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000
FXUS66 KPQR 260310
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
810 PM PDT SAT APR 25 2015

.SYNOPSIS...THE UPPER LOW THAT HAS BROUGHT SHOWERS TO SOUTHWEST
WASHINGTON AND NORTHWEST OREGON THE PAST FEW DAYS IS MOVING EAST
THROUGH CENTRAL AND EASTERN WASHINGTON THIS EVENING WITH DECREASING
SHOWERS OVER OUR FORECAST AREA AS HIGHER PRESSURE MOVES IN. LOOK FOR
PARTIAL CLEARING AND SOME LOCAL FOG AND LOW CLOUDS LATER TONIGHT AND
SUNDAY MORNING. A WARM FRONT WILL BRUSH THE NORTHWEST PART OF THE
FORECAST AREA ESPECIALLY SUNDAY AND SUNDAY EVENING...MAINLY THE COAST
BUT POSSIBLY CLOSE TO PORTLAND. THE WARM FRONT LIFTS NORTH BY MONDAY
AS AN UPPER RIDGE BUILDS IN FROM THE SOUTH FOR SIGNIFICANT WARMING.
THE NEXT COLD FRONT LOOKS TO BRING RAIN EARLY TUESDAY FOLLOWED BY
AFTERNOON SHOWERS. MORE SHOWERS ARE POSSIBLE FOR THE REST OF THE WEEK
AS ANOTHER UPPER LEVEL TROUGH SETTLES NEAR THE PACIFIC NORTHWEST.
&&

.SHORT TERM...TONIGHT THROUGH TUESDAY...WE DID GET ISOLATED
CONVECTION AROUND THE AREA MAINLY FROM THE EAST SLOPES OF THE COASTAL
MOUNTAINS WESTWARD...AND FROM ABOUT LINN COUNTY NORTHWARD. DID GET
ONE REPORT OF THUNDER NORTHEAST OF DOWNTOWN PORTLAND OTHERWISE
LIGHTNING HAS BEEN SPARSE. AS THE RESPONSIBLE UPPER LOW CONTINUES
MOVING EAST THROUGH CENTRAL AND EASTERN WASHINGTON... EXPECT THE LAST
REMAINING SHOWERS TO FINISH SETTLING DOWN IN THE NEXT HOUR OR TWO IN
COMBINATION WITH LOSING OUR DAYTIME HEATING.

AFTER THAT...LOOK FOR PARTIAL CLEARING THE REMAINDER OF TONIGHT AS A
WEAK UPPER RIDGE MOVES IN. BUT THAT COULD LEAD TO SOME LOCAL FOG OR
LOW CLOUDS. ALSO...DEWPOINTS HAVE LOWERED IN MANY AREAS INTO THE
30S...SO LOOK FOR A COOL NIGHT TONIGHT WITH SEVERAL AREAS IN THE 30S
EARLY SUNDAY.

THE MODELS STILL SAY A WARM FRONT WILL RIDE OVER THE UPPER RIDGE AND
BRUSH OUR FORECAST AREA SUNDAY AND SUNDAY NIGHT. THE MODELS HAVE BEEN
SLOWING DOWN THE ARRIVAL AND INLAND SPREAD OF THE LIGHT RAIN. SOME
LIGHT PRECIPITATION MIGHT REACH THE COAST BY LATE MORNING AND SPREAD
INLAND MAINLY NORTH OF SALEM IN THE AFTERNOON AND EVENING... BUT THE
BEST CHANCE WILL BE NEAR THE NORTHERN HALF OF OUR COAST. THE AIR MASS
WILL BE WARMING...SO WE SHOULD SEE TEMPS UP A FEW DEGREES ON SUNDAY
FROM THOSE TODAY.

THE WARM FRONT LIFTS NORTH OF OUR AREA LATER SUNDAY NIGHT AND MONDAY
MORNING FOR DRYING...WITH CLOUDS DECREASING FROM SOUTH TO NORTH ON
MONDAY. THE AIR MASS WILL CONTINUE TO WARM MONDAY...AND WE HAVE A
CHANCE OF GETTING CLOSE TO 80 AGAIN IN SOME OF OUR INLAND VALLEYS.

THE MODELS ARE SHOWING THE NEXT COLD FRONT APPROACHING THE COAST LATE
MONDAY NIGHT AND MOVING THROUGH THE FORECAST AREA TUESDAY... FASTER
THAN THE MODELS JUST 24 TO 48 HOURS AGO. SNOW LEVELS WILL APPROACH
PASS ELEVATIONS AFTER THE FRONT MOVES THROUGH LATE TUESDAY OR TUESDAY
NIGHT...BUT PRECIPITATION WILL BE WANING SO ANY SNOW ACCUMULATIONS
LOOK LIGHT. TOLLESON

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
TUESDAY NIGHT THROUGH SATURDAY...SOME SHOWERS MAY LINGER EARLY
TUESDAY NIGHT BEHIND THE COLD FRONT BUT THESE WILL BE CONFINED MOSTLY
TO THE CASCADES BEFORE COMING TO AN END BY EARLY WEDNESDAY. THE
WEATHER PATTERN WEDNESDAY THROUGH FRIDAY WILL BE MARKED BY A MEAN
RIDGE OVER THE CENTRAL CONUS WITH A MEAN TROUGH MOVING INTO THE WEST.
IN GENERAL...THIS WILL LEAD TO A MORE PROGRESSIVE PATTERN BUT
SIGNIFICANT VARIATION AMONG OPERATIONAL FORECAST MODELS...AND THEIR
ENSEMBLE MEMBERS...KEEPS THE CONFIDENCE IN THE PARTICULARS OF THE
FORECAST BELOW NORMAL FOR THE SECOND HALF OF NEXT WEEK. MADE SOME
SLIGHT CHANGES TO POPS...DRYING OUT THE COAST AND VALLEYS FOR
WEDNESDAY BUT MAINTAINING CHANCE POPS THURSDAY AND FRIDAY. SLIGHTLY
INCREASED POPS THURSDAY NIGHT AS THE GEFS MEAN AND ECMWF QPF
FORECASTS SEEM TO SUPPORT ENHANCED SHOWER ACTIVITY...THOUGH PERHAPS
FOR DIFFERENT REASONS /TIMING OF SHORTWAVE VS. FRONTAL PASSAGE/.
NONETHELESS...THE TIMING OF SHORTWAVES AND WHEN THE UPPER TROUGH
SHIFTS INLAND STILL CREATE SOME CONSIDERABLE UNCERTAINTY IN THE
EXTENDED FORECAST PERIOD. TEMPERATURES GENERALLY TREND NEAR OR
SLIGHTLY BELOW SEASONAL NORMALS THROUGH THE SECOND HALF OF NEXT WEEK.
  CULLEN
&&

.AVIATION...PREDOMINANTLY VFR THIS EVENING. ISOLATED -SHRA COMING OFF
THE N OREGON COAST RANGE INTO THE N WILLAMETTE VALLEY AND ALSO A FEW
OTHERS IN THE N AND CENTRAL OREGON CASCADES AND FOOTHILLS. RADAR
TRENDS SHOW THESE SHOWERS WEAKENING WITH THE LOSS OF SOLAR HEATING.
EXPECT VFR OVERNIGHT THROUGH SUN AFTERNOON...EXCEPT FOR LOCALIZED IFR
VIS DUE TO FOG LATE TONIGHT THROUGH ABOUT 17Z SUN ALONG THE COAST AND
INTERIOR VALLEYS. INCREASING MID AND HIGH CLOUDS SPREAD OVER THE AREA
LATE TONIGHT THROUGH SUN ASSOCIATED WITH AN APPROACHING WARM FRONT.
AREAS OF MVFR LIKELY ALONG THE S WA AND N OREGON COAST SUN AFTERNOON.


KPDX AND APPROACHES...ISOLATED CELL JUST S OF THE TERMINAL AND MOVING
SE CONTINUES TO WEAKEN. BKN-OVC CIGS AS OF 03Z WILL BECOME A SCT
LAYER WITHIN THE NEXT COUPLE HOURS. EXPECT CLEAR SKIES
OVERNIGHT...WHICH GIVES THE POSSIBILITY OF FOG/LOW STRATUS FORMING
AROUND THE OPS AREA AFT 10Z...ESPECIALLY TO W AND N OF KPDX. EXPECT
AREAS OF IFR CLOUDS INTO SUN AM...BUT NOT CONFIDENT ON HOW LONG THESE
PERSIST DUE TO INCREASING MID/HIGH CLOUDS VERY LATE TONIGHT AND SUN
AM. WEISHAAR
&&

.MARINE...WIND SPEEDS 10 KT OR LESS THROUGH TONIGHT WITH SURFACE HIGH
PRES OVER THE WATERS. A WARM FRONT WILL MOVE N ACROSS THE WATERS SUN.
S WIND INCREASES LATE SUN MORNING THROUGH MID- AFTERNOON. CURRENT
SMALL CRAFT ADVISORY FOR WIND LOOKS GOOD. STRONGEST WIND SPEEDS TO BE
IN THE OUTER NRN WATERS. WIND WILL DIMINISH SUN NIGHT AS THE WARM
FRONT CONTINUES TO LIFT N THROUGH THE WASHINGTON WATERS.

ANOTHER BREAK IS EXPECTED ON MON BEFORE THE NEXT FRONT ARRIVES MON
NIGHT OR TUE. FRONT DOES NOT LOOK ALL THAT IMPRESSIVE IN THE FCST
MODELS...BUT ANOTHER ROUND OF LOW END SMALL CRAFT ADVISORY WIND IS
CURRENTLY BEING ADVERTISED. FCST CONFIDENCE DECREASES FOR THE LATTER
HALF OF NEXT WEEK...BUT NO MAJOR WEATHER SYSTEMS ARE CURRENTLY
EXPECTED.

SEAS REMAIN BELOW 10 FT FOR THE NEXT FEW DAYS. LIKELY TO SEE SOME
MIXED SEA CONDITIONS OVER THE NRN OUTER WATERS SUN AFTERNOON...WITH
WIND WAVES REACHING 5 TO 6 FT OUT OF THE S-SW AND A WEST LONGER
PERIOD FRESH SWELL. WEISHAAR
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM NOON TO 11 PM PDT SUNDAY
     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 260310
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
810 PM PDT SAT APR 25 2015

.SYNOPSIS...THE UPPER LOW THAT HAS BROUGHT SHOWERS TO SOUTHWEST
WASHINGTON AND NORTHWEST OREGON THE PAST FEW DAYS IS MOVING EAST
THROUGH CENTRAL AND EASTERN WASHINGTON THIS EVENING WITH DECREASING
SHOWERS OVER OUR FORECAST AREA AS HIGHER PRESSURE MOVES IN. LOOK FOR
PARTIAL CLEARING AND SOME LOCAL FOG AND LOW CLOUDS LATER TONIGHT AND
SUNDAY MORNING. A WARM FRONT WILL BRUSH THE NORTHWEST PART OF THE
FORECAST AREA ESPECIALLY SUNDAY AND SUNDAY EVENING...MAINLY THE COAST
BUT POSSIBLY CLOSE TO PORTLAND. THE WARM FRONT LIFTS NORTH BY MONDAY
AS AN UPPER RIDGE BUILDS IN FROM THE SOUTH FOR SIGNIFICANT WARMING.
THE NEXT COLD FRONT LOOKS TO BRING RAIN EARLY TUESDAY FOLLOWED BY
AFTERNOON SHOWERS. MORE SHOWERS ARE POSSIBLE FOR THE REST OF THE WEEK
AS ANOTHER UPPER LEVEL TROUGH SETTLES NEAR THE PACIFIC NORTHWEST.
&&

.SHORT TERM...TONIGHT THROUGH TUESDAY...WE DID GET ISOLATED
CONVECTION AROUND THE AREA MAINLY FROM THE EAST SLOPES OF THE COASTAL
MOUNTAINS WESTWARD...AND FROM ABOUT LINN COUNTY NORTHWARD. DID GET
ONE REPORT OF THUNDER NORTHEAST OF DOWNTOWN PORTLAND OTHERWISE
LIGHTNING HAS BEEN SPARSE. AS THE RESPONSIBLE UPPER LOW CONTINUES
MOVING EAST THROUGH CENTRAL AND EASTERN WASHINGTON... EXPECT THE LAST
REMAINING SHOWERS TO FINISH SETTLING DOWN IN THE NEXT HOUR OR TWO IN
COMBINATION WITH LOSING OUR DAYTIME HEATING.

AFTER THAT...LOOK FOR PARTIAL CLEARING THE REMAINDER OF TONIGHT AS A
WEAK UPPER RIDGE MOVES IN. BUT THAT COULD LEAD TO SOME LOCAL FOG OR
LOW CLOUDS. ALSO...DEWPOINTS HAVE LOWERED IN MANY AREAS INTO THE
30S...SO LOOK FOR A COOL NIGHT TONIGHT WITH SEVERAL AREAS IN THE 30S
EARLY SUNDAY.

THE MODELS STILL SAY A WARM FRONT WILL RIDE OVER THE UPPER RIDGE AND
BRUSH OUR FORECAST AREA SUNDAY AND SUNDAY NIGHT. THE MODELS HAVE BEEN
SLOWING DOWN THE ARRIVAL AND INLAND SPREAD OF THE LIGHT RAIN. SOME
LIGHT PRECIPITATION MIGHT REACH THE COAST BY LATE MORNING AND SPREAD
INLAND MAINLY NORTH OF SALEM IN THE AFTERNOON AND EVENING... BUT THE
BEST CHANCE WILL BE NEAR THE NORTHERN HALF OF OUR COAST. THE AIR MASS
WILL BE WARMING...SO WE SHOULD SEE TEMPS UP A FEW DEGREES ON SUNDAY
FROM THOSE TODAY.

THE WARM FRONT LIFTS NORTH OF OUR AREA LATER SUNDAY NIGHT AND MONDAY
MORNING FOR DRYING...WITH CLOUDS DECREASING FROM SOUTH TO NORTH ON
MONDAY. THE AIR MASS WILL CONTINUE TO WARM MONDAY...AND WE HAVE A
CHANCE OF GETTING CLOSE TO 80 AGAIN IN SOME OF OUR INLAND VALLEYS.

THE MODELS ARE SHOWING THE NEXT COLD FRONT APPROACHING THE COAST LATE
MONDAY NIGHT AND MOVING THROUGH THE FORECAST AREA TUESDAY... FASTER
THAN THE MODELS JUST 24 TO 48 HOURS AGO. SNOW LEVELS WILL APPROACH
PASS ELEVATIONS AFTER THE FRONT MOVES THROUGH LATE TUESDAY OR TUESDAY
NIGHT...BUT PRECIPITATION WILL BE WANING SO ANY SNOW ACCUMULATIONS
LOOK LIGHT. TOLLESON

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
TUESDAY NIGHT THROUGH SATURDAY...SOME SHOWERS MAY LINGER EARLY
TUESDAY NIGHT BEHIND THE COLD FRONT BUT THESE WILL BE CONFINED MOSTLY
TO THE CASCADES BEFORE COMING TO AN END BY EARLY WEDNESDAY. THE
WEATHER PATTERN WEDNESDAY THROUGH FRIDAY WILL BE MARKED BY A MEAN
RIDGE OVER THE CENTRAL CONUS WITH A MEAN TROUGH MOVING INTO THE WEST.
IN GENERAL...THIS WILL LEAD TO A MORE PROGRESSIVE PATTERN BUT
SIGNIFICANT VARIATION AMONG OPERATIONAL FORECAST MODELS...AND THEIR
ENSEMBLE MEMBERS...KEEPS THE CONFIDENCE IN THE PARTICULARS OF THE
FORECAST BELOW NORMAL FOR THE SECOND HALF OF NEXT WEEK. MADE SOME
SLIGHT CHANGES TO POPS...DRYING OUT THE COAST AND VALLEYS FOR
WEDNESDAY BUT MAINTAINING CHANCE POPS THURSDAY AND FRIDAY. SLIGHTLY
INCREASED POPS THURSDAY NIGHT AS THE GEFS MEAN AND ECMWF QPF
FORECASTS SEEM TO SUPPORT ENHANCED SHOWER ACTIVITY...THOUGH PERHAPS
FOR DIFFERENT REASONS /TIMING OF SHORTWAVE VS. FRONTAL PASSAGE/.
NONETHELESS...THE TIMING OF SHORTWAVES AND WHEN THE UPPER TROUGH
SHIFTS INLAND STILL CREATE SOME CONSIDERABLE UNCERTAINTY IN THE
EXTENDED FORECAST PERIOD. TEMPERATURES GENERALLY TREND NEAR OR
SLIGHTLY BELOW SEASONAL NORMALS THROUGH THE SECOND HALF OF NEXT WEEK.
  CULLEN
&&

.AVIATION...PREDOMINANTLY VFR THIS EVENING. ISOLATED -SHRA COMING OFF
THE N OREGON COAST RANGE INTO THE N WILLAMETTE VALLEY AND ALSO A FEW
OTHERS IN THE N AND CENTRAL OREGON CASCADES AND FOOTHILLS. RADAR
TRENDS SHOW THESE SHOWERS WEAKENING WITH THE LOSS OF SOLAR HEATING.
EXPECT VFR OVERNIGHT THROUGH SUN AFTERNOON...EXCEPT FOR LOCALIZED IFR
VIS DUE TO FOG LATE TONIGHT THROUGH ABOUT 17Z SUN ALONG THE COAST AND
INTERIOR VALLEYS. INCREASING MID AND HIGH CLOUDS SPREAD OVER THE AREA
LATE TONIGHT THROUGH SUN ASSOCIATED WITH AN APPROACHING WARM FRONT.
AREAS OF MVFR LIKELY ALONG THE S WA AND N OREGON COAST SUN AFTERNOON.


KPDX AND APPROACHES...ISOLATED CELL JUST S OF THE TERMINAL AND MOVING
SE CONTINUES TO WEAKEN. BKN-OVC CIGS AS OF 03Z WILL BECOME A SCT
LAYER WITHIN THE NEXT COUPLE HOURS. EXPECT CLEAR SKIES
OVERNIGHT...WHICH GIVES THE POSSIBILITY OF FOG/LOW STRATUS FORMING
AROUND THE OPS AREA AFT 10Z...ESPECIALLY TO W AND N OF KPDX. EXPECT
AREAS OF IFR CLOUDS INTO SUN AM...BUT NOT CONFIDENT ON HOW LONG THESE
PERSIST DUE TO INCREASING MID/HIGH CLOUDS VERY LATE TONIGHT AND SUN
AM. WEISHAAR
&&

.MARINE...WIND SPEEDS 10 KT OR LESS THROUGH TONIGHT WITH SURFACE HIGH
PRES OVER THE WATERS. A WARM FRONT WILL MOVE N ACROSS THE WATERS SUN.
S WIND INCREASES LATE SUN MORNING THROUGH MID- AFTERNOON. CURRENT
SMALL CRAFT ADVISORY FOR WIND LOOKS GOOD. STRONGEST WIND SPEEDS TO BE
IN THE OUTER NRN WATERS. WIND WILL DIMINISH SUN NIGHT AS THE WARM
FRONT CONTINUES TO LIFT N THROUGH THE WASHINGTON WATERS.

ANOTHER BREAK IS EXPECTED ON MON BEFORE THE NEXT FRONT ARRIVES MON
NIGHT OR TUE. FRONT DOES NOT LOOK ALL THAT IMPRESSIVE IN THE FCST
MODELS...BUT ANOTHER ROUND OF LOW END SMALL CRAFT ADVISORY WIND IS
CURRENTLY BEING ADVERTISED. FCST CONFIDENCE DECREASES FOR THE LATTER
HALF OF NEXT WEEK...BUT NO MAJOR WEATHER SYSTEMS ARE CURRENTLY
EXPECTED.

SEAS REMAIN BELOW 10 FT FOR THE NEXT FEW DAYS. LIKELY TO SEE SOME
MIXED SEA CONDITIONS OVER THE NRN OUTER WATERS SUN AFTERNOON...WITH
WIND WAVES REACHING 5 TO 6 FT OUT OF THE S-SW AND A WEST LONGER
PERIOD FRESH SWELL. WEISHAAR
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM NOON TO 11 PM PDT SUNDAY
     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 252135
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
234 PM PDT SAT APR 25 2015

.SYNOPSIS...THE UPPER LOW WILL CONTINUE WEAKENING AND MOVE EAST BY
EARLY THIS EVENING AS BUILDING HIGH PRESSURE BRINGS A SWIFT END TO
ANY LINGERING SHOWERS. A WARM FRONT WILL MAINLY CLIP THE NORTHERN
COASTAL AREAS WITH SOME LIGHT RAIN SUNDAY. MONDAY WILL BE DRIER AND
MUCH WARMER AS A STRONG UPPER LEVEL RIDGE BUILDS IN FROM THE SOUTH.
THE NEXT COLD FRONT LOOKS TO BRING RAIN EARLY TUESDAY FOLLOWED BY
AFTERNOON SHOWERS. MORE SHOWERS ARE POSSIBLE FOR THE REST OF THE
WEEK AS ANOTHER UPPER LEVEL TROUGH SETTLES NEAR THE PACIFIC
NORTHWEST.

&&

.SHORT TERM...TONIGHT THROUGH TUESDAY...CONVECTION HAS BEEN LESS
THAN STELLAR IN STRENGTH THUS FAR TODAY. COVERAGE HAS MET
EXPECTATIONS THOUGH WITH SOME SHOWERS OVER THE SOUTH VALLEY
PRODUCING A QUICK TENTH OR TWO OF RAIN OVER THE LAST COUPLE HOURS.
AM NOT READY TO COMPLETELY GIVE UP ON A THUNDER THREAT FOR THE NEXT
FEW HOURS BUT HAVE CERTAINLY LOST MOST OF THE EXCITEMENT BUILT OVER
THE LAST COUPLE DAYS. WATER VAPOR IMAGERY IS SHOWING THE LEADING
UPPER EDGE OF THE ENCROACHING WARM FRONT ABOUT TO CROSS THE MOUTH OF
THE COLUMBIA. THIS IS FURTHER INDICATION THAT MID LEVEL SUBSIDENCE
IS BECOMING DOMINANT. AS SUCH...STILL EXPECT SHOWERS WILL QUICKLY
DIMINISH THIS AFTERNOON. FOR ADDED CONFIDENCE...THE SPC STORM SCALE
ENSEMBLE OF OPPORTUNITY MEMBERS BACK THIS NOTION UP AND GENERALLY
CEASE ALL SHOWERS EVEN OVER THE CASCADES BY ABOUT 8 PM.

THE CLOUDS ASSOCIATED WITH THE APPROACHING WARM FRONT APPEAR TO STAY
OFFSHORE ENOUGH TO GIVE DECENT CLEARING FOR A LARGE PART OF THE LATE
EVENING AND OVERNIGHT HOURS. THEREFORE ADDED SOME PATCHY FOG ACROSS
THE REST OF THE LOWER ELEVATIONS AND INCLUDING THE COAST. FORECASTED
TEMPERATURES FOR TONIGHT WERE ALREADY CLOSE TO THE DEW POINTS SO
DIDN`T SEE A NEED TO LOWER THE LOWS.

SUNDAY WILL STAY DRY FOR THE BULK OF THE CWA AS MODELS CONTINUE TO
SHUNT THE APPROACHING WARM FRONT EVER SO GRADUALLY FURTHER NORTH.
STILL MAINTAINED AROUND A 30 PCT POP FOR THE COAST RANGE DURING THE
AFTERNOON AND ABOUT A 60 PCT FOR THE NORTH COAST SUNDAY EVENING BUT
FEEL LIKE THIS IS A CASE WHERE ITS BETTER TO SAY THERE IS A 70 PCT
AND 40 PCT CHANCE RESPECTIVELY IT WILL NOT RAIN TOMORROW. WOULD NOT
BE SURPRISED IF FOLLOWING SHIFTS LOWER POPS YET FURTHER BASED ON
LATER MODEL RUNS. CLEARING SKIES WILL AGAIN ALLOW FOR SOME FOG
DEVELOPMENT LATE OVERNIGHT SUNDAY AND INTO EARLY MONDAY DAYLIGHT
HOURS.

THE UPPER RIDGE OVER THE REGION WILL BE FAIRLY TRANSITORY WITH
SEVERAL MODELS IN ROUGH AGREEMENT NOW SHOWING A TROUGH PUSHING DOWN
THE RIDGE WITH THE ATTENDANT COLD FRONT BRINGING RAIN TO THE COAST
BY 12Z/5AM TUESDAY. THE LACK OF SIGNIFICANT AMPLITUDE IN THE
DOWNSTREAM H500 PATTERN IMPLIES THERE IS NOT MUCH COLD AIR TO OUR
EAST TO SLOW THE MOVEMENT OF THE RIDGE. THE PARENT LOW CENTER OF
THIS TROUGH WILL REMAIN ENTRENCHED IN THE GULF OF ALASKA AND QUICKLY
SWING THE COLD FRONT AND TROUGH AXIS ACROSS THE AREA. SNOW LEVELS
AHEAD OF THE FRONT ON TUESDAY WILL STAY ABOVE 8000 FEET AND ONLY
DROP TOWARD 6000 FEET OR SO JUST AHEAD OF THE FRONT. THEY DO DROP
SIGNIFICANTLY TO AROUND 3500 FEET BEHIND THE FRONT BUT THERE WILL BE
LITTLE THREAT FOR SIGNIFICANT CASCADE SNOW ACCUMULATION FROM THE
OVERALL DRIER AIR MASS. /JBONK

.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...SOME SHOWERS MAY
LINGER EARLY TUESDAY NIGHT BEHIND THE COLD FRONT BUT THESE WILL BE
CONFINED MOSTLY TO THE CASCADES BEFORE COMING TO AN END BY EARLY
WEDNESDAY. THE WEATHER PATTERN WEDNESDAY THROUGH FRIDAY WILL BE
MARKED BY A MEAN RIDGE OVER THE CENTRAL CONUS WITH A MEAN TROUGH
MOVING INTO THE WEST. IN GENERAL...THIS WILL LEAD TO A MORE
PROGRESSIVE PATTERN BUT SIGNIFICANT VARIATION AMONG OPERATIONAL
FORECAST MODELS...AND THEIR ENSEMBLE MEMBERS...KEEPS THE CONFIDENCE
IN THE PARTICULARS OF THE FORECAST BELOW NORMAL FOR THE SECOND HALF
OF NEXT WEEK. MADE SOME SLIGHT CHANGES TO POPS...DRYING OUT THE
COAST AND VALLEYS FOR WEDNESDAY BUT MAINTAINING CHANCE POPS THURSDAY
AND FRIDAY. SLIGHTLY INCREASED POPS THURSDAY NIGHT AS THE GEFS MEAN
AND ECMWF QPF FORECASTS SEEM TO SUPPORT ENHANCED SHOWER
ACTIVITY...THOUGH PERHAPS FOR DIFFERENT REASONS /TIMING OF SHORTWAVE
VS. FRONTAL PASSAGE/. NONETHELESS...THE TIMING OF SHORTWAVES AND
WHEN THE UPPER TROUGH SHIFTS INLAND STILL CREATE SOME CONSIDERABLE
UNCERTAINTY IN THE EXTENDED FORECAST PERIOD. TEMPERATURES GENERALLY
TREND NEAR OR SLIGHTLY BELOW SEASONAL NORMALS THROUGH THE SECOND
HALF OF NEXT WEEK.   CULLEN

&&

.AVIATION...COOL UNSETTLED PATTERN CONTINUES. SHOWERS DECREASING
THIS EVENING...THEN SHOULD BE DRY AS AREA WILL BE BETWEEN SYSTEMS.
WITH CLEARING SKIES THIS EVENING...AND COOL AIR MASS WITH WET
GROUND...WILL SEE PATCHY OR AREAS OF FOG AND IFR STRATUS FORM
LATER TONIGHT. NEXT FRONT OFFSHORE WILL ARRIVE LATER SUN...WITH
INCREASING MID AND HIGH CLOUDS LATE TONIGHT INTO SUN AM.

KPDX AND APPROACHES...SCATTERED TO BROKEN VFR CLOUDS INTO EARLY
THIS EVENING...ALONG WITH AN ISOLATED SHOWER OR TWO. SKIES WILL
CLEAR THIS EVENING...WITH AREAS OF FOG/LOW STRATUS FORMING AROUND
THE OPS AREA AFT 08Z...ESPECIALLY TO W AND N OF KPDX. WILL HAVE
OCCASIONAL IFR CLOUDS INTO SUN AM...BUT NOT CONFIDENT YET ON HOW
LONG THESE PERSIST DUE TO INCREASING MID/HIGH CLOUDS VERY LATE
TONIGHT AND SUN AM.                                    ROCKEY.
&&

.MARINE...NOT A LOT OF CHANGE. W TO NW WINDS UNDER 15 KT WITH
SEAS 5 TO 7 FT TONIGHT.

A WARM FRONT IS THEN EXPECTED TO MOVE N ACROSS THE WATERS SUN.
WILL HAVE PERIOD OF GUSTY S WINDS SUN AFTERNOON INTO THE EVENING
AS THE WARM FRONT LIFTS N AND COLD FRONT APPROACHES. NOT ALL THAT
IMPRESSIVE...BUT ENOUGH TO POP GUSTS TO 25 KT. WILL ISSUE SMALL
CRAFT ADVISORY ON ALL WATERS FOR SUN AFTERNOON/EVENING. SEAS WILL
PUSH BACK UP A BIT...BUT REMAIN BELOW 10 FT.

ANOTHER BREAK IS EXPECTED ON MON BEFORE THE NEXT FRONT ARRIVES MON
NIGHT OR TUE. FRONT DOES NOT CURRENTLY LOOK ALL THAT IMPRESSIVE
IN THE FCST MODELS...BUT ANOTHER ROUND OF LOW END SMALL CRAFT
ADVISORY WINDS IS CURRENTLY BEING ADVERTISED. FCST CONFIDENCE
DECREASES FOR THE LATTER HALF OF NEXT WEEK...BUT NO MAJOR WEATHER
SYSTEMS ARE CURRENTLY EXPECTED.                     ROCKPYLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS ON ALL WATERS FOR SUN AFTERNOON
        THROUGH SUN EVENING.

&&

$$

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 252135
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
234 PM PDT SAT APR 25 2015

.SYNOPSIS...THE UPPER LOW WILL CONTINUE WEAKENING AND MOVE EAST BY
EARLY THIS EVENING AS BUILDING HIGH PRESSURE BRINGS A SWIFT END TO
ANY LINGERING SHOWERS. A WARM FRONT WILL MAINLY CLIP THE NORTHERN
COASTAL AREAS WITH SOME LIGHT RAIN SUNDAY. MONDAY WILL BE DRIER AND
MUCH WARMER AS A STRONG UPPER LEVEL RIDGE BUILDS IN FROM THE SOUTH.
THE NEXT COLD FRONT LOOKS TO BRING RAIN EARLY TUESDAY FOLLOWED BY
AFTERNOON SHOWERS. MORE SHOWERS ARE POSSIBLE FOR THE REST OF THE
WEEK AS ANOTHER UPPER LEVEL TROUGH SETTLES NEAR THE PACIFIC
NORTHWEST.

&&

.SHORT TERM...TONIGHT THROUGH TUESDAY...CONVECTION HAS BEEN LESS
THAN STELLAR IN STRENGTH THUS FAR TODAY. COVERAGE HAS MET
EXPECTATIONS THOUGH WITH SOME SHOWERS OVER THE SOUTH VALLEY
PRODUCING A QUICK TENTH OR TWO OF RAIN OVER THE LAST COUPLE HOURS.
AM NOT READY TO COMPLETELY GIVE UP ON A THUNDER THREAT FOR THE NEXT
FEW HOURS BUT HAVE CERTAINLY LOST MOST OF THE EXCITEMENT BUILT OVER
THE LAST COUPLE DAYS. WATER VAPOR IMAGERY IS SHOWING THE LEADING
UPPER EDGE OF THE ENCROACHING WARM FRONT ABOUT TO CROSS THE MOUTH OF
THE COLUMBIA. THIS IS FURTHER INDICATION THAT MID LEVEL SUBSIDENCE
IS BECOMING DOMINANT. AS SUCH...STILL EXPECT SHOWERS WILL QUICKLY
DIMINISH THIS AFTERNOON. FOR ADDED CONFIDENCE...THE SPC STORM SCALE
ENSEMBLE OF OPPORTUNITY MEMBERS BACK THIS NOTION UP AND GENERALLY
CEASE ALL SHOWERS EVEN OVER THE CASCADES BY ABOUT 8 PM.

THE CLOUDS ASSOCIATED WITH THE APPROACHING WARM FRONT APPEAR TO STAY
OFFSHORE ENOUGH TO GIVE DECENT CLEARING FOR A LARGE PART OF THE LATE
EVENING AND OVERNIGHT HOURS. THEREFORE ADDED SOME PATCHY FOG ACROSS
THE REST OF THE LOWER ELEVATIONS AND INCLUDING THE COAST. FORECASTED
TEMPERATURES FOR TONIGHT WERE ALREADY CLOSE TO THE DEW POINTS SO
DIDN`T SEE A NEED TO LOWER THE LOWS.

SUNDAY WILL STAY DRY FOR THE BULK OF THE CWA AS MODELS CONTINUE TO
SHUNT THE APPROACHING WARM FRONT EVER SO GRADUALLY FURTHER NORTH.
STILL MAINTAINED AROUND A 30 PCT POP FOR THE COAST RANGE DURING THE
AFTERNOON AND ABOUT A 60 PCT FOR THE NORTH COAST SUNDAY EVENING BUT
FEEL LIKE THIS IS A CASE WHERE ITS BETTER TO SAY THERE IS A 70 PCT
AND 40 PCT CHANCE RESPECTIVELY IT WILL NOT RAIN TOMORROW. WOULD NOT
BE SURPRISED IF FOLLOWING SHIFTS LOWER POPS YET FURTHER BASED ON
LATER MODEL RUNS. CLEARING SKIES WILL AGAIN ALLOW FOR SOME FOG
DEVELOPMENT LATE OVERNIGHT SUNDAY AND INTO EARLY MONDAY DAYLIGHT
HOURS.

THE UPPER RIDGE OVER THE REGION WILL BE FAIRLY TRANSITORY WITH
SEVERAL MODELS IN ROUGH AGREEMENT NOW SHOWING A TROUGH PUSHING DOWN
THE RIDGE WITH THE ATTENDANT COLD FRONT BRINGING RAIN TO THE COAST
BY 12Z/5AM TUESDAY. THE LACK OF SIGNIFICANT AMPLITUDE IN THE
DOWNSTREAM H500 PATTERN IMPLIES THERE IS NOT MUCH COLD AIR TO OUR
EAST TO SLOW THE MOVEMENT OF THE RIDGE. THE PARENT LOW CENTER OF
THIS TROUGH WILL REMAIN ENTRENCHED IN THE GULF OF ALASKA AND QUICKLY
SWING THE COLD FRONT AND TROUGH AXIS ACROSS THE AREA. SNOW LEVELS
AHEAD OF THE FRONT ON TUESDAY WILL STAY ABOVE 8000 FEET AND ONLY
DROP TOWARD 6000 FEET OR SO JUST AHEAD OF THE FRONT. THEY DO DROP
SIGNIFICANTLY TO AROUND 3500 FEET BEHIND THE FRONT BUT THERE WILL BE
LITTLE THREAT FOR SIGNIFICANT CASCADE SNOW ACCUMULATION FROM THE
OVERALL DRIER AIR MASS. /JBONK

.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...SOME SHOWERS MAY
LINGER EARLY TUESDAY NIGHT BEHIND THE COLD FRONT BUT THESE WILL BE
CONFINED MOSTLY TO THE CASCADES BEFORE COMING TO AN END BY EARLY
WEDNESDAY. THE WEATHER PATTERN WEDNESDAY THROUGH FRIDAY WILL BE
MARKED BY A MEAN RIDGE OVER THE CENTRAL CONUS WITH A MEAN TROUGH
MOVING INTO THE WEST. IN GENERAL...THIS WILL LEAD TO A MORE
PROGRESSIVE PATTERN BUT SIGNIFICANT VARIATION AMONG OPERATIONAL
FORECAST MODELS...AND THEIR ENSEMBLE MEMBERS...KEEPS THE CONFIDENCE
IN THE PARTICULARS OF THE FORECAST BELOW NORMAL FOR THE SECOND HALF
OF NEXT WEEK. MADE SOME SLIGHT CHANGES TO POPS...DRYING OUT THE
COAST AND VALLEYS FOR WEDNESDAY BUT MAINTAINING CHANCE POPS THURSDAY
AND FRIDAY. SLIGHTLY INCREASED POPS THURSDAY NIGHT AS THE GEFS MEAN
AND ECMWF QPF FORECASTS SEEM TO SUPPORT ENHANCED SHOWER
ACTIVITY...THOUGH PERHAPS FOR DIFFERENT REASONS /TIMING OF SHORTWAVE
VS. FRONTAL PASSAGE/. NONETHELESS...THE TIMING OF SHORTWAVES AND
WHEN THE UPPER TROUGH SHIFTS INLAND STILL CREATE SOME CONSIDERABLE
UNCERTAINTY IN THE EXTENDED FORECAST PERIOD. TEMPERATURES GENERALLY
TREND NEAR OR SLIGHTLY BELOW SEASONAL NORMALS THROUGH THE SECOND
HALF OF NEXT WEEK.   CULLEN

&&

.AVIATION...COOL UNSETTLED PATTERN CONTINUES. SHOWERS DECREASING
THIS EVENING...THEN SHOULD BE DRY AS AREA WILL BE BETWEEN SYSTEMS.
WITH CLEARING SKIES THIS EVENING...AND COOL AIR MASS WITH WET
GROUND...WILL SEE PATCHY OR AREAS OF FOG AND IFR STRATUS FORM
LATER TONIGHT. NEXT FRONT OFFSHORE WILL ARRIVE LATER SUN...WITH
INCREASING MID AND HIGH CLOUDS LATE TONIGHT INTO SUN AM.

KPDX AND APPROACHES...SCATTERED TO BROKEN VFR CLOUDS INTO EARLY
THIS EVENING...ALONG WITH AN ISOLATED SHOWER OR TWO. SKIES WILL
CLEAR THIS EVENING...WITH AREAS OF FOG/LOW STRATUS FORMING AROUND
THE OPS AREA AFT 08Z...ESPECIALLY TO W AND N OF KPDX. WILL HAVE
OCCASIONAL IFR CLOUDS INTO SUN AM...BUT NOT CONFIDENT YET ON HOW
LONG THESE PERSIST DUE TO INCREASING MID/HIGH CLOUDS VERY LATE
TONIGHT AND SUN AM.                                    ROCKEY.
&&

.MARINE...NOT A LOT OF CHANGE. W TO NW WINDS UNDER 15 KT WITH
SEAS 5 TO 7 FT TONIGHT.

A WARM FRONT IS THEN EXPECTED TO MOVE N ACROSS THE WATERS SUN.
WILL HAVE PERIOD OF GUSTY S WINDS SUN AFTERNOON INTO THE EVENING
AS THE WARM FRONT LIFTS N AND COLD FRONT APPROACHES. NOT ALL THAT
IMPRESSIVE...BUT ENOUGH TO POP GUSTS TO 25 KT. WILL ISSUE SMALL
CRAFT ADVISORY ON ALL WATERS FOR SUN AFTERNOON/EVENING. SEAS WILL
PUSH BACK UP A BIT...BUT REMAIN BELOW 10 FT.

ANOTHER BREAK IS EXPECTED ON MON BEFORE THE NEXT FRONT ARRIVES MON
NIGHT OR TUE. FRONT DOES NOT CURRENTLY LOOK ALL THAT IMPRESSIVE
IN THE FCST MODELS...BUT ANOTHER ROUND OF LOW END SMALL CRAFT
ADVISORY WINDS IS CURRENTLY BEING ADVERTISED. FCST CONFIDENCE
DECREASES FOR THE LATTER HALF OF NEXT WEEK...BUT NO MAJOR WEATHER
SYSTEMS ARE CURRENTLY EXPECTED.                     ROCKPYLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS ON ALL WATERS FOR SUN AFTERNOON
        THROUGH SUN EVENING.

&&

$$

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 251619
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
919 AM PDT SAT APR 25 2015

.SYNOPSIS...UPPER LEVEL LOW PRESSURE CONTINUES TO BRING COOL AND
UNSETTLED WEATHER TO THE PACIFIC NORTHWEST. EXPECT SHOWERS TO
CONTINUE TODAY WITH A SNOW LEVEL OF 3000 TO 4000 FEET. ANY HEAVIER
SHOWERS MAY PRODUCE SMALL HAIL AND LIGHTNING...ESPECIALLY EARLY THIS
AFTERNOON. THE UPPER LOW WILL WEAKEN AND MOVE EAST BY EARLY THIS
EVENING...WITH HIGH PRESSURE BRINGING A SWIFT END TO ANY LINGERING
SHOWERS. A WARM FRONT MAY CLIP THE REGION WITH SOME LIGHT RAIN
SUNDAY AND SUNDAY NIGHT...MOSTLY ALONG THE NORTH COAST. MONDAY WILL
BE DRIER AND MUCH WARMER AS A STRONG UPPER LEVEL RIDGE BUILDS IN
FROM THE SOUTH. THE NEXT COLD FRONT MAY BRING MORE SHOWERS AS EARLY
AS TUESDAY...WITH MORE SHOWERS POSSIBLE FOR THE REST OF THE WEEK AS
ANOTHER UPPER LEVEL TROUGH SETTLES NEAR THE PACIFIC NORTHWEST.

&&

.UPDATE...OVERALL FORECAST REMAINS ON TRACK FOR THE MORNING UPDATE
PACKAGE. THERE WAS SOME PATCHY VALLEY AND COASTAL FOG SO ADDED THAT
IN FOR THE MORNING. SHOULD BE FAIRLY SHORT LIVED AS ITS MAINLY
GROUND FOG AND IT WILL NOT TAKE MUCH HEATING TO GET IT TO DISSIPATE.
WAS DEBATING WHETHER TO COVERT THE THUNDERSTORM MENTION OVER TO A
COVERAGE WORDING BUT THE 12Z NAM AND GFS RUNS ARE IN AND ARE SHOWING
LESS COOLING ALOFT AS THE FINAL COLD AIR LOBE ROTATES ACROSS THE
REGION. DECIDED TO STICK WITH THE UNCERTAINTY SIDE AS SOME SHALLOW
CUMULUS IS ALREADY STARTING TO BUILD OVER PARTS OF THE COAST RANGE
WHICH HAVE CLEARED EARLIER. SIMILAR TO YESTERDAY...COULD GET A RAPID
UPDRAFT TO BUILD WITH THOSE SUN BREAKS AND ESPECIALLY AS VALLEY
INVERSIONS BREAK THIS MORNING. THE UPDRAFTS WILL ALSO GET A BIT OF
LIFT ENHANCEMENT AS THE 100 KT JET SLIDES OVER THE TOP OF US AROUND
MID-DAY. THOSE QUICK UPDRAFTS MIGHT GET JUST ENOUGH CLOUD CHARGE
SEPARATION TO PRODUCT A FEW ONE OR TWO RUMBLE WONDERS. THOSE
LIGHTNING DISCHARGES WOULD MOST LIKELY STAY IN CLOUD BUT CANNOT
COMPLETELY RULE OUT A CLOUD TO GROUND STRIKE EITHER. ALSO DECIDED TO
PULL OUT ANY MENTION OF THUNDER FOR THE EARLY EVENING AS MID LEVEL
SUBSIDENCE WILL RAPIDLY SQUASH ANY THREAT OF DEEP CONVECTION AND
ALSO BELIEVE THE LOW LEVEL INSTABILITY WILL HAVE BEEN WELL TURNED
OVER AND MIXED BY ABOUT 6 PM TODAY.

UPDATES HAVE ALREADY BEEN SENT. /JBONK

&&

.AVIATION...A SHOWERY PATTERN TO CONTINUE THROUGH THIS AFTERNOON AS
A COLD UPPER LEVEL TROUGH GRADUALLY MOVES INLAND. EXPECT PRIMARILY
VFR CONDITIONS TO PERSIST...WITH PERIODIC BRIEF MVFR CIGS DURING
HEAVIER SHOWERS. PATCHY IFR STRATUS AND FOG IN RIVER VALLEYS AND
BAYS UNTIL 17Z. WHILE THERE IS A CHANCE FOR ISOLATED THUNDERSTORMS
AND SMALL HAIL...CONFIDENCE IN LOCATION AND TIMING IS NOT HIGH
ENOUGH TO INCLUDE IN TAFS. AS THE TROUGH PUSHES FURTHER EAST AND
HIGH PRES BUILDS IN BEHIND...SHOWERS WILL BEGIN TO TAPER OFF ALONG
THE COAST AFTER 22Z...AND OVER THE INTERIOR AFTER 00Z. HIGH PRES
STRENGTHENS TONIGHT INTO SUN AM...ALLOWING PATCHY FOG/STRATUS TO
FORM LATE TONIGHT.

KPDX AND APPROACHES...POCKETS OF IFR STRATUS AROUND OPS AREA
UNTIL17Z THIS AM...MAINLY TO N AND E OF KPDX. OVERALL...WILL SEE VFR
WITH SCATTERED SHOWERS AND OCCASIONAL MVFR UNDER SHOWERS. WILL KEEP
A LESS THAN 20 PERCENT CHANCE OF A THUNDERSTORM IN AREA BETWEEN 19Z
TO 02Z...BUT IF DOES MORE LIKELY TO BE EAST OF OPS AREAS OVER
CASCADES OR FOOTHILLS. ROCKEY.

&&

.MARINE...NOT A LOT OF CHANGE. COOL UNSTABLE AIR MASS OVER THE
COASTAL WATERS TODAY...WITH WINDS REMAINING UNDER 15 KT. THOUGH
COULD SEE A FEW GUSTS TO 20 KT AROUND SHOWERS. SEAS HOLDING AT 5 TO
7 FT.

A WARM FRONT IS THEN EXPECTED TO MOVE N ACROSS THE WATERS SUN. THE
LATEST COMPUTER RUNS HAVE TRENDED A LITTLE STRONGER WITH THE
WINDS...INDICATING THAT A PERIOD OF SMALL CRAFT ADVISORY SOUTHERLY
WINDS ARE LIKELY ON SUN ESPECIALLY OVER THE OUTER WATERS. SEAS
SHOULD ALSO INCREASE A BIT IN RESPONSE TO THE WINDS...BUT ARE
CURRENTLY EXPECTED TO REMAIN BELOW 10 FT.

ANOTHER BREAK IS EXPECTED ON MON BEFORE THE NEXT FRONT ARRIVES MON
NIGHT OR TUE. FRONT DOES NOT CURRENTLY LOOK ALL THAT IMPRESSIVE IN
THE FCST MODELS...BUT ANOTHER ROUND OF LOW END SMALL CRAFT ADVISORY
WINDS IS CURRENTLY BEING ADVERTISED. FCST CONFIDENCE DECREASES FOR
THE LATTER HALF OF NEXT WEEK...BUT NO MAJOR WEATHER SYSTEMS ARE
CURRENTLY EXPECTED.                     ROCKPYLE

&&

.PREV DISCUSSION... /ISSUED 326 AM PDT SAT APR 25 2015/

SHORT TERM...TODAY THROUGH MONDAY...NWS DOPPLER RADAR CONTINUES TO
SHOW SEVERAL SHOWERS MOVING ACROSS SW WASHINGTON AND NW OREGON THIS
MORNING...AS THE AIR MASS REMAINS COOL...MOIST AND UNSTABLE DUE TO AN
UPPER LEVEL LOW CENTERED OVER VANCOUVER ISLAND. ONE LAST LOBE OF COOL
AIR ALOFT IS EXPECTED TO PIVOT ACROSS THE FORECAST AREA AROUND MIDDAY
TODAY...COMBINING WITH OCCASIONAL SUNSHINE TO PRODUCE ANOTHER SPIKE
IN SHOWER ACTIVITY THIS MORNING INTO MID AFTERNOON.

WITH 500 MB TEMPS AROUND -30 DEG C WITHIN THE COOL CORE ALOFT...THE
POTENTIAL EXISTS FOR SOMEWHAT DEEPER CONVECTION THAN FRIDAY. A FEW
STRAY CLAPS OF THUNDER WERE REPORTED FRIDAY...EVEN WITH MILDER AIR
ALOFT. THEREFORE THE POTENTIAL EXISTS FOR ISOLATED THUNDERSTORMS
TODAY...ESPECIALLY NORTH OF SALEM. WITH FREEZING LEVELS HOVERING IN
THE 4000-5000 FT RANGE...HEAVIER SHOWERS SHOULD ALSO HAVE AN EASY
TIME PRODUCING SMALL HAIL. SHEAR PROFILES LOOK WEAK AND CAPE IS
MINIMAL...SO WE DO NOT EXPECT ANYTHING TO APPROACH SEVERE LIMITS.

THE CASCADES HAVE ALREADY RECEIVED A FEW INCHES OF SNOW...WITH AS
MUCH AS 6-8 INCHES BEING REPORTED AT TIMBERLINE SINCE THURSDAY. A
COUPLE MORE INCHES COULD ACCUMULATE FROM SNOW SHOWERS TODAY...BUT
ACCUMULATIONS WILL BE SPOTTY. SOME WET SNOW IS EXPECTED AT PASS
LEVEL...THOUGH THE STRONG APRIL SUN WILL PROBABLY MELT MOST SNOW OFF
THE ROADS BY MID-MORNING.

INSTABILITY WILL COME TO A QUICK END FROM TOP TO BOTTOM LATER THIS
AFTERNOON AND EVENING...AS TEMPS WARM ALOFT AND COOL AT THE SURFACE
WITH THE LOSS OF SOLAR HEATING. MEANWHILE HIGH PRESSURE WILL BUILD
ACROSS SW WA/NW OR...BRINGING SUBSIDENCE. THIS SHOULD BRING A SWIFT
END TO ANY LINGERING SHOWERS THIS EVENING. SOME VALLEY FOG IS
POSSIBLE IF SKIES STAY CLEAR TONIGHT...BUT HIGH CLOUDS AHEAD OF AN
APPROACHING WARM FRONT WILL PROBABLY MAKE IT DIFFICULT FOR FOG TO
BECOME TOO WIDESPREAD TONIGHT AND SUNDAY MORNING.

MODELS ARE FINALLY SHOWING SOME AGREEMENT THAT THE WARM FRONT WILL
BRUSH THE NORTH COAST WITH SOME RAIN WHILE MUCH OF THE WILLAMETTE
VALLEY AND OREGON CASCADES REMAIN DRY. MUCH WARMER AIR BEHIND THE
FRONT WILL CAUSE A SHARP INCREASE IN TEMPS MONDAY. WITH 850 MB TEMPS
FCST TO BE IN THE +12 TO +14 DEG C RANGE...TEMPS INLAND COULD PUSH 80
DEGREES IN THE VALLEYS.  WEAGLE

LONG TERM...MONDAY NIGHT THROUGH FRIDAY...MODELS CONTINUE TO
STRUGGLE WITH THE DETAILS TUESDAY AND BEYOND...THOUGH THEY ARE COMING
INTO BETTER AGREEMENT WITH THE GENERAL IDEA OF PUSHING THE MEAN RIDGE
POSITION EASTWARