AVERAGE.
WEISHAAR

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO
STRUGGLE ON THE DETAILS...BUT SUGGEST ONSHORE FLOW WILL CONTINUE NEAR
AVERAGE TEMPERATURES WITH A CHANCE FOR SOME LIGHT SHOWERS THURSDAY
NIGHT AND FRIDAY. WHILE MODELS DIFFER ON TIMING...BUT THE GFS AND EC
SUGGEST A WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD
ACROSS THE AREA LATE SATURDAY THROUGH SUNDAY NIGHT. AS A
RESULT...POPS WERE INCREASED IN THE LIKELY TO CATEGORICAL RANGE FOR
THE PRIME WINDOW OF SATURDAY NIGHT AND SUNDAY. BOTH MODELS SUGGEST
ANOTHER STORM SYSTEM IS LIKELY NEXT WEEK...BUT ONCE AGAIN DIFFER ON
TIMING SO POPS WERE TRENDED MORE INTO THE HIGH END CHANCE TO LOW END
LIKELY RANGE. /NEUMAN

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES THROUGH THIS EVENING. THE
FLOW PATTERN WILL CONTINUE TO TURN ONSHORE THIS AFTERNOON AS A
WEAK FRONT APPROACHES THE REGION ALLOWING MARINE STRATUS TO FILL
BACK IN ALONG THE COAST - EXPECT IFR CIGS BETWEEN 500 AND 1000 FT
AND REDUCED VSBY THROUGH LATE TUE MORNING. LOW CLOUDS WILL
CONTINUE TO PUSH INLAND TONIGHT...WITH INTERIOR SITES LIKELY
SEEING MVFR CIGS BETWEEN 1500 AND 2000 FT BY 15Z. CONDITIONS TURN
VFR UNDER MOSTLY CLOUDY SKIES TUE AFTERNOON.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
LOWER CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AROUND 2000 FT
AFFECTING THE TERMINAL BY 14Z. VFR RETURNS BY AROUND 18Z TUESDAY
WITH NW WINDS PICKING UP MID AFTERNOON.

&&

.MARINE...INCREASED FORECAST WINDS SLIGHTLY OVER THE NEXT 24
HOURS TO NUDGE CLOSER TO OBS AS WELL AS RUC. BUOY 29 HAS BEEN
GUSTING TO AROUND 20 KT FOR A FEW HOURS BUT SINCE WINDS ARE
INCREDIBLY MARGINAL AND PROBABLY OVER JUST A SMALL AREA...WILL
NOT MOVE UP THE BEGINNING OF THE SMALL CRAFT ADVISORY FOR WINDS. WILL
HAVE A LAST VERY STRONG EBB ON THE COLUMBIA BAR TUESDAY
MORNING...SO ISSUED A SMALL CRAFT ADVISORY FOR ROUGH BAR DURING
THE MORNING EBB AND THEN AGAIN FOR THE TUESDAY EVENING EBB WITH
INCREASE IN SWELL AND WINDS. BOWEN

PREVIOUS DISCUSSION...A WEAK FRONT WILL MOVE ACROSS THE WATERS
TOMORROW MORNING BRINGING GUSTY NORTHWESTERLY WINDS AND BUILDING
SEAS. EXPECT GUSTS TO 30 KT AND SEAS AROUND 11 FT FROM TUE
MORNING TO WED. HIGH PRES BRIEFLY RETURNS WED AFTERNOON BEFORE
ANOTHER WEAK FRONT MOVES ACROSS THE WATERS ON THU. NOT EXPECTING
MUCH IN THE WAY OF IMPACTS WITH THIS SECOND FRONT. A MUCH STRONGER
FRONT LOOKS TO MOVE ACROSS THE WATERS OVER THE WEEKEND AND WILL
LIKELY BRING GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING
SEAS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM TUESDAY TO NOON PDT
     WEDNESDAY FOR WATERS FROM CAPE SHOALWATER WA TO CASCADE
     HEAD OR FROM 10 TO 60 NM-WATERS FROM CASCADE HEAD TO
     FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM TUESDAY TO 6
     PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM TUESDAY TO NOON PDT
     WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     CASCADE HEAD OR OUT 10 NM-COASTAL WATERS FROM CASCADE HEAD
     TO FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 7 AM TO
     10 AM PDT TUESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 7 PM TO
     10 PM PDT TUESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
     10 AM PDT WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KOTX 202334
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
434 PM PDT MON APR 20 2015

.SYNOPSIS...

Tuesday will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday.

&&

.DISCUSSION...

Tonight through Tuesday night...The axis of the ridge of high
pressure influencing the area moves east tomorrow. It does this at
slow enough of a speed to allow for temperatures of the seven day
forecast to peak for most locations tomorrow. Late in the
afternoon and evening with the axis to the east a weak marine push
of sorts allows for winds to increase in the gaps of the cascades
and close proximity to them late Tuesday afternoon and overnight.
The weak push may also fire off a bit of spotty convective showers
and perhaps a thunderstorm or two. Minimum temperatures Tuesday
night should be on the warm side of normal given the mixing
brought about by the wind. /Pelatti

Wednesday: Cooler and breezy weather will arrive Tuesday night
into Wednesday. The high amplitude 500mb ridge responsible for our
recent warm weather will be replaced by a cool polar low
descending out of the Gulf of Alaska. A relatively high spread in
model solutions continues for a day 3 forecast leading to lower
than average confidence for precipitation chances and winds for
Wednesday. The GFS model continues to be an outlier digging an
upper low deeper south into Washington on Wednesday. The ECMWF,
Canadian and NAM models look to have a more reasonable progressive
solution. The deeper/slower low on GFS looks a bit suspect given
the strong upstream kicker in the Gulf of Alaska, so the forecast
for Wednesday and Thursday was largely based on the Canadian
which is a compromise between the ECMWF and NAM.

This Canadian compromise means less chance for thunderstorms since
the heart of the 500mb cold pool will only graze the northern
Washington zones. This solution also entrains a good deal of mid-
level dry air into the region on Wednesday limiting the amount of
deep layer instability. Precipitation chances region-wide don`t
look very impressive. The Canadian and ECMWF solutions are a bit
breezier, so winds have been increased. We will likely see a 10
to 12 degree cool down from Tuesday into Wednesday as chilly
maritime air is squeezed through the gaps in the Cascades. The
change in air mass will likely be accompanied by typical breezy
spring time winds between 15 and 20 mph with some wind prone areas
in the lee of the Cascades gusting in excess of 30 mph on
Wednesday.

Thursday: If we discount the GFS, Thursday has the potential to be
a relatively dry day with fairly light winds. Precipitation
chances have been trimmed, limited to 20 percent or less in the
mountainous. Light winds and a good chance for mainly clear skies
suggest a fairly chilly morning on Thursday. Sheltered areas in
the Idaho Panhandle and northeast Washington will have a good shot
at low to mid 30s...perhaps a frost.

Friday and Saturday: By Friday, the main longwave trough over the
Gulf of Alaska is expected to move into Washington or southern
British Columbia. Seasonably chilly temperatures and showers will
likely accompany the arrival of this broad polar trough. Our
temperature forecast for Friday into Saturday has been cooled in
line with MOS guidance.

Sunday and Monday: Given the model uncertainty in the Wednesday
through Saturday time frame, it is a bit unusual to see the GFS,
ECMWF, and Canadian come into better agreement early next week.
The model consensus is for a mild and wet pattern Sunday and
Monday as a subtropical moisture plume becomes planted over the
Pacific Northwest. Early next week looks like our best shot of
widespread precipitation during the next 7 to 10 day period.
/GKoch

&&

.AVIATION...
00Z TAFS: High pressure will result in VFR conditions and weak
winds at all TAF sites through Tuesday afternoon. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        46  74  50  61  36  62 /   0  10  10  20  10  10
Coeur d`Alene  41  73  44  62  34  62 /   0  10  10  20  20  10
Pullman        42  72  46  58  34  61 /   0  10  10  30  10  10
Lewiston       46  78  49  65  38  66 /   0   0  10  30  10  10
Colville       42  77  46  65  37  65 /   0  10  10  40  40  20
Sandpoint      38  72  40  61  33  60 /   0  10  10  30  30  20
Kellogg        40  71  43  59  34  62 /   0  10  10  30  20  20
Moses Lake     44  78  50  67  37  66 /   0  10  10  10   0  10
Wenatchee      51  77  53  65  41  65 /   0  10  10  10   0  10
Omak           44  77  47  65  35  64 /   0  10  10  30  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 202334
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
434 PM PDT MON APR 20 2015

.SYNOPSIS...

Tuesday will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday.

&&

.DISCUSSION...

Tonight through Tuesday night...The axis of the ridge of high
pressure influencing the area moves east tomorrow. It does this at
slow enough of a speed to allow for temperatures of the seven day
forecast to peak for most locations tomorrow. Late in the
afternoon and evening with the axis to the east a weak marine push
of sorts allows for winds to increase in the gaps of the cascades
and close proximity to them late Tuesday afternoon and overnight.
The weak push may also fire off a bit of spotty convective showers
and perhaps a thunderstorm or two. Minimum temperatures Tuesday
night should be on the warm side of normal given the mixing
brought about by the wind. /Pelatti

Wednesday: Cooler and breezy weather will arrive Tuesday night
into Wednesday. The high amplitude 500mb ridge responsible for our
recent warm weather will be replaced by a cool polar low
descending out of the Gulf of Alaska. A relatively high spread in
model solutions continues for a day 3 forecast leading to lower
than average confidence for precipitation chances and winds for
Wednesday. The GFS model continues to be an outlier digging an
upper low deeper south into Washington on Wednesday. The ECMWF,
Canadian and NAM models look to have a more reasonable progressive
solution. The deeper/slower low on GFS looks a bit suspect given
the strong upstream kicker in the Gulf of Alaska, so the forecast
for Wednesday and Thursday was largely based on the Canadian
which is a compromise between the ECMWF and NAM.

This Canadian compromise means less chance for thunderstorms since
the heart of the 500mb cold pool will only graze the northern
Washington zones. This solution also entrains a good deal of mid-
level dry air into the region on Wednesday limiting the amount of
deep layer instability. Precipitation chances region-wide don`t
look very impressive. The Canadian and ECMWF solutions are a bit
breezier, so winds have been increased. We will likely see a 10
to 12 degree cool down from Tuesday into Wednesday as chilly
maritime air is squeezed through the gaps in the Cascades. The
change in air mass will likely be accompanied by typical breezy
spring time winds between 15 and 20 mph with some wind prone areas
in the lee of the Cascades gusting in excess of 30 mph on
Wednesday.

Thursday: If we discount the GFS, Thursday has the potential to be
a relatively dry day with fairly light winds. Precipitation
chances have been trimmed, limited to 20 percent or less in the
mountainous. Light winds and a good chance for mainly clear skies
suggest a fairly chilly morning on Thursday. Sheltered areas in
the Idaho Panhandle and northeast Washington will have a good shot
at low to mid 30s...perhaps a frost.

Friday and Saturday: By Friday, the main longwave trough over the
Gulf of Alaska is expected to move into Washington or southern
British Columbia. Seasonably chilly temperatures and showers will
likely accompany the arrival of this broad polar trough. Our
temperature forecast for Friday into Saturday has been cooled in
line with MOS guidance.

Sunday and Monday: Given the model uncertainty in the Wednesday
through Saturday time frame, it is a bit unusual to see the GFS,
ECMWF, and Canadian come into better agreement early next week.
The model consensus is for a mild and wet pattern Sunday and
Monday as a subtropical moisture plume becomes planted over the
Pacific Northwest. Early next week looks like our best shot of
widespread precipitation during the next 7 to 10 day period.
/GKoch

&&

.AVIATION...
00Z TAFS: High pressure will result in VFR conditions and weak
winds at all TAF sites through Tuesday afternoon. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        46  74  50  61  36  62 /   0  10  10  20  10  10
Coeur d`Alene  41  73  44  62  34  62 /   0  10  10  20  20  10
Pullman        42  72  46  58  34  61 /   0  10  10  30  10  10
Lewiston       46  78  49  65  38  66 /   0   0  10  30  10  10
Colville       42  77  46  65  37  65 /   0  10  10  40  40  20
Sandpoint      38  72  40  61  33  60 /   0  10  10  30  30  20
Kellogg        40  71  43  59  34  62 /   0  10  10  30  20  20
Moses Lake     44  78  50  67  37  66 /   0  10  10  10   0  10
Wenatchee      51  77  53  65  41  65 /   0  10  10  10   0  10
Omak           44  77  47  65  35  64 /   0  10  10  30  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 202334
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
434 PM PDT MON APR 20 2015

.SYNOPSIS...

Tuesday will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday.

&&

.DISCUSSION...

Tonight through Tuesday night...The axis of the ridge of high
pressure influencing the area moves east tomorrow. It does this at
slow enough of a speed to allow for temperatures of the seven day
forecast to peak for most locations tomorrow. Late in the
afternoon and evening with the axis to the east a weak marine push
of sorts allows for winds to increase in the gaps of the cascades
and close proximity to them late Tuesday afternoon and overnight.
The weak push may also fire off a bit of spotty convective showers
and perhaps a thunderstorm or two. Minimum temperatures Tuesday
night should be on the warm side of normal given the mixing
brought about by the wind. /Pelatti

Wednesday: Cooler and breezy weather will arrive Tuesday night
into Wednesday. The high amplitude 500mb ridge responsible for our
recent warm weather will be replaced by a cool polar low
descending out of the Gulf of Alaska. A relatively high spread in
model solutions continues for a day 3 forecast leading to lower
than average confidence for precipitation chances and winds for
Wednesday. The GFS model continues to be an outlier digging an
upper low deeper south into Washington on Wednesday. The ECMWF,
Canadian and NAM models look to have a more reasonable progressive
solution. The deeper/slower low on GFS looks a bit suspect given
the strong upstream kicker in the Gulf of Alaska, so the forecast
for Wednesday and Thursday was largely based on the Canadian
which is a compromise between the ECMWF and NAM.

This Canadian compromise means less chance for thunderstorms since
the heart of the 500mb cold pool will only graze the northern
Washington zones. This solution also entrains a good deal of mid-
level dry air into the region on Wednesday limiting the amount of
deep layer instability. Precipitation chances region-wide don`t
look very impressive. The Canadian and ECMWF solutions are a bit
breezier, so winds have been increased. We will likely see a 10
to 12 degree cool down from Tuesday into Wednesday as chilly
maritime air is squeezed through the gaps in the Cascades. The
change in air mass will likely be accompanied by typical breezy
spring time winds between 15 and 20 mph with some wind prone areas
in the lee of the Cascades gusting in excess of 30 mph on
Wednesday.

Thursday: If we discount the GFS, Thursday has the potential to be
a relatively dry day with fairly light winds. Precipitation
chances have been trimmed, limited to 20 percent or less in the
mountainous. Light winds and a good chance for mainly clear skies
suggest a fairly chilly morning on Thursday. Sheltered areas in
the Idaho Panhandle and northeast Washington will have a good shot
at low to mid 30s...perhaps a frost.

Friday and Saturday: By Friday, the main longwave trough over the
Gulf of Alaska is expected to move into Washington or southern
British Columbia. Seasonably chilly temperatures and showers will
likely accompany the arrival of this broad polar trough. Our
temperature forecast for Friday into Saturday has been cooled in
line with MOS guidance.

Sunday and Monday: Given the model uncertainty in the Wednesday
through Saturday time frame, it is a bit unusual to see the GFS,
ECMWF, and Canadian come into better agreement early next week.
The model consensus is for a mild and wet pattern Sunday and
Monday as a subtropical moisture plume becomes planted over the
Pacific Northwest. Early next week looks like our best shot of
widespread precipitation during the next 7 to 10 day period.
/GKoch

&&

.AVIATION...
00Z TAFS: High pressure will result in VFR conditions and weak
winds at all TAF sites through Tuesday afternoon. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        46  74  50  61  36  62 /   0  10  10  20  10  10
Coeur d`Alene  41  73  44  62  34  62 /   0  10  10  20  20  10
Pullman        42  72  46  58  34  61 /   0  10  10  30  10  10
Lewiston       46  78  49  65  38  66 /   0   0  10  30  10  10
Colville       42  77  46  65  37  65 /   0  10  10  40  40  20
Sandpoint      38  72  40  61  33  60 /   0  10  10  30  30  20
Kellogg        40  71  43  59  34  62 /   0  10  10  30  20  20
Moses Lake     44  78  50  67  37  66 /   0  10  10  10   0  10
Wenatchee      51  77  53  65  41  65 /   0  10  10  10   0  10
Omak           44  77  47  65  35  64 /   0  10  10  30  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 202334
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
434 PM PDT MON APR 20 2015

.SYNOPSIS...

Tuesday will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday.

&&

.DISCUSSION...

Tonight through Tuesday night...The axis of the ridge of high
pressure influencing the area moves east tomorrow. It does this at
slow enough of a speed to allow for temperatures of the seven day
forecast to peak for most locations tomorrow. Late in the
afternoon and evening with the axis to the east a weak marine push
of sorts allows for winds to increase in the gaps of the cascades
and close proximity to them late Tuesday afternoon and overnight.
The weak push may also fire off a bit of spotty convective showers
and perhaps a thunderstorm or two. Minimum temperatures Tuesday
night should be on the warm side of normal given the mixing
brought about by the wind. /Pelatti

Wednesday: Cooler and breezy weather will arrive Tuesday night
into Wednesday. The high amplitude 500mb ridge responsible for our
recent warm weather will be replaced by a cool polar low
descending out of the Gulf of Alaska. A relatively high spread in
model solutions continues for a day 3 forecast leading to lower
than average confidence for precipitation chances and winds for
Wednesday. The GFS model continues to be an outlier digging an
upper low deeper south into Washington on Wednesday. The ECMWF,
Canadian and NAM models look to have a more reasonable progressive
solution. The deeper/slower low on GFS looks a bit suspect given
the strong upstream kicker in the Gulf of Alaska, so the forecast
for Wednesday and Thursday was largely based on the Canadian
which is a compromise between the ECMWF and NAM.

This Canadian compromise means less chance for thunderstorms since
the heart of the 500mb cold pool will only graze the northern
Washington zones. This solution also entrains a good deal of mid-
level dry air into the region on Wednesday limiting the amount of
deep layer instability. Precipitation chances region-wide don`t
look very impressive. The Canadian and ECMWF solutions are a bit
breezier, so winds have been increased. We will likely see a 10
to 12 degree cool down from Tuesday into Wednesday as chilly
maritime air is squeezed through the gaps in the Cascades. The
change in air mass will likely be accompanied by typical breezy
spring time winds between 15 and 20 mph with some wind prone areas
in the lee of the Cascades gusting in excess of 30 mph on
Wednesday.

Thursday: If we discount the GFS, Thursday has the potential to be
a relatively dry day with fairly light winds. Precipitation
chances have been trimmed, limited to 20 percent or less in the
mountainous. Light winds and a good chance for mainly clear skies
suggest a fairly chilly morning on Thursday. Sheltered areas in
the Idaho Panhandle and northeast Washington will have a good shot
at low to mid 30s...perhaps a frost.

Friday and Saturday: By Friday, the main longwave trough over the
Gulf of Alaska is expected to move into Washington or southern
British Columbia. Seasonably chilly temperatures and showers will
likely accompany the arrival of this broad polar trough. Our
temperature forecast for Friday into Saturday has been cooled in
line with MOS guidance.

Sunday and Monday: Given the model uncertainty in the Wednesday
through Saturday time frame, it is a bit unusual to see the GFS,
ECMWF, and Canadian come into better agreement early next week.
The model consensus is for a mild and wet pattern Sunday and
Monday as a subtropical moisture plume becomes planted over the
Pacific Northwest. Early next week looks like our best shot of
widespread precipitation during the next 7 to 10 day period.
/GKoch

&&

.AVIATION...
00Z TAFS: High pressure will result in VFR conditions and weak
winds at all TAF sites through Tuesday afternoon. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        46  74  50  61  36  62 /   0  10  10  20  10  10
Coeur d`Alene  41  73  44  62  34  62 /   0  10  10  20  20  10
Pullman        42  72  46  58  34  61 /   0  10  10  30  10  10
Lewiston       46  78  49  65  38  66 /   0   0  10  30  10  10
Colville       42  77  46  65  37  65 /   0  10  10  40  40  20
Sandpoint      38  72  40  61  33  60 /   0  10  10  30  30  20
Kellogg        40  71  43  59  34  62 /   0  10  10  30  20  20
Moses Lake     44  78  50  67  37  66 /   0  10  10  10   0  10
Wenatchee      51  77  53  65  41  65 /   0  10  10  10   0  10
Omak           44  77  47  65  35  64 /   0  10  10  30  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KSEW 202208
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
300 PM PDT MON APR 20 2015

.SYNOPSIS...THE WARM SUNNY WEATHER TODAY WILL BE FOLLOWED BY COOL
MARINE AIR PUSHING INTO WESTERN WASHINGTON TUESDAY. AN UPPER TROUGH
AND COLD FRONT WILL REACH WESTERN WASHINGTON BY TUESDAY NIGHT.
ANOTHER FRONT FRONT WILL ARRIVE LATER THURSDAY. A STRONGER WEATHER
SYSTEM IS LIKELY TO REACH THE AREA OVER THE WEEKEND.

&&

.SHORT TERM...THE RIDGE IS WEAKENING AND WILL MOVE SLOWLY INLAND
THROUGH TUESDAY. AN UPPER TROUGH AND COLD FRONT ARE CROSSING 130W
THIS AFTERNOON. ONSHORE FLOW WILL INCREASE TONIGHT AND TUESDAY AND
AS THE TROUGH AND REMNANTS OF THE COLD FRONT ARRIVE THE CHANCE OF
SHOWERS WILL INCREASE TUESDAY AFTERNOON AND NIGHT. THERE IS A GOOD
CHANCE OF A PUGET SOUND CONVERGENCE ZONE TUESDAY NIGHT INTO
WEDNESDAY MORNING. ANOTHER FRONT SHOULD REACH WRN WA THU AFTERNOON.

.LONG TERM...THERE MAY BE A BRIEF PERIOD OF WEAK RIDGING TOWARD THE
END OF THE WORK WEEK BEFORE A COUPLE OF STRONGER FRONTAL WAVES REACH
THE AREA. A LARGE UPPER TROUGH WILL TAKE UP RESIDENCE IN THE NE
PACIFIC AND SPIN OUT SEVERAL SYSTEMS BETWEEN SATURDAY AND THE MIDDLE
OF NEXT WEEK. THE EXTENDED FORECAST IS JUST A BROADBRUSH FORECAST
FOR RAIN LIKELY AS IT IS TOO EARLY TO TIME THE BREAKS BETWEEN
FRONTS...FOR THE MOMENT SATURDAY NIGHT AND SUNDAY MORNING LOOK THE
WETTEST.

&&

.AVIATION...THE UPPER LEVEL RIDGE OVER WESTERN WASHINGTON THIS
AFTERNOON WILL WEAKEN AS IT MOVES EAST OF THE CASCADES TONIGHT. A
WEAK COLD FRONT WILL MOVE THROUGH THE FORECAST AREA TUESDAY...
FOLLOWED BY ITS UPPER TROUGH TUESDAY NIGHT. SOUTHWEST FLOW ALOFT
WILL DEVELOP TONIGHT AND CONTINUE TUESDAY. THE AIR MASS WILL BECOME
MOIST LATE TONIGHT AND TUESDAY AS LOW LEVEL ONSHORE FLOW INCREASES.

MARINE STRATUS ALONG THE COAST THIS AFTERNOON WILL DEEPEN AND PUSH
INLAND AT LEAST WEAKLY TONIGHT. THE MAIN FORECAST PROBLEM IS HOW
STRONG THE MARINE PUSH WILL BE...AND WHETHER THERE WILL BE MUCH
MORNING STRATUS OVER THE WESTERN WASHINGTON INTERIOR LOWLANDS
TUESDAY MORNING. AT THIS TIME THE PUSH LOOKS RATHER WEAK. STRATUS IS
LIKELY TO REACH OLYMPIA LATE TONIGHT...BUT IT WILL PROBABLY RATHER
THIN AND SHORT LIVED IN THE CENTRAL PUGET SOUND REGION TUESDAY
MORNING.

KSEA...NORTH WIND TO 10 KT...BECOMING SOUTHERLY TO 8 KT LATE
TONIGHT...AND SOUTHWEST 6-12 KT TUESDAY AFTERNOON. MARINE STRATUS
WILL PROBABLY REACH KSEA AROUND 13Z WITH SEVERAL HOURS OF SCT-BKN005
TUESDAY MORNING.   MCDONNAL

&&

.MARINE...ONSHORE FLOW WILL STRENGTHEN TONIGHT AS LOW PRESSURE OVER
WESTERN WASHINGTON MOVES EAST OF THE CASCADES. SMALL CRAFT ADVISORY
WINDS ARE LIKELY OVER THE COASTAL WATERS...WESTERN AND CENTRAL
STRAIT OF JUAN DE FUCA...ADMIRALTY INLET...AND NORTHERN INLAND
WATERS. THE STRONGEST WINDS SHOULD OCCUR IN THE CENTRAL AND EASTERN
STRAIT.

ONSHORE FLOW WILL INCREASE FURTHER TUESDAY AND TUESDAY NIGHT AS A
WEAK COLD FRONT MOVES INLAND. GALE WESTERLIES ARE A VERY GOOD BET
FOR THE CENTRAL AND EASTERN STRAIT...AND I HAVE UPGRADED THE GALE
WATCH TO A WARNING WITH THE AFTERNOON FORECAST PACKAGE. MARGINAL
GALES ARE POSSIBLE OVER THE NORTHWEST COASTAL WATERS TOO...BUT I
WILL LEAVE THAT AS A GALE WATCH FOR NOW. SMALL CRAFT ADVISORY WINDS
SHOULD OCCUR...OR CONTINUE...FOR ALL OTHER MARINE ZONES EXCEPT MAYBE
PUGET SOUND AND HOOD CANAL.

ANOTHER WEAK COLD FRONT WILL CROSS THE FORECAST AREA THURSDAY AND
THURSDAY NIGHT...WITH A STRONGER FRONTAL SYSTEM REACHING THE AREA
SATURDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY COASTAL WATERS...CENTRAL AND EASTERN
       STRAIT OF JUAN DE FUCA...ADMIRALTY INLET...NORTHERN INLAND
       WATERS.
    .GALE WARNING FOR TUESDAY NIGHT CENTRAL AND EASTERN STRAIT.
    .GALE WATCH FOR TUESDAY NIGHT COASTAL WATERS ZONES 150 170 173.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML







000
FXUS66 KPQR 202156
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
236 PM PDT MON APR 20 2015

.SYNOPSIS...INCREASING ONSHORE FLOW WILL LEAD TO NEAR AVERAGE
TEMPERATURES AND AN INCREASE IN MARINE CLOUDS TUESDAY THROUGH FRIDAY.
THERE WILL BE A SMALL CHANCE OF A SHOWER EACH DAY DURING THIS
PERIOD...PARTICULARLY ALONG THE COAST AND CASCADES...BUT MOST
LOCATIONS WILL GENERALLY REMAIN DRY. A WETTER PATTERN LOOKS TO
DEVELOP LATE SATURDAY AND SUNDAY...WITH PERHAPS ANOTHER ROUND OF WET
WEATHER EARLY NEXT WEEK.

&&

.SHORT TERM...VISIBLE SATELLITE IMAGERY REVEALS MAINLY CLEAR SKIES
ACROSS THE AREA EXCEPT FOR SOME LOW CLOUDS SKIRTING THE COASTLINE
UNDER LOW LEVEL NORTHERLY FLOW. SURFACE LOW PRESSURE IS SHIFTING
INLAND THIS AFTERNOON...WHICH WILL RESULT IN LOW CLOUDS PUSHING INTO
THE COAST RANGE GAPS THIS EVENING...AND PERHAPS A BRIEF SURGE OF
WESTERLY WINDS. LOW CLOUDS SHOULD SPREAD INTO THE WILLAMETTE VALLEY
OVERNIGHT AND TUESDAY MORNING...BUT DUE TO THE SHALLOW NATURE OF THE
THIS MARINE PUSH...THE CURRENT CLOUD COVER FORECAST IN THE WILLAMETTE
VALLEY MAY BE A BIT TOO PESSIMISTIC...ESPECIALLY ACROSS THE SOUTHERN
AND WESTERN PORTIONS OF THE VALLEY.

TEMPERATURES ON TUESDAY SHOULD TOP OUT APPROXIMATELY 10F COOLER THAN
TODAY DUE TO THE MUCH STRONGER MARINE INFLUENCE EXPECTED IN THE
WILLAMETTE VALLEY. ONSHORE PRESSURE GRADIENTS LOOK TO INCREASE
FURTHER TUESDAY AFTERNOON AND EVENING SO EXPECT BREEZY CONDITIONS TO
DEVELOP...ESPECIALLY NEAR THE COAST RANGE GAPS AND CENTRAL COLUMBIA
RIVER GORGE IN THE LATE AFTERNOON AND EVENING HOURS.

SHALLOW INSTABILITY AND MOISTURE MAY PRODUCE A FEW VERY LIGHT SHOWERS
TUESDAY NIGHT INTO EARLY WEDNESDAY...PARTICULARLY ACROSS THE NORTH
AND IN THE UPSLOPE AREAS...BUT CONFIDENCE IS LOW. A WEAKENING FRONT
MAY BRING INCREASING LIGHT RAIN CHANCES TO OUR FAR NORTHWEST ZONES
ON THURSDAY. ALL IN ALL...MOST LOCATIONS LOOK TO REMAIN GENERALLY
DRY THE NEXT FEW DAYS WITH TEMPERATURES TOPPING OUT NEAR AVERAGE.
/NEUMAN

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO
STRUGGLE ON THE DETAILS...BUT SUGGEST ONSHORE FLOW WILL CONTINUE NEAR
AVERAGE TEMPERATURES WITH A CHANCE FOR SOME LIGHT SHOWERS THURSDAY
NIGHT AND FRIDAY. WHILE MODELS DIFFER ON TIMING...BUT THE GFS AND EC
SUGGEST A WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD
ACROSS THE AREA LATE SATURDAY THROUGH SUNDAY NIGHT. AS A
RESULT...POPS WERE INCREASED IN THE LIKELY TO CATEGORICAL RANGE FOR
THE PRIME WINDOW OF SATURDAY NIGHT AND SUNDAY. BOTH MODELS SUGGEST
ANOTHER STORM SYSTEM IS LIKELY NEXT WEEK...BUT ONCE AGAIN DIFFER ON
TIMING SO POPS WERE TRENDED MORE INTO THE HIGH END CHANCE TO LOW END
LIKELY RANGE. /NEUMAN

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES THROUGH THIS EVENING. THE
FLOW PATTERN WILL CONTINUE TO TURN ONSHORE THIS AFTERNOON AS A
WEAK FRONT APPROACHES THE REGION ALLOWING MARINE STRATUS TO FILL
BACK IN ALONG THE COAST BETWEEN 00Z AND 03Z. EXPECT IFR CIGS
BETWEEN 500 AND 1000 FT AND REDUCED VSBY ALONG THE COAST THROUGH
LATE TUE MORNING. CLOUDS CONTINUE TO PUSH INLAND TONIGHT...WITH
INTERIOR SITE LIKELY SEEING MVFR CIGS BETWEEN 1500 AND 2000 FT BY
15Z. CONDITIONS TURN VFR UNDER MOSTLY CLOUDY SKIES TUE AFTERNOON.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
LOWER CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AFFECTING THE
TERMINAL BY 14Z.

&&

.MARINE...A WEAK FRONT WILL MOVE ACROSS THE WATERS TOMORROW
MORNING BRINGING GUSTY NORTHWESTERLY WINDS AND BUILDING SEAS.
EXPECT GUSTS TO 35 KT AND SEAS AROUND 11 FT FROM TUE MORNING TO
WED. HIGH PRES BRIEFLY RETURNS WED AFTERNOON BEFORE ANOTHER WEAK
FRONT MOVES ACROSS THE WATERS ON THU. NOT EXPECTING MUCH IN THE
WAY OF IMPACTS WITH THIS SECOND FRONT. A MUCH STRONGER FRONT LOOKS
TO MOVE ACROSS THE WATERS OVER THE WEEKEND AND WILL LIKELY BRING
GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING SEAS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM TUESDAY TO NOON PDT
     WEDNESDAY FOR WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR
     FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM TUESDAY TO 6
     PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM TUESDAY TO NOON PDT
     WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM
     TO 10 AM PDT WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 202156
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
236 PM PDT MON APR 20 2015

.SYNOPSIS...INCREASING ONSHORE FLOW WILL LEAD TO NEAR AVERAGE
TEMPERATURES AND AN INCREASE IN MARINE CLOUDS TUESDAY THROUGH FRIDAY.
THERE WILL BE A SMALL CHANCE OF A SHOWER EACH DAY DURING THIS
PERIOD...PARTICULARLY ALONG THE COAST AND CASCADES...BUT MOST
LOCATIONS WILL GENERALLY REMAIN DRY. A WETTER PATTERN LOOKS TO
DEVELOP LATE SATURDAY AND SUNDAY...WITH PERHAPS ANOTHER ROUND OF WET
WEATHER EARLY NEXT WEEK.

&&

.SHORT TERM...VISIBLE SATELLITE IMAGERY REVEALS MAINLY CLEAR SKIES
ACROSS THE AREA EXCEPT FOR SOME LOW CLOUDS SKIRTING THE COASTLINE
UNDER LOW LEVEL NORTHERLY FLOW. SURFACE LOW PRESSURE IS SHIFTING
INLAND THIS AFTERNOON...WHICH WILL RESULT IN LOW CLOUDS PUSHING INTO
THE COAST RANGE GAPS THIS EVENING...AND PERHAPS A BRIEF SURGE OF
WESTERLY WINDS. LOW CLOUDS SHOULD SPREAD INTO THE WILLAMETTE VALLEY
OVERNIGHT AND TUESDAY MORNING...BUT DUE TO THE SHALLOW NATURE OF THE
THIS MARINE PUSH...THE CURRENT CLOUD COVER FORECAST IN THE WILLAMETTE
VALLEY MAY BE A BIT TOO PESSIMISTIC...ESPECIALLY ACROSS THE SOUTHERN
AND WESTERN PORTIONS OF THE VALLEY.

TEMPERATURES ON TUESDAY SHOULD TOP OUT APPROXIMATELY 10F COOLER THAN
TODAY DUE TO THE MUCH STRONGER MARINE INFLUENCE EXPECTED IN THE
WILLAMETTE VALLEY. ONSHORE PRESSURE GRADIENTS LOOK TO INCREASE
FURTHER TUESDAY AFTERNOON AND EVENING SO EXPECT BREEZY CONDITIONS TO
DEVELOP...ESPECIALLY NEAR THE COAST RANGE GAPS AND CENTRAL COLUMBIA
RIVER GORGE IN THE LATE AFTERNOON AND EVENING HOURS.

SHALLOW INSTABILITY AND MOISTURE MAY PRODUCE A FEW VERY LIGHT SHOWERS
TUESDAY NIGHT INTO EARLY WEDNESDAY...PARTICULARLY ACROSS THE NORTH
AND IN THE UPSLOPE AREAS...BUT CONFIDENCE IS LOW. A WEAKENING FRONT
MAY BRING INCREASING LIGHT RAIN CHANCES TO OUR FAR NORTHWEST ZONES
ON THURSDAY. ALL IN ALL...MOST LOCATIONS LOOK TO REMAIN GENERALLY
DRY THE NEXT FEW DAYS WITH TEMPERATURES TOPPING OUT NEAR AVERAGE.
/NEUMAN

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO
STRUGGLE ON THE DETAILS...BUT SUGGEST ONSHORE FLOW WILL CONTINUE NEAR
AVERAGE TEMPERATURES WITH A CHANCE FOR SOME LIGHT SHOWERS THURSDAY
NIGHT AND FRIDAY. WHILE MODELS DIFFER ON TIMING...BUT THE GFS AND EC
SUGGEST A WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD
ACROSS THE AREA LATE SATURDAY THROUGH SUNDAY NIGHT. AS A
RESULT...POPS WERE INCREASED IN THE LIKELY TO CATEGORICAL RANGE FOR
THE PRIME WINDOW OF SATURDAY NIGHT AND SUNDAY. BOTH MODELS SUGGEST
ANOTHER STORM SYSTEM IS LIKELY NEXT WEEK...BUT ONCE AGAIN DIFFER ON
TIMING SO POPS WERE TRENDED MORE INTO THE HIGH END CHANCE TO LOW END
LIKELY RANGE. /NEUMAN

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES THROUGH THIS EVENING. THE
FLOW PATTERN WILL CONTINUE TO TURN ONSHORE THIS AFTERNOON AS A
WEAK FRONT APPROACHES THE REGION ALLOWING MARINE STRATUS TO FILL
BACK IN ALONG THE COAST BETWEEN 00Z AND 03Z. EXPECT IFR CIGS
BETWEEN 500 AND 1000 FT AND REDUCED VSBY ALONG THE COAST THROUGH
LATE TUE MORNING. CLOUDS CONTINUE TO PUSH INLAND TONIGHT...WITH
INTERIOR SITE LIKELY SEEING MVFR CIGS BETWEEN 1500 AND 2000 FT BY
15Z. CONDITIONS TURN VFR UNDER MOSTLY CLOUDY SKIES TUE AFTERNOON.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
LOWER CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AFFECTING THE
TERMINAL BY 14Z.

&&

.MARINE...A WEAK FRONT WILL MOVE ACROSS THE WATERS TOMORROW
MORNING BRINGING GUSTY NORTHWESTERLY WINDS AND BUILDING SEAS.
EXPECT GUSTS TO 35 KT AND SEAS AROUND 11 FT FROM TUE MORNING TO
WED. HIGH PRES BRIEFLY RETURNS WED AFTERNOON BEFORE ANOTHER WEAK
FRONT MOVES ACROSS THE WATERS ON THU. NOT EXPECTING MUCH IN THE
WAY OF IMPACTS WITH THIS SECOND FRONT. A MUCH STRONGER FRONT LOOKS
TO MOVE ACROSS THE WATERS OVER THE WEEKEND AND WILL LIKELY BRING
GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING SEAS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM TUESDAY TO NOON PDT
     WEDNESDAY FOR WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR
     FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM TUESDAY TO 6
     PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM TUESDAY TO NOON PDT
     WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM
     TO 10 AM PDT WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 202156
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
236 PM PDT MON APR 20 2015

.SYNOPSIS...INCREASING ONSHORE FLOW WILL LEAD TO NEAR AVERAGE
TEMPERATURES AND AN INCREASE IN MARINE CLOUDS TUESDAY THROUGH FRIDAY.
THERE WILL BE A SMALL CHANCE OF A SHOWER EACH DAY DURING THIS
PERIOD...PARTICULARLY ALONG THE COAST AND CASCADES...BUT MOST
LOCATIONS WILL GENERALLY REMAIN DRY. A WETTER PATTERN LOOKS TO
DEVELOP LATE SATURDAY AND SUNDAY...WITH PERHAPS ANOTHER ROUND OF WET
WEATHER EARLY NEXT WEEK.

&&

.SHORT TERM...VISIBLE SATELLITE IMAGERY REVEALS MAINLY CLEAR SKIES
ACROSS THE AREA EXCEPT FOR SOME LOW CLOUDS SKIRTING THE COASTLINE
UNDER LOW LEVEL NORTHERLY FLOW. SURFACE LOW PRESSURE IS SHIFTING
INLAND THIS AFTERNOON...WHICH WILL RESULT IN LOW CLOUDS PUSHING INTO
THE COAST RANGE GAPS THIS EVENING...AND PERHAPS A BRIEF SURGE OF
WESTERLY WINDS. LOW CLOUDS SHOULD SPREAD INTO THE WILLAMETTE VALLEY
OVERNIGHT AND TUESDAY MORNING...BUT DUE TO THE SHALLOW NATURE OF THE
THIS MARINE PUSH...THE CURRENT CLOUD COVER FORECAST IN THE WILLAMETTE
VALLEY MAY BE A BIT TOO PESSIMISTIC...ESPECIALLY ACROSS THE SOUTHERN
AND WESTERN PORTIONS OF THE VALLEY.

TEMPERATURES ON TUESDAY SHOULD TOP OUT APPROXIMATELY 10F COOLER THAN
TODAY DUE TO THE MUCH STRONGER MARINE INFLUENCE EXPECTED IN THE
WILLAMETTE VALLEY. ONSHORE PRESSURE GRADIENTS LOOK TO INCREASE
FURTHER TUESDAY AFTERNOON AND EVENING SO EXPECT BREEZY CONDITIONS TO
DEVELOP...ESPECIALLY NEAR THE COAST RANGE GAPS AND CENTRAL COLUMBIA
RIVER GORGE IN THE LATE AFTERNOON AND EVENING HOURS.

SHALLOW INSTABILITY AND MOISTURE MAY PRODUCE A FEW VERY LIGHT SHOWERS
TUESDAY NIGHT INTO EARLY WEDNESDAY...PARTICULARLY ACROSS THE NORTH
AND IN THE UPSLOPE AREAS...BUT CONFIDENCE IS LOW. A WEAKENING FRONT
MAY BRING INCREASING LIGHT RAIN CHANCES TO OUR FAR NORTHWEST ZONES
ON THURSDAY. ALL IN ALL...MOST LOCATIONS LOOK TO REMAIN GENERALLY
DRY THE NEXT FEW DAYS WITH TEMPERATURES TOPPING OUT NEAR AVERAGE.
/NEUMAN

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO
STRUGGLE ON THE DETAILS...BUT SUGGEST ONSHORE FLOW WILL CONTINUE NEAR
AVERAGE TEMPERATURES WITH A CHANCE FOR SOME LIGHT SHOWERS THURSDAY
NIGHT AND FRIDAY. WHILE MODELS DIFFER ON TIMING...BUT THE GFS AND EC
SUGGEST A WETTER FRONTAL STORM SYSTEM WILL SLOWLY SAG SOUTHWARD
ACROSS THE AREA LATE SATURDAY THROUGH SUNDAY NIGHT. AS A
RESULT...POPS WERE INCREASED IN THE LIKELY TO CATEGORICAL RANGE FOR
THE PRIME WINDOW OF SATURDAY NIGHT AND SUNDAY. BOTH MODELS SUGGEST
ANOTHER STORM SYSTEM IS LIKELY NEXT WEEK...BUT ONCE AGAIN DIFFER ON
TIMING SO POPS WERE TRENDED MORE INTO THE HIGH END CHANCE TO LOW END
LIKELY RANGE. /NEUMAN

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES THROUGH THIS EVENING. THE
FLOW PATTERN WILL CONTINUE TO TURN ONSHORE THIS AFTERNOON AS A
WEAK FRONT APPROACHES THE REGION ALLOWING MARINE STRATUS TO FILL
BACK IN ALONG THE COAST BETWEEN 00Z AND 03Z. EXPECT IFR CIGS
BETWEEN 500 AND 1000 FT AND REDUCED VSBY ALONG THE COAST THROUGH
LATE TUE MORNING. CLOUDS CONTINUE TO PUSH INLAND TONIGHT...WITH
INTERIOR SITE LIKELY SEEING MVFR CIGS BETWEEN 1500 AND 2000 FT BY
15Z. CONDITIONS TURN VFR UNDER MOSTLY CLOUDY SKIES TUE AFTERNOON.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
LOWER CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AFFECTING THE
TERMINAL BY 14Z.

&&

.MARINE...A WEAK FRONT WILL MOVE ACROSS THE WATERS TOMORROW
MORNING BRINGING GUSTY NORTHWESTERLY WINDS AND BUILDING SEAS.
EXPECT GUSTS TO 35 KT AND SEAS AROUND 11 FT FROM TUE MORNING TO
WED. HIGH PRES BRIEFLY RETURNS WED AFTERNOON BEFORE ANOTHER WEAK
FRONT MOVES ACROSS THE WATERS ON THU. NOT EXPECTING MUCH IN THE
WAY OF IMPACTS WITH THIS SECOND FRONT. A MUCH STRONGER FRONT LOOKS
TO MOVE ACROSS THE WATERS OVER THE WEEKEND AND WILL LIKELY BRING
GUSTY SOUTHERLY WINDS AND ANOTHER ROUND OF BUILDING SEAS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM TUESDAY TO NOON PDT
     WEDNESDAY FOR WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR
     FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM TUESDAY TO 6
     PM PDT WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 1 PM TUESDAY TO NOON PDT
     WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM
     TO 10 AM PDT WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KOTX 202143
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 PM PDT MON APR 20 2015

.SYNOPSIS...

Tuesday will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday.

&&

.DISCUSSION...

Tonight through Tuesday night...The axis of the ridge of high
pressure influencing the area moves east tomorrow. It does this at
slow enough of a speed to allow for temperatures of the seven day
forecast to peak for most locations tomorrow. Late in the
afternoon and evening with the axis to the east a weak marine push
of sorts allows for winds to increase in the gaps of the cascades
and close proximity to them late Tuesday afternoon and overnight.
The weak push may also fire off a bit of spotty convective showers
and perhaps a thunderstorm or two. Minimum temperatures Tuesday
night should be on the warm side of normal given the mixing
brought about by the wind. /Pelatti

Wednesday: Cooler and breezy weather will arrive Tuesday night
into Wednesday. The high amplitude 500mb ridge responsible for our
recent warm weather will be replaced by a cool polar low
descending out of the Gulf of Alaska. A relatively high spread in
model solutions continues for a day 3 forecast leading to lower
than average confidence for precipitation chances and winds for
Wednesday. The GFS model continues to be an outlier digging an
upper low deeper south into Washington on Wednesday. The ECMWF,
Canadian and NAM models look to have a more reasonable progressive
solution. The deeper/slower low on GFS looks a bit suspect given
the strong upstream kicker in the Gulf of Alaska, so the forecast
for Wednesday and Thursday was largely based on the Canadian
which is a compromise between the ECMWF and NAM.

This Canadian compromise means less chance for thunderstorms since
the heart of the 500mb cold pool will only graze the northern
Washington zones. This solution also entrains a good deal of mid-
level dry air into the region on Wednesday limiting the amount of
deep layer instability. Precipitation chances region-wide don`t
look very impressive. The Canadian and ECMWF solutions are a bit
breezier, so winds have been increased. We will likely see a 10
to 12 degree cool down from Tuesday into Wednesday as chilly
maritime air is squeezed through the gaps in the Cascades. The
change in air mass will likely be accompanied by typical breezy
spring time winds between 15 and 20 mph with some wind prone areas
in the lee of the Cascades gusting in excess of 30 mph on
Wednesday.

Thursday: If we discount the GFS, Thursday has the potential to be
a relatively dry day with fairly light winds. Precipitation
chances have been trimmed, limited to 20 percent or less in the
mountainous. Light winds and a good chance for mainly clear skies
suggest a fairly chilly morning on Thursday. Sheltered areas in
the Idaho Panhandle and northeast Washington will have a good shot
at low to mid 30s...perhaps a frost.

Friday and Saturday: By Friday, the main longwave trough over the
Gulf of Alaska is expected to move into Washington or southern
British Columbia. Seasonably chilly temperatures and showers will
likely accompany the arrival of this broad polar trough. Our
temperature forecast for Friday into Saturday has been cooled in
line with MOS guidance.

Sunday and Monday: Given the model uncertainty in the Wednesday
through Saturday time frame, it is a bit unusual to see the GFS,
ECMWF, and Canadian come into better agreement early next week.
The model consensus is for a mild and wet pattern Sunday and
Monday as a subtropical moisture plume becomes planted over the
Pacific Northwest. Early next week looks like our best shot of
widespread precipitation during the next 7 to 10 day period.
/GKoch

&&

.AVIATION...
18Z TAFS: VFR condtions to prevail as high pressure allows minor
mid and high clouds to stream overhead of TAF sites. /Pelatti


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        46  74  50  61  36  62 /   0  10  10  20  10  10
Coeur d`Alene  41  73  44  62  34  62 /   0  10  10  20  20  10
Pullman        42  72  46  58  34  61 /   0  10  10  30  10  10
Lewiston       46  78  49  65  38  66 /   0   0  10  30  10  10
Colville       42  77  46  65  37  65 /   0  10  10  40  40  20
Sandpoint      38  72  40  61  33  60 /   0  10  10  30  30  20
Kellogg        40  71  43  59  34  62 /   0  10  10  30  20  20
Moses Lake     44  78  50  67  37  66 /   0  10  10  10   0  10
Wenatchee      51  77  53  65  41  65 /   0  10  10  10   0  10
Omak           44  77  47  65  35  64 /   0  10  10  30  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 202143
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 PM PDT MON APR 20 2015

.SYNOPSIS...

Tuesday will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday.

&&

.DISCUSSION...

Tonight through Tuesday night...The axis of the ridge of high
pressure influencing the area moves east tomorrow. It does this at
slow enough of a speed to allow for temperatures of the seven day
forecast to peak for most locations tomorrow. Late in the
afternoon and evening with the axis to the east a weak marine push
of sorts allows for winds to increase in the gaps of the cascades
and close proximity to them late Tuesday afternoon and overnight.
The weak push may also fire off a bit of spotty convective showers
and perhaps a thunderstorm or two. Minimum temperatures Tuesday
night should be on the warm side of normal given the mixing
brought about by the wind. /Pelatti

Wednesday: Cooler and breezy weather will arrive Tuesday night
into Wednesday. The high amplitude 500mb ridge responsible for our
recent warm weather will be replaced by a cool polar low
descending out of the Gulf of Alaska. A relatively high spread in
model solutions continues for a day 3 forecast leading to lower
than average confidence for precipitation chances and winds for
Wednesday. The GFS model continues to be an outlier digging an
upper low deeper south into Washington on Wednesday. The ECMWF,
Canadian and NAM models look to have a more reasonable progressive
solution. The deeper/slower low on GFS looks a bit suspect given
the strong upstream kicker in the Gulf of Alaska, so the forecast
for Wednesday and Thursday was largely based on the Canadian
which is a compromise between the ECMWF and NAM.

This Canadian compromise means less chance for thunderstorms since
the heart of the 500mb cold pool will only graze the northern
Washington zones. This solution also entrains a good deal of mid-
level dry air into the region on Wednesday limiting the amount of
deep layer instability. Precipitation chances region-wide don`t
look very impressive. The Canadian and ECMWF solutions are a bit
breezier, so winds have been increased. We will likely see a 10
to 12 degree cool down from Tuesday into Wednesday as chilly
maritime air is squeezed through the gaps in the Cascades. The
change in air mass will likely be accompanied by typical breezy
spring time winds between 15 and 20 mph with some wind prone areas
in the lee of the Cascades gusting in excess of 30 mph on
Wednesday.

Thursday: If we discount the GFS, Thursday has the potential to be
a relatively dry day with fairly light winds. Precipitation
chances have been trimmed, limited to 20 percent or less in the
mountainous. Light winds and a good chance for mainly clear skies
suggest a fairly chilly morning on Thursday. Sheltered areas in
the Idaho Panhandle and northeast Washington will have a good shot
at low to mid 30s...perhaps a frost.

Friday and Saturday: By Friday, the main longwave trough over the
Gulf of Alaska is expected to move into Washington or southern
British Columbia. Seasonably chilly temperatures and showers will
likely accompany the arrival of this broad polar trough. Our
temperature forecast for Friday into Saturday has been cooled in
line with MOS guidance.

Sunday and Monday: Given the model uncertainty in the Wednesday
through Saturday time frame, it is a bit unusual to see the GFS,
ECMWF, and Canadian come into better agreement early next week.
The model consensus is for a mild and wet pattern Sunday and
Monday as a subtropical moisture plume becomes planted over the
Pacific Northwest. Early next week looks like our best shot of
widespread precipitation during the next 7 to 10 day period.
/GKoch

&&

.AVIATION...
18Z TAFS: VFR condtions to prevail as high pressure allows minor
mid and high clouds to stream overhead of TAF sites. /Pelatti


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        46  74  50  61  36  62 /   0  10  10  20  10  10
Coeur d`Alene  41  73  44  62  34  62 /   0  10  10  20  20  10
Pullman        42  72  46  58  34  61 /   0  10  10  30  10  10
Lewiston       46  78  49  65  38  66 /   0   0  10  30  10  10
Colville       42  77  46  65  37  65 /   0  10  10  40  40  20
Sandpoint      38  72  40  61  33  60 /   0  10  10  30  30  20
Kellogg        40  71  43  59  34  62 /   0  10  10  30  20  20
Moses Lake     44  78  50  67  37  66 /   0  10  10  10   0  10
Wenatchee      51  77  53  65  41  65 /   0  10  10  10   0  10
Omak           44  77  47  65  35  64 /   0  10  10  30  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 202143
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 PM PDT MON APR 20 2015

.SYNOPSIS...

Tuesday will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday.

&&

.DISCUSSION...

Tonight through Tuesday night...The axis of the ridge of high
pressure influencing the area moves east tomorrow. It does this at
slow enough of a speed to allow for temperatures of the seven day
forecast to peak for most locations tomorrow. Late in the
afternoon and evening with the axis to the east a weak marine push
of sorts allows for winds to increase in the gaps of the cascades
and close proximity to them late Tuesday afternoon and overnight.
The weak push may also fire off a bit of spotty convective showers
and perhaps a thunderstorm or two. Minimum temperatures Tuesday
night should be on the warm side of normal given the mixing
brought about by the wind. /Pelatti

Wednesday: Cooler and breezy weather will arrive Tuesday night
into Wednesday. The high amplitude 500mb ridge responsible for our
recent warm weather will be replaced by a cool polar low
descending out of the Gulf of Alaska. A relatively high spread in
model solutions continues for a day 3 forecast leading to lower
than average confidence for precipitation chances and winds for
Wednesday. The GFS model continues to be an outlier digging an
upper low deeper south into Washington on Wednesday. The ECMWF,
Canadian and NAM models look to have a more reasonable progressive
solution. The deeper/slower low on GFS looks a bit suspect given
the strong upstream kicker in the Gulf of Alaska, so the forecast
for Wednesday and Thursday was largely based on the Canadian
which is a compromise between the ECMWF and NAM.

This Canadian compromise means less chance for thunderstorms since
the heart of the 500mb cold pool will only graze the northern
Washington zones. This solution also entrains a good deal of mid-
level dry air into the region on Wednesday limiting the amount of
deep layer instability. Precipitation chances region-wide don`t
look very impressive. The Canadian and ECMWF solutions are a bit
breezier, so winds have been increased. We will likely see a 10
to 12 degree cool down from Tuesday into Wednesday as chilly
maritime air is squeezed through the gaps in the Cascades. The
change in air mass will likely be accompanied by typical breezy
spring time winds between 15 and 20 mph with some wind prone areas
in the lee of the Cascades gusting in excess of 30 mph on
Wednesday.

Thursday: If we discount the GFS, Thursday has the potential to be
a relatively dry day with fairly light winds. Precipitation
chances have been trimmed, limited to 20 percent or less in the
mountainous. Light winds and a good chance for mainly clear skies
suggest a fairly chilly morning on Thursday. Sheltered areas in
the Idaho Panhandle and northeast Washington will have a good shot
at low to mid 30s...perhaps a frost.

Friday and Saturday: By Friday, the main longwave trough over the
Gulf of Alaska is expected to move into Washington or southern
British Columbia. Seasonably chilly temperatures and showers will
likely accompany the arrival of this broad polar trough. Our
temperature forecast for Friday into Saturday has been cooled in
line with MOS guidance.

Sunday and Monday: Given the model uncertainty in the Wednesday
through Saturday time frame, it is a bit unusual to see the GFS,
ECMWF, and Canadian come into better agreement early next week.
The model consensus is for a mild and wet pattern Sunday and
Monday as a subtropical moisture plume becomes planted over the
Pacific Northwest. Early next week looks like our best shot of
widespread precipitation during the next 7 to 10 day period.
/GKoch

&&

.AVIATION...
18Z TAFS: VFR condtions to prevail as high pressure allows minor
mid and high clouds to stream overhead of TAF sites. /Pelatti


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        46  74  50  61  36  62 /   0  10  10  20  10  10
Coeur d`Alene  41  73  44  62  34  62 /   0  10  10  20  20  10
Pullman        42  72  46  58  34  61 /   0  10  10  30  10  10
Lewiston       46  78  49  65  38  66 /   0   0  10  30  10  10
Colville       42  77  46  65  37  65 /   0  10  10  40  40  20
Sandpoint      38  72  40  61  33  60 /   0  10  10  30  30  20
Kellogg        40  71  43  59  34  62 /   0  10  10  30  20  20
Moses Lake     44  78  50  67  37  66 /   0  10  10  10   0  10
Wenatchee      51  77  53  65  41  65 /   0  10  10  10   0  10
Omak           44  77  47  65  35  64 /   0  10  10  30  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 202143
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 PM PDT MON APR 20 2015

.SYNOPSIS...

Tuesday will likely be the warmest day in the next 7 to 10 days as
strong high pressure remains over the region for one last day. A
cold front will arrive Tuesday night bringing cooler weather and
breezy conditions into Wednesday. A cool upper trough is expected
to bring showery conditions Friday and Saturday.

&&

.DISCUSSION...

Tonight through Tuesday night...The axis of the ridge of high
pressure influencing the area moves east tomorrow. It does this at
slow enough of a speed to allow for temperatures of the seven day
forecast to peak for most locations tomorrow. Late in the
afternoon and evening with the axis to the east a weak marine push
of sorts allows for winds to increase in the gaps of the cascades
and close proximity to them late Tuesday afternoon and overnight.
The weak push may also fire off a bit of spotty convective showers
and perhaps a thunderstorm or two. Minimum temperatures Tuesday
night should be on the warm side of normal given the mixing
brought about by the wind. /Pelatti

Wednesday: Cooler and breezy weather will arrive Tuesday night
into Wednesday. The high amplitude 500mb ridge responsible for our
recent warm weather will be replaced by a cool polar low
descending out of the Gulf of Alaska. A relatively high spread in
model solutions continues for a day 3 forecast leading to lower
than average confidence for precipitation chances and winds for
Wednesday. The GFS model continues to be an outlier digging an
upper low deeper south into Washington on Wednesday. The ECMWF,
Canadian and NAM models look to have a more reasonable progressive
solution. The deeper/slower low on GFS looks a bit suspect given
the strong upstream kicker in the Gulf of Alaska, so the forecast
for Wednesday and Thursday was largely based on the Canadian
which is a compromise between the ECMWF and NAM.

This Canadian compromise means less chance for thunderstorms since
the heart of the 500mb cold pool will only graze the northern
Washington zones. This solution also entrains a good deal of mid-
level dry air into the region on Wednesday limiting the amount of
deep layer instability. Precipitation chances region-wide don`t
look very impressive. The Canadian and ECMWF solutions are a bit
breezier, so winds have been increased. We will likely see a 10
to 12 degree cool down from Tuesday into Wednesday as chilly
maritime air is squeezed through the gaps in the Cascades. The
change in air mass will likely be accompanied by typical breezy
spring time winds between 15 and 20 mph with some wind prone areas
in the lee of the Cascades gusting in excess of 30 mph on
Wednesday.

Thursday: If we discount the GFS, Thursday has the potential to be
a relatively dry day with fairly light winds. Precipitation
chances have been trimmed, limited to 20 percent or less in the
mountainous. Light winds and a good chance for mainly clear skies
suggest a fairly chilly morning on Thursday. Sheltered areas in
the Idaho Panhandle and northeast Washington will have a good shot
at low to mid 30s...perhaps a frost.

Friday and Saturday: By Friday, the main longwave trough over the
Gulf of Alaska is expected to move into Washington or southern
British Columbia. Seasonably chilly temperatures and showers will
likely accompany the arrival of this broad polar trough. Our
temperature forecast for Friday into Saturday has been cooled in
line with MOS guidance.

Sunday and Monday: Given the model uncertainty in the Wednesday
through Saturday time frame, it is a bit unusual to see the GFS,
ECMWF, and Canadian come into better agreement early next week.
The model consensus is for a mild and wet pattern Sunday and
Monday as a subtropical moisture plume becomes planted over the
Pacific Northwest. Early next week looks like our best shot of
widespread precipitation during the next 7 to 10 day period.
/GKoch

&&

.AVIATION...
18Z TAFS: VFR condtions to prevail as high pressure allows minor
mid and high clouds to stream overhead of TAF sites. /Pelatti


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        46  74  50  61  36  62 /   0  10  10  20  10  10
Coeur d`Alene  41  73  44  62  34  62 /   0  10  10  20  20  10
Pullman        42  72  46  58  34  61 /   0  10  10  30  10  10
Lewiston       46  78  49  65  38  66 /   0   0  10  30  10  10
Colville       42  77  46  65  37  65 /   0  10  10  40  40  20
Sandpoint      38  72  40  61  33  60 /   0  10  10  30  30  20
Kellogg        40  71  43  59  34  62 /   0  10  10  30  20  20
Moses Lake     44  78  50  67  37  66 /   0  10  10  10   0  10
Wenatchee      51  77  53  65  41  65 /   0  10  10  10   0  10
Omak           44  77  47  65  35  64 /   0  10  10  30  20  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 201731
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1031 AM PDT MON APR 20 2015

.SYNOPSIS...

High pressure will allow for warm and above average temperatures
over Eastern Washington and Northern Idaho through Tuesday. This
will be interrupted by a cold front passage Wednesday allowing for
cooler and potentially wetter and gusty conditions. These cooler
and potentially somewhat wet and unsettled conditions linger on
through the remainder of the week.

&&

.DISCUSSION...
Minor updates to sky cover and temperatures this morning.
Additionally increased some of the wind and wind gusts expected
with the cold front passage Wednesday. /Pelatti

&&

.AVIATION...
18Z TAFS: VFR condtions to prevail as high pressure allows minor
mid and high clouds to stream overhead of TAF sites. /Pelatti

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        72  46  75  50  65  41 /   0   0  10  10  20  30
Coeur d`Alene  70  41  75  44  65  41 /   0   0  10  10  30  30
Pullman        69  42  74  46  64  39 /   0   0  10  10  20  20
Lewiston       76  46  78  49  70  43 /   0   0   0  10  20  20
Colville       75  42  77  46  68  43 /   0   0  10  10  40  30
Sandpoint      69  38  73  40  67  39 /   0   0  10  10  40  40
Kellogg        68  40  74  43  67  39 /   0   0  10  10  40  30
Moses Lake     77  44  78  50  67  41 /   0   0  10  10  20  10
Wenatchee      77  51  77  53  66  43 /   0   0  10  10  20  10
Omak           77  44  77  47  66  40 /   0   0  10  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KOTX 201731
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1031 AM PDT MON APR 20 2015

.SYNOPSIS...

High pressure will allow for warm and above average temperatures
over Eastern Washington and Northern Idaho through Tuesday. This
will be interrupted by a cold front passage Wednesday allowing for
cooler and potentially wetter and gusty conditions. These cooler
and potentially somewhat wet and unsettled conditions linger on
through the remainder of the week.

&&

.DISCUSSION...
Minor updates to sky cover and temperatures this morning.
Additionally increased some of the wind and wind gusts expected
with the cold front passage Wednesday. /Pelatti

&&

.AVIATION...
18Z TAFS: VFR condtions to prevail as high pressure allows minor
mid and high clouds to stream overhead of TAF sites. /Pelatti

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        72  46  75  50  65  41 /   0   0  10  10  20  30
Coeur d`Alene  70  41  75  44  65  41 /   0   0  10  10  30  30
Pullman        69  42  74  46  64  39 /   0   0  10  10  20  20
Lewiston       76  46  78  49  70  43 /   0   0   0  10  20  20
Colville       75  42  77  46  68  43 /   0   0  10  10  40  30
Sandpoint      69  38  73  40  67  39 /   0   0  10  10  40  40
Kellogg        68  40  74  43  67  39 /   0   0  10  10  40  30
Moses Lake     77  44  78  50  67  41 /   0   0  10  10  20  10
Wenatchee      77  51  77  53  66  43 /   0   0  10  10  20  10
Omak           77  44  77  47  66  40 /   0   0  10  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$





000
FXUS66 KSEW 201618
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
915 AM PDT MON APR 20 2015

.SYNOPSIS...A WARM SUNNY DAY TODAY WILL BE FOLLOWED BY COOL MARINE
AIR PUSHING INTO WESTERN WASHINGTON TONIGHT AND TUESDAY. AN UPPER
TROUGH WILL BRING INCREASING SHOWERS TO THE AREA TUESDAY AND
WEDNESDAY. A FRONT WILL ARRIVE LATER THURSDAY. STRONGER FRONTS ARE
LIKELY TO ARRIVE NEXT WEEKEND.

&&

.SHORT TERM...THE RIDGE IS WEAKENING AND WILL MOVE SLOWLY INLAND
THROUGH TUESDAY. A STRETCHED OUT UPPER TROUGH CROSSES 130W TODAY...
SPLITS APART SOME MORE...AND THEN THE NORTHERN PORTION OF THE TROUGH
MOVES OVER WESTERN WA TUESDAY NIGHT. THE TROUGH EVOLVES INTO MORE OF
A CLOSED UPPER LOW WEDNESDAY...MOVING TO EASTERN WA BY WEDNESDAY
EVENING. MEANWHILE...ANOTHER UPPER TROUGH MOVES INTO THE NE PACIFIC
AND AN ASSOCIATED COLD FRONT REACHES WRN WA AROUND THU AFTERNOON.

.LONG TERM...AFTER THE COLD FRONT AND ITS ASSOCIATED UPPER TROUGH
MOVE INLAND THU NITE THERE WILL BE A BRIEF PERIOD OF WEAK RIDGING
THROUGH FRI NITE. SEVERAL FRONTAL WAVES ARE LIKELY FROM NEXT WEEKEND
INTO THE LAST FEW DAYS OF APRIL WHILE A LARGE UPPER TROUGH TAKES
UP RESIDENCE IN THE NE PACIFIC.

&&

.AVIATION...AN UPPER LEVEL RIDGE OVER THE PACIFIC NORTHWEST WILL
LEAD TO DRY AND STABLE WEATHER ACROSS WESTERN WASHINGTON TODAY. THE
FLOW ALOFT IS WESTERLY. VFR CONDITIONS ARE EXPECTED. SKIES WILL
REMAIN MOSTLY CLEAR WITH JUST FEW-SCT CIRRUS ALOFT. A MARINE PUSH
WILL BRING LOW CLOUDS TO THE COAST THIS EVENING WITH STRATUS MOVING
INTO THE INTERIOR EARLY TUESDAY...WITH MVFR TO IFR CEILINGS LIKELY.

KSEA...NORTH WIND TO 10 KT. LOW LEVEL MARINE CLOUDS WILL PUSH INLAND
LATE TONIGHT OR EARLY TUESDAY MORNING WITH MVFR TO IFR CEILINGS
LIKELY.   MCDONNAL

&&

.MARINE...ONSHORE FLOW WILL STRENGTHEN TODAY AND TONIGHT AS LOW
PRESSURE ALONG THE COAST SHIFTS INLAND. SMALL CRAFT ADVISORY
WESTERLIES ARE LIKELY IN THE CENTRAL AND EASTERN STRAIT OF JUAN DE
FUCA...ADMIRALTY INLET...AND NORTHERN INLAND WATERS.

ONSHORE FLOW WILL INCREASE FURTHER ON TUESDAY AS A COLD FRONT MOVES
INLAND...THEN CONTINUE THROUGH WEDNESDAY. WESTERLIES GALES ARE VERY
LIKELY IN THE CENTRAL AND EASTERN STRAIT OF JUAN DE FUCA TUESDAY
NIGHT...AND LIKELY IN THE NORTHWEST PART OF THE COASTAL WATERS AS
WELL. A GALE WATCH HAS BEEN ISSUED FOR THESE ZONES.

ANOTHER COLD FRONT WILL CROSS THE AREA LATE WEDNESDAY NIGHT OR
THURSDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY CENTRAL AND EASTERN STRAIT OF JUAN DE
       FUCA...ADMIRALTY INLET...NORTHERN INLAND WATERS.
    .GALE WATCH COASTAL WATERS ZONES 150 170 173...CENTRAL AND
       EASTERN STRAIT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML





000
FXUS66 KSEW 201618
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
915 AM PDT MON APR 20 2015

.SYNOPSIS...A WARM SUNNY DAY TODAY WILL BE FOLLOWED BY COOL MARINE
AIR PUSHING INTO WESTERN WASHINGTON TONIGHT AND TUESDAY. AN UPPER
TROUGH WILL BRING INCREASING SHOWERS TO THE AREA TUESDAY AND
WEDNESDAY. A FRONT WILL ARRIVE LATER THURSDAY. STRONGER FRONTS ARE
LIKELY TO ARRIVE NEXT WEEKEND.

&&

.SHORT TERM...THE RIDGE IS WEAKENING AND WILL MOVE SLOWLY INLAND
THROUGH TUESDAY. A STRETCHED OUT UPPER TROUGH CROSSES 130W TODAY...
SPLITS APART SOME MORE...AND THEN THE NORTHERN PORTION OF THE TROUGH
MOVES OVER WESTERN WA TUESDAY NIGHT. THE TROUGH EVOLVES INTO MORE OF
A CLOSED UPPER LOW WEDNESDAY...MOVING TO EASTERN WA BY WEDNESDAY
EVENING. MEANWHILE...ANOTHER UPPER TROUGH MOVES INTO THE NE PACIFIC
AND AN ASSOCIATED COLD FRONT REACHES WRN WA AROUND THU AFTERNOON.

.LONG TERM...AFTER THE COLD FRONT AND ITS ASSOCIATED UPPER TROUGH
MOVE INLAND THU NITE THERE WILL BE A BRIEF PERIOD OF WEAK RIDGING
THROUGH FRI NITE. SEVERAL FRONTAL WAVES ARE LIKELY FROM NEXT WEEKEND
INTO THE LAST FEW DAYS OF APRIL WHILE A LARGE UPPER TROUGH TAKES
UP RESIDENCE IN THE NE PACIFIC.

&&

.AVIATION...AN UPPER LEVEL RIDGE OVER THE PACIFIC NORTHWEST WILL
LEAD TO DRY AND STABLE WEATHER ACROSS WESTERN WASHINGTON TODAY. THE
FLOW ALOFT IS WESTERLY. VFR CONDITIONS ARE EXPECTED. SKIES WILL
REMAIN MOSTLY CLEAR WITH JUST FEW-SCT CIRRUS ALOFT. A MARINE PUSH
WILL BRING LOW CLOUDS TO THE COAST THIS EVENING WITH STRATUS MOVING
INTO THE INTERIOR EARLY TUESDAY...WITH MVFR TO IFR CEILINGS LIKELY.

KSEA...NORTH WIND TO 10 KT. LOW LEVEL MARINE CLOUDS WILL PUSH INLAND
LATE TONIGHT OR EARLY TUESDAY MORNING WITH MVFR TO IFR CEILINGS
LIKELY.   MCDONNAL

&&

.MARINE...ONSHORE FLOW WILL STRENGTHEN TODAY AND TONIGHT AS LOW
PRESSURE ALONG THE COAST SHIFTS INLAND. SMALL CRAFT ADVISORY
WESTERLIES ARE LIKELY IN THE CENTRAL AND EASTERN STRAIT OF JUAN DE
FUCA...ADMIRALTY INLET...AND NORTHERN INLAND WATERS.

ONSHORE FLOW WILL INCREASE FURTHER ON TUESDAY AS A COLD FRONT MOVES
INLAND...THEN CONTINUE THROUGH WEDNESDAY. WESTERLIES GALES ARE VERY
LIKELY IN THE CENTRAL AND EASTERN STRAIT OF JUAN DE FUCA TUESDAY
NIGHT...AND LIKELY IN THE NORTHWEST PART OF THE COASTAL WATERS AS
WELL. A GALE WATCH HAS BEEN ISSUED FOR THESE ZONES.

ANOTHER COLD FRONT WILL CROSS THE AREA LATE WEDNESDAY NIGHT OR
THURSDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY CENTRAL AND EASTERN STRAIT OF JUAN DE
       FUCA...ADMIRALTY INLET...NORTHERN INLAND WATERS.
    .GALE WATCH COASTAL WATERS ZONES 150 170 173...CENTRAL AND
       EASTERN STRAIT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML





000
FXUS66 KSEW 201618
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
915 AM PDT MON APR 20 2015

.SYNOPSIS...A WARM SUNNY DAY TODAY WILL BE FOLLOWED BY COOL MARINE
AIR PUSHING INTO WESTERN WASHINGTON TONIGHT AND TUESDAY. AN UPPER
TROUGH WILL BRING INCREASING SHOWERS TO THE AREA TUESDAY AND
WEDNESDAY. A FRONT WILL ARRIVE LATER THURSDAY. STRONGER FRONTS ARE
LIKELY TO ARRIVE NEXT WEEKEND.

&&

.SHORT TERM...THE RIDGE IS WEAKENING AND WILL MOVE SLOWLY INLAND
THROUGH TUESDAY. A STRETCHED OUT UPPER TROUGH CROSSES 130W TODAY...
SPLITS APART SOME MORE...AND THEN THE NORTHERN PORTION OF THE TROUGH
MOVES OVER WESTERN WA TUESDAY NIGHT. THE TROUGH EVOLVES INTO MORE OF
A CLOSED UPPER LOW WEDNESDAY...MOVING TO EASTERN WA BY WEDNESDAY
EVENING. MEANWHILE...ANOTHER UPPER TROUGH MOVES INTO THE NE PACIFIC
AND AN ASSOCIATED COLD FRONT REACHES WRN WA AROUND THU AFTERNOON.

.LONG TERM...AFTER THE COLD FRONT AND ITS ASSOCIATED UPPER TROUGH
MOVE INLAND THU NITE THERE WILL BE A BRIEF PERIOD OF WEAK RIDGING
THROUGH FRI NITE. SEVERAL FRONTAL WAVES ARE LIKELY FROM NEXT WEEKEND
INTO THE LAST FEW DAYS OF APRIL WHILE A LARGE UPPER TROUGH TAKES
UP RESIDENCE IN THE NE PACIFIC.

&&

.AVIATION...AN UPPER LEVEL RIDGE OVER THE PACIFIC NORTHWEST WILL
LEAD TO DRY AND STABLE WEATHER ACROSS WESTERN WASHINGTON TODAY. THE
FLOW ALOFT IS WESTERLY. VFR CONDITIONS ARE EXPECTED. SKIES WILL
REMAIN MOSTLY CLEAR WITH JUST FEW-SCT CIRRUS ALOFT. A MARINE PUSH
WILL BRING LOW CLOUDS TO THE COAST THIS EVENING WITH STRATUS MOVING
INTO THE INTERIOR EARLY TUESDAY...WITH MVFR TO IFR CEILINGS LIKELY.

KSEA...NORTH WIND TO 10 KT. LOW LEVEL MARINE CLOUDS WILL PUSH INLAND
LATE TONIGHT OR EARLY TUESDAY MORNING WITH MVFR TO IFR CEILINGS
LIKELY.   MCDONNAL

&&

.MARINE...ONSHORE FLOW WILL STRENGTHEN TODAY AND TONIGHT AS LOW
PRESSURE ALONG THE COAST SHIFTS INLAND. SMALL CRAFT ADVISORY
WESTERLIES ARE LIKELY IN THE CENTRAL AND EASTERN STRAIT OF JUAN DE
FUCA...ADMIRALTY INLET...AND NORTHERN INLAND WATERS.

ONSHORE FLOW WILL INCREASE FURTHER ON TUESDAY AS A COLD FRONT MOVES
INLAND...THEN CONTINUE THROUGH WEDNESDAY. WESTERLIES GALES ARE VERY
LIKELY IN THE CENTRAL AND EASTERN STRAIT OF JUAN DE FUCA TUESDAY
NIGHT...AND LIKELY IN THE NORTHWEST PART OF THE COASTAL WATERS AS
WELL. A GALE WATCH HAS BEEN ISSUED FOR THESE ZONES.

ANOTHER COLD FRONT WILL CROSS THE AREA LATE WEDNESDAY NIGHT OR
THURSDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY CENTRAL AND EASTERN STRAIT OF JUAN DE
       FUCA...ADMIRALTY INLET...NORTHERN INLAND WATERS.
    .GALE WATCH COASTAL WATERS ZONES 150 170 173...CENTRAL AND
       EASTERN STRAIT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML





000
FXUS66 KSEW 201618
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
915 AM PDT MON APR 20 2015

.SYNOPSIS...A WARM SUNNY DAY TODAY WILL BE FOLLOWED BY COOL MARINE
AIR PUSHING INTO WESTERN WASHINGTON TONIGHT AND TUESDAY. AN UPPER
TROUGH WILL BRING INCREASING SHOWERS TO THE AREA TUESDAY AND
WEDNESDAY. A FRONT WILL ARRIVE LATER THURSDAY. STRONGER FRONTS ARE
LIKELY TO ARRIVE NEXT WEEKEND.

&&

.SHORT TERM...THE RIDGE IS WEAKENING AND WILL MOVE SLOWLY INLAND
THROUGH TUESDAY. A STRETCHED OUT UPPER TROUGH CROSSES 130W TODAY...
SPLITS APART SOME MORE...AND THEN THE NORTHERN PORTION OF THE TROUGH
MOVES OVER WESTERN WA TUESDAY NIGHT. THE TROUGH EVOLVES INTO MORE OF
A CLOSED UPPER LOW WEDNESDAY...MOVING TO EASTERN WA BY WEDNESDAY
EVENING. MEANWHILE...ANOTHER UPPER TROUGH MOVES INTO THE NE PACIFIC
AND AN ASSOCIATED COLD FRONT REACHES WRN WA AROUND THU AFTERNOON.

.LONG TERM...AFTER THE COLD FRONT AND ITS ASSOCIATED UPPER TROUGH
MOVE INLAND THU NITE THERE WILL BE A BRIEF PERIOD OF WEAK RIDGING
THROUGH FRI NITE. SEVERAL FRONTAL WAVES ARE LIKELY FROM NEXT WEEKEND
INTO THE LAST FEW DAYS OF APRIL WHILE A LARGE UPPER TROUGH TAKES
UP RESIDENCE IN THE NE PACIFIC.

&&

.AVIATION...AN UPPER LEVEL RIDGE OVER THE PACIFIC NORTHWEST WILL
LEAD TO DRY AND STABLE WEATHER ACROSS WESTERN WASHINGTON TODAY. THE
FLOW ALOFT IS WESTERLY. VFR CONDITIONS ARE EXPECTED. SKIES WILL
REMAIN MOSTLY CLEAR WITH JUST FEW-SCT CIRRUS ALOFT. A MARINE PUSH
WILL BRING LOW CLOUDS TO THE COAST THIS EVENING WITH STRATUS MOVING
INTO THE INTERIOR EARLY TUESDAY...WITH MVFR TO IFR CEILINGS LIKELY.

KSEA...NORTH WIND TO 10 KT. LOW LEVEL MARINE CLOUDS WILL PUSH INLAND
LATE TONIGHT OR EARLY TUESDAY MORNING WITH MVFR TO IFR CEILINGS
LIKELY.   MCDONNAL

&&

.MARINE...ONSHORE FLOW WILL STRENGTHEN TODAY AND TONIGHT AS LOW
PRESSURE ALONG THE COAST SHIFTS INLAND. SMALL CRAFT ADVISORY
WESTERLIES ARE LIKELY IN THE CENTRAL AND EASTERN STRAIT OF JUAN DE
FUCA...ADMIRALTY INLET...AND NORTHERN INLAND WATERS.

ONSHORE FLOW WILL INCREASE FURTHER ON TUESDAY AS A COLD FRONT MOVES
INLAND...THEN CONTINUE THROUGH WEDNESDAY. WESTERLIES GALES ARE VERY
LIKELY IN THE CENTRAL AND EASTERN STRAIT OF JUAN DE FUCA TUESDAY
NIGHT...AND LIKELY IN THE NORTHWEST PART OF THE COASTAL WATERS AS
WELL. A GALE WATCH HAS BEEN ISSUED FOR THESE ZONES.

ANOTHER COLD FRONT WILL CROSS THE AREA LATE WEDNESDAY NIGHT OR
THURSDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY CENTRAL AND EASTERN STRAIT OF JUAN DE
       FUCA...ADMIRALTY INLET...NORTHERN INLAND WATERS.
    .GALE WATCH COASTAL WATERS ZONES 150 170 173...CENTRAL AND
       EASTERN STRAIT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML





000
FXUS66 KPQR 201603
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
858 AM PDT MON APR 20 2015

.SYNOPSIS...HIGH PRESSURE WILL CONTINUE TO PROVIDE UNSEASONABLY
WARM WEATHER TO THE PACIFIC NORTHWEST TODAY. THE RIDGE WILL SHIFT
INLAND TONIGHT AS AN UPPER TROUGH NEARS...ALLOWING A DEEPER MARINE
LAYER TO DEVELOP. THIS WILL BEGIN A SIGNIFICANT COOL DOWN FOR TUESDAY
AS LOW CLOUDS PUSH ONSHORE AHEAD OF A WEAK COLD FRONT. AN UPPER LEVEL
TROUGH WILL LINGER THROUGH THE END OF THE WEEK...KEEPING
TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL. A COOLER MORE SHOWERY
PATTERN MAY DEVELOP LATE IN THE WORK WEEK AND PERSIST THROUGH THE
WEEKEND.

&&

.SHORT TERM...VISIBLE SATELLITE IMAGERY REVEALS MAINLY CLEAR SKIES
ACROSS THE AREA EXCEPT FOR SOME FOG AND LOW STRATUS THAT HAS
DEVELOPED ALONG NEAR THE COAST OVERNIGHT UNDER NORTHERLY FLOW. A
THERMAL TROUGH CURRENTLY NEAR THE COAST WILL PUSH EAST OF THE
CASCADES LATER TODAY AND TONIGHT. THIS WILL ALLOW FOR COASTAL FOG
AND STRATUS TO PUSH INTO THE GAPS THIS EVENING AND INTO THE
WILLAMETTE VALLEY LATE TONIGHT AND TUESDAY MORNING. DUE TO LOW LEVEL
NORTHERLY FLOW...CLOUDS MAY HAVE A SOMEWHAT DIFFICULT TIME SPREADING
INTO THE ENTIRE WILLAMETTE VALLEY THOUGH.

NONETHELESS...THE INCREASE IN CLOUD COVER AND MARINE INFLUENCE AS A
WHOLE ACROSS THE REGION WILL RESULT IN MUCH COOLER HIGH TEMPERATURES
ON TUESDAY. A COLD FRONT AND ATTENDANT CLOUD COVER CURRENTLY VISIBLE
ON SATELLITE IMAGERY APPROACHING 130W WILL PUSH INTO THE PACIFIC
NORTHWEST LATE TUESDAY. AS THIS SYSTEM APPROACHES THE
REGION...ONSHORE PRESSURE GRADIENTS SHOULD INCREASE DRAMATICALLY SO
EXPECT BREEZY CONDITIONS TO DEVELOP LATE TUESDAY AFTERNOON AND
EVENING...ESPECIALLY NEAR THE COAST RANGE GAPS AND IN THE CENTRAL
COLUMBIA RIVER GORGE. THIS SHOULD ALSO RESULT IN MORE CLOUDS
SPREADING INLAND TUESDAY NIGHT AND AS A RESULT...WEDNESDAYS HIGH
TEMPERATURES SHOULD COOL EVEN FURTHER AND TOP OUT NEAR AVERAGE. HAVE
LEFT POPS IN TACT FOR TUESDAY AND WEDNESDAY...BUT ASIDE FROM A
CHANCE FOR SOME DRIZZLE...HIGHEST NEAR THE COAST...MOST LOCATIONS
LOOK TO REMAIN DRY DURING THIS PERIOD. WILL EVALUATE FURTHER WITH
THE AFTERNOON FORECAST PACKAGE. MODELS BEGIN TO DIFFER MORE
SUBSTANTIALLY ON THE STRENGTH OF A FRONTAL STORM SYSTEM AND
ATTENDANT UPPER LEVEL TROUGH ON THURSDAY SO NO CHANGES WERE MADE TO
THAT PORTION OF THE FORECAST YET. /NEUMAN


.LONG TERM...THURSDAY NIGHT THROUGH SUNDAY...PREVIOUS DISCUSSION
BELOW...MODELS ARE STRUGGLING WITH THE THE WEATHER DETAILS FOR
THURSDAY NIGHT AND FRIDAY BUT GENERALLY SHOW COOL ONSHORE FLOW
CONTINUING SOME CHANCE FOR SHOWERS. THE MODELS ARE IN FAIR AGREEMENT
ON A MORE ORGANIZED FRONTAL SYSTEM FOR THE WEEKEND...PERHAPS WITH A
WEAK TO MODEST ATMOSPHERIC RIVER. TJ

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES. HOWEVER...COASTAL TAF
SITES WILL CONTINUE TO SEE IFR FOG/STRATUS THOUGH AROUND 19Z AT
KAST AND 21Z AT KONP. PATCHY FOG IN THE SOUTH WILLAMETTE VALLEY
WILL LIKELY PERSIST THROUGH AROUND 17Z. THE FLOW TURNS ONSHORE
THIS AFTERNOON AS A WEAK FRONT APPROACHES THE REGION. THIS WILL
ALLOW MARINE STRATUS TO FILL IN AT THE COAST BETWEEN 00Z AND 03Z
TUE...WITH IFR CIGS AROUND 1000 FT. CLOUDS WILL CONTINUE TO PUSH
INLAND TONIGHT...WITH INTERIOR TAF SITES LIKELY SEEING MVFR CIGS
AROUND 1500 FT BETWEEN 12Z AND 15Z TUE AND CONTINUING THROUGH MOST
OF TUE.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AFFECTING THE TERMINAL
BY 14Z TUE.

&&

.MARINE...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WINDS WILL
SUBSIDE FURTHER TODAY AS A WEAK FRONT APPROACHES. THE FRONT WILL
MOVE ACROSS ON TUE AND SHOULD NOT CAUSE MUCH IN THE WAY OF MARINE
CONCERNS. THE NE PAC HIGH STRENGTHENS AGAIN MID-WEEK SIGNALING A
RETURN OF THE COASTAL THERMAL SURFACE LOW. THEN EXPECT A RETURN OF
THE GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS FOR TUE NIGHT AND
WED. THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT MOVES
ACROSS.

SEAS WILL REMAIN AROUND 7 FT THROUGH TUE. THE INCREASING WINDS
TUE NIGHT AND WED WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT
FOR A BRIEF PERIOD BEFORE THEY DROP BACK DOWN ON THU.  BONK.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 201603
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
858 AM PDT MON APR 20 2015

.SYNOPSIS...HIGH PRESSURE WILL CONTINUE TO PROVIDE UNSEASONABLY
WARM WEATHER TO THE PACIFIC NORTHWEST TODAY. THE RIDGE WILL SHIFT
INLAND TONIGHT AS AN UPPER TROUGH NEARS...ALLOWING A DEEPER MARINE
LAYER TO DEVELOP. THIS WILL BEGIN A SIGNIFICANT COOL DOWN FOR TUESDAY
AS LOW CLOUDS PUSH ONSHORE AHEAD OF A WEAK COLD FRONT. AN UPPER LEVEL
TROUGH WILL LINGER THROUGH THE END OF THE WEEK...KEEPING
TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL. A COOLER MORE SHOWERY
PATTERN MAY DEVELOP LATE IN THE WORK WEEK AND PERSIST THROUGH THE
WEEKEND.

&&

.SHORT TERM...VISIBLE SATELLITE IMAGERY REVEALS MAINLY CLEAR SKIES
ACROSS THE AREA EXCEPT FOR SOME FOG AND LOW STRATUS THAT HAS
DEVELOPED ALONG NEAR THE COAST OVERNIGHT UNDER NORTHERLY FLOW. A
THERMAL TROUGH CURRENTLY NEAR THE COAST WILL PUSH EAST OF THE
CASCADES LATER TODAY AND TONIGHT. THIS WILL ALLOW FOR COASTAL FOG
AND STRATUS TO PUSH INTO THE GAPS THIS EVENING AND INTO THE
WILLAMETTE VALLEY LATE TONIGHT AND TUESDAY MORNING. DUE TO LOW LEVEL
NORTHERLY FLOW...CLOUDS MAY HAVE A SOMEWHAT DIFFICULT TIME SPREADING
INTO THE ENTIRE WILLAMETTE VALLEY THOUGH.

NONETHELESS...THE INCREASE IN CLOUD COVER AND MARINE INFLUENCE AS A
WHOLE ACROSS THE REGION WILL RESULT IN MUCH COOLER HIGH TEMPERATURES
ON TUESDAY. A COLD FRONT AND ATTENDANT CLOUD COVER CURRENTLY VISIBLE
ON SATELLITE IMAGERY APPROACHING 130W WILL PUSH INTO THE PACIFIC
NORTHWEST LATE TUESDAY. AS THIS SYSTEM APPROACHES THE
REGION...ONSHORE PRESSURE GRADIENTS SHOULD INCREASE DRAMATICALLY SO
EXPECT BREEZY CONDITIONS TO DEVELOP LATE TUESDAY AFTERNOON AND
EVENING...ESPECIALLY NEAR THE COAST RANGE GAPS AND IN THE CENTRAL
COLUMBIA RIVER GORGE. THIS SHOULD ALSO RESULT IN MORE CLOUDS
SPREADING INLAND TUESDAY NIGHT AND AS A RESULT...WEDNESDAYS HIGH
TEMPERATURES SHOULD COOL EVEN FURTHER AND TOP OUT NEAR AVERAGE. HAVE
LEFT POPS IN TACT FOR TUESDAY AND WEDNESDAY...BUT ASIDE FROM A
CHANCE FOR SOME DRIZZLE...HIGHEST NEAR THE COAST...MOST LOCATIONS
LOOK TO REMAIN DRY DURING THIS PERIOD. WILL EVALUATE FURTHER WITH
THE AFTERNOON FORECAST PACKAGE. MODELS BEGIN TO DIFFER MORE
SUBSTANTIALLY ON THE STRENGTH OF A FRONTAL STORM SYSTEM AND
ATTENDANT UPPER LEVEL TROUGH ON THURSDAY SO NO CHANGES WERE MADE TO
THAT PORTION OF THE FORECAST YET. /NEUMAN


.LONG TERM...THURSDAY NIGHT THROUGH SUNDAY...PREVIOUS DISCUSSION
BELOW...MODELS ARE STRUGGLING WITH THE THE WEATHER DETAILS FOR
THURSDAY NIGHT AND FRIDAY BUT GENERALLY SHOW COOL ONSHORE FLOW
CONTINUING SOME CHANCE FOR SHOWERS. THE MODELS ARE IN FAIR AGREEMENT
ON A MORE ORGANIZED FRONTAL SYSTEM FOR THE WEEKEND...PERHAPS WITH A
WEAK TO MODEST ATMOSPHERIC RIVER. TJ

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES. HOWEVER...COASTAL TAF
SITES WILL CONTINUE TO SEE IFR FOG/STRATUS THOUGH AROUND 19Z AT
KAST AND 21Z AT KONP. PATCHY FOG IN THE SOUTH WILLAMETTE VALLEY
WILL LIKELY PERSIST THROUGH AROUND 17Z. THE FLOW TURNS ONSHORE
THIS AFTERNOON AS A WEAK FRONT APPROACHES THE REGION. THIS WILL
ALLOW MARINE STRATUS TO FILL IN AT THE COAST BETWEEN 00Z AND 03Z
TUE...WITH IFR CIGS AROUND 1000 FT. CLOUDS WILL CONTINUE TO PUSH
INLAND TONIGHT...WITH INTERIOR TAF SITES LIKELY SEEING MVFR CIGS
AROUND 1500 FT BETWEEN 12Z AND 15Z TUE AND CONTINUING THROUGH MOST
OF TUE.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AFFECTING THE TERMINAL
BY 14Z TUE.

&&

.MARINE...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WINDS WILL
SUBSIDE FURTHER TODAY AS A WEAK FRONT APPROACHES. THE FRONT WILL
MOVE ACROSS ON TUE AND SHOULD NOT CAUSE MUCH IN THE WAY OF MARINE
CONCERNS. THE NE PAC HIGH STRENGTHENS AGAIN MID-WEEK SIGNALING A
RETURN OF THE COASTAL THERMAL SURFACE LOW. THEN EXPECT A RETURN OF
THE GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS FOR TUE NIGHT AND
WED. THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT MOVES
ACROSS.

SEAS WILL REMAIN AROUND 7 FT THROUGH TUE. THE INCREASING WINDS
TUE NIGHT AND WED WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT
FOR A BRIEF PERIOD BEFORE THEY DROP BACK DOWN ON THU.  BONK.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 201603
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
858 AM PDT MON APR 20 2015

.SYNOPSIS...HIGH PRESSURE WILL CONTINUE TO PROVIDE UNSEASONABLY
WARM WEATHER TO THE PACIFIC NORTHWEST TODAY. THE RIDGE WILL SHIFT
INLAND TONIGHT AS AN UPPER TROUGH NEARS...ALLOWING A DEEPER MARINE
LAYER TO DEVELOP. THIS WILL BEGIN A SIGNIFICANT COOL DOWN FOR TUESDAY
AS LOW CLOUDS PUSH ONSHORE AHEAD OF A WEAK COLD FRONT. AN UPPER LEVEL
TROUGH WILL LINGER THROUGH THE END OF THE WEEK...KEEPING
TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL. A COOLER MORE SHOWERY
PATTERN MAY DEVELOP LATE IN THE WORK WEEK AND PERSIST THROUGH THE
WEEKEND.

&&

.SHORT TERM...VISIBLE SATELLITE IMAGERY REVEALS MAINLY CLEAR SKIES
ACROSS THE AREA EXCEPT FOR SOME FOG AND LOW STRATUS THAT HAS
DEVELOPED ALONG NEAR THE COAST OVERNIGHT UNDER NORTHERLY FLOW. A
THERMAL TROUGH CURRENTLY NEAR THE COAST WILL PUSH EAST OF THE
CASCADES LATER TODAY AND TONIGHT. THIS WILL ALLOW FOR COASTAL FOG
AND STRATUS TO PUSH INTO THE GAPS THIS EVENING AND INTO THE
WILLAMETTE VALLEY LATE TONIGHT AND TUESDAY MORNING. DUE TO LOW LEVEL
NORTHERLY FLOW...CLOUDS MAY HAVE A SOMEWHAT DIFFICULT TIME SPREADING
INTO THE ENTIRE WILLAMETTE VALLEY THOUGH.

NONETHELESS...THE INCREASE IN CLOUD COVER AND MARINE INFLUENCE AS A
WHOLE ACROSS THE REGION WILL RESULT IN MUCH COOLER HIGH TEMPERATURES
ON TUESDAY. A COLD FRONT AND ATTENDANT CLOUD COVER CURRENTLY VISIBLE
ON SATELLITE IMAGERY APPROACHING 130W WILL PUSH INTO THE PACIFIC
NORTHWEST LATE TUESDAY. AS THIS SYSTEM APPROACHES THE
REGION...ONSHORE PRESSURE GRADIENTS SHOULD INCREASE DRAMATICALLY SO
EXPECT BREEZY CONDITIONS TO DEVELOP LATE TUESDAY AFTERNOON AND
EVENING...ESPECIALLY NEAR THE COAST RANGE GAPS AND IN THE CENTRAL
COLUMBIA RIVER GORGE. THIS SHOULD ALSO RESULT IN MORE CLOUDS
SPREADING INLAND TUESDAY NIGHT AND AS A RESULT...WEDNESDAYS HIGH
TEMPERATURES SHOULD COOL EVEN FURTHER AND TOP OUT NEAR AVERAGE. HAVE
LEFT POPS IN TACT FOR TUESDAY AND WEDNESDAY...BUT ASIDE FROM A
CHANCE FOR SOME DRIZZLE...HIGHEST NEAR THE COAST...MOST LOCATIONS
LOOK TO REMAIN DRY DURING THIS PERIOD. WILL EVALUATE FURTHER WITH
THE AFTERNOON FORECAST PACKAGE. MODELS BEGIN TO DIFFER MORE
SUBSTANTIALLY ON THE STRENGTH OF A FRONTAL STORM SYSTEM AND
ATTENDANT UPPER LEVEL TROUGH ON THURSDAY SO NO CHANGES WERE MADE TO
THAT PORTION OF THE FORECAST YET. /NEUMAN


.LONG TERM...THURSDAY NIGHT THROUGH SUNDAY...PREVIOUS DISCUSSION
BELOW...MODELS ARE STRUGGLING WITH THE THE WEATHER DETAILS FOR
THURSDAY NIGHT AND FRIDAY BUT GENERALLY SHOW COOL ONSHORE FLOW
CONTINUING SOME CHANCE FOR SHOWERS. THE MODELS ARE IN FAIR AGREEMENT
ON A MORE ORGANIZED FRONTAL SYSTEM FOR THE WEEKEND...PERHAPS WITH A
WEAK TO MODEST ATMOSPHERIC RIVER. TJ

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES. HOWEVER...COASTAL TAF
SITES WILL CONTINUE TO SEE IFR FOG/STRATUS THOUGH AROUND 19Z AT
KAST AND 21Z AT KONP. PATCHY FOG IN THE SOUTH WILLAMETTE VALLEY
WILL LIKELY PERSIST THROUGH AROUND 17Z. THE FLOW TURNS ONSHORE
THIS AFTERNOON AS A WEAK FRONT APPROACHES THE REGION. THIS WILL
ALLOW MARINE STRATUS TO FILL IN AT THE COAST BETWEEN 00Z AND 03Z
TUE...WITH IFR CIGS AROUND 1000 FT. CLOUDS WILL CONTINUE TO PUSH
INLAND TONIGHT...WITH INTERIOR TAF SITES LIKELY SEEING MVFR CIGS
AROUND 1500 FT BETWEEN 12Z AND 15Z TUE AND CONTINUING THROUGH MOST
OF TUE.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AFFECTING THE TERMINAL
BY 14Z TUE.

&&

.MARINE...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WINDS WILL
SUBSIDE FURTHER TODAY AS A WEAK FRONT APPROACHES. THE FRONT WILL
MOVE ACROSS ON TUE AND SHOULD NOT CAUSE MUCH IN THE WAY OF MARINE
CONCERNS. THE NE PAC HIGH STRENGTHENS AGAIN MID-WEEK SIGNALING A
RETURN OF THE COASTAL THERMAL SURFACE LOW. THEN EXPECT A RETURN OF
THE GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS FOR TUE NIGHT AND
WED. THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT MOVES
ACROSS.

SEAS WILL REMAIN AROUND 7 FT THROUGH TUE. THE INCREASING WINDS
TUE NIGHT AND WED WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT
FOR A BRIEF PERIOD BEFORE THEY DROP BACK DOWN ON THU.  BONK.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 201603
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
858 AM PDT MON APR 20 2015

.SYNOPSIS...HIGH PRESSURE WILL CONTINUE TO PROVIDE UNSEASONABLY
WARM WEATHER TO THE PACIFIC NORTHWEST TODAY. THE RIDGE WILL SHIFT
INLAND TONIGHT AS AN UPPER TROUGH NEARS...ALLOWING A DEEPER MARINE
LAYER TO DEVELOP. THIS WILL BEGIN A SIGNIFICANT COOL DOWN FOR TUESDAY
AS LOW CLOUDS PUSH ONSHORE AHEAD OF A WEAK COLD FRONT. AN UPPER LEVEL
TROUGH WILL LINGER THROUGH THE END OF THE WEEK...KEEPING
TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL. A COOLER MORE SHOWERY
PATTERN MAY DEVELOP LATE IN THE WORK WEEK AND PERSIST THROUGH THE
WEEKEND.

&&

.SHORT TERM...VISIBLE SATELLITE IMAGERY REVEALS MAINLY CLEAR SKIES
ACROSS THE AREA EXCEPT FOR SOME FOG AND LOW STRATUS THAT HAS
DEVELOPED ALONG NEAR THE COAST OVERNIGHT UNDER NORTHERLY FLOW. A
THERMAL TROUGH CURRENTLY NEAR THE COAST WILL PUSH EAST OF THE
CASCADES LATER TODAY AND TONIGHT. THIS WILL ALLOW FOR COASTAL FOG
AND STRATUS TO PUSH INTO THE GAPS THIS EVENING AND INTO THE
WILLAMETTE VALLEY LATE TONIGHT AND TUESDAY MORNING. DUE TO LOW LEVEL
NORTHERLY FLOW...CLOUDS MAY HAVE A SOMEWHAT DIFFICULT TIME SPREADING
INTO THE ENTIRE WILLAMETTE VALLEY THOUGH.

NONETHELESS...THE INCREASE IN CLOUD COVER AND MARINE INFLUENCE AS A
WHOLE ACROSS THE REGION WILL RESULT IN MUCH COOLER HIGH TEMPERATURES
ON TUESDAY. A COLD FRONT AND ATTENDANT CLOUD COVER CURRENTLY VISIBLE
ON SATELLITE IMAGERY APPROACHING 130W WILL PUSH INTO THE PACIFIC
NORTHWEST LATE TUESDAY. AS THIS SYSTEM APPROACHES THE
REGION...ONSHORE PRESSURE GRADIENTS SHOULD INCREASE DRAMATICALLY SO
EXPECT BREEZY CONDITIONS TO DEVELOP LATE TUESDAY AFTERNOON AND
EVENING...ESPECIALLY NEAR THE COAST RANGE GAPS AND IN THE CENTRAL
COLUMBIA RIVER GORGE. THIS SHOULD ALSO RESULT IN MORE CLOUDS
SPREADING INLAND TUESDAY NIGHT AND AS A RESULT...WEDNESDAYS HIGH
TEMPERATURES SHOULD COOL EVEN FURTHER AND TOP OUT NEAR AVERAGE. HAVE
LEFT POPS IN TACT FOR TUESDAY AND WEDNESDAY...BUT ASIDE FROM A
CHANCE FOR SOME DRIZZLE...HIGHEST NEAR THE COAST...MOST LOCATIONS
LOOK TO REMAIN DRY DURING THIS PERIOD. WILL EVALUATE FURTHER WITH
THE AFTERNOON FORECAST PACKAGE. MODELS BEGIN TO DIFFER MORE
SUBSTANTIALLY ON THE STRENGTH OF A FRONTAL STORM SYSTEM AND
ATTENDANT UPPER LEVEL TROUGH ON THURSDAY SO NO CHANGES WERE MADE TO
THAT PORTION OF THE FORECAST YET. /NEUMAN


.LONG TERM...THURSDAY NIGHT THROUGH SUNDAY...PREVIOUS DISCUSSION
BELOW...MODELS ARE STRUGGLING WITH THE THE WEATHER DETAILS FOR
THURSDAY NIGHT AND FRIDAY BUT GENERALLY SHOW COOL ONSHORE FLOW
CONTINUING SOME CHANCE FOR SHOWERS. THE MODELS ARE IN FAIR AGREEMENT
ON A MORE ORGANIZED FRONTAL SYSTEM FOR THE WEEKEND...PERHAPS WITH A
WEAK TO MODEST ATMOSPHERIC RIVER. TJ

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES. HOWEVER...COASTAL TAF
SITES WILL CONTINUE TO SEE IFR FOG/STRATUS THOUGH AROUND 19Z AT
KAST AND 21Z AT KONP. PATCHY FOG IN THE SOUTH WILLAMETTE VALLEY
WILL LIKELY PERSIST THROUGH AROUND 17Z. THE FLOW TURNS ONSHORE
THIS AFTERNOON AS A WEAK FRONT APPROACHES THE REGION. THIS WILL
ALLOW MARINE STRATUS TO FILL IN AT THE COAST BETWEEN 00Z AND 03Z
TUE...WITH IFR CIGS AROUND 1000 FT. CLOUDS WILL CONTINUE TO PUSH
INLAND TONIGHT...WITH INTERIOR TAF SITES LIKELY SEEING MVFR CIGS
AROUND 1500 FT BETWEEN 12Z AND 15Z TUE AND CONTINUING THROUGH MOST
OF TUE.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AFFECTING THE TERMINAL
BY 14Z TUE.

&&

.MARINE...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WINDS WILL
SUBSIDE FURTHER TODAY AS A WEAK FRONT APPROACHES. THE FRONT WILL
MOVE ACROSS ON TUE AND SHOULD NOT CAUSE MUCH IN THE WAY OF MARINE
CONCERNS. THE NE PAC HIGH STRENGTHENS AGAIN MID-WEEK SIGNALING A
RETURN OF THE COASTAL THERMAL SURFACE LOW. THEN EXPECT A RETURN OF
THE GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS FOR TUE NIGHT AND
WED. THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT MOVES
ACROSS.

SEAS WILL REMAIN AROUND 7 FT THROUGH TUE. THE INCREASING WINDS
TUE NIGHT AND WED WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT
FOR A BRIEF PERIOD BEFORE THEY DROP BACK DOWN ON THU.  BONK.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 201603
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
858 AM PDT MON APR 20 2015

.SYNOPSIS...HIGH PRESSURE WILL CONTINUE TO PROVIDE UNSEASONABLY
WARM WEATHER TO THE PACIFIC NORTHWEST TODAY. THE RIDGE WILL SHIFT
INLAND TONIGHT AS AN UPPER TROUGH NEARS...ALLOWING A DEEPER MARINE
LAYER TO DEVELOP. THIS WILL BEGIN A SIGNIFICANT COOL DOWN FOR TUESDAY
AS LOW CLOUDS PUSH ONSHORE AHEAD OF A WEAK COLD FRONT. AN UPPER LEVEL
TROUGH WILL LINGER THROUGH THE END OF THE WEEK...KEEPING
TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL. A COOLER MORE SHOWERY
PATTERN MAY DEVELOP LATE IN THE WORK WEEK AND PERSIST THROUGH THE
WEEKEND.

&&

.SHORT TERM...VISIBLE SATELLITE IMAGERY REVEALS MAINLY CLEAR SKIES
ACROSS THE AREA EXCEPT FOR SOME FOG AND LOW STRATUS THAT HAS
DEVELOPED ALONG NEAR THE COAST OVERNIGHT UNDER NORTHERLY FLOW. A
THERMAL TROUGH CURRENTLY NEAR THE COAST WILL PUSH EAST OF THE
CASCADES LATER TODAY AND TONIGHT. THIS WILL ALLOW FOR COASTAL FOG
AND STRATUS TO PUSH INTO THE GAPS THIS EVENING AND INTO THE
WILLAMETTE VALLEY LATE TONIGHT AND TUESDAY MORNING. DUE TO LOW LEVEL
NORTHERLY FLOW...CLOUDS MAY HAVE A SOMEWHAT DIFFICULT TIME SPREADING
INTO THE ENTIRE WILLAMETTE VALLEY THOUGH.

NONETHELESS...THE INCREASE IN CLOUD COVER AND MARINE INFLUENCE AS A
WHOLE ACROSS THE REGION WILL RESULT IN MUCH COOLER HIGH TEMPERATURES
ON TUESDAY. A COLD FRONT AND ATTENDANT CLOUD COVER CURRENTLY VISIBLE
ON SATELLITE IMAGERY APPROACHING 130W WILL PUSH INTO THE PACIFIC
NORTHWEST LATE TUESDAY. AS THIS SYSTEM APPROACHES THE
REGION...ONSHORE PRESSURE GRADIENTS SHOULD INCREASE DRAMATICALLY SO
EXPECT BREEZY CONDITIONS TO DEVELOP LATE TUESDAY AFTERNOON AND
EVENING...ESPECIALLY NEAR THE COAST RANGE GAPS AND IN THE CENTRAL
COLUMBIA RIVER GORGE. THIS SHOULD ALSO RESULT IN MORE CLOUDS
SPREADING INLAND TUESDAY NIGHT AND AS A RESULT...WEDNESDAYS HIGH
TEMPERATURES SHOULD COOL EVEN FURTHER AND TOP OUT NEAR AVERAGE. HAVE
LEFT POPS IN TACT FOR TUESDAY AND WEDNESDAY...BUT ASIDE FROM A
CHANCE FOR SOME DRIZZLE...HIGHEST NEAR THE COAST...MOST LOCATIONS
LOOK TO REMAIN DRY DURING THIS PERIOD. WILL EVALUATE FURTHER WITH
THE AFTERNOON FORECAST PACKAGE. MODELS BEGIN TO DIFFER MORE
SUBSTANTIALLY ON THE STRENGTH OF A FRONTAL STORM SYSTEM AND
ATTENDANT UPPER LEVEL TROUGH ON THURSDAY SO NO CHANGES WERE MADE TO
THAT PORTION OF THE FORECAST YET. /NEUMAN


.LONG TERM...THURSDAY NIGHT THROUGH SUNDAY...PREVIOUS DISCUSSION
BELOW...MODELS ARE STRUGGLING WITH THE THE WEATHER DETAILS FOR
THURSDAY NIGHT AND FRIDAY BUT GENERALLY SHOW COOL ONSHORE FLOW
CONTINUING SOME CHANCE FOR SHOWERS. THE MODELS ARE IN FAIR AGREEMENT
ON A MORE ORGANIZED FRONTAL SYSTEM FOR THE WEEKEND...PERHAPS WITH A
WEAK TO MODEST ATMOSPHERIC RIVER. TJ

&&

.AVIATION...MOSTLY VFR UNDER HAZY SKIES. HOWEVER...COASTAL TAF
SITES WILL CONTINUE TO SEE IFR FOG/STRATUS THOUGH AROUND 19Z AT
KAST AND 21Z AT KONP. PATCHY FOG IN THE SOUTH WILLAMETTE VALLEY
WILL LIKELY PERSIST THROUGH AROUND 17Z. THE FLOW TURNS ONSHORE
THIS AFTERNOON AS A WEAK FRONT APPROACHES THE REGION. THIS WILL
ALLOW MARINE STRATUS TO FILL IN AT THE COAST BETWEEN 00Z AND 03Z
TUE...WITH IFR CIGS AROUND 1000 FT. CLOUDS WILL CONTINUE TO PUSH
INLAND TONIGHT...WITH INTERIOR TAF SITES LIKELY SEEING MVFR CIGS
AROUND 1500 FT BETWEEN 12Z AND 15Z TUE AND CONTINUING THROUGH MOST
OF TUE.

KPDX AND APPROACHES...VFR UNDER HAZY SKIES THROUGH THIS EVENING.
CLOUDS RETURN TONIGHT...WITH MVFR STRATUS AFFECTING THE TERMINAL
BY 14Z TUE.

&&

.MARINE...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WINDS WILL
SUBSIDE FURTHER TODAY AS A WEAK FRONT APPROACHES. THE FRONT WILL
MOVE ACROSS ON TUE AND SHOULD NOT CAUSE MUCH IN THE WAY OF MARINE
CONCERNS. THE NE PAC HIGH STRENGTHENS AGAIN MID-WEEK SIGNALING A
RETURN OF THE COASTAL THERMAL SURFACE LOW. THEN EXPECT A RETURN OF
THE GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS FOR TUE NIGHT AND
WED. THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT MOVES
ACROSS.

SEAS WILL REMAIN AROUND 7 FT THROUGH TUE. THE INCREASING WINDS
TUE NIGHT AND WED WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT
FOR A BRIEF PERIOD BEFORE THEY DROP BACK DOWN ON THU.  BONK.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KOTX 201110
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
410 AM PDT MON APR 20 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and much cooler temperatures. After this, a number of potential
waves track across the Inland Northwest. The heaviest amounts of
precipitation will fall across North Idaho, with snow levels high
enough to not pose a heavy accumulation threat to any regional
passes. However, given the showery and possibly thundery nature
to the weather pattern, snow showers could fall to well below pass
level in the heaviest showers. Expect very wide ranges in
precipitation amounts over short distances. The only certainty is
that the mountain zones of northeast Washington and the Idaho
Panhandle will be the wettest.

&&

.DISCUSSION...
Today through Tuesday: Mild, mostly dry weather is expected
across the Inland NW, though a cold front approaching the coast
will bring changes to our doorstep. First this morning WV/IR
satellite shows the ridge axis edging onto the Pacific Coast.
Models are in good agreement in continuing to shift that ridge
toward the WA/ID border over the next 24-hours. During that time
the region remains in a northwesterly flow, with occasional high
clouds shifting into Montana. A weak disturbance in that flow may
bring a few more clouds near the Cascades and northern mountains
in the afternoon and evening. Some guidance even shows a small
shower threat in the northern Cascades, around Okanogan county.
However the atmosphere seems too dry and instability isn`t
impressive, so this threat will be very limited. As for
temperatures, models show regional 850 mb temperatures warm about
1-2 degrees over Sunday under the shifting ridge. So today`s highs
should be 2 to 4 degrees warmer. However, for most, Tuesday looks
like the warmest day. Through Tuesday the mid-level ridge shifts
toward western Montana, a mid-level trough and its leading cold
front approach the coast and the flow turns southwesterly with
WAA. So highs look to be another 2 to 4 degrees milder than today,
meaning mid 70s to lower 80s (or about 10 to 15 degrees above
normal). The exception will be near the Cascades with the
increasing onshore flow, leaving that area slightly cooler as
compared to Monday. The incoming cold front will also bring some
clouds and a chance of rain to the Cascade crest Tuesday
afternoon, maybe a stray clap or thunder. Otherwise the region
looks dry and mostly clear. /J. Cote`

Tues Nt through Mon: With similar timing between the
GFS/ECMWF/NAM that the frontal and upper trof passage will take
place Tues Nt through Wed Nt, we tried to fine tune the temporal
specifics a bit but, more importantly, lowered snow levels and
cooled temperatures. The degree of cooling, areal coverage of
thunder potential, and snow/graupel chances will be highly
dependent upon the strength of the upper trough. In the latest
model runs, the GFS is much deeper (and slower) with the upper
low Wed evening over the Idaho Panhandle, which is the outlier.
Therefore, we did not increase pcpn amnts significantly for the NE
Wa and N Idaho Panhandle zones. The thunder threat still looks
likely Wed though, based on soundings, the threat may be more for
graupel than a meaningful thunder event. The second wave moving
into the region for Fri shows the ECMWF as the cooler and much
deeper wave (compared to the GFS), but both similar in character
as far as sensible weather as the Wed wave. Given these continued
uncertainties, which has been the case for the last five to ten
model runs, we simply trended cooler with more showers and
slightly lower snow levels. bz


&&

.AVIATION...
12Z TAFS: Mid-level high pressure will continue to migrate inland
through Tuesday morning. Expect some middle to high clouds, but
otherwise dry and VFR conditions with light and diurnally and
terrain driven winds. /J. Cote`

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        72  46  75  50  65  41 /   0   0  10  10  20  30
Coeur d`Alene  70  41  75  44  65  41 /   0   0  10  10  30  30
Pullman        69  42  74  46  64  39 /   0   0  10  10  20  20
Lewiston       76  46  78  49  70  43 /   0   0   0  10  20  20
Colville       75  42  77  46  68  43 /   0   0  10  10  40  30
Sandpoint      69  38  73  40  67  39 /   0   0  10  10  40  40
Kellogg        68  40  74  43  67  39 /   0   0  10  10  40  30
Moses Lake     77  44  78  50  67  41 /   0   0  10  10  20  10
Wenatchee      77  51  77  53  66  43 /   0   0  10  10  20  10
Omak           77  44  77  47  66  40 /   0   0  10  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KSEW 200955
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
300 AM PDT MON APR 20 2015

.SYNOPSIS...A RIDGE OF HIGH PRESSURE ALOFT WILL GIVE DRY AND WARM
WEATHER TO THE AREA TODAY. THE RIDGE WILL SHIFT INLAND TONIGHT
ALLOWING MARINE AIR TO PUSH INLAND. A FRONTAL SYSTEM AND COLD UPPER
TROUGH WILL MOVE EAST ACROSS THE AREA TUESDAY AFTERNOON THROUGH
WEDNESDAY BRINGING SHOWERS...BREEZY TO WINDY CONDITIONS...AND MUCH
COOLER WEATHER. ANOTHER FRONT WILL MOVE THROUGH THE REGION ON
THURSDAY. A STRONG FRONT WILL GIVE WET AND BREEZY CONDITIONS TO THE
REGION NEXT WEEKEND.

&&

.SHORT TERM...ANOTHER VERY NICE SPRING DAY IS IN STORE TODAY AS AN
UPPER LEVEL RIDGE MOVES EAST ACROSS THE AREA. WHILE TEMPERATURES
ALOFT WILL BE SIMILAR THIS AFTERNOON AS WHAT WE SAW ON SUNDAY...
LIGHTER LOW LEVEL NORTHERLY FLOW DURING THE EARLY TO MID AFTERNOON
HOURS SHOULD ALLOW HIGH TEMPERATURES IN THE INTERIOR TO RISE A
DEGREE OR TWO ABOVE SUNDAYS VALUES.

A TRANSITION TO A CLOUDY...COOL...AND SOMEWHAT WET PATTERN STARTS
TONIGHT AND RAMPS UP DURING THE DAY ON TUESDAY. MODELS CONTINUE TO
HAVE TIMING ISSUES WITH REGARD TO THE DEVELOPMENT OF A STRONG PUSH
OF MARINE AIR INLAND. FOR TONIGHT...MODELS DEVELOP A MODERATE PUSH
THROUGH THE STRAIT OF JUAN DE FUCA AND THE CHEHALIS GAP. THE PUSH
APPEARS TO BE UNDERSTATED BY THE MODELS AS THERMAL GRADIENTS BETWEEN
THE COAST AND THE INTERIOR AROUND 00Z THIS AFTERNOON WILL BE RATHER
STRONG. I WOULD NOT BE SURPRISED IF THE ONSHORE FLOW TONIGHT IS
STRONGER THAN MODELS SHOW AND CLOUDS SPREAD FARTHER INLAND BY EARLY
TUESDAY THAN CURRENTLY FORECAST. BUT WILL LET THE NEXT SHIFT FINE
TUNE THE TIMING AFTER LOOKING AT THE 12Z GUIDANCE.

IN THE MEANTIME...STRATUS AND FOG WILL LIKELY BE PUSHING ONTO THE
COAST BY SUNSET. THE FOG AND STRATUS IN THE NWLY FLOW CAN ALREADY BE
SEEN OVER THE OFFSHORE WATERS ON THE MULTISPECTRAL SATELLITE
IMAGERY...AND IT IS MAKING PRETTY GOOD EASTWARD PROGRESS. THE
VARIOUS MODELS HAVE ONSHORE PRES GRADIENTS RAMPING UP TUESDAY
AFTERNOON AS A COLD FRONT...THE ONE NOW SEEN NEAR 134W...SWEEPS
ACROSS THE AREA. THE KUIL-KBLI GRADIENT RISES TO OVER 5 MB BY 00Z
WED IN THE GFS AND IS SIMILARLY STRONG IN THE OTHER MODELS. GOOD
HEIGHT AND TEMPERATURE FALLS ALOFT COMBINED WITH STRONG ONSHORE FLOW
AND CONVERGENCE AROUND THE TERRAIN TUESDAY AFTERNOON THROUGH
WEDNESDAY MORNING PROMPTED THE INCREASE IN POPS FOR TUESDAY
AFTERNOON THROUGH EARLY WEDNESDAY.

SNOW LEVELS WILL QUICKLY CRASH BEHIND THE FRONT FROM THE WEST
TUESDAY NIGHT INTO EARLY WEDNESDAY...DOWN TO AROUND 3500 FEET. QPF
WITH THE FAST MOVING TROUGH...ONSHORE FLOW...AND CONVERGENCE ZONE
APPEARS LOW ENOUGH HOWEVER THAT ONLY A COUPLE OF INCHES OF SNOW MAY
BE SEEN ON THE PASSES.

SHOWER CHANCES DECREASE FROM THE WEST LATER WEDNESDAY INTO WEDNESDAY
NIGHT AS A SHORT WAVE RIDGE MOVES ACROSS THE AREA. IT WILL STAY
MOSTLY CLOUDY AND COOL THOUGH WITH LOW LEVEL ONSHORE FLOW.

ANOTHER FRONT AND UPPER LEVEL TROUGH WILL GIVE AN INCREASE IN POPS
FROM THE WEST DURING THE DAY THURSDAY AS IT APPROACHES. ALBRECHT

.LONG TERM...A FRONT AND UPPER TROUGH MOVES ACROSS THE AREA LATE
THURSDAY INTO FRIDAY AND IS FOLLOWED BY A WETTER AND STRONGER FRONT
NEXT WEEKEND. TEMPERATURES WILL AVERAGE ABOUT 5 DEGREES BELOW NORMAL
THU NIGHT THROUGH EARLY NEXT WEEK...AND THE WEEKEND FRONT COULD DROP
AN INCH OR SO OF RAIN IN THE LOWLANDS AND 2-4 INCHES OF RAIN IN THE
MOUNTAINS. ALBRECHT

&&

.AVIATION...AN UPPER LEVEL RIDGE OVER THE PAC NW WILL LEAD TO DRY
AND STABLE WEATHER ACROSS WESTERN WA TODAY. THE FLOW ALOFT IS
WESTERLY. VFR CONDITIONS ARE EXPECTED. SKIES WILL REMAIN MOSTLY
CLEAR WITH JUST FEW-SCT CIRRUS ALOFT. A MARINE PUSH WILL BRING LOW
CLOUDS TO THE COAST THIS EVENING WITH STRATUS MOVING INTO THE
INTERIOR EARLY TUE...MVFR TO IFR CIGS ARE LIKELY. 33

KSEA...VFR CONDITIONS TODAY. EXPECT N WINDS TO 10 KT. LOW LEVEL
MARINE CLOUDS WILL PUSH INLAND LATE TONIGHT OR EARLY TUE MORNING
WITH MVFR TO IFR CIGS LIKELY. 33

&&

.MARINE...LOW PRES /THERMAL TROUGH/ OVER WESTERN WA WILL SHIFT
INLAND AND EAST OF THE CASCADES TODAY WITH ONSHORE FLOW DEVELOPING.
MODELS SHOW SMALL CRAFT ADVISORY WEST WINDS THROUGH THE STRAIT OF
JUAN DE FUCA WITH THIS ONSHORE PUSH LATE THIS AFTERNOON AND EVENING.
ONSHORE FLOW WILL INCREASE FURTHER ON TUESDAY AS A COLD FRONT MOVES
THROUGH THE AREA. GALES ARE POSSIBLE OVER THE COASTAL WATERS AND
THROUGH THE STRAIT. ONSHORE FLOW WILL CONTINUE THROUGH WEDNESDAY
ALTHOUGH WINDS WILL EASE. ANOTHER COLD FRONT WILL ARRIVE LATE
WEDNESDAY NIGHT OR THURSDAY. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY CENTRAL AND EAST STRAIT OF JUAN DE FUCA
      STARTING 5 PM THIS AFTERNOON.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML






000
FXUS66 KOTX 200943
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 AM PDT MON APR 20 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and much cooler temperatures. After this, a number of potential
waves track across the Inland Northwest. The heaviest amounts of
precipitation will fall across North Idaho, with snow levels high
enough to not pose a heavy accumulation threat to any regional
passes. However, given the showery and possibly thundery nature
to the weather pattern, snow showers could fall to well below pass
level in the heaviest showers. Expect very wide ranges in
precipitation amounts over short distances. The only certainty is
that the mountain zones of northeast Washington and the Idaho
Panhandle will be the wettest.

&&

.DISCUSSION...
Today through Tuesday: Mild, mostly dry weather is expected
across the Inland NW, though a cold front approaching the coast
will bring changes to our doorstep. First this morning WV/IR
satellite shows the ridge axis edging onto the Pacific Coast.
Models are in good agreement in continuing to shift that ridge
toward the WA/ID border over the next 24-hours. During that time
the region remains in a northwesterly flow, with occasional high
clouds shifting into Montana. A weak disturbance in that flow may
bring a few more clouds near the Cascades and northern mountains
in the afternoon and evening. Some guidance even shows a small
shower threat in the northern Cascades, around Okanogan county.
However the atmosphere seems too dry and instability isn`t
impressive, so this threat will be very limited. As for
temperatures, models show regional 850 mb temperatures warm about
1-2 degrees over Sunday under the shifting ridge. So today`s highs
should be 2 to 4 degrees warmer. However, for most, Tuesday looks
like the warmest day. Through Tuesday the mid-level ridge shifts
toward western Montana, a mid-level trough and its leading cold
front approach the coast and the flow turns southwesterly with
WAA. So highs look to be another 2 to 4 degrees milder than today,
meaning mid 70s to lower 80s (or about 10 to 15 degrees above
normal). The exception will be near the Cascades with the
increasing onshore flow, leaving that area slightly cooler as
compared to Monday. The incoming cold front will also bring some
clouds and a chance of rain to the Cascade crest Tuesday
afternoon, maybe a stray clap or thunder. Otherwise the region
looks dry and mostly clear. /J. Cote`

Tues Nt through Mon: With similar timing between the
GFS/ECMWF/NAM that the frontal and upper trof passage will take
place Tues Nt through Wed Nt, we tried to fine tune the temporal
specifics a bit but, more importantly, lowered snow levels and
cooled temperatures. The degree of cooling, areal coverage of
thunder potential, and snow/graupel chances will be highly
dependent upon the strength of the upper trough. In the latest
model runs, the GFS is much deeper (and slower) with the upper
low Wed evening over the Idaho Panhandle, which is the outlier.
Therefore, we did not increase pcpn amnts significantly for the NE
Wa and N Idaho Panhandle zones. The thunder threat still looks
likely Wed though, based on soundings, the threat may be more for
graupel than a meaningful thunder event. The second wave moving
into the region for Fri shows the ECMWF as the cooler and much
deeper wave (compared to the GFS), but both similar in character
as far as sensible weather as the Wed wave. Given these continued
uncertainties, which has been the case for the last five to ten
model runs, we simply trended cooler with more showers and
slightly lower snow levels. bz


&&

.AVIATION...
06Z TAFS: High pressure building into the region will result in
VFR conditions through 06Z Tuesday. Winds will remain weak and
some passing high cirrus can be expected to drop south into the
region out of BC. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        72  46  75  50  65  41 /   0   0  10  10  20  30
Coeur d`Alene  70  41  75  44  65  41 /   0   0  10  10  30  30
Pullman        69  42  74  46  64  39 /   0   0  10  10  20  20
Lewiston       76  46  78  49  70  43 /   0   0   0  10  20  20
Colville       75  42  77  46  68  43 /   0   0  10  10  40  30
Sandpoint      69  38  73  40  67  39 /   0   0  10  10  40  40
Kellogg        68  40  74  43  67  39 /   0   0  10  10  40  30
Moses Lake     77  44  78  50  67  41 /   0   0  10  10  20  10
Wenatchee      77  51  77  53  66  43 /   0   0  10  10  20  10
Omak           77  44  77  47  66  40 /   0   0  10  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 200943
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 AM PDT MON APR 20 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and much cooler temperatures. After this, a number of potential
waves track across the Inland Northwest. The heaviest amounts of
precipitation will fall across North Idaho, with snow levels high
enough to not pose a heavy accumulation threat to any regional
passes. However, given the showery and possibly thundery nature
to the weather pattern, snow showers could fall to well below pass
level in the heaviest showers. Expect very wide ranges in
precipitation amounts over short distances. The only certainty is
that the mountain zones of northeast Washington and the Idaho
Panhandle will be the wettest.

&&

.DISCUSSION...
Today through Tuesday: Mild, mostly dry weather is expected
across the Inland NW, though a cold front approaching the coast
will bring changes to our doorstep. First this morning WV/IR
satellite shows the ridge axis edging onto the Pacific Coast.
Models are in good agreement in continuing to shift that ridge
toward the WA/ID border over the next 24-hours. During that time
the region remains in a northwesterly flow, with occasional high
clouds shifting into Montana. A weak disturbance in that flow may
bring a few more clouds near the Cascades and northern mountains
in the afternoon and evening. Some guidance even shows a small
shower threat in the northern Cascades, around Okanogan county.
However the atmosphere seems too dry and instability isn`t
impressive, so this threat will be very limited. As for
temperatures, models show regional 850 mb temperatures warm about
1-2 degrees over Sunday under the shifting ridge. So today`s highs
should be 2 to 4 degrees warmer. However, for most, Tuesday looks
like the warmest day. Through Tuesday the mid-level ridge shifts
toward western Montana, a mid-level trough and its leading cold
front approach the coast and the flow turns southwesterly with
WAA. So highs look to be another 2 to 4 degrees milder than today,
meaning mid 70s to lower 80s (or about 10 to 15 degrees above
normal). The exception will be near the Cascades with the
increasing onshore flow, leaving that area slightly cooler as
compared to Monday. The incoming cold front will also bring some
clouds and a chance of rain to the Cascade crest Tuesday
afternoon, maybe a stray clap or thunder. Otherwise the region
looks dry and mostly clear. /J. Cote`

Tues Nt through Mon: With similar timing between the
GFS/ECMWF/NAM that the frontal and upper trof passage will take
place Tues Nt through Wed Nt, we tried to fine tune the temporal
specifics a bit but, more importantly, lowered snow levels and
cooled temperatures. The degree of cooling, areal coverage of
thunder potential, and snow/graupel chances will be highly
dependent upon the strength of the upper trough. In the latest
model runs, the GFS is much deeper (and slower) with the upper
low Wed evening over the Idaho Panhandle, which is the outlier.
Therefore, we did not increase pcpn amnts significantly for the NE
Wa and N Idaho Panhandle zones. The thunder threat still looks
likely Wed though, based on soundings, the threat may be more for
graupel than a meaningful thunder event. The second wave moving
into the region for Fri shows the ECMWF as the cooler and much
deeper wave (compared to the GFS), but both similar in character
as far as sensible weather as the Wed wave. Given these continued
uncertainties, which has been the case for the last five to ten
model runs, we simply trended cooler with more showers and
slightly lower snow levels. bz


&&

.AVIATION...
06Z TAFS: High pressure building into the region will result in
VFR conditions through 06Z Tuesday. Winds will remain weak and
some passing high cirrus can be expected to drop south into the
region out of BC. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        72  46  75  50  65  41 /   0   0  10  10  20  30
Coeur d`Alene  70  41  75  44  65  41 /   0   0  10  10  30  30
Pullman        69  42  74  46  64  39 /   0   0  10  10  20  20
Lewiston       76  46  78  49  70  43 /   0   0   0  10  20  20
Colville       75  42  77  46  68  43 /   0   0  10  10  40  30
Sandpoint      69  38  73  40  67  39 /   0   0  10  10  40  40
Kellogg        68  40  74  43  67  39 /   0   0  10  10  40  30
Moses Lake     77  44  78  50  67  41 /   0   0  10  10  20  10
Wenatchee      77  51  77  53  66  43 /   0   0  10  10  20  10
Omak           77  44  77  47  66  40 /   0   0  10  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 200943
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 AM PDT MON APR 20 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and much cooler temperatures. After this, a number of potential
waves track across the Inland Northwest. The heaviest amounts of
precipitation will fall across North Idaho, with snow levels high
enough to not pose a heavy accumulation threat to any regional
passes. However, given the showery and possibly thundery nature
to the weather pattern, snow showers could fall to well below pass
level in the heaviest showers. Expect very wide ranges in
precipitation amounts over short distances. The only certainty is
that the mountain zones of northeast Washington and the Idaho
Panhandle will be the wettest.

&&

.DISCUSSION...
Today through Tuesday: Mild, mostly dry weather is expected
across the Inland NW, though a cold front approaching the coast
will bring changes to our doorstep. First this morning WV/IR
satellite shows the ridge axis edging onto the Pacific Coast.
Models are in good agreement in continuing to shift that ridge
toward the WA/ID border over the next 24-hours. During that time
the region remains in a northwesterly flow, with occasional high
clouds shifting into Montana. A weak disturbance in that flow may
bring a few more clouds near the Cascades and northern mountains
in the afternoon and evening. Some guidance even shows a small
shower threat in the northern Cascades, around Okanogan county.
However the atmosphere seems too dry and instability isn`t
impressive, so this threat will be very limited. As for
temperatures, models show regional 850 mb temperatures warm about
1-2 degrees over Sunday under the shifting ridge. So today`s highs
should be 2 to 4 degrees warmer. However, for most, Tuesday looks
like the warmest day. Through Tuesday the mid-level ridge shifts
toward western Montana, a mid-level trough and its leading cold
front approach the coast and the flow turns southwesterly with
WAA. So highs look to be another 2 to 4 degrees milder than today,
meaning mid 70s to lower 80s (or about 10 to 15 degrees above
normal). The exception will be near the Cascades with the
increasing onshore flow, leaving that area slightly cooler as
compared to Monday. The incoming cold front will also bring some
clouds and a chance of rain to the Cascade crest Tuesday
afternoon, maybe a stray clap or thunder. Otherwise the region
looks dry and mostly clear. /J. Cote`

Tues Nt through Mon: With similar timing between the
GFS/ECMWF/NAM that the frontal and upper trof passage will take
place Tues Nt through Wed Nt, we tried to fine tune the temporal
specifics a bit but, more importantly, lowered snow levels and
cooled temperatures. The degree of cooling, areal coverage of
thunder potential, and snow/graupel chances will be highly
dependent upon the strength of the upper trough. In the latest
model runs, the GFS is much deeper (and slower) with the upper
low Wed evening over the Idaho Panhandle, which is the outlier.
Therefore, we did not increase pcpn amnts significantly for the NE
Wa and N Idaho Panhandle zones. The thunder threat still looks
likely Wed though, based on soundings, the threat may be more for
graupel than a meaningful thunder event. The second wave moving
into the region for Fri shows the ECMWF as the cooler and much
deeper wave (compared to the GFS), but both similar in character
as far as sensible weather as the Wed wave. Given these continued
uncertainties, which has been the case for the last five to ten
model runs, we simply trended cooler with more showers and
slightly lower snow levels. bz


&&

.AVIATION...
06Z TAFS: High pressure building into the region will result in
VFR conditions through 06Z Tuesday. Winds will remain weak and
some passing high cirrus can be expected to drop south into the
region out of BC. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        72  46  75  50  65  41 /   0   0  10  10  20  30
Coeur d`Alene  70  41  75  44  65  41 /   0   0  10  10  30  30
Pullman        69  42  74  46  64  39 /   0   0  10  10  20  20
Lewiston       76  46  78  49  70  43 /   0   0   0  10  20  20
Colville       75  42  77  46  68  43 /   0   0  10  10  40  30
Sandpoint      69  38  73  40  67  39 /   0   0  10  10  40  40
Kellogg        68  40  74  43  67  39 /   0   0  10  10  40  30
Moses Lake     77  44  78  50  67  41 /   0   0  10  10  20  10
Wenatchee      77  51  77  53  66  43 /   0   0  10  10  20  10
Omak           77  44  77  47  66  40 /   0   0  10  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KOTX 200943
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
243 AM PDT MON APR 20 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and much cooler temperatures. After this, a number of potential
waves track across the Inland Northwest. The heaviest amounts of
precipitation will fall across North Idaho, with snow levels high
enough to not pose a heavy accumulation threat to any regional
passes. However, given the showery and possibly thundery nature
to the weather pattern, snow showers could fall to well below pass
level in the heaviest showers. Expect very wide ranges in
precipitation amounts over short distances. The only certainty is
that the mountain zones of northeast Washington and the Idaho
Panhandle will be the wettest.

&&

.DISCUSSION...
Today through Tuesday: Mild, mostly dry weather is expected
across the Inland NW, though a cold front approaching the coast
will bring changes to our doorstep. First this morning WV/IR
satellite shows the ridge axis edging onto the Pacific Coast.
Models are in good agreement in continuing to shift that ridge
toward the WA/ID border over the next 24-hours. During that time
the region remains in a northwesterly flow, with occasional high
clouds shifting into Montana. A weak disturbance in that flow may
bring a few more clouds near the Cascades and northern mountains
in the afternoon and evening. Some guidance even shows a small
shower threat in the northern Cascades, around Okanogan county.
However the atmosphere seems too dry and instability isn`t
impressive, so this threat will be very limited. As for
temperatures, models show regional 850 mb temperatures warm about
1-2 degrees over Sunday under the shifting ridge. So today`s highs
should be 2 to 4 degrees warmer. However, for most, Tuesday looks
like the warmest day. Through Tuesday the mid-level ridge shifts
toward western Montana, a mid-level trough and its leading cold
front approach the coast and the flow turns southwesterly with
WAA. So highs look to be another 2 to 4 degrees milder than today,
meaning mid 70s to lower 80s (or about 10 to 15 degrees above
normal). The exception will be near the Cascades with the
increasing onshore flow, leaving that area slightly cooler as
compared to Monday. The incoming cold front will also bring some
clouds and a chance of rain to the Cascade crest Tuesday
afternoon, maybe a stray clap or thunder. Otherwise the region
looks dry and mostly clear. /J. Cote`

Tues Nt through Mon: With similar timing between the
GFS/ECMWF/NAM that the frontal and upper trof passage will take
place Tues Nt through Wed Nt, we tried to fine tune the temporal
specifics a bit but, more importantly, lowered snow levels and
cooled temperatures. The degree of cooling, areal coverage of
thunder potential, and snow/graupel chances will be highly
dependent upon the strength of the upper trough. In the latest
model runs, the GFS is much deeper (and slower) with the upper
low Wed evening over the Idaho Panhandle, which is the outlier.
Therefore, we did not increase pcpn amnts significantly for the NE
Wa and N Idaho Panhandle zones. The thunder threat still looks
likely Wed though, based on soundings, the threat may be more for
graupel than a meaningful thunder event. The second wave moving
into the region for Fri shows the ECMWF as the cooler and much
deeper wave (compared to the GFS), but both similar in character
as far as sensible weather as the Wed wave. Given these continued
uncertainties, which has been the case for the last five to ten
model runs, we simply trended cooler with more showers and
slightly lower snow levels. bz


&&

.AVIATION...
06Z TAFS: High pressure building into the region will result in
VFR conditions through 06Z Tuesday. Winds will remain weak and
some passing high cirrus can be expected to drop south into the
region out of BC. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        72  46  75  50  65  41 /   0   0  10  10  20  30
Coeur d`Alene  70  41  75  44  65  41 /   0   0  10  10  30  30
Pullman        69  42  74  46  64  39 /   0   0  10  10  20  20
Lewiston       76  46  78  49  70  43 /   0   0   0  10  20  20
Colville       75  42  77  46  68  43 /   0   0  10  10  40  30
Sandpoint      69  38  73  40  67  39 /   0   0  10  10  40  40
Kellogg        68  40  74  43  67  39 /   0   0  10  10  40  30
Moses Lake     77  44  78  50  67  41 /   0   0  10  10  20  10
Wenatchee      77  51  77  53  66  43 /   0   0  10  10  20  10
Omak           77  44  77  47  66  40 /   0   0  10  10  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&

$$




000
FXUS66 KPQR 200924
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
224 AM PDT MON APR 20 2015

.SYNOPSIS...HIGH PRESSURE WILL CONTINUE TO PROVIDE UNSEASONABLY
WARM WEATHER TO THE PACIFIC NORTHWEST TODAY. THE RIDGE WILL SHIFT
INLAND TONIGHT AS AN UPPER TROUGH NEARS...ALLOWING A DEEPER MARINE
LAYER TO DEVELOP. THIS WILL BEGIN A SIGNIFICANT COOL DOWN FOR TUESDAY
AS LOW CLOUDS PUSH ONSHORE AHEAD OF A WEAK COLD FRONT. AN UPPER LEVEL
TROUGH WILL LINGER THROUGH THE END OF THE WEEK...KEEPING
TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL.
&&

.SHORT TERM...TODAY THROUGH THURSDAY...WATER VAPOR IMAGERY SHOWS AN
AMPLIFIED UPPER RIDGE OVER THE PACIFIC NW WITH A BROAD TROUGH OVER
THE NE PACIFIC EARLY THIS MORNING. INFRARED IMAGERY SHOWS MOSTLY
CLEAR SKIES OVER THE AREA WITH JUST A FEW THIN AND HIGH CLOUDS
STREAMING OVER THE AREA. THERE IS A SLIVER OF MARINE STRATUS
APPROACHING THE CENTRAL OREGON COAST FROM THE SOUTH. TODAY WILL BE
MOSTLY SUNNY FOR THE PORTLAND FORECAST AREA...EXCEPT FOR THE MARINE
STRATUS THAT WILL FILL IN ALONG THE CENTRAL OREGON COAST. LOW MARINE
CLOUDS WILL WORK ITS WAY NORTHWARD ALONG THE COAST THIS MORNING AND
LIKELY REACH TILLAMOOK BY NOON. EXPECT THE STRATUS TO REACH ASTORIA
AND SW WASHINGTON COAST MID TO LATE AFTERNOON.

TEMPERATURES ARE THE MAIN FORECAST CHALLENGE FOR TODAY AS A THIN
LAYER OF SMOKE ALOFT FROM FIRES IN SIBERIA CONTINUES TO STREAM OVER
THE REGION. THIS SMOKE WAS THICK ENOUGH YESTERDAY TO LIMIT THERMAL
WARMING. HAVE LEANED TOWARDS PERSISTENCE FOR TODAYS TEMPERATURES
ALTHOUGH STILL THINK IT WILL BE 1 TO 2 DEGREES WARMER THAN SUNDAY
WITH THE UPPER RIDGE AXIS DIRECTLY OVER THE AREA. THE CENTRAL OREGON
COAST WILL BE MUCH COOLER TODAY WITH THE MARINE STRATUS...AND THE
TEMPERATURES WILL DEPEND ON THE TIMING OF THE MARINE INTRUSION.
GENERALLY EXPECT THE TEMPERATURES FOR THE CENTRAL OREGON COAST TO
REMAIN BELOW 60 DEGREES.

THE UPPER RIDGE WILL MOVE EAST OF THE CASCADES TONIGHT AND ONSHORE
FLOW WILL PUSH THE COOLER MARINE AIR INLAND EXPECT WIDESPREAD STRATUS
TUESDAY MORNING THAT WILL LINGER IN MOST LOCATIONS THROUGH TUESDAY
AFTERNOON. A WEAKENING FRONT WILL APPROACH THE COAST TUESDAY MORNING.
WEAK LIFT FROM THIS  FRONT WILL HELP THE STRATUS PRODUCE SOME DRIZZLE
ALONG THE COAST IN THE MORNING. THE FRONT...OR WHAT IS LEFT OF IT
WILL MOVE INLAND TUESDAY AFTERNOON AND POSSIBLY GENERATE SOME
AFTERNOON SHOWERS. THE DEEP MARINE LAYER WILL KEEP ANY
SHOWERS SHALLOW EXCEPT ALONG THE CASCADE CREST WHICH MAY REMAIN ABOVE
THE MARINE INVERSION...WHERE SOME WARMER SURFACE PARCELS MAY BE MORE
BUOYANT FOR DEEPER SHOWERS AND ISOLATED THUNDERSTORMS. THE CHANCE FOR
THUNDERSTORMS LOOKS VERY SLIM...BUT THE GREATS CHANCE LOOKS TO BE
ALONG THE CREST OF THE CENTRAL OREGON CASCADES.

TEMPERATURES WILL BE NOTICEABLY COOLER TUESDAY WITH INLAND HIGHS
EXPECTED IN THE MID TO UPPER 60S. MUCH COOLER AIR WILL MOVE IN
WEDNESDAY AS THE UPPER TROUGH SWINGS OVER THE AREA. THE TROUGH WILL
MAINTAIN A SLIGHT CHANCE OF SHOWERS FOR WEDNESDAY...MAINLY FOR THE
HIGHER TERRAIN. ANOTHER WEAK FRONT WILL MOVE ACROSS THE AREA THURSDAY
AND CONTINUE THE COOL AND SHOWERY WEATHER. TJ

.LONG TERM...THURSDAY NIGHT THROUGH SUNDAY...MODELS ARE STRUGGLING
WITH THE THE WEATHER DETAILS FOR THURSDAY NIGHT AND FRIDAY BUT
GENERALLY SHOW COOL ONSHORE FLOW CONTINUING SOME CHANCE FOR SHOWERS.
THE MODELS ARE IN FAIR AGREEMENT ON A MORE ORGANIZED FRONTAL SYSTEM
FOR THE WEEKEND...PERHAPS WITH A WEAK TO MODEST ATMOSPHERIC RIVER. TJ
&&

.AVIATION...VFR UNDER WITH DRY AIR MASS CONTINUES. AGAIN...WILL
HAVE PATCHY FOG/LOW STATUS IN COASTAL VALLEYS AND BAYS THIS AM.
CHANGE IN PATTERN STARTS LATER TODAY...AS ONSHORE FLOW BEGINS TO
STRENGTHEN. THIS WILL ALLOW STRATUS OF 600 TO 1000 FT TO PUSH UP
TO COAST BY 03Z. AS CLOUDS PUSH FURTHER INLAND TONIGHT...CIGS
WILL GRADUALLY LIFT TO LOW MVFR RANGE. LIKELY TO SEE AREAS OF LOW
CLOUDS IN WILLAMETTE VALLEY EARLY TUE AM.

KPDX AND APPROACHES...CLEAR AND DRY UNDER HIGH PRES. NO WEATHER
IMPACTS EXPECTED THROUGH THIS EVENING. WILL SEE AREAS OF LOW MVFR
STRATUS VERY LATE TONIGHT INTO TUE AM.     ROCKEY.
&&

.MARINE...WINDS CONTINUE TO GRADUALLY DIMINISH TONIGHT AS THE
THERMALLY INDUCED PRESSURE GRADIENT WEAKENS. WINDS WILL SUBSIDE
FURTHER TODAY AS A WEAK FRONT APPROACHES. THE FRONT WILL MOVE
ACROSS ON TUE AND SHOULD NOT CAUSE MUCH IN THE WAY OF MARINE
CONCERNS. THE NE PAC HIGH STRENGTHENS AGAIN MID-WEEK SIGNALING A
RETURN OF THE COASTAL THERMAL SURFACE LOW. THEN EXPECT A RETURN OF
THE GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS FOR TUE NIGHT AND
WED. THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT MOVES
ACROSS.

SEAS WILL REMAIN AROUND 7 FT THROUGH TUE. THE INCREASING WINDS
TUE NIGHT AND WED WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT
FOR A BRIEF PERIOD BEFORE THEY DROP BACK DOWN ON THU.  BONK.
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KOTX 200528
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1027 PM PDT SUN APR 19 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and cooler temperatures. After this, a number of potential waves
track across the Inland Northwest. The heaviest amounts of rain
will fall across North Idaho, with snow levels high enough to not
pose a threat to any regional passes.

&&

.DISCUSSION...
Tonight through Tuesday...Satellite indicates dry northwest flow
aloft under the east flank of an approaching upper level ridge.
This will be the main driver of sensible weather for the next two
days...featuring mainly clear skies...light winds and increasingly
warm temperatures with widespread low to mid 70s by Tuesday
afternoon. There is not much else to elaborate on for this period.

Tuesday night through Wednesday night...This period will bring a
change to the dry and warm weather stretch. Models are in
agreement in dragging a moderate strength upper level trough
through the region beginning with a chance of showers or a stray
thunderstorms Tuesday evening/night over the high Cascades with a
general spreading out of this precipitation risk through the
basin on Wednesday and into the Idaho Panhandle Wednesday night.
This does not look like a significant precipitation maker with
fairly weak dynamic support and marginal deep moisture
availability and instability. The ECMWF model is the most
aggressive and fastest model which implies a better chance of
showers and isolated afternoon and evening thunderstorms...while
the GFS is slower and weaker. While confidence is growing that
Wednesday will feature at least more clouds and slightly cooler
temperatures with a few showers...confidence is low regarding
which model is more plausible at this time. /Fugazzi

Thursday through Sunday: A weak front will move through the area
early Thursday. By Thur afternoon the GFS is showing some decent
instability along the border btwn ID and MT. Have kept
thunderstorms in through the afternoon hours. But thereafter the
models are not in very good agreement about the rest of the work
week and next weekend. The 12Z ECMWF brings a large trough of low
pressure through the Pacific Northwest late Thur night through
early Sat morning. It then builds a shortwave ridge over the area
for Saturday and Sunday. Whereas the 12Z gfs brings several
fairly weak waves through broad southwest flow through Sunday.
Needless to say there is high uncertainty in the extended period.
Kept chance of precipitation around average for this time of the
year....meaning a slight chance in most valleys and a chance of
precip in the mountains. Thursday daytime highs should be a few
degrees above average. Then through the remainder of the forecast
period temps will be right around average for this time of the
year. /Nisbet

&&

.AVIATION...
06Z TAFS: High pressure building into the region will result in
VFR conditions through 06Z Tuesday. Winds will remain weak and
some passing high cirrus can be expected to drop south into the
region out of BC. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        42  72  45  75  50  70 /   0   0   0   0  10  20
Coeur d`Alene  37  70  41  75  44  70 /   0   0   0   0  10  30
Pullman        39  69  40  74  46  67 /   0   0   0   0  10  20
Lewiston       44  76  46  78  49  72 /   0   0   0   0  10  20
Colville       40  74  41  77  46  73 /   0   0   0   0  10  30
Sandpoint      35  69  37  73  40  71 /   0   0   0   0  10  30
Kellogg        37  68  39  74  43  70 /   0   0   0   0  10  40
Moses Lake     42  76  43  78  50  74 /   0   0   0   0  10  20
Wenatchee      48  76  50  77  53  72 /   0   0   0  10  10  20
Omak           42  76  43  77  47  73 /   0   0   0  10  10  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&





000
FXUS66 KOTX 200528
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1027 PM PDT SUN APR 19 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and cooler temperatures. After this, a number of potential waves
track across the Inland Northwest. The heaviest amounts of rain
will fall across North Idaho, with snow levels high enough to not
pose a threat to any regional passes.

&&

.DISCUSSION...
Tonight through Tuesday...Satellite indicates dry northwest flow
aloft under the east flank of an approaching upper level ridge.
This will be the main driver of sensible weather for the next two
days...featuring mainly clear skies...light winds and increasingly
warm temperatures with widespread low to mid 70s by Tuesday
afternoon. There is not much else to elaborate on for this period.

Tuesday night through Wednesday night...This period will bring a
change to the dry and warm weather stretch. Models are in
agreement in dragging a moderate strength upper level trough
through the region beginning with a chance of showers or a stray
thunderstorms Tuesday evening/night over the high Cascades with a
general spreading out of this precipitation risk through the
basin on Wednesday and into the Idaho Panhandle Wednesday night.
This does not look like a significant precipitation maker with
fairly weak dynamic support and marginal deep moisture
availability and instability. The ECMWF model is the most
aggressive and fastest model which implies a better chance of
showers and isolated afternoon and evening thunderstorms...while
the GFS is slower and weaker. While confidence is growing that
Wednesday will feature at least more clouds and slightly cooler
temperatures with a few showers...confidence is low regarding
which model is more plausible at this time. /Fugazzi

Thursday through Sunday: A weak front will move through the area
early Thursday. By Thur afternoon the GFS is showing some decent
instability along the border btwn ID and MT. Have kept
thunderstorms in through the afternoon hours. But thereafter the
models are not in very good agreement about the rest of the work
week and next weekend. The 12Z ECMWF brings a large trough of low
pressure through the Pacific Northwest late Thur night through
early Sat morning. It then builds a shortwave ridge over the area
for Saturday and Sunday. Whereas the 12Z gfs brings several
fairly weak waves through broad southwest flow through Sunday.
Needless to say there is high uncertainty in the extended period.
Kept chance of precipitation around average for this time of the
year....meaning a slight chance in most valleys and a chance of
precip in the mountains. Thursday daytime highs should be a few
degrees above average. Then through the remainder of the forecast
period temps will be right around average for this time of the
year. /Nisbet

&&

.AVIATION...
06Z TAFS: High pressure building into the region will result in
VFR conditions through 06Z Tuesday. Winds will remain weak and
some passing high cirrus can be expected to drop south into the
region out of BC. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        42  72  45  75  50  70 /   0   0   0   0  10  20
Coeur d`Alene  37  70  41  75  44  70 /   0   0   0   0  10  30
Pullman        39  69  40  74  46  67 /   0   0   0   0  10  20
Lewiston       44  76  46  78  49  72 /   0   0   0   0  10  20
Colville       40  74  41  77  46  73 /   0   0   0   0  10  30
Sandpoint      35  69  37  73  40  71 /   0   0   0   0  10  30
Kellogg        37  68  39  74  43  70 /   0   0   0   0  10  40
Moses Lake     42  76  43  78  50  74 /   0   0   0   0  10  20
Wenatchee      48  76  50  77  53  72 /   0   0   0  10  10  20
Omak           42  76  43  77  47  73 /   0   0   0  10  10  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&




000
FXUS66 KSEW 200458
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
955 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
THE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...SATELLITE IMAGERY SHOWS UPPER LEVEL RIDGE OVER
WESTERN WASHINGTON WITH THE RIDGE AXIS STILL JUST OFFSHORE. HIGH
CLOUDS MOVING OVER THE TOP OF THE RIDGE MOVING ACROSS WESTERN
WASHINGTON WITH THE NORTHWESTERLY FLOW ALOFT. TEMPERATURES AT 9 PM
WERE IN THE UPPER 40S TO MID 60S.

UPPER LEVEL RIDGE AXIS MOVING OVER WESTERN WASHINGTON ON MONDAY.
WHILE THE 500 MB HEIGHTS DROP TEMPERATURES IN THE LOWER LEVELS
ACTUALLY WARM UP A TOUCH WITH THE 850 MB TEMPS PEAKING OUT AROUND
PLUS 12C. IN ADDITION THE NORTHERLY GRADIENTS WHICH HAVE CAPPED THE
HIGH TEMPERATURES THE LAST COUPLE DAYS WILL WEAKEN. SURFACE
GRADIENTS TURNING ONSHORE LATE IN THE AFTERNOON BUT THIS WILL BE TOO
LATE TO CUT DOWN ON THE MAX TEMPS OVER THE INTERIOR. THE COASTAL
SECTIONS WILL SEE ABOUT 5 DEGREES OF COOLING. FOR THE INTERIOR
MONDAY WILL BE THE WARMEST DAY IN THIS STRETCH WITH MANY PLACES FROM
SEATTLE SOUTHWARD GETTING INTO THE LOWER TO MID 70S. 60S WILL BE
COMMON OVER THE REMAINDER OF THE INTERIOR.

ONSHORE GRADIENTS INCREASING MONDAY NIGHT AS THE UPPER LEVEL RIDGE
AXIS MOVES EAST OF THE AREA. MODEL CROSS SECTIONS SHOW THE WINDS IN
THE LOWER LEVELS REMAINING LIGHT NORTHERLY WHICH WILL CUT DOWN THE
DEPTH OF THE MARINE LAYER OVER THE INTERIOR TUESDAY MORNING. BY
TUESDAY AFTERNOON A WEAK COLD FRONT OUT AHEAD OF AN APPROACHING
UPPER LEVEL TROUGH WILL MOVE THROUGH WESTERN WASHINGTON INCREASING
THE CLOUD COVER OVER THE AREA. NAM GUIDANCE CONTINUES TO SHOW MAX
TEMPS AT LEAST 5 DEGREES ABOVE NORMAL WHILE THE GFS IS COOLER THE
ECMWF IS THE COOLEST. THE CURRENT FORECAST IS TRENDED TOWARD THE
COOLER SOLUTIONS AND GIVEN THE ONSHORE FLOW AND WEAK FRONT THIS
LOOKS GOOD.

UPPER LEVEL TROUGH MOVING THROUGH WESTERN WASHINGTON ON WEDNESDAY
KEEPING PLENTY OF CLOUD COVER OVER THE AREA WITH A CHANCE OF
SHOWERS. HIGHS ON WEDNESDAY WILL RETURN TO NEAR NORMAL...MID 50S TO
LOWER 60S. CURRENT FORECAST HAS THE TRENDS COVERED. FELTON

.LONG TERM...PREVIOUS DISCUSSION FOLLOWS. THE EXTENDED PERIOD STILL
APPEARED COOL AND UNSETTLED...HOWEVER CONFIDENCE IN THE DETAILS WERE
NOT HIGH DUE TO LACK OF CONSISTENCY AND AGREEMENT IN THE MEDIUM
RANGE SOLUTIONS. ANTICIPATE NEAR OR SLIGHTLY BELOW NORMAL DAYTIME
TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE OVER THE PAC NW WILL LEAD TO DRY
AND STABLE WEATHER ACROSS WESTERN WA TONIGHT THROUGH MONDAY. THE
FLOW ALOFT IS NORTHWESTERLY. VFR CONDITIONS ARE EXPECTED. SKIES WILL
REMAIN MOSTLY CLEAR WITH JUST FEW-SCT CIRRUS ALOFT. 33

KSEA...VFR CONDITIONS TONIGHT THROUGH MON. EXPECT N WINDS TO 10 KT.
33

&&

.MARINE...LOW PRESSURE ALONG THE COAST WILL MAINTAIN NORTHERLY FLOW
ACROSS WESTERN WA THROUGH MON. LOW PRES WILL SHIFT INLAND MON NIGHT
WITH WEAK ONSHORE FLOW DEVELOPING. ONSHORE FLOW WILL INCREASE ON TUE
AS A COLD FRONT MOVES INLAND...SMALL CRAFT ADVISORY WINDS ARE LIKELY
OVER THE COASTAL WATERS AND STRAIT OF JUAN DE FUCA. ONSHORE FLOW
WILL CONTINUE THROUGH THE END OF THE WEEK. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML








000
FXUS66 KSEW 200458
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
955 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
THE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...SATELLITE IMAGERY SHOWS UPPER LEVEL RIDGE OVER
WESTERN WASHINGTON WITH THE RIDGE AXIS STILL JUST OFFSHORE. HIGH
CLOUDS MOVING OVER THE TOP OF THE RIDGE MOVING ACROSS WESTERN
WASHINGTON WITH THE NORTHWESTERLY FLOW ALOFT. TEMPERATURES AT 9 PM
WERE IN THE UPPER 40S TO MID 60S.

UPPER LEVEL RIDGE AXIS MOVING OVER WESTERN WASHINGTON ON MONDAY.
WHILE THE 500 MB HEIGHTS DROP TEMPERATURES IN THE LOWER LEVELS
ACTUALLY WARM UP A TOUCH WITH THE 850 MB TEMPS PEAKING OUT AROUND
PLUS 12C. IN ADDITION THE NORTHERLY GRADIENTS WHICH HAVE CAPPED THE
HIGH TEMPERATURES THE LAST COUPLE DAYS WILL WEAKEN. SURFACE
GRADIENTS TURNING ONSHORE LATE IN THE AFTERNOON BUT THIS WILL BE TOO
LATE TO CUT DOWN ON THE MAX TEMPS OVER THE INTERIOR. THE COASTAL
SECTIONS WILL SEE ABOUT 5 DEGREES OF COOLING. FOR THE INTERIOR
MONDAY WILL BE THE WARMEST DAY IN THIS STRETCH WITH MANY PLACES FROM
SEATTLE SOUTHWARD GETTING INTO THE LOWER TO MID 70S. 60S WILL BE
COMMON OVER THE REMAINDER OF THE INTERIOR.

ONSHORE GRADIENTS INCREASING MONDAY NIGHT AS THE UPPER LEVEL RIDGE
AXIS MOVES EAST OF THE AREA. MODEL CROSS SECTIONS SHOW THE WINDS IN
THE LOWER LEVELS REMAINING LIGHT NORTHERLY WHICH WILL CUT DOWN THE
DEPTH OF THE MARINE LAYER OVER THE INTERIOR TUESDAY MORNING. BY
TUESDAY AFTERNOON A WEAK COLD FRONT OUT AHEAD OF AN APPROACHING
UPPER LEVEL TROUGH WILL MOVE THROUGH WESTERN WASHINGTON INCREASING
THE CLOUD COVER OVER THE AREA. NAM GUIDANCE CONTINUES TO SHOW MAX
TEMPS AT LEAST 5 DEGREES ABOVE NORMAL WHILE THE GFS IS COOLER THE
ECMWF IS THE COOLEST. THE CURRENT FORECAST IS TRENDED TOWARD THE
COOLER SOLUTIONS AND GIVEN THE ONSHORE FLOW AND WEAK FRONT THIS
LOOKS GOOD.

UPPER LEVEL TROUGH MOVING THROUGH WESTERN WASHINGTON ON WEDNESDAY
KEEPING PLENTY OF CLOUD COVER OVER THE AREA WITH A CHANCE OF
SHOWERS. HIGHS ON WEDNESDAY WILL RETURN TO NEAR NORMAL...MID 50S TO
LOWER 60S. CURRENT FORECAST HAS THE TRENDS COVERED. FELTON

.LONG TERM...PREVIOUS DISCUSSION FOLLOWS. THE EXTENDED PERIOD STILL
APPEARED COOL AND UNSETTLED...HOWEVER CONFIDENCE IN THE DETAILS WERE
NOT HIGH DUE TO LACK OF CONSISTENCY AND AGREEMENT IN THE MEDIUM
RANGE SOLUTIONS. ANTICIPATE NEAR OR SLIGHTLY BELOW NORMAL DAYTIME
TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE OVER THE PAC NW WILL LEAD TO DRY
AND STABLE WEATHER ACROSS WESTERN WA TONIGHT THROUGH MONDAY. THE
FLOW ALOFT IS NORTHWESTERLY. VFR CONDITIONS ARE EXPECTED. SKIES WILL
REMAIN MOSTLY CLEAR WITH JUST FEW-SCT CIRRUS ALOFT. 33

KSEA...VFR CONDITIONS TONIGHT THROUGH MON. EXPECT N WINDS TO 10 KT.
33

&&

.MARINE...LOW PRESSURE ALONG THE COAST WILL MAINTAIN NORTHERLY FLOW
ACROSS WESTERN WA THROUGH MON. LOW PRES WILL SHIFT INLAND MON NIGHT
WITH WEAK ONSHORE FLOW DEVELOPING. ONSHORE FLOW WILL INCREASE ON TUE
AS A COLD FRONT MOVES INLAND...SMALL CRAFT ADVISORY WINDS ARE LIKELY
OVER THE COASTAL WATERS AND STRAIT OF JUAN DE FUCA. ONSHORE FLOW
WILL CONTINUE THROUGH THE END OF THE WEEK. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML









000
FXUS66 KSEW 200458
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
955 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
THE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...SATELLITE IMAGERY SHOWS UPPER LEVEL RIDGE OVER
WESTERN WASHINGTON WITH THE RIDGE AXIS STILL JUST OFFSHORE. HIGH
CLOUDS MOVING OVER THE TOP OF THE RIDGE MOVING ACROSS WESTERN
WASHINGTON WITH THE NORTHWESTERLY FLOW ALOFT. TEMPERATURES AT 9 PM
WERE IN THE UPPER 40S TO MID 60S.

UPPER LEVEL RIDGE AXIS MOVING OVER WESTERN WASHINGTON ON MONDAY.
WHILE THE 500 MB HEIGHTS DROP TEMPERATURES IN THE LOWER LEVELS
ACTUALLY WARM UP A TOUCH WITH THE 850 MB TEMPS PEAKING OUT AROUND
PLUS 12C. IN ADDITION THE NORTHERLY GRADIENTS WHICH HAVE CAPPED THE
HIGH TEMPERATURES THE LAST COUPLE DAYS WILL WEAKEN. SURFACE
GRADIENTS TURNING ONSHORE LATE IN THE AFTERNOON BUT THIS WILL BE TOO
LATE TO CUT DOWN ON THE MAX TEMPS OVER THE INTERIOR. THE COASTAL
SECTIONS WILL SEE ABOUT 5 DEGREES OF COOLING. FOR THE INTERIOR
MONDAY WILL BE THE WARMEST DAY IN THIS STRETCH WITH MANY PLACES FROM
SEATTLE SOUTHWARD GETTING INTO THE LOWER TO MID 70S. 60S WILL BE
COMMON OVER THE REMAINDER OF THE INTERIOR.

ONSHORE GRADIENTS INCREASING MONDAY NIGHT AS THE UPPER LEVEL RIDGE
AXIS MOVES EAST OF THE AREA. MODEL CROSS SECTIONS SHOW THE WINDS IN
THE LOWER LEVELS REMAINING LIGHT NORTHERLY WHICH WILL CUT DOWN THE
DEPTH OF THE MARINE LAYER OVER THE INTERIOR TUESDAY MORNING. BY
TUESDAY AFTERNOON A WEAK COLD FRONT OUT AHEAD OF AN APPROACHING
UPPER LEVEL TROUGH WILL MOVE THROUGH WESTERN WASHINGTON INCREASING
THE CLOUD COVER OVER THE AREA. NAM GUIDANCE CONTINUES TO SHOW MAX
TEMPS AT LEAST 5 DEGREES ABOVE NORMAL WHILE THE GFS IS COOLER THE
ECMWF IS THE COOLEST. THE CURRENT FORECAST IS TRENDED TOWARD THE
COOLER SOLUTIONS AND GIVEN THE ONSHORE FLOW AND WEAK FRONT THIS
LOOKS GOOD.

UPPER LEVEL TROUGH MOVING THROUGH WESTERN WASHINGTON ON WEDNESDAY
KEEPING PLENTY OF CLOUD COVER OVER THE AREA WITH A CHANCE OF
SHOWERS. HIGHS ON WEDNESDAY WILL RETURN TO NEAR NORMAL...MID 50S TO
LOWER 60S. CURRENT FORECAST HAS THE TRENDS COVERED. FELTON

.LONG TERM...PREVIOUS DISCUSSION FOLLOWS. THE EXTENDED PERIOD STILL
APPEARED COOL AND UNSETTLED...HOWEVER CONFIDENCE IN THE DETAILS WERE
NOT HIGH DUE TO LACK OF CONSISTENCY AND AGREEMENT IN THE MEDIUM
RANGE SOLUTIONS. ANTICIPATE NEAR OR SLIGHTLY BELOW NORMAL DAYTIME
TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE OVER THE PAC NW WILL LEAD TO DRY
AND STABLE WEATHER ACROSS WESTERN WA TONIGHT THROUGH MONDAY. THE
FLOW ALOFT IS NORTHWESTERLY. VFR CONDITIONS ARE EXPECTED. SKIES WILL
REMAIN MOSTLY CLEAR WITH JUST FEW-SCT CIRRUS ALOFT. 33

KSEA...VFR CONDITIONS TONIGHT THROUGH MON. EXPECT N WINDS TO 10 KT.
33

&&

.MARINE...LOW PRESSURE ALONG THE COAST WILL MAINTAIN NORTHERLY FLOW
ACROSS WESTERN WA THROUGH MON. LOW PRES WILL SHIFT INLAND MON NIGHT
WITH WEAK ONSHORE FLOW DEVELOPING. ONSHORE FLOW WILL INCREASE ON TUE
AS A COLD FRONT MOVES INLAND...SMALL CRAFT ADVISORY WINDS ARE LIKELY
OVER THE COASTAL WATERS AND STRAIT OF JUAN DE FUCA. ONSHORE FLOW
WILL CONTINUE THROUGH THE END OF THE WEEK. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML









000
FXUS66 KSEW 200458
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
955 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
THE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...SATELLITE IMAGERY SHOWS UPPER LEVEL RIDGE OVER
WESTERN WASHINGTON WITH THE RIDGE AXIS STILL JUST OFFSHORE. HIGH
CLOUDS MOVING OVER THE TOP OF THE RIDGE MOVING ACROSS WESTERN
WASHINGTON WITH THE NORTHWESTERLY FLOW ALOFT. TEMPERATURES AT 9 PM
WERE IN THE UPPER 40S TO MID 60S.

UPPER LEVEL RIDGE AXIS MOVING OVER WESTERN WASHINGTON ON MONDAY.
WHILE THE 500 MB HEIGHTS DROP TEMPERATURES IN THE LOWER LEVELS
ACTUALLY WARM UP A TOUCH WITH THE 850 MB TEMPS PEAKING OUT AROUND
PLUS 12C. IN ADDITION THE NORTHERLY GRADIENTS WHICH HAVE CAPPED THE
HIGH TEMPERATURES THE LAST COUPLE DAYS WILL WEAKEN. SURFACE
GRADIENTS TURNING ONSHORE LATE IN THE AFTERNOON BUT THIS WILL BE TOO
LATE TO CUT DOWN ON THE MAX TEMPS OVER THE INTERIOR. THE COASTAL
SECTIONS WILL SEE ABOUT 5 DEGREES OF COOLING. FOR THE INTERIOR
MONDAY WILL BE THE WARMEST DAY IN THIS STRETCH WITH MANY PLACES FROM
SEATTLE SOUTHWARD GETTING INTO THE LOWER TO MID 70S. 60S WILL BE
COMMON OVER THE REMAINDER OF THE INTERIOR.

ONSHORE GRADIENTS INCREASING MONDAY NIGHT AS THE UPPER LEVEL RIDGE
AXIS MOVES EAST OF THE AREA. MODEL CROSS SECTIONS SHOW THE WINDS IN
THE LOWER LEVELS REMAINING LIGHT NORTHERLY WHICH WILL CUT DOWN THE
DEPTH OF THE MARINE LAYER OVER THE INTERIOR TUESDAY MORNING. BY
TUESDAY AFTERNOON A WEAK COLD FRONT OUT AHEAD OF AN APPROACHING
UPPER LEVEL TROUGH WILL MOVE THROUGH WESTERN WASHINGTON INCREASING
THE CLOUD COVER OVER THE AREA. NAM GUIDANCE CONTINUES TO SHOW MAX
TEMPS AT LEAST 5 DEGREES ABOVE NORMAL WHILE THE GFS IS COOLER THE
ECMWF IS THE COOLEST. THE CURRENT FORECAST IS TRENDED TOWARD THE
COOLER SOLUTIONS AND GIVEN THE ONSHORE FLOW AND WEAK FRONT THIS
LOOKS GOOD.

UPPER LEVEL TROUGH MOVING THROUGH WESTERN WASHINGTON ON WEDNESDAY
KEEPING PLENTY OF CLOUD COVER OVER THE AREA WITH A CHANCE OF
SHOWERS. HIGHS ON WEDNESDAY WILL RETURN TO NEAR NORMAL...MID 50S TO
LOWER 60S. CURRENT FORECAST HAS THE TRENDS COVERED. FELTON

.LONG TERM...PREVIOUS DISCUSSION FOLLOWS. THE EXTENDED PERIOD STILL
APPEARED COOL AND UNSETTLED...HOWEVER CONFIDENCE IN THE DETAILS WERE
NOT HIGH DUE TO LACK OF CONSISTENCY AND AGREEMENT IN THE MEDIUM
RANGE SOLUTIONS. ANTICIPATE NEAR OR SLIGHTLY BELOW NORMAL DAYTIME
TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE OVER THE PAC NW WILL LEAD TO DRY
AND STABLE WEATHER ACROSS WESTERN WA TONIGHT THROUGH MONDAY. THE
FLOW ALOFT IS NORTHWESTERLY. VFR CONDITIONS ARE EXPECTED. SKIES WILL
REMAIN MOSTLY CLEAR WITH JUST FEW-SCT CIRRUS ALOFT. 33

KSEA...VFR CONDITIONS TONIGHT THROUGH MON. EXPECT N WINDS TO 10 KT.
33

&&

.MARINE...LOW PRESSURE ALONG THE COAST WILL MAINTAIN NORTHERLY FLOW
ACROSS WESTERN WA THROUGH MON. LOW PRES WILL SHIFT INLAND MON NIGHT
WITH WEAK ONSHORE FLOW DEVELOPING. ONSHORE FLOW WILL INCREASE ON TUE
AS A COLD FRONT MOVES INLAND...SMALL CRAFT ADVISORY WINDS ARE LIKELY
OVER THE COASTAL WATERS AND STRAIT OF JUAN DE FUCA. ONSHORE FLOW
WILL CONTINUE THROUGH THE END OF THE WEEK. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML








000
FXUS66 KPQR 200332
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
830 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL CONTINUE TO PROVIDE UNSEASONABLY
WARM WEATHER TO THE PACIFIC NORTHWEST MONDAY. THERMAL LOW PRESSURE
WILL SHIFT INLAND MONDAY...ALLOWING A DEEPER MARINE LAYER TO DEVELOP
ALONG THE COAST BY LATE AFTERNOON. THIS WILL BEGIN A SIGNIFICANT
COOLDOWN FOR TUESDAY AS THE DEEP MARINE LAYER PUSHES ONSHORE AHEAD OF
AN INCOMING COLD FRONT. AN UPPER LEVEL TROUGH WILL THEN LINGER
THROUGH THE END OF THE WEEK...KEEPING TEMPERATURES NEAR OR SLIGHTLY
BELOW NORMAL.

&&

.SHORT TERM...TONIGHT THROUGH WEDNESDAY...IT APPEARS THE SIBERIAN
WILDFIRE SMOKE HAD SOME IMPACT ON MAX TEMPERATURES TODAY. DESPITE A
SLIGHTLY WARMER START AND A 12.6C 850 MB TEMP FROM THE 00Z KSLE
SOUNDING...TEMPS WERE QUITE SIMILAR TO YESTERDAY IN MOST PLACES. THE
SRN WILLAMETTE VALLEY HAD 3-5 DEGREE WARMING WITH LESS NORTH SURFACE
GRADIENT TODAY. ALSO...PREVIOUS FORECASTER NOTED THAT RAWS STATIONS
SHOWED A 5-10 PERCENT LOSS OF INSOLATION IN THE MID TO LATE AFTERNOON
HOURS. NO OFFICIAL REPORTING SITE WITHIN THE FORECAST AREA (SEE
PDXRTPOR) HIT 80 TODAY. KMMV WAS CLOSEST AT 79.

THE LATEST NAM HAS CHANGED A BIT FROM 24 HRS AGO. THE 00Z RUN NOW HAS
THE THERMALLY-INDUCED SURFACE LOW CENTERED FROM THE EAST SLOPES OF
THE OREGON COAST RANGE AND THE SW WASHINGTON WILLAPA HILLS TO THE
WILLAMETTE VALLEY AND CLARK COUNTY IN SW WA 12Z MON. THE NAM THEN
SHIFTS THIS FEATURE TO THE CASCADE CREST BY 21Z MON. TYPICALLY...THE
MODELS TEND TO BE A LITTLE TOO FAST MOVING THE THERMAL LOW EAST. THE
12Z HI RES ARW MODEL SHOWS INCREASING BOUNDARY LAYER MOISTURE ALONG
THE CENTRAL COAST BY 18Z MON. EXPECT FOG AND LOW STRATUS TO WORK UP
THE COAST MON MORNING...BUT WILL LIKELY NOT GET TO KAST OR THE S WA
COAST UNTIL MID TO LATE AFTERNOON.

NESDIS ANALYSTS BELIEVE THE SMOKE WILL BE LESS APPARENT MONDAY...
STAYING TO OUR NORTH AS THE UPPER RIDGE AXIS MOVES INTO THE PAC NW.
THEREFORE EXPECT PLENTY OF SUNSHINE AGAIN MONDAY FOR THE INLAND
AREAS. MODELS SHOW 500 MB HEIGHTS DECREASING A BIT MONDAY. THE 00Z
NAM AND GFS MAINTAIN 850 MB TEMPS OF 12-14C INLAND 00Z TUE. BASED ON
TODAYS MAX TEMPS...NUDGED MON VALUES DOWN A COUPLE DEGREES...BUT
STILL GOING FOR 80 IN THE N WILLAMETTE VALLEY...WRN CLARK COUNTY AND
IN THE GORGE. THIS IS DUE TO THE FORECAST LOCATION OF THE THERMAL
TROUGH...PLENTY OF SUNSHINE...AND LESS SMOKE ALOFT. THE TRICKY AREAS
WILL BE THE FAR SRN WILLAMETTE VALLEY AND THE CENTRAL OREGON COAST
RANGE. THESE AREAS SHOULD BE THE FIRST TO EXPERIENCE MARINE AIR
SEEPAGE WHICH WILL CAP MAX TEMPS.

THE HI RES ARW THEN SHOWS 90 PCT OR GREATER BOUNDARY LAYER MOISTURE
PUSHING UP THE COASTAL DRAINAGES MON EVENING...THEN SPREADING DOWN
THE COLUMBIA RIVER AND THROUGH THE MAJOR GAPS ON THE CENTRAL COAST
RANGE 06Z-12Z TUE. NAM CROSS SECTIONS SHOW A DEEP MARINE LAYER
PUSHING IN MONDAY NIGHT AND EARLY TUE... WITH THE POTENTIAL FOR
ISOLATED SHOWERS TUE AFTERNOON AS THE MARINE LAYER MIXES/TURNS OVER.
TEMPS WILL BE 10-15 DEGREES COOLER TUESDAY DUE TO THE DEEP ONSHORE
FLOW AND MARINE INFLUENCE. THE DEEP MARINE LAYER WILL KEEP ANY
SHOWERS SHALLOW EXCEPT ALONG THE CASCADE CREST WHICH MAY REMAIN ABOVE
THE MARINE INVERSION...WHERE SOME WARMER SURFACE PARCELS MAY BE MORE
BUOYANT FOR DEEPER SHOWERS AND ISOLATED THUNDERSTORMS. MODEL
SOUNDINGS IN THE CASCADES DO NOT LOOK ALL THAT IMPRESSIVE FOR
CONVECTIVE DEVELOPMENT...BUT THE 00Z NAM DOES DEVELOP SOME QPF NEAR
THE CREST OF THE LANE COUNTY CASCADES TUE AFTERNOON. BELIEVE THE 700
MB FLOW WILL BE A BIT TOO SWLY AND KEEP ANY CELLS JUST EAST OF THE
CREST. A SIMILAR SITUATION IS EXPECTED WEDNESDAY...WITH A
DEEP MARINE LAYER...BUT PERHAPS A LITTLE MORE OF A TRIGGER FOR
SHOWERS AS THE UPPER TROUGH AXIS DRAGS ACROSS THE PAC NW. ONCE TEMPS
COOL DOWN TUESDAY...EXPECT NEAR TO SLIGHTLY BELOW NORMAL TEMPS TO
PERSIST FOR SEVERAL DAYS.  WEISHAAR

.LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY...MODELS ARE HAVING A
HARD TIME WITH THE DETAILS OF WHAT IS LEFT BEHIND AS THE INCOMING
UPPER TROUGH FALLS APART OVER THE PACIFIC NORTHWEST MIDDLE TO LATE
THIS UPCOMING WEEK. IT APPEARS THERE WILL BE ENOUGH OF A WEAKNESS IN
500 MB HEIGHTS AND JUST ENOUGH COOL AIR ALOFT TO MAKE IT DIFFICULT TO
COMPLETELY RULE OUT SHOWERS ANYTIME BETWEEN WED-FRI. 12Z GEM/EC SHOW
A COLD FRONT HOLDING TOGETHER ENOUGH TO BRING A MORE ORGANIZED CHANCE
OF SHOWERS TO OUR NORTHERN ZONES THU NIGHT/FRI. HOWEVER THE 12Z GFS
HAS THIS SYSTEM FALLING APART BEFORE MOVING ONSHORE. RAIN CHANCES
INCREASE NEXT WEEKEND AS MODELS AGREE ON A STRONGER FRONTAL SYSTEM
MOVING ONSHORE...PERHAPS WITH A WEAK TO MODEST ATMOSPHERIC RIVER.
CONFIDENCE IS HIGH ONE THING...AFTER THIS MONDAY THE NEAR- RECORD
WARMTH WILL BE HISTORY AND TEMPS WILL BE MUCH CLOSER TO LATE APRIL
NORMALS.  WEAGLE

&&

.AVIATION...CONTINUED VFR THROUGH 21/06Z...EXCEPT AT THE COAST
WHERE PATCHY FOG MAY AGAIN DEVELOP BETWEEN 10Z AND 15Z. EXPECT THE
COAST WILL RETURN TO VFR FOR THE BULK OF DAYLIGHT HOURS BUT AM
SEEING INDICATIONS FROM THE 12Z WRF ARW HIGH RESOLUTION MODEL OF
A FOG/STRATUS DECK REACHING THE COAST BETWEEN 21/00 AND 21/03Z.
WILL WAIT FOR THE 00Z RUN BEFORE COMMITTING TO THE TAF.

KPDX AND APPROACHES...CLEAR AND DRY UNDER HIGH PRES. NO WEATHER
IMPACTS EXPECTED THROUGH MON. /JBONK


&&

.MARINE...WINDS CONTINUE TO GRADUALLY DIMINISH TONIGHT AS THE
THERMALLY INDUCED PRESSURE GRADIENT WEAKENS. STILL EXPECT
NORTHERLY GUSTS 20 TO 25 KT THROUGH 5 AM MONDAY. WINDS WILL
SUBSIDE FURTHER DURING THE DAY MON AS A WEAK FRONT APPROACHES AND
SHUNTS THE UPPER RIDGE EAST ACROSS THE CASCADES.THE FRONT WILL MOVE
ACROSS ON TUE AND SHOULD NOT CAUSE MUCH IN THE WAY OF MARINE
CONCERNS. THE NE PAC HIGH STRENGTHENS AGAIN MID-WEEK SIGNALING A
RETURN OF THE COASTAL THERMAL SURFACE LOW. THEN EXPECT A RETURN OF
THE GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS FOR TUE NIGHT AND WED.
THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT MOVES ACROSS.

SEAS WILL REMAIN AROUND 7 FT THROUGH TUE. THE INCREASING WINDS
TUE NIGHT AND WED WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT
FOR A BRIEF PERIOD BEFORE THEY DROP BACK DOWN ON THU.

HAVE DECIDED TO DROP THE SMALL CRAFT ADVISORY FOR THE COLUMBIA
BAR COVERING THE EBB AROUND SUNRISE MON. CONDITIONS REPORTED BY
THE COAST GUARD HAVE BEEN SIGNIFICANTLY UNDER PERFORMING THE
LOCAL MODEL OUTPUT. JBONK

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 AM PDT MONDAY FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT
     60 NM.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 200332
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
830 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL CONTINUE TO PROVIDE UNSEASONABLY
WARM WEATHER TO THE PACIFIC NORTHWEST MONDAY. THERMAL LOW PRESSURE
WILL SHIFT INLAND MONDAY...ALLOWING A DEEPER MARINE LAYER TO DEVELOP
ALONG THE COAST BY LATE AFTERNOON. THIS WILL BEGIN A SIGNIFICANT
COOLDOWN FOR TUESDAY AS THE DEEP MARINE LAYER PUSHES ONSHORE AHEAD OF
AN INCOMING COLD FRONT. AN UPPER LEVEL TROUGH WILL THEN LINGER
THROUGH THE END OF THE WEEK...KEEPING TEMPERATURES NEAR OR SLIGHTLY
BELOW NORMAL.

&&

.SHORT TERM...TONIGHT THROUGH WEDNESDAY...IT APPEARS THE SIBERIAN
WILDFIRE SMOKE HAD SOME IMPACT ON MAX TEMPERATURES TODAY. DESPITE A
SLIGHTLY WARMER START AND A 12.6C 850 MB TEMP FROM THE 00Z KSLE
SOUNDING...TEMPS WERE QUITE SIMILAR TO YESTERDAY IN MOST PLACES. THE
SRN WILLAMETTE VALLEY HAD 3-5 DEGREE WARMING WITH LESS NORTH SURFACE
GRADIENT TODAY. ALSO...PREVIOUS FORECASTER NOTED THAT RAWS STATIONS
SHOWED A 5-10 PERCENT LOSS OF INSOLATION IN THE MID TO LATE AFTERNOON
HOURS. NO OFFICIAL REPORTING SITE WITHIN THE FORECAST AREA (SEE
PDXRTPOR) HIT 80 TODAY. KMMV WAS CLOSEST AT 79.

THE LATEST NAM HAS CHANGED A BIT FROM 24 HRS AGO. THE 00Z RUN NOW HAS
THE THERMALLY-INDUCED SURFACE LOW CENTERED FROM THE EAST SLOPES OF
THE OREGON COAST RANGE AND THE SW WASHINGTON WILLAPA HILLS TO THE
WILLAMETTE VALLEY AND CLARK COUNTY IN SW WA 12Z MON. THE NAM THEN
SHIFTS THIS FEATURE TO THE CASCADE CREST BY 21Z MON. TYPICALLY...THE
MODELS TEND TO BE A LITTLE TOO FAST MOVING THE THERMAL LOW EAST. THE
12Z HI RES ARW MODEL SHOWS INCREASING BOUNDARY LAYER MOISTURE ALONG
THE CENTRAL COAST BY 18Z MON. EXPECT FOG AND LOW STRATUS TO WORK UP
THE COAST MON MORNING...BUT WILL LIKELY NOT GET TO KAST OR THE S WA
COAST UNTIL MID TO LATE AFTERNOON.

NESDIS ANALYSTS BELIEVE THE SMOKE WILL BE LESS APPARENT MONDAY...
STAYING TO OUR NORTH AS THE UPPER RIDGE AXIS MOVES INTO THE PAC NW.
THEREFORE EXPECT PLENTY OF SUNSHINE AGAIN MONDAY FOR THE INLAND
AREAS. MODELS SHOW 500 MB HEIGHTS DECREASING A BIT MONDAY. THE 00Z
NAM AND GFS MAINTAIN 850 MB TEMPS OF 12-14C INLAND 00Z TUE. BASED ON
TODAYS MAX TEMPS...NUDGED MON VALUES DOWN A COUPLE DEGREES...BUT
STILL GOING FOR 80 IN THE N WILLAMETTE VALLEY...WRN CLARK COUNTY AND
IN THE GORGE. THIS IS DUE TO THE FORECAST LOCATION OF THE THERMAL
TROUGH...PLENTY OF SUNSHINE...AND LESS SMOKE ALOFT. THE TRICKY AREAS
WILL BE THE FAR SRN WILLAMETTE VALLEY AND THE CENTRAL OREGON COAST
RANGE. THESE AREAS SHOULD BE THE FIRST TO EXPERIENCE MARINE AIR
SEEPAGE WHICH WILL CAP MAX TEMPS.

THE HI RES ARW THEN SHOWS 90 PCT OR GREATER BOUNDARY LAYER MOISTURE
PUSHING UP THE COASTAL DRAINAGES MON EVENING...THEN SPREADING DOWN
THE COLUMBIA RIVER AND THROUGH THE MAJOR GAPS ON THE CENTRAL COAST
RANGE 06Z-12Z TUE. NAM CROSS SECTIONS SHOW A DEEP MARINE LAYER
PUSHING IN MONDAY NIGHT AND EARLY TUE... WITH THE POTENTIAL FOR
ISOLATED SHOWERS TUE AFTERNOON AS THE MARINE LAYER MIXES/TURNS OVER.
TEMPS WILL BE 10-15 DEGREES COOLER TUESDAY DUE TO THE DEEP ONSHORE
FLOW AND MARINE INFLUENCE. THE DEEP MARINE LAYER WILL KEEP ANY
SHOWERS SHALLOW EXCEPT ALONG THE CASCADE CREST WHICH MAY REMAIN ABOVE
THE MARINE INVERSION...WHERE SOME WARMER SURFACE PARCELS MAY BE MORE
BUOYANT FOR DEEPER SHOWERS AND ISOLATED THUNDERSTORMS. MODEL
SOUNDINGS IN THE CASCADES DO NOT LOOK ALL THAT IMPRESSIVE FOR
CONVECTIVE DEVELOPMENT...BUT THE 00Z NAM DOES DEVELOP SOME QPF NEAR
THE CREST OF THE LANE COUNTY CASCADES TUE AFTERNOON. BELIEVE THE 700
MB FLOW WILL BE A BIT TOO SWLY AND KEEP ANY CELLS JUST EAST OF THE
CREST. A SIMILAR SITUATION IS EXPECTED WEDNESDAY...WITH A
DEEP MARINE LAYER...BUT PERHAPS A LITTLE MORE OF A TRIGGER FOR
SHOWERS AS THE UPPER TROUGH AXIS DRAGS ACROSS THE PAC NW. ONCE TEMPS
COOL DOWN TUESDAY...EXPECT NEAR TO SLIGHTLY BELOW NORMAL TEMPS TO
PERSIST FOR SEVERAL DAYS.  WEISHAAR

.LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY...MODELS ARE HAVING A
HARD TIME WITH THE DETAILS OF WHAT IS LEFT BEHIND AS THE INCOMING
UPPER TROUGH FALLS APART OVER THE PACIFIC NORTHWEST MIDDLE TO LATE
THIS UPCOMING WEEK. IT APPEARS THERE WILL BE ENOUGH OF A WEAKNESS IN
500 MB HEIGHTS AND JUST ENOUGH COOL AIR ALOFT TO MAKE IT DIFFICULT TO
COMPLETELY RULE OUT SHOWERS ANYTIME BETWEEN WED-FRI. 12Z GEM/EC SHOW
A COLD FRONT HOLDING TOGETHER ENOUGH TO BRING A MORE ORGANIZED CHANCE
OF SHOWERS TO OUR NORTHERN ZONES THU NIGHT/FRI. HOWEVER THE 12Z GFS
HAS THIS SYSTEM FALLING APART BEFORE MOVING ONSHORE. RAIN CHANCES
INCREASE NEXT WEEKEND AS MODELS AGREE ON A STRONGER FRONTAL SYSTEM
MOVING ONSHORE...PERHAPS WITH A WEAK TO MODEST ATMOSPHERIC RIVER.
CONFIDENCE IS HIGH ONE THING...AFTER THIS MONDAY THE NEAR- RECORD
WARMTH WILL BE HISTORY AND TEMPS WILL BE MUCH CLOSER TO LATE APRIL
NORMALS.  WEAGLE

&&

.AVIATION...CONTINUED VFR THROUGH 21/06Z...EXCEPT AT THE COAST
WHERE PATCHY FOG MAY AGAIN DEVELOP BETWEEN 10Z AND 15Z. EXPECT THE
COAST WILL RETURN TO VFR FOR THE BULK OF DAYLIGHT HOURS BUT AM
SEEING INDICATIONS FROM THE 12Z WRF ARW HIGH RESOLUTION MODEL OF
A FOG/STRATUS DECK REACHING THE COAST BETWEEN 21/00 AND 21/03Z.
WILL WAIT FOR THE 00Z RUN BEFORE COMMITTING TO THE TAF.

KPDX AND APPROACHES...CLEAR AND DRY UNDER HIGH PRES. NO WEATHER
IMPACTS EXPECTED THROUGH MON. /JBONK


&&

.MARINE...WINDS CONTINUE TO GRADUALLY DIMINISH TONIGHT AS THE
THERMALLY INDUCED PRESSURE GRADIENT WEAKENS. STILL EXPECT
NORTHERLY GUSTS 20 TO 25 KT THROUGH 5 AM MONDAY. WINDS WILL
SUBSIDE FURTHER DURING THE DAY MON AS A WEAK FRONT APPROACHES AND
SHUNTS THE UPPER RIDGE EAST ACROSS THE CASCADES.THE FRONT WILL MOVE
ACROSS ON TUE AND SHOULD NOT CAUSE MUCH IN THE WAY OF MARINE
CONCERNS. THE NE PAC HIGH STRENGTHENS AGAIN MID-WEEK SIGNALING A
RETURN OF THE COASTAL THERMAL SURFACE LOW. THEN EXPECT A RETURN OF
THE GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS FOR TUE NIGHT AND WED.
THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT MOVES ACROSS.

SEAS WILL REMAIN AROUND 7 FT THROUGH TUE. THE INCREASING WINDS
TUE NIGHT AND WED WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT
FOR A BRIEF PERIOD BEFORE THEY DROP BACK DOWN ON THU.

HAVE DECIDED TO DROP THE SMALL CRAFT ADVISORY FOR THE COLUMBIA
BAR COVERING THE EBB AROUND SUNRISE MON. CONDITIONS REPORTED BY
THE COAST GUARD HAVE BEEN SIGNIFICANTLY UNDER PERFORMING THE
LOCAL MODEL OUTPUT. JBONK

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 AM PDT MONDAY FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT
     60 NM.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KOTX 192329
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
429 PM PDT SUN APR 19 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and cooler temperatures. After this, a number of potential waves
track across the Inland Northwest. The heaviest amounts of rain
will fall across North Idaho, with snow levels high enough to not
pose a threat to any regional passes.

&&

.DISCUSSION...
Tonight through Tuesday...Satellite indicates dry northwest flow
aloft under the east flank of an approaching upper level ridge.
This will be the main driver of sensible weather for the next two
days...featuring mainly clear skies...light winds and increasingly
warm temperatures with widespread low to mid 70s by Tuesday
afternoon. There is not much else to elaborate on for this period.

Tuesday night through Wednesday night...This period will bring a
change to the dry and warm weather stretch. Models are in
agreement in dragging a moderate strength upper level trough
through the region beginning with a chance of showers or a stray
thunderstorms Tuesday evening/night over the high Cascades with a
general spreading out of this precipitation risk through the
basin on Wednesday and into the Idaho Panhandle Wednesday night.
This does not look like a significant precipitation maker with
fairly weak dynamic support and marginal deep moisture
availability and instability. The ECMWF model is the most
aggressive and fastest model which implies a better chance of
showers and isolated afternoon and evening thunderstorms...while
the GFS is slower and weaker. While confidence is growing that
Wednesday will feature at least more clouds and slightly cooler
temperatures with a few showers...confidence is low regarding
which model is more plausible at this time. /Fugazzi

Thursday through Sunday: A weak front will move through the area
early Thursday. By Thur afternoon the GFS is showing some decent
instability along the border btwn ID and MT. Have kept
thunderstorms in through the afternoon hours. But thereafter the
models are not in very good agreement about the rest of the work
week and next weekend. The 12Z ECMWF brings a large trough of low
pressure through the Pacific Northwest late Thur night through
early Sat morning. It then builds a shortwave ridge over the area
for Saturday and Sunday. Whereas the 12Z gfs brings several
fairly weak waves through broad southwest flow through Sunday.
Needless to say there is high uncertainty in the extended period.
Kept chance of precipitation around average for this time of the
year....meaning a slight chance in most valleys and a chance of
precip in the mountains. Thursday daytime highs should be a few
degrees above average. Then through the remainder of the forecast
period temps will be right around average for this time of the
year. /Nisbet

&&

.AVIATION...
00Z TAFS: High pressure building into the region will result in
VFR conditions through Monday afternoon. Winds will remain weak
and some passing high cirrus can be expected to drop south into
the region out of BC. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        42  72  45  75  50  70 /   0   0   0   0  10  20
Coeur d`Alene  37  70  41  75  44  70 /   0   0   0   0  10  30
Pullman        39  69  40  74  46  67 /   0   0   0   0  10  20
Lewiston       44  76  46  78  49  72 /   0   0   0   0  10  20
Colville       40  74  41  77  46  73 /   0   0   0   0  10  30
Sandpoint      35  69  37  73  40  71 /   0   0   0   0  10  30
Kellogg        37  68  39  74  43  70 /   0   0   0   0  10  40
Moses Lake     42  76  43  78  50  74 /   0   0   0   0  10  20
Wenatchee      48  76  50  77  53  72 /   0   0   0  10  10  20
Omak           42  76  43  77  47  73 /   0   0   0  10  10  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&




000
FXUS66 KOTX 192329
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
429 PM PDT SUN APR 19 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and cooler temperatures. After this, a number of potential waves
track across the Inland Northwest. The heaviest amounts of rain
will fall across North Idaho, with snow levels high enough to not
pose a threat to any regional passes.

&&

.DISCUSSION...
Tonight through Tuesday...Satellite indicates dry northwest flow
aloft under the east flank of an approaching upper level ridge.
This will be the main driver of sensible weather for the next two
days...featuring mainly clear skies...light winds and increasingly
warm temperatures with widespread low to mid 70s by Tuesday
afternoon. There is not much else to elaborate on for this period.

Tuesday night through Wednesday night...This period will bring a
change to the dry and warm weather stretch. Models are in
agreement in dragging a moderate strength upper level trough
through the region beginning with a chance of showers or a stray
thunderstorms Tuesday evening/night over the high Cascades with a
general spreading out of this precipitation risk through the
basin on Wednesday and into the Idaho Panhandle Wednesday night.
This does not look like a significant precipitation maker with
fairly weak dynamic support and marginal deep moisture
availability and instability. The ECMWF model is the most
aggressive and fastest model which implies a better chance of
showers and isolated afternoon and evening thunderstorms...while
the GFS is slower and weaker. While confidence is growing that
Wednesday will feature at least more clouds and slightly cooler
temperatures with a few showers...confidence is low regarding
which model is more plausible at this time. /Fugazzi

Thursday through Sunday: A weak front will move through the area
early Thursday. By Thur afternoon the GFS is showing some decent
instability along the border btwn ID and MT. Have kept
thunderstorms in through the afternoon hours. But thereafter the
models are not in very good agreement about the rest of the work
week and next weekend. The 12Z ECMWF brings a large trough of low
pressure through the Pacific Northwest late Thur night through
early Sat morning. It then builds a shortwave ridge over the area
for Saturday and Sunday. Whereas the 12Z gfs brings several
fairly weak waves through broad southwest flow through Sunday.
Needless to say there is high uncertainty in the extended period.
Kept chance of precipitation around average for this time of the
year....meaning a slight chance in most valleys and a chance of
precip in the mountains. Thursday daytime highs should be a few
degrees above average. Then through the remainder of the forecast
period temps will be right around average for this time of the
year. /Nisbet

&&

.AVIATION...
00Z TAFS: High pressure building into the region will result in
VFR conditions through Monday afternoon. Winds will remain weak
and some passing high cirrus can be expected to drop south into
the region out of BC. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        42  72  45  75  50  70 /   0   0   0   0  10  20
Coeur d`Alene  37  70  41  75  44  70 /   0   0   0   0  10  30
Pullman        39  69  40  74  46  67 /   0   0   0   0  10  20
Lewiston       44  76  46  78  49  72 /   0   0   0   0  10  20
Colville       40  74  41  77  46  73 /   0   0   0   0  10  30
Sandpoint      35  69  37  73  40  71 /   0   0   0   0  10  30
Kellogg        37  68  39  74  43  70 /   0   0   0   0  10  40
Moses Lake     42  76  43  78  50  74 /   0   0   0   0  10  20
Wenatchee      48  76  50  77  53  72 /   0   0   0  10  10  20
Omak           42  76  43  77  47  73 /   0   0   0  10  10  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&




000
FXUS66 KOTX 192329
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
429 PM PDT SUN APR 19 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and cooler temperatures. After this, a number of potential waves
track across the Inland Northwest. The heaviest amounts of rain
will fall across North Idaho, with snow levels high enough to not
pose a threat to any regional passes.

&&

.DISCUSSION...
Tonight through Tuesday...Satellite indicates dry northwest flow
aloft under the east flank of an approaching upper level ridge.
This will be the main driver of sensible weather for the next two
days...featuring mainly clear skies...light winds and increasingly
warm temperatures with widespread low to mid 70s by Tuesday
afternoon. There is not much else to elaborate on for this period.

Tuesday night through Wednesday night...This period will bring a
change to the dry and warm weather stretch. Models are in
agreement in dragging a moderate strength upper level trough
through the region beginning with a chance of showers or a stray
thunderstorms Tuesday evening/night over the high Cascades with a
general spreading out of this precipitation risk through the
basin on Wednesday and into the Idaho Panhandle Wednesday night.
This does not look like a significant precipitation maker with
fairly weak dynamic support and marginal deep moisture
availability and instability. The ECMWF model is the most
aggressive and fastest model which implies a better chance of
showers and isolated afternoon and evening thunderstorms...while
the GFS is slower and weaker. While confidence is growing that
Wednesday will feature at least more clouds and slightly cooler
temperatures with a few showers...confidence is low regarding
which model is more plausible at this time. /Fugazzi

Thursday through Sunday: A weak front will move through the area
early Thursday. By Thur afternoon the GFS is showing some decent
instability along the border btwn ID and MT. Have kept
thunderstorms in through the afternoon hours. But thereafter the
models are not in very good agreement about the rest of the work
week and next weekend. The 12Z ECMWF brings a large trough of low
pressure through the Pacific Northwest late Thur night through
early Sat morning. It then builds a shortwave ridge over the area
for Saturday and Sunday. Whereas the 12Z gfs brings several
fairly weak waves through broad southwest flow through Sunday.
Needless to say there is high uncertainty in the extended period.
Kept chance of precipitation around average for this time of the
year....meaning a slight chance in most valleys and a chance of
precip in the mountains. Thursday daytime highs should be a few
degrees above average. Then through the remainder of the forecast
period temps will be right around average for this time of the
year. /Nisbet

&&

.AVIATION...
00Z TAFS: High pressure building into the region will result in
VFR conditions through Monday afternoon. Winds will remain weak
and some passing high cirrus can be expected to drop south into
the region out of BC. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        42  72  45  75  50  70 /   0   0   0   0  10  20
Coeur d`Alene  37  70  41  75  44  70 /   0   0   0   0  10  30
Pullman        39  69  40  74  46  67 /   0   0   0   0  10  20
Lewiston       44  76  46  78  49  72 /   0   0   0   0  10  20
Colville       40  74  41  77  46  73 /   0   0   0   0  10  30
Sandpoint      35  69  37  73  40  71 /   0   0   0   0  10  30
Kellogg        37  68  39  74  43  70 /   0   0   0   0  10  40
Moses Lake     42  76  43  78  50  74 /   0   0   0   0  10  20
Wenatchee      48  76  50  77  53  72 /   0   0   0  10  10  20
Omak           42  76  43  77  47  73 /   0   0   0  10  10  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&




000
FXUS66 KOTX 192329
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
429 PM PDT SUN APR 19 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and cooler temperatures. After this, a number of potential waves
track across the Inland Northwest. The heaviest amounts of rain
will fall across North Idaho, with snow levels high enough to not
pose a threat to any regional passes.

&&

.DISCUSSION...
Tonight through Tuesday...Satellite indicates dry northwest flow
aloft under the east flank of an approaching upper level ridge.
This will be the main driver of sensible weather for the next two
days...featuring mainly clear skies...light winds and increasingly
warm temperatures with widespread low to mid 70s by Tuesday
afternoon. There is not much else to elaborate on for this period.

Tuesday night through Wednesday night...This period will bring a
change to the dry and warm weather stretch. Models are in
agreement in dragging a moderate strength upper level trough
through the region beginning with a chance of showers or a stray
thunderstorms Tuesday evening/night over the high Cascades with a
general spreading out of this precipitation risk through the
basin on Wednesday and into the Idaho Panhandle Wednesday night.
This does not look like a significant precipitation maker with
fairly weak dynamic support and marginal deep moisture
availability and instability. The ECMWF model is the most
aggressive and fastest model which implies a better chance of
showers and isolated afternoon and evening thunderstorms...while
the GFS is slower and weaker. While confidence is growing that
Wednesday will feature at least more clouds and slightly cooler
temperatures with a few showers...confidence is low regarding
which model is more plausible at this time. /Fugazzi

Thursday through Sunday: A weak front will move through the area
early Thursday. By Thur afternoon the GFS is showing some decent
instability along the border btwn ID and MT. Have kept
thunderstorms in through the afternoon hours. But thereafter the
models are not in very good agreement about the rest of the work
week and next weekend. The 12Z ECMWF brings a large trough of low
pressure through the Pacific Northwest late Thur night through
early Sat morning. It then builds a shortwave ridge over the area
for Saturday and Sunday. Whereas the 12Z gfs brings several
fairly weak waves through broad southwest flow through Sunday.
Needless to say there is high uncertainty in the extended period.
Kept chance of precipitation around average for this time of the
year....meaning a slight chance in most valleys and a chance of
precip in the mountains. Thursday daytime highs should be a few
degrees above average. Then through the remainder of the forecast
period temps will be right around average for this time of the
year. /Nisbet

&&

.AVIATION...
00Z TAFS: High pressure building into the region will result in
VFR conditions through Monday afternoon. Winds will remain weak
and some passing high cirrus can be expected to drop south into
the region out of BC. /SVH

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        42  72  45  75  50  70 /   0   0   0   0  10  20
Coeur d`Alene  37  70  41  75  44  70 /   0   0   0   0  10  30
Pullman        39  69  40  74  46  67 /   0   0   0   0  10  20
Lewiston       44  76  46  78  49  72 /   0   0   0   0  10  20
Colville       40  74  41  77  46  73 /   0   0   0   0  10  30
Sandpoint      35  69  37  73  40  71 /   0   0   0   0  10  30
Kellogg        37  68  39  74  43  70 /   0   0   0   0  10  40
Moses Lake     42  76  43  78  50  74 /   0   0   0   0  10  20
Wenatchee      48  76  50  77  53  72 /   0   0   0  10  10  20
Omak           42  76  43  77  47  73 /   0   0   0  10  10  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&




000
FXUS66 KSEW 192234 CCA
AFDSEW

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SEATTLE WA
334 PM PDT SUN APR 19 2015

CORRECTED MINOR TYPO IN THE SYNOPSIS.

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
THE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...
A GRADUALLY WEAKENING UPPER RIDGE OVER THE PACIFIC NORTHWEST WILL
MOVE OVER THE INTERMOUNTAIN WEST ON TUE. THIS WILL ALLOW AN UPPER
TROF OVER THE NORTHEAST PACIFIC TO APPROACH THE REGION. THIS...IN
TURN...WILL SERVE TO INITIATE A MARINE PUSH. IT LOOKS LIKE THE
PUSH WILL BEGIN MON AFTERNOON BUT WILL STRENGTHEN ON TUE.
CONSEQUENTLY...ANTICIPATE COOLER AND CLOUDIER CONDITIONS ON TUE.
WHAT IS LEFT OF A COLD FRONT WILL MOVE ACROSS THE CWA TUE
AFTERNOON FOR A THREAT OF SHOWERS. IT LOOKS LIKE THE RISK OF TSTMS
WILL STAY EAST OF THE CASCADES...SO THE POSSIBILITY WAS REMOVED
FROM THE FORECAST.

CONCERNING MAX TEMPS FOR MON AND TUE...CONFIDENCE IN THE FORECAST
FOR MON WAS NOT VERY HIGH. THE WEAKENING UPPER RIDGE COMBINED WITH
INCREASED LOW LEVEL ONSHORE FLOW WOULD SUPPORT TEMPS BEING CLOSER
TO THE ECMWF MOS GUIDANCE. SINCE THE ECMWF TENDS TO HANDLE SPLIT
FLOW REGIMES BETTER...DECIDED TO LEAN TOWARD THIS MODEL. WITH THAT
SAID...TUE SHOULD BE NOTICEABLY COOLER ACROSS MUCH OF THE CWA.
THE NAM AND GFS APPEARED TOO WARM...ESPECIALLY WHEN FACTORING IN
THE STRENGTH OF THE ONSHORE PRESSURE GRADIENT. THUS...LEANED
TOWARD THE ECMWF GUIDANCE. ALTHOUGH...THERE IS A CHANCE THAT THE
FORECAST MAX TEMPS FOR TUE COULD BE 3-5 DEGREES TOO WARM.

THE ECMWF INDICATED THAT THE TROF IN THE NORTHERN BRANCH WILL
APPROACH THE AREA TUE NIGHT AND THEN MOVE ACROSS THE CWA ON WED.
CONDITIONS SHOULD BE COOL AND A BIT ON THE CLOUDY SIDE. THERE WILL
ALSO BE A THREAT OF SHOWERS. MAX TEMPS ACROSS MOST LOWLAND LOCALES
ON WED SHOULD ONLY BE IN THE MID TO UPPER 50S.

.LONG TERM...
THE EXTENDED PERIOD STILL APPEARED COOL AND UNSETTLED...HOWEVER
CONFIDENCE IN THE DETAILS WERE NOT HIGH DUE TO LACK OF CONSISTENCY
AND AGREEMENT IN THE MEDIUM RANGE SOLUTIONS. ANTICIPATE NEAR OR
SLIGHTLY BELOW NORMAL DAYTIME TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE IS OVER THE PACNW. FAIR SKIES WITH
A DRY STABLE AIR MASS WILL REMAIN IN PLACE. THE FLOW ALOFT IS NW
WITH JUST A LITTLE CIRRUS.

KSEA...A LITTLE CIRRUS...NORTHERLY BREEZE.

&&

.MARINE...THERMALLY INDUCED LOW PRESSURE OVER CALIF EXTENDS NORTH
ALONG THE COAST. ONSHORE FLOW SHOULD DEVELOP MONDAY EVENING AND THEN
INCREASE TUESDAY AS A FRONT REACHES THE AREA. ONSHORE FLOW WILL
CONTINUE THROUGH THE END OF THE WEEK.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML






000
FXUS66 KSEW 192234 CCA
AFDSEW

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SEATTLE WA
334 PM PDT SUN APR 19 2015

CORRECTED MINOR TYPO IN THE SYNOPSIS.

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
THE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...
A GRADUALLY WEAKENING UPPER RIDGE OVER THE PACIFIC NORTHWEST WILL
MOVE OVER THE INTERMOUNTAIN WEST ON TUE. THIS WILL ALLOW AN UPPER
TROF OVER THE NORTHEAST PACIFIC TO APPROACH THE REGION. THIS...IN
TURN...WILL SERVE TO INITIATE A MARINE PUSH. IT LOOKS LIKE THE
PUSH WILL BEGIN MON AFTERNOON BUT WILL STRENGTHEN ON TUE.
CONSEQUENTLY...ANTICIPATE COOLER AND CLOUDIER CONDITIONS ON TUE.
WHAT IS LEFT OF A COLD FRONT WILL MOVE ACROSS THE CWA TUE
AFTERNOON FOR A THREAT OF SHOWERS. IT LOOKS LIKE THE RISK OF TSTMS
WILL STAY EAST OF THE CASCADES...SO THE POSSIBILITY WAS REMOVED
FROM THE FORECAST.

CONCERNING MAX TEMPS FOR MON AND TUE...CONFIDENCE IN THE FORECAST
FOR MON WAS NOT VERY HIGH. THE WEAKENING UPPER RIDGE COMBINED WITH
INCREASED LOW LEVEL ONSHORE FLOW WOULD SUPPORT TEMPS BEING CLOSER
TO THE ECMWF MOS GUIDANCE. SINCE THE ECMWF TENDS TO HANDLE SPLIT
FLOW REGIMES BETTER...DECIDED TO LEAN TOWARD THIS MODEL. WITH THAT
SAID...TUE SHOULD BE NOTICEABLY COOLER ACROSS MUCH OF THE CWA.
THE NAM AND GFS APPEARED TOO WARM...ESPECIALLY WHEN FACTORING IN
THE STRENGTH OF THE ONSHORE PRESSURE GRADIENT. THUS...LEANED
TOWARD THE ECMWF GUIDANCE. ALTHOUGH...THERE IS A CHANCE THAT THE
FORECAST MAX TEMPS FOR TUE COULD BE 3-5 DEGREES TOO WARM.

THE ECMWF INDICATED THAT THE TROF IN THE NORTHERN BRANCH WILL
APPROACH THE AREA TUE NIGHT AND THEN MOVE ACROSS THE CWA ON WED.
CONDITIONS SHOULD BE COOL AND A BIT ON THE CLOUDY SIDE. THERE WILL
ALSO BE A THREAT OF SHOWERS. MAX TEMPS ACROSS MOST LOWLAND LOCALES
ON WED SHOULD ONLY BE IN THE MID TO UPPER 50S.

.LONG TERM...
THE EXTENDED PERIOD STILL APPEARED COOL AND UNSETTLED...HOWEVER
CONFIDENCE IN THE DETAILS WERE NOT HIGH DUE TO LACK OF CONSISTENCY
AND AGREEMENT IN THE MEDIUM RANGE SOLUTIONS. ANTICIPATE NEAR OR
SLIGHTLY BELOW NORMAL DAYTIME TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE IS OVER THE PACNW. FAIR SKIES WITH
A DRY STABLE AIR MASS WILL REMAIN IN PLACE. THE FLOW ALOFT IS NW
WITH JUST A LITTLE CIRRUS.

KSEA...A LITTLE CIRRUS...NORTHERLY BREEZE.

&&

.MARINE...THERMALLY INDUCED LOW PRESSURE OVER CALIF EXTENDS NORTH
ALONG THE COAST. ONSHORE FLOW SHOULD DEVELOP MONDAY EVENING AND THEN
INCREASE TUESDAY AS A FRONT REACHES THE AREA. ONSHORE FLOW WILL
CONTINUE THROUGH THE END OF THE WEEK.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML






000
FXUS66 KSEW 192234 CCA
AFDSEW

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SEATTLE WA
334 PM PDT SUN APR 19 2015

CORRECTED MINOR TYPO IN THE SYNOPSIS.

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
THE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...
A GRADUALLY WEAKENING UPPER RIDGE OVER THE PACIFIC NORTHWEST WILL
MOVE OVER THE INTERMOUNTAIN WEST ON TUE. THIS WILL ALLOW AN UPPER
TROF OVER THE NORTHEAST PACIFIC TO APPROACH THE REGION. THIS...IN
TURN...WILL SERVE TO INITIATE A MARINE PUSH. IT LOOKS LIKE THE
PUSH WILL BEGIN MON AFTERNOON BUT WILL STRENGTHEN ON TUE.
CONSEQUENTLY...ANTICIPATE COOLER AND CLOUDIER CONDITIONS ON TUE.
WHAT IS LEFT OF A COLD FRONT WILL MOVE ACROSS THE CWA TUE
AFTERNOON FOR A THREAT OF SHOWERS. IT LOOKS LIKE THE RISK OF TSTMS
WILL STAY EAST OF THE CASCADES...SO THE POSSIBILITY WAS REMOVED
FROM THE FORECAST.

CONCERNING MAX TEMPS FOR MON AND TUE...CONFIDENCE IN THE FORECAST
FOR MON WAS NOT VERY HIGH. THE WEAKENING UPPER RIDGE COMBINED WITH
INCREASED LOW LEVEL ONSHORE FLOW WOULD SUPPORT TEMPS BEING CLOSER
TO THE ECMWF MOS GUIDANCE. SINCE THE ECMWF TENDS TO HANDLE SPLIT
FLOW REGIMES BETTER...DECIDED TO LEAN TOWARD THIS MODEL. WITH THAT
SAID...TUE SHOULD BE NOTICEABLY COOLER ACROSS MUCH OF THE CWA.
THE NAM AND GFS APPEARED TOO WARM...ESPECIALLY WHEN FACTORING IN
THE STRENGTH OF THE ONSHORE PRESSURE GRADIENT. THUS...LEANED
TOWARD THE ECMWF GUIDANCE. ALTHOUGH...THERE IS A CHANCE THAT THE
FORECAST MAX TEMPS FOR TUE COULD BE 3-5 DEGREES TOO WARM.

THE ECMWF INDICATED THAT THE TROF IN THE NORTHERN BRANCH WILL
APPROACH THE AREA TUE NIGHT AND THEN MOVE ACROSS THE CWA ON WED.
CONDITIONS SHOULD BE COOL AND A BIT ON THE CLOUDY SIDE. THERE WILL
ALSO BE A THREAT OF SHOWERS. MAX TEMPS ACROSS MOST LOWLAND LOCALES
ON WED SHOULD ONLY BE IN THE MID TO UPPER 50S.

.LONG TERM...
THE EXTENDED PERIOD STILL APPEARED COOL AND UNSETTLED...HOWEVER
CONFIDENCE IN THE DETAILS WERE NOT HIGH DUE TO LACK OF CONSISTENCY
AND AGREEMENT IN THE MEDIUM RANGE SOLUTIONS. ANTICIPATE NEAR OR
SLIGHTLY BELOW NORMAL DAYTIME TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE IS OVER THE PACNW. FAIR SKIES WITH
A DRY STABLE AIR MASS WILL REMAIN IN PLACE. THE FLOW ALOFT IS NW
WITH JUST A LITTLE CIRRUS.

KSEA...A LITTLE CIRRUS...NORTHERLY BREEZE.

&&

.MARINE...THERMALLY INDUCED LOW PRESSURE OVER CALIF EXTENDS NORTH
ALONG THE COAST. ONSHORE FLOW SHOULD DEVELOP MONDAY EVENING AND THEN
INCREASE TUESDAY AS A FRONT REACHES THE AREA. ONSHORE FLOW WILL
CONTINUE THROUGH THE END OF THE WEEK.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML






000
FXUS66 KSEW 192234 CCA
AFDSEW

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SEATTLE WA
334 PM PDT SUN APR 19 2015

CORRECTED MINOR TYPO IN THE SYNOPSIS.

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
THE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...
A GRADUALLY WEAKENING UPPER RIDGE OVER THE PACIFIC NORTHWEST WILL
MOVE OVER THE INTERMOUNTAIN WEST ON TUE. THIS WILL ALLOW AN UPPER
TROF OVER THE NORTHEAST PACIFIC TO APPROACH THE REGION. THIS...IN
TURN...WILL SERVE TO INITIATE A MARINE PUSH. IT LOOKS LIKE THE
PUSH WILL BEGIN MON AFTERNOON BUT WILL STRENGTHEN ON TUE.
CONSEQUENTLY...ANTICIPATE COOLER AND CLOUDIER CONDITIONS ON TUE.
WHAT IS LEFT OF A COLD FRONT WILL MOVE ACROSS THE CWA TUE
AFTERNOON FOR A THREAT OF SHOWERS. IT LOOKS LIKE THE RISK OF TSTMS
WILL STAY EAST OF THE CASCADES...SO THE POSSIBILITY WAS REMOVED
FROM THE FORECAST.

CONCERNING MAX TEMPS FOR MON AND TUE...CONFIDENCE IN THE FORECAST
FOR MON WAS NOT VERY HIGH. THE WEAKENING UPPER RIDGE COMBINED WITH
INCREASED LOW LEVEL ONSHORE FLOW WOULD SUPPORT TEMPS BEING CLOSER
TO THE ECMWF MOS GUIDANCE. SINCE THE ECMWF TENDS TO HANDLE SPLIT
FLOW REGIMES BETTER...DECIDED TO LEAN TOWARD THIS MODEL. WITH THAT
SAID...TUE SHOULD BE NOTICEABLY COOLER ACROSS MUCH OF THE CWA.
THE NAM AND GFS APPEARED TOO WARM...ESPECIALLY WHEN FACTORING IN
THE STRENGTH OF THE ONSHORE PRESSURE GRADIENT. THUS...LEANED
TOWARD THE ECMWF GUIDANCE. ALTHOUGH...THERE IS A CHANCE THAT THE
FORECAST MAX TEMPS FOR TUE COULD BE 3-5 DEGREES TOO WARM.

THE ECMWF INDICATED THAT THE TROF IN THE NORTHERN BRANCH WILL
APPROACH THE AREA TUE NIGHT AND THEN MOVE ACROSS THE CWA ON WED.
CONDITIONS SHOULD BE COOL AND A BIT ON THE CLOUDY SIDE. THERE WILL
ALSO BE A THREAT OF SHOWERS. MAX TEMPS ACROSS MOST LOWLAND LOCALES
ON WED SHOULD ONLY BE IN THE MID TO UPPER 50S.

.LONG TERM...
THE EXTENDED PERIOD STILL APPEARED COOL AND UNSETTLED...HOWEVER
CONFIDENCE IN THE DETAILS WERE NOT HIGH DUE TO LACK OF CONSISTENCY
AND AGREEMENT IN THE MEDIUM RANGE SOLUTIONS. ANTICIPATE NEAR OR
SLIGHTLY BELOW NORMAL DAYTIME TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE IS OVER THE PACNW. FAIR SKIES WITH
A DRY STABLE AIR MASS WILL REMAIN IN PLACE. THE FLOW ALOFT IS NW
WITH JUST A LITTLE CIRRUS.

KSEA...A LITTLE CIRRUS...NORTHERLY BREEZE.

&&

.MARINE...THERMALLY INDUCED LOW PRESSURE OVER CALIF EXTENDS NORTH
ALONG THE COAST. ONSHORE FLOW SHOULD DEVELOP MONDAY EVENING AND THEN
INCREASE TUESDAY AS A FRONT REACHES THE AREA. ONSHORE FLOW WILL
CONTINUE THROUGH THE END OF THE WEEK.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML






000
FXUS66 KSEW 192234 CCA
AFDSEW

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SEATTLE WA
334 PM PDT SUN APR 19 2015

CORRECTED MINOR TYPO IN THE SYNOPSIS.

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
THE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...
A GRADUALLY WEAKENING UPPER RIDGE OVER THE PACIFIC NORTHWEST WILL
MOVE OVER THE INTERMOUNTAIN WEST ON TUE. THIS WILL ALLOW AN UPPER
TROF OVER THE NORTHEAST PACIFIC TO APPROACH THE REGION. THIS...IN
TURN...WILL SERVE TO INITIATE A MARINE PUSH. IT LOOKS LIKE THE
PUSH WILL BEGIN MON AFTERNOON BUT WILL STRENGTHEN ON TUE.
CONSEQUENTLY...ANTICIPATE COOLER AND CLOUDIER CONDITIONS ON TUE.
WHAT IS LEFT OF A COLD FRONT WILL MOVE ACROSS THE CWA TUE
AFTERNOON FOR A THREAT OF SHOWERS. IT LOOKS LIKE THE RISK OF TSTMS
WILL STAY EAST OF THE CASCADES...SO THE POSSIBILITY WAS REMOVED
FROM THE FORECAST.

CONCERNING MAX TEMPS FOR MON AND TUE...CONFIDENCE IN THE FORECAST
FOR MON WAS NOT VERY HIGH. THE WEAKENING UPPER RIDGE COMBINED WITH
INCREASED LOW LEVEL ONSHORE FLOW WOULD SUPPORT TEMPS BEING CLOSER
TO THE ECMWF MOS GUIDANCE. SINCE THE ECMWF TENDS TO HANDLE SPLIT
FLOW REGIMES BETTER...DECIDED TO LEAN TOWARD THIS MODEL. WITH THAT
SAID...TUE SHOULD BE NOTICEABLY COOLER ACROSS MUCH OF THE CWA.
THE NAM AND GFS APPEARED TOO WARM...ESPECIALLY WHEN FACTORING IN
THE STRENGTH OF THE ONSHORE PRESSURE GRADIENT. THUS...LEANED
TOWARD THE ECMWF GUIDANCE. ALTHOUGH...THERE IS A CHANCE THAT THE
FORECAST MAX TEMPS FOR TUE COULD BE 3-5 DEGREES TOO WARM.

THE ECMWF INDICATED THAT THE TROF IN THE NORTHERN BRANCH WILL
APPROACH THE AREA TUE NIGHT AND THEN MOVE ACROSS THE CWA ON WED.
CONDITIONS SHOULD BE COOL AND A BIT ON THE CLOUDY SIDE. THERE WILL
ALSO BE A THREAT OF SHOWERS. MAX TEMPS ACROSS MOST LOWLAND LOCALES
ON WED SHOULD ONLY BE IN THE MID TO UPPER 50S.

.LONG TERM...
THE EXTENDED PERIOD STILL APPEARED COOL AND UNSETTLED...HOWEVER
CONFIDENCE IN THE DETAILS WERE NOT HIGH DUE TO LACK OF CONSISTENCY
AND AGREEMENT IN THE MEDIUM RANGE SOLUTIONS. ANTICIPATE NEAR OR
SLIGHTLY BELOW NORMAL DAYTIME TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE IS OVER THE PACNW. FAIR SKIES WITH
A DRY STABLE AIR MASS WILL REMAIN IN PLACE. THE FLOW ALOFT IS NW
WITH JUST A LITTLE CIRRUS.

KSEA...A LITTLE CIRRUS...NORTHERLY BREEZE.

&&

.MARINE...THERMALLY INDUCED LOW PRESSURE OVER CALIF EXTENDS NORTH
ALONG THE COAST. ONSHORE FLOW SHOULD DEVELOP MONDAY EVENING AND THEN
INCREASE TUESDAY AS A FRONT REACHES THE AREA. ONSHORE FLOW WILL
CONTINUE THROUGH THE END OF THE WEEK.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML





000
FXUS66 KSEW 192225
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
325 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
HE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...
A GRADUALLY WEAKENING UPPER RIDGE OVER THE PACIFIC NORTHWEST WILL
MOVE OVER THE INTERMOUNTAIN WEST ON TUE. THIS WILL ALLOW AN UPPER
TROF OVER THE NORTHEAST PACIFIC TO APPROACH THE REGION. THIS...IN
TURN...WILL SERVE TO INITIATE A MARINE PUSH. IT LOOKS LIKE THE
PUSH WILL BEGIN MON AFTERNOON BUT WILL STRENGTHEN ON TUE.
CONSEQUENTLY...ANTICIPATE COOLER AND CLOUDIER CONDITIONS ON TUE.
WHAT IS LEFT OF A COLD FRONT WILL MOVE ACROSS THE CWA TUE
AFTERNOON FOR A THREAT OF SHOWERS. IT LOOKS LIKE THE RISK OF TSTMS
WILL STAY EAST OF THE CASCADES...SO THE POSSIBILITY WAS REMOVED
FROM THE FORECAST.

CONCERNING MAX TEMPS FOR MON AND TUE...CONFIDENCE IN THE FORECAST
FOR MON WAS NOT VERY HIGH. THE WEAKENING UPPER RIDGE COMBINED WITH
INCREASED LOW LEVEL ONSHORE FLOW WOULD SUPPORT TEMPS BEING CLOSER
TO THE ECMWF MOS GUIDANCE. SINCE THE ECMWF TENDS TO HANDLE SPLIT
FLOW REGIMES BETTER...DECIDED TO LEAN TOWARD THIS MODEL. WITH THAT
SAID...TUE SHOULD BE NOTICEABLY COOLER ACROSS MUCH OF THE CWA.
THE NAM AND GFS APPEARED TOO WARM...ESPECIALLY WHEN FACTORING IN
THE STRENGTH OF THE ONSHORE PRESSURE GRADIENT. THUS...LEANED
TOWARD THE ECMWF GUIDANCE. ALTHOUGH...THERE IS A CHANCE THAT THE
FORECAST MAX TEMPS FOR TUE COULD BE 3-5 DEGREES TOO WARM.

THE ECMWF INDICATED THAT THE TROF IN THE NORTHERN BRANCH WILL
APPROACH THE AREA TUE NIGHT AND THEN MOVE ACROSS THE CWA ON WED.
CONDITIONS SHOULD BE COOL AND A BIT ON THE CLOUDY SIDE. THERE WILL
ALSO BE A THREAT OF SHOWERS. MAX TEMPS ACROSS MOST LOWLAND LOCALES
ON WED SHOULD ONLY BE IN THE MID TO UPPER 50S.

.LONG TERM...
THE EXTENDED PERIOD STILL APPEARED COOL AND UNSETTLED...HOWEVER
CONFIDENCE IN THE DETAILS WERE NOT HIGH DUE TO LACK OF CONSISTENCY
AND AGREEMENT IN THE MEDIUM RANGE SOLUTIONS. ANTICIPATE NEAR OR
SLIGHTLY BELOW NORMAL DAYTIME TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE IS OVER THE PACNW. FAIR SKIES WITH
A DRY STABLE AIR MASS WILL REMAIN IN PLACE. THE FLOW ALOFT IS NW
WITH JUST A LITTLE CIRRUS.

KSEA...A LITTLE CIRRUS...NORTHERLY BREEZE.

&&

.MARINE...THERMALLY INDUCED LOW PRESSURE OVER CALIF EXTENDS NORTH
ALONG THE COAST. ONSHORE FLOW SHOULD DEVELOP MONDAY EVENING AND THEN
INCREASE TUESDAY AS A FRONT REACHES THE AREA. ONSHORE FLOW WILL
CONTINUE THROUGH THE END OF THE WEEK.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML





000
FXUS66 KSEW 192225
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
325 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PREVAIL OVER THE PACIFIC
NORTHWEST THROUGH MONDAY. THE HIGH WILL MOVE EAST OF THE REGION ON
TUESDAY AND THIS WILL ALLOW A LOW PRESSURE SYSTEM TO APPROACH FROM
THE PACIFIC. LOOK FOR WHAT IS LEFT OF THE COLD FRONT TO MOVE ACROSS
HE AREA TUESDAY AFTERNOON. THE LOW PRESSURE SYSTEM ALOFT WILL MOVE
ACROSS THE REGION ON WEDNESDAY.

&&

.SHORT TERM...
A GRADUALLY WEAKENING UPPER RIDGE OVER THE PACIFIC NORTHWEST WILL
MOVE OVER THE INTERMOUNTAIN WEST ON TUE. THIS WILL ALLOW AN UPPER
TROF OVER THE NORTHEAST PACIFIC TO APPROACH THE REGION. THIS...IN
TURN...WILL SERVE TO INITIATE A MARINE PUSH. IT LOOKS LIKE THE
PUSH WILL BEGIN MON AFTERNOON BUT WILL STRENGTHEN ON TUE.
CONSEQUENTLY...ANTICIPATE COOLER AND CLOUDIER CONDITIONS ON TUE.
WHAT IS LEFT OF A COLD FRONT WILL MOVE ACROSS THE CWA TUE
AFTERNOON FOR A THREAT OF SHOWERS. IT LOOKS LIKE THE RISK OF TSTMS
WILL STAY EAST OF THE CASCADES...SO THE POSSIBILITY WAS REMOVED
FROM THE FORECAST.

CONCERNING MAX TEMPS FOR MON AND TUE...CONFIDENCE IN THE FORECAST
FOR MON WAS NOT VERY HIGH. THE WEAKENING UPPER RIDGE COMBINED WITH
INCREASED LOW LEVEL ONSHORE FLOW WOULD SUPPORT TEMPS BEING CLOSER
TO THE ECMWF MOS GUIDANCE. SINCE THE ECMWF TENDS TO HANDLE SPLIT
FLOW REGIMES BETTER...DECIDED TO LEAN TOWARD THIS MODEL. WITH THAT
SAID...TUE SHOULD BE NOTICEABLY COOLER ACROSS MUCH OF THE CWA.
THE NAM AND GFS APPEARED TOO WARM...ESPECIALLY WHEN FACTORING IN
THE STRENGTH OF THE ONSHORE PRESSURE GRADIENT. THUS...LEANED
TOWARD THE ECMWF GUIDANCE. ALTHOUGH...THERE IS A CHANCE THAT THE
FORECAST MAX TEMPS FOR TUE COULD BE 3-5 DEGREES TOO WARM.

THE ECMWF INDICATED THAT THE TROF IN THE NORTHERN BRANCH WILL
APPROACH THE AREA TUE NIGHT AND THEN MOVE ACROSS THE CWA ON WED.
CONDITIONS SHOULD BE COOL AND A BIT ON THE CLOUDY SIDE. THERE WILL
ALSO BE A THREAT OF SHOWERS. MAX TEMPS ACROSS MOST LOWLAND LOCALES
ON WED SHOULD ONLY BE IN THE MID TO UPPER 50S.

.LONG TERM...
THE EXTENDED PERIOD STILL APPEARED COOL AND UNSETTLED...HOWEVER
CONFIDENCE IN THE DETAILS WERE NOT HIGH DUE TO LACK OF CONSISTENCY
AND AGREEMENT IN THE MEDIUM RANGE SOLUTIONS. ANTICIPATE NEAR OR
SLIGHTLY BELOW NORMAL DAYTIME TEMPS DURING THIS PERIOD.

&&

.AVIATION...AN UPPER LEVEL RIDGE IS OVER THE PACNW. FAIR SKIES WITH
A DRY STABLE AIR MASS WILL REMAIN IN PLACE. THE FLOW ALOFT IS NW
WITH JUST A LITTLE CIRRUS.

KSEA...A LITTLE CIRRUS...NORTHERLY BREEZE.

&&

.MARINE...THERMALLY INDUCED LOW PRESSURE OVER CALIF EXTENDS NORTH
ALONG THE COAST. ONSHORE FLOW SHOULD DEVELOP MONDAY EVENING AND THEN
INCREASE TUESDAY AS A FRONT REACHES THE AREA. ONSHORE FLOW WILL
CONTINUE THROUGH THE END OF THE WEEK.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML




000
FXUS66 KPQR 192157
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
257 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE CONTINUES TO PROVIDE UNSEASONABLY WARM AND
SUNNY WEATHER TO THE PACIFIC NORTHWEST TODAY...WITH MONDAY EXPECTED
TO BE VERY SIMILAR INLAND. THERMAL LOW PRESSURE WILL SHIFT INLAND
MONDAY...ALLOWING A DEEPER MARINE LAYER TO DEVELOP ALONG THE COAST BY
LATE AFTERNOON. THIS WILL BEGIN A SIGNIFICANT COOLDOWN FOR TUESDAY AS
A DEEP MARINE LAYER PUSHES ONSHORE AHEAD OF AN INCOMING COLD FRONT.
AN UPPER LEVEL TROUGH WILL THEN LINGER THROUGH THE END OF THE
WEEK...KEEPING TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL WITH A
CHANCE OF SHOWERS AT TIMES.

&&

.SHORT TERM...TONIGHT THROUGH WEDNESDAY...VISIBLE SATELLITE IMAGERY
SHOWS CLEAR SKIES YET AGAIN...EXCEPT FOR SOME SLIGHT FILTERING OF THE
SUNSHINE BY SMOKE FROM FIRES IN SOUTHERN SIBERIA LAST WEEK. AS
EXPECTED...IT IS APPEARING THAT SMOKE IS HAVING LITTLE TO NO IMPACT
ON TEMPERATURES TODAY. AS THE SUN ANGLE INCREASED...THE LOSS OF
INSOLATION AS DETECTED BY RAWS STATIONS DECREASED FROM 20-30 PERCENT
LOSS THIS MORNING TO ONLY A 5-10 PERCENT LOSS THIS AFTERNOON. AS A
RESULT TEMPS ARE GENERALLY 0-3 DEG F WARMER THAN THEY WERE YESTERDAY
AT THIS TIME...AND A COUPLE 80 DEGREE READINGS STILL LOOK POSSIBLE
FOR THE INLAND VALLEYS. IF NOT...THERE WILL BE PLENTY OF UPPER 70S.

FOG AND LOW CLOUDS WILL BE MINIMAL AGAIN TONIGHT THOUGH A PATCH OF
COASTAL STRATUS IS DEVELOPING ALONG THE WA COAST. THIS MAY SPREAD
SOME FOG INTO ASTORIA LATER TONIGHT...AND SOME PATCHY RADIATIONAL FOG
MAY DEVELOP AGAIN IN THE NEHALEM RIVER VALLEY AS WELL AS SOME OF THE
COASTAL VALLEYS.

NESDIS ANALYSTS BELIEVE THE SMOKE WILL BE LESS APPARENT MONDAY...
STAYING TO OUR NORTH AS THE UPPER RIDGE AXIS MOVES INTO THE PAC NW.
THEREFORE EXPECT PLENTY OF SUNSHINE AGAIN MONDAY FOR THE INLAND
AREAS. MODELS SHOW 500 MB HEIGHTS DECREASING A BIT MONDAY...BUT TEMPS
REMAIN ABOUT THE SAME AT 850 MB. WITH THE THERMAL TROUGH
OVERHEAD...PLENTY OF SUNSHINE...AND EVEN A LITTLE DOWNSLOPING OFF THE
COAST RANGE AS THE BEGINNINGS OF A SEABREEZE DEVELOP...EXPECT TEMPS
WILL REACH THE LOWER 80S FOR MANY INLAND SITES MONDAY. TEMPS IN
CORVALLIS AND EUGENE MAY BE CAPPED IN THE MID-UPPER 70S AS ONSHORE
FLOW BEGINS TO PUSH THROUGH THE COASTAL VALLEYS BY LATE AFTERNOON.

LOW CLOUDS SHOULD BEGIN DEVELOPING ALONG THE COAST BY LATE MONDAY
AFTERNOON...THEN PUSH INLAND OVERNIGHT MON NIGHT AHEAD OF AN INCOMING
UPPER TROUGH AND ASSOCIATED COLD FRONT. NAM CROSS SECTIONS SHOW A
DEEP MARINE LAYER PUSHING IN MONDAY NIGHT AND EARLY TUE... WITH THE
POTENTIAL FOR ISOLATED SHOWERS TUE AFTERNOON AS THE MARINE LAYER
MIXES/TURNS OVER. TEMPS WILL BE 10-15 DEGREES COOLER TUESDAY DUE TO
THE DEEP ONSHORE FLOW AND MARINE INFLUENCE. THE DEEP MARINE LAYER
WILL KEEP ANY SHOWERS SHALLOW EXCEPT ALONG THE CASCADE CREST WHICH
MAY REMAIN ABOVE THE MARINE INVERSION...WHERE SOME WARMER SURFACE
PARCELS MAY BE MORE BUOYANT FOR DEEPER SHOWERS AND ISOLATED
THUNDERSTORMS. A SIMILAR SITUATION IS EXPECTED WEDNESDAY...WITH A
DEEP MARINE LAYER...BUT PERHAPS A LITTLE MORE OF A TRIGGER FOR
SHOWERS AS THE UPPER TROUGH AXIS DRAGS ACROSS THE PAC NW. ONCE TEMPS
COOL DOWN TUESDAY...EXPECT NEAR TO SLIGHTLY BELOW NORMAL TEMPS TO
PERSIST FOR SEVERAL DAYS.  WEAGLE

.LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY...MODELS ARE HAVING A
HARD TIME WITH THE DETAILS OF WHAT IS LEFT BEHIND AS THE INCOMING
UPPER TROUGH FALLS APART OVER THE PACIFIC NORTHWEST MIDDLE TO LATE
THIS UPCOMING WEEK. IT APPEARS THERE WILL BE ENOUGH OF A WEAKNESS IN
500 MB HEIGHTS AND JUST ENOUGH COOL AIR ALOFT TO MAKE IT DIFFICULT TO
COMPLETELY RULE OUT SHOWERS ANYTIME BETWEEN WED-FRI. 12Z GEM/EC SHOW
A COLD FRONT HOLDING TOGETHER ENOUGH TO BRING A MORE ORGANIZED CHANCE
OF SHOWERS TO OUR NORTHERN ZONES THU NIGHT/FRI. HOWEVER THE 12Z GFS
HAS THIS SYSTEM FALLING APART BEFORE MOVING ONSHORE. RAIN CHANCES
INCREASE NEXT WEEKEND AS MODELS AGREE ON A STRONGER FRONTAL SYSTEM
MOVING ONSHORE...PERHAPS WITH A WEAK TO MODEST ATMOSPHERIC RIVER.
CONFIDENCE IS HIGH ONE THING...AFTER THIS MONDAY THE NEAR- RECORD
WARMTH WILL BE HISTORY AND TEMPS WILL BE MUCH CLOSER TO LATE APRIL
NORMALS.  WEAGLE

&&

.AVIATION...WIDESPREAD VFR CONDITIONS TO CONTINUE TODAY AND
TONIGHT WITH DRY NORTHERLY FLOW. BREEZY WINDS ALONG THE COAST WILL
CONTINUE INTO THIS EVENING...BUT WILL THEN SUBSIDE OVERNIGHT.
PATCHY FOG MAY AGAIN AFFECT THE COASTAL TAF SITES BETWEEN 10Z AND
15Z MON.

KPDX AND APPROACHES...CLEAR AND DRY UNDER HIGH PRES. NO WEATHER
IMPACTS EXPECTED THROUGH MON. BREEZY NW FLOW THROUGH THE AFTERNOON
AND EVENING WILL SUBSIDE OVERNIGHT. PYLE


&&

.MARINE...GUSTY 20 TO 25 KT NORTHERLY WINDS WILL CONTINUE OVER THE
COASTAL WATERS INTO EARLY MON. THE WINDS WILL BEGIN TO SUBSIDE
DURING THE DAY MON AS A WEAK FRONT APPROACHES...WHICH WILL WEAKEN
THE HIGH PRES THAT HAS BEEN ANCHORED OVER THE NE PAC FOR THE PAST
SEVERAL DAYS. THE FRONT WILL MOVE THROUGH ON TUE AND SHOULD NOT
CAUSE MUCH IN THE WAY OF MARINE CONCERNS. THE NE PAC HIGH
STRENGTHENS AGAIN MIDWEEK BEHIND THE FRONT...WHICH WILL CAUSE THE
GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS TO RETURN FOR TUE
NIGHT AND WED. THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT
MOVES THROUGH THE WATERS.

SEAS WILL REMAIN AROUND 6 TO 8 FT THROUGH TUE. THEY WILL REMAIN
FAIRLY CHOPPY THROUGH TONIGHT DUE TO WIND WAVES BEING GENERATED BY
THE GUSTY NORTHERLY FLOW. THE INCREASING WINDS TUE NIGHT AND WED
WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT FOR A BRIEF PERIOD
BEFORE THEY DROP BACK DOWN ON THU. PYLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 AM PDT MONDAY FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
     8 AM PDT MONDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 192157
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
257 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE CONTINUES TO PROVIDE UNSEASONABLY WARM AND
SUNNY WEATHER TO THE PACIFIC NORTHWEST TODAY...WITH MONDAY EXPECTED
TO BE VERY SIMILAR INLAND. THERMAL LOW PRESSURE WILL SHIFT INLAND
MONDAY...ALLOWING A DEEPER MARINE LAYER TO DEVELOP ALONG THE COAST BY
LATE AFTERNOON. THIS WILL BEGIN A SIGNIFICANT COOLDOWN FOR TUESDAY AS
A DEEP MARINE LAYER PUSHES ONSHORE AHEAD OF AN INCOMING COLD FRONT.
AN UPPER LEVEL TROUGH WILL THEN LINGER THROUGH THE END OF THE
WEEK...KEEPING TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL WITH A
CHANCE OF SHOWERS AT TIMES.

&&

.SHORT TERM...TONIGHT THROUGH WEDNESDAY...VISIBLE SATELLITE IMAGERY
SHOWS CLEAR SKIES YET AGAIN...EXCEPT FOR SOME SLIGHT FILTERING OF THE
SUNSHINE BY SMOKE FROM FIRES IN SOUTHERN SIBERIA LAST WEEK. AS
EXPECTED...IT IS APPEARING THAT SMOKE IS HAVING LITTLE TO NO IMPACT
ON TEMPERATURES TODAY. AS THE SUN ANGLE INCREASED...THE LOSS OF
INSOLATION AS DETECTED BY RAWS STATIONS DECREASED FROM 20-30 PERCENT
LOSS THIS MORNING TO ONLY A 5-10 PERCENT LOSS THIS AFTERNOON. AS A
RESULT TEMPS ARE GENERALLY 0-3 DEG F WARMER THAN THEY WERE YESTERDAY
AT THIS TIME...AND A COUPLE 80 DEGREE READINGS STILL LOOK POSSIBLE
FOR THE INLAND VALLEYS. IF NOT...THERE WILL BE PLENTY OF UPPER 70S.

FOG AND LOW CLOUDS WILL BE MINIMAL AGAIN TONIGHT THOUGH A PATCH OF
COASTAL STRATUS IS DEVELOPING ALONG THE WA COAST. THIS MAY SPREAD
SOME FOG INTO ASTORIA LATER TONIGHT...AND SOME PATCHY RADIATIONAL FOG
MAY DEVELOP AGAIN IN THE NEHALEM RIVER VALLEY AS WELL AS SOME OF THE
COASTAL VALLEYS.

NESDIS ANALYSTS BELIEVE THE SMOKE WILL BE LESS APPARENT MONDAY...
STAYING TO OUR NORTH AS THE UPPER RIDGE AXIS MOVES INTO THE PAC NW.
THEREFORE EXPECT PLENTY OF SUNSHINE AGAIN MONDAY FOR THE INLAND
AREAS. MODELS SHOW 500 MB HEIGHTS DECREASING A BIT MONDAY...BUT TEMPS
REMAIN ABOUT THE SAME AT 850 MB. WITH THE THERMAL TROUGH
OVERHEAD...PLENTY OF SUNSHINE...AND EVEN A LITTLE DOWNSLOPING OFF THE
COAST RANGE AS THE BEGINNINGS OF A SEABREEZE DEVELOP...EXPECT TEMPS
WILL REACH THE LOWER 80S FOR MANY INLAND SITES MONDAY. TEMPS IN
CORVALLIS AND EUGENE MAY BE CAPPED IN THE MID-UPPER 70S AS ONSHORE
FLOW BEGINS TO PUSH THROUGH THE COASTAL VALLEYS BY LATE AFTERNOON.

LOW CLOUDS SHOULD BEGIN DEVELOPING ALONG THE COAST BY LATE MONDAY
AFTERNOON...THEN PUSH INLAND OVERNIGHT MON NIGHT AHEAD OF AN INCOMING
UPPER TROUGH AND ASSOCIATED COLD FRONT. NAM CROSS SECTIONS SHOW A
DEEP MARINE LAYER PUSHING IN MONDAY NIGHT AND EARLY TUE... WITH THE
POTENTIAL FOR ISOLATED SHOWERS TUE AFTERNOON AS THE MARINE LAYER
MIXES/TURNS OVER. TEMPS WILL BE 10-15 DEGREES COOLER TUESDAY DUE TO
THE DEEP ONSHORE FLOW AND MARINE INFLUENCE. THE DEEP MARINE LAYER
WILL KEEP ANY SHOWERS SHALLOW EXCEPT ALONG THE CASCADE CREST WHICH
MAY REMAIN ABOVE THE MARINE INVERSION...WHERE SOME WARMER SURFACE
PARCELS MAY BE MORE BUOYANT FOR DEEPER SHOWERS AND ISOLATED
THUNDERSTORMS. A SIMILAR SITUATION IS EXPECTED WEDNESDAY...WITH A
DEEP MARINE LAYER...BUT PERHAPS A LITTLE MORE OF A TRIGGER FOR
SHOWERS AS THE UPPER TROUGH AXIS DRAGS ACROSS THE PAC NW. ONCE TEMPS
COOL DOWN TUESDAY...EXPECT NEAR TO SLIGHTLY BELOW NORMAL TEMPS TO
PERSIST FOR SEVERAL DAYS.  WEAGLE

.LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY...MODELS ARE HAVING A
HARD TIME WITH THE DETAILS OF WHAT IS LEFT BEHIND AS THE INCOMING
UPPER TROUGH FALLS APART OVER THE PACIFIC NORTHWEST MIDDLE TO LATE
THIS UPCOMING WEEK. IT APPEARS THERE WILL BE ENOUGH OF A WEAKNESS IN
500 MB HEIGHTS AND JUST ENOUGH COOL AIR ALOFT TO MAKE IT DIFFICULT TO
COMPLETELY RULE OUT SHOWERS ANYTIME BETWEEN WED-FRI. 12Z GEM/EC SHOW
A COLD FRONT HOLDING TOGETHER ENOUGH TO BRING A MORE ORGANIZED CHANCE
OF SHOWERS TO OUR NORTHERN ZONES THU NIGHT/FRI. HOWEVER THE 12Z GFS
HAS THIS SYSTEM FALLING APART BEFORE MOVING ONSHORE. RAIN CHANCES
INCREASE NEXT WEEKEND AS MODELS AGREE ON A STRONGER FRONTAL SYSTEM
MOVING ONSHORE...PERHAPS WITH A WEAK TO MODEST ATMOSPHERIC RIVER.
CONFIDENCE IS HIGH ONE THING...AFTER THIS MONDAY THE NEAR- RECORD
WARMTH WILL BE HISTORY AND TEMPS WILL BE MUCH CLOSER TO LATE APRIL
NORMALS.  WEAGLE

&&

.AVIATION...WIDESPREAD VFR CONDITIONS TO CONTINUE TODAY AND
TONIGHT WITH DRY NORTHERLY FLOW. BREEZY WINDS ALONG THE COAST WILL
CONTINUE INTO THIS EVENING...BUT WILL THEN SUBSIDE OVERNIGHT.
PATCHY FOG MAY AGAIN AFFECT THE COASTAL TAF SITES BETWEEN 10Z AND
15Z MON.

KPDX AND APPROACHES...CLEAR AND DRY UNDER HIGH PRES. NO WEATHER
IMPACTS EXPECTED THROUGH MON. BREEZY NW FLOW THROUGH THE AFTERNOON
AND EVENING WILL SUBSIDE OVERNIGHT. PYLE


&&

.MARINE...GUSTY 20 TO 25 KT NORTHERLY WINDS WILL CONTINUE OVER THE
COASTAL WATERS INTO EARLY MON. THE WINDS WILL BEGIN TO SUBSIDE
DURING THE DAY MON AS A WEAK FRONT APPROACHES...WHICH WILL WEAKEN
THE HIGH PRES THAT HAS BEEN ANCHORED OVER THE NE PAC FOR THE PAST
SEVERAL DAYS. THE FRONT WILL MOVE THROUGH ON TUE AND SHOULD NOT
CAUSE MUCH IN THE WAY OF MARINE CONCERNS. THE NE PAC HIGH
STRENGTHENS AGAIN MIDWEEK BEHIND THE FRONT...WHICH WILL CAUSE THE
GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS TO RETURN FOR TUE
NIGHT AND WED. THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT
MOVES THROUGH THE WATERS.

SEAS WILL REMAIN AROUND 6 TO 8 FT THROUGH TUE. THEY WILL REMAIN
FAIRLY CHOPPY THROUGH TONIGHT DUE TO WIND WAVES BEING GENERATED BY
THE GUSTY NORTHERLY FLOW. THE INCREASING WINDS TUE NIGHT AND WED
WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT FOR A BRIEF PERIOD
BEFORE THEY DROP BACK DOWN ON THU. PYLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 AM PDT MONDAY FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
     8 AM PDT MONDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 192157
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
257 PM PDT SUN APR 19 2015

.SYNOPSIS...HIGH PRESSURE CONTINUES TO PROVIDE UNSEASONABLY WARM AND
SUNNY WEATHER TO THE PACIFIC NORTHWEST TODAY...WITH MONDAY EXPECTED
TO BE VERY SIMILAR INLAND. THERMAL LOW PRESSURE WILL SHIFT INLAND
MONDAY...ALLOWING A DEEPER MARINE LAYER TO DEVELOP ALONG THE COAST BY
LATE AFTERNOON. THIS WILL BEGIN A SIGNIFICANT COOLDOWN FOR TUESDAY AS
A DEEP MARINE LAYER PUSHES ONSHORE AHEAD OF AN INCOMING COLD FRONT.
AN UPPER LEVEL TROUGH WILL THEN LINGER THROUGH THE END OF THE
WEEK...KEEPING TEMPERATURES NEAR OR SLIGHTLY BELOW NORMAL WITH A
CHANCE OF SHOWERS AT TIMES.

&&

.SHORT TERM...TONIGHT THROUGH WEDNESDAY...VISIBLE SATELLITE IMAGERY
SHOWS CLEAR SKIES YET AGAIN...EXCEPT FOR SOME SLIGHT FILTERING OF THE
SUNSHINE BY SMOKE FROM FIRES IN SOUTHERN SIBERIA LAST WEEK. AS
EXPECTED...IT IS APPEARING THAT SMOKE IS HAVING LITTLE TO NO IMPACT
ON TEMPERATURES TODAY. AS THE SUN ANGLE INCREASED...THE LOSS OF
INSOLATION AS DETECTED BY RAWS STATIONS DECREASED FROM 20-30 PERCENT
LOSS THIS MORNING TO ONLY A 5-10 PERCENT LOSS THIS AFTERNOON. AS A
RESULT TEMPS ARE GENERALLY 0-3 DEG F WARMER THAN THEY WERE YESTERDAY
AT THIS TIME...AND A COUPLE 80 DEGREE READINGS STILL LOOK POSSIBLE
FOR THE INLAND VALLEYS. IF NOT...THERE WILL BE PLENTY OF UPPER 70S.

FOG AND LOW CLOUDS WILL BE MINIMAL AGAIN TONIGHT THOUGH A PATCH OF
COASTAL STRATUS IS DEVELOPING ALONG THE WA COAST. THIS MAY SPREAD
SOME FOG INTO ASTORIA LATER TONIGHT...AND SOME PATCHY RADIATIONAL FOG
MAY DEVELOP AGAIN IN THE NEHALEM RIVER VALLEY AS WELL AS SOME OF THE
COASTAL VALLEYS.

NESDIS ANALYSTS BELIEVE THE SMOKE WILL BE LESS APPARENT MONDAY...
STAYING TO OUR NORTH AS THE UPPER RIDGE AXIS MOVES INTO THE PAC NW.
THEREFORE EXPECT PLENTY OF SUNSHINE AGAIN MONDAY FOR THE INLAND
AREAS. MODELS SHOW 500 MB HEIGHTS DECREASING A BIT MONDAY...BUT TEMPS
REMAIN ABOUT THE SAME AT 850 MB. WITH THE THERMAL TROUGH
OVERHEAD...PLENTY OF SUNSHINE...AND EVEN A LITTLE DOWNSLOPING OFF THE
COAST RANGE AS THE BEGINNINGS OF A SEABREEZE DEVELOP...EXPECT TEMPS
WILL REACH THE LOWER 80S FOR MANY INLAND SITES MONDAY. TEMPS IN
CORVALLIS AND EUGENE MAY BE CAPPED IN THE MID-UPPER 70S AS ONSHORE
FLOW BEGINS TO PUSH THROUGH THE COASTAL VALLEYS BY LATE AFTERNOON.

LOW CLOUDS SHOULD BEGIN DEVELOPING ALONG THE COAST BY LATE MONDAY
AFTERNOON...THEN PUSH INLAND OVERNIGHT MON NIGHT AHEAD OF AN INCOMING
UPPER TROUGH AND ASSOCIATED COLD FRONT. NAM CROSS SECTIONS SHOW A
DEEP MARINE LAYER PUSHING IN MONDAY NIGHT AND EARLY TUE... WITH THE
POTENTIAL FOR ISOLATED SHOWERS TUE AFTERNOON AS THE MARINE LAYER
MIXES/TURNS OVER. TEMPS WILL BE 10-15 DEGREES COOLER TUESDAY DUE TO
THE DEEP ONSHORE FLOW AND MARINE INFLUENCE. THE DEEP MARINE LAYER
WILL KEEP ANY SHOWERS SHALLOW EXCEPT ALONG THE CASCADE CREST WHICH
MAY REMAIN ABOVE THE MARINE INVERSION...WHERE SOME WARMER SURFACE
PARCELS MAY BE MORE BUOYANT FOR DEEPER SHOWERS AND ISOLATED
THUNDERSTORMS. A SIMILAR SITUATION IS EXPECTED WEDNESDAY...WITH A
DEEP MARINE LAYER...BUT PERHAPS A LITTLE MORE OF A TRIGGER FOR
SHOWERS AS THE UPPER TROUGH AXIS DRAGS ACROSS THE PAC NW. ONCE TEMPS
COOL DOWN TUESDAY...EXPECT NEAR TO SLIGHTLY BELOW NORMAL TEMPS TO
PERSIST FOR SEVERAL DAYS.  WEAGLE

.LONG TERM...WEDNESDAY NIGHT THROUGH SATURDAY...MODELS ARE HAVING A
HARD TIME WITH THE DETAILS OF WHAT IS LEFT BEHIND AS THE INCOMING
UPPER TROUGH FALLS APART OVER THE PACIFIC NORTHWEST MIDDLE TO LATE
THIS UPCOMING WEEK. IT APPEARS THERE WILL BE ENOUGH OF A WEAKNESS IN
500 MB HEIGHTS AND JUST ENOUGH COOL AIR ALOFT TO MAKE IT DIFFICULT TO
COMPLETELY RULE OUT SHOWERS ANYTIME BETWEEN WED-FRI. 12Z GEM/EC SHOW
A COLD FRONT HOLDING TOGETHER ENOUGH TO BRING A MORE ORGANIZED CHANCE
OF SHOWERS TO OUR NORTHERN ZONES THU NIGHT/FRI. HOWEVER THE 12Z GFS
HAS THIS SYSTEM FALLING APART BEFORE MOVING ONSHORE. RAIN CHANCES
INCREASE NEXT WEEKEND AS MODELS AGREE ON A STRONGER FRONTAL SYSTEM
MOVING ONSHORE...PERHAPS WITH A WEAK TO MODEST ATMOSPHERIC RIVER.
CONFIDENCE IS HIGH ONE THING...AFTER THIS MONDAY THE NEAR- RECORD
WARMTH WILL BE HISTORY AND TEMPS WILL BE MUCH CLOSER TO LATE APRIL
NORMALS.  WEAGLE

&&

.AVIATION...WIDESPREAD VFR CONDITIONS TO CONTINUE TODAY AND
TONIGHT WITH DRY NORTHERLY FLOW. BREEZY WINDS ALONG THE COAST WILL
CONTINUE INTO THIS EVENING...BUT WILL THEN SUBSIDE OVERNIGHT.
PATCHY FOG MAY AGAIN AFFECT THE COASTAL TAF SITES BETWEEN 10Z AND
15Z MON.

KPDX AND APPROACHES...CLEAR AND DRY UNDER HIGH PRES. NO WEATHER
IMPACTS EXPECTED THROUGH MON. BREEZY NW FLOW THROUGH THE AFTERNOON
AND EVENING WILL SUBSIDE OVERNIGHT. PYLE


&&

.MARINE...GUSTY 20 TO 25 KT NORTHERLY WINDS WILL CONTINUE OVER THE
COASTAL WATERS INTO EARLY MON. THE WINDS WILL BEGIN TO SUBSIDE
DURING THE DAY MON AS A WEAK FRONT APPROACHES...WHICH WILL WEAKEN
THE HIGH PRES THAT HAS BEEN ANCHORED OVER THE NE PAC FOR THE PAST
SEVERAL DAYS. THE FRONT WILL MOVE THROUGH ON TUE AND SHOULD NOT
CAUSE MUCH IN THE WAY OF MARINE CONCERNS. THE NE PAC HIGH
STRENGTHENS AGAIN MIDWEEK BEHIND THE FRONT...WHICH WILL CAUSE THE
GUSTY SMALL CRAFT ADVISORY NORTHERLY WINDS TO RETURN FOR TUE
NIGHT AND WED. THE WINDS WEAKEN AGAIN ON THU AS ANOTHER WEAK FRONT
MOVES THROUGH THE WATERS.

SEAS WILL REMAIN AROUND 6 TO 8 FT THROUGH TUE. THEY WILL REMAIN
FAIRLY CHOPPY THROUGH TONIGHT DUE TO WIND WAVES BEING GENERATED BY
THE GUSTY NORTHERLY FLOW. THE INCREASING WINDS TUE NIGHT AND WED
WILL LIKELY PUSH THE SEAS BACK UP AROUND 10 FT FOR A BRIEF PERIOD
BEFORE THEY DROP BACK DOWN ON THU. PYLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 AM PDT MONDAY FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO
     8 AM PDT MONDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KOTX 192116
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
216 PM PDT SUN APR 19 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and cooler temperatures. After this, a number of potential waves
track across the Inland Northwest. The heaviest amounts of rain
will fall across North Idaho, with snow levels high enough to not
pose a threat to any regional passes.

&&

.DISCUSSION...
Tonight through Tuesday...Satellite indicates dry northwest flow
aloft under the east flank of an approaching upper level ridge.
This will be the main driver of sensible weather for the next two
days...featuring mainly clear skies...light winds and increasingly
warm temperatures with widespread low to mid 70s by Tuesday
afternoon. There is not much else to elaborate on for this period.

Tuesday night through Wednesday night...This period will bring a
change to the dry and warm weather stretch. Models are in
agreement in dragging a moderate strength upper level trough
through the region beginning with a chance of showers or a stray
thunderstorms Tuesday evening/night over the high Cascades with a
general spreading out of this precipitation risk through the
basin on Wednesday and into the Idaho Panhandle Wednesday night.
This does not look like a significant precipitation maker with
fairly weak dynamic support and marginal deep moisture
availability and instability. The ECMWF model is the most
aggressive and fastest model which implies a better chance of
showers and isolated afternoon and evening thunderstorms...while
the GFS is slower and weaker. While confidence is growing that
Wednesday will feature at least more clouds and slightly cooler
temperatures with a few showers...confidence is low regarding
which model is more plausible at this time. /Fugazzi

Thursday through Sunday: A weak front will move through the area
early Thursday. By Thur afternoon the GFS is showing some decent
instability along the border btwn ID and MT. Have kept
thunderstorms in through the afternoon hours. But thereafter the
models are not in very good agreement about the rest of the work
week and next weekend. The 12Z ECMWF brings a large trough of low
pressure through the Pacific Northwest late Thur night through
early Sat morning. It then builds a shortwave ridge over the area
for Saturday and Sunday. Whereas the 12Z gfs brings several
fairly weak waves through broad southwest flow through Sunday.
Needless to say there is high uncertainty in the extended period.
Kept chance of precipitation around average for this time of the
year....meaning a slight chance in most valleys and a chance of
precip in the mountains. Thursday daytime highs should be a few
degrees above average. Then through the remainder of the forecast
period temps will be right around average for this time of the
year. /Nisbet

&&

.AVIATION...
18Z TAFS: High pressure building into the region will result in
VFR conditions. Winds will remain weak and some passing high
cirrus can be expected to drop south into the region out of BC.
/MJF

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        42  72  45  75  50  70 /   0   0   0   0  10  20
Coeur d`Alene  37  70  41  75  44  70 /   0   0   0   0  10  30
Pullman        39  69  40  74  46  67 /   0   0   0   0  10  20
Lewiston       44  76  46  78  49  72 /   0   0   0   0  10  20
Colville       40  74  41  77  46  73 /   0   0   0   0  10  30
Sandpoint      35  69  37  73  40  71 /   0   0   0   0  10  30
Kellogg        37  68  39  74  43  70 /   0   0   0   0  10  40
Moses Lake     42  76  43  78  50  74 /   0   0   0   0  10  20
Wenatchee      48  76  50  77  53  72 /   0   0   0  10  10  20
Omak           42  76  43  77  47  73 /   0   0   0  10  10  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&




000
FXUS66 KOTX 192116
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
216 PM PDT SUN APR 19 2015

.SYNOPSIS...
Warm, dry weather is expected through Tuesday. Temperatures are
expected to be more than ten degrees above average. The arrival
of a cold front Wednesday will bring the first threat for showers
and cooler temperatures. After this, a number of potential waves
track across the Inland Northwest. The heaviest amounts of rain
will fall across North Idaho, with snow levels high enough to not
pose a threat to any regional passes.

&&

.DISCUSSION...
Tonight through Tuesday...Satellite indicates dry northwest flow
aloft under the east flank of an approaching upper level ridge.
This will be the main driver of sensible weather for the next two
days...featuring mainly clear skies...light winds and increasingly
warm temperatures with widespread low to mid 70s by Tuesday
afternoon. There is not much else to elaborate on for this period.

Tuesday night through Wednesday night...This period will bring a
change to the dry and warm weather stretch. Models are in
agreement in dragging a moderate strength upper level trough
through the region beginning with a chance of showers or a stray
thunderstorms Tuesday evening/night over the high Cascades with a
general spreading out of this precipitation risk through the
basin on Wednesday and into the Idaho Panhandle Wednesday night.
This does not look like a significant precipitation maker with
fairly weak dynamic support and marginal deep moisture
availability and instability. The ECMWF model is the most
aggressive and fastest model which implies a better chance of
showers and isolated afternoon and evening thunderstorms...while
the GFS is slower and weaker. While confidence is growing that
Wednesday will feature at least more clouds and slightly cooler
temperatures with a few showers...confidence is low regarding
which model is more plausible at this time. /Fugazzi

Thursday through Sunday: A weak front will move through the area
early Thursday. By Thur afternoon the GFS is showing some decent
instability along the border btwn ID and MT. Have kept
thunderstorms in through the afternoon hours. But thereafter the
models are not in very good agreement about the rest of the work
week and next weekend. The 12Z ECMWF brings a large trough of low
pressure through the Pacific Northwest late Thur night through
early Sat morning. It then builds a shortwave ridge over the area
for Saturday and Sunday. Whereas the 12Z gfs brings several
fairly weak waves through broad southwest flow through Sunday.
Needless to say there is high uncertainty in the extended period.
Kept chance of precipitation around average for this time of the
year....meaning a slight chance in most valleys and a chance of
precip in the mountains. Thursday daytime highs should be a few
degrees above average. Then through the remainder of the forecast
period temps will be right around average for this time of the
year. /Nisbet

&&

.AVIATION...
18Z TAFS: High pressure building into the region will result in
VFR conditions. Winds will remain weak and some passing high
cirrus can be expected to drop south into the region out of BC.
/MJF

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        42  72  45  75  50  70 /   0   0   0   0  10  20
Coeur d`Alene  37  70  41  75  44  70 /   0   0   0   0  10  30
Pullman        39  69  40  74  46  67 /   0   0   0   0  10  20
Lewiston       44  76  46  78  49  72 /   0   0   0   0  10  20
Colville       40  74  41  77  46  73 /   0   0   0   0  10  30
Sandpoint      35  69  37  73  40  71 /   0   0   0   0  10  30
Kellogg        37  68  39  74  43  70 /   0   0   0   0  10  40
Moses Lake     42  76  43  78  50  74 /   0   0   0   0  10  20
Wenatchee      48  76  50  77  53  72 /   0   0   0  10  10  20
Omak           42  76  43  77  47  73 /   0   0   0  10  10  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&





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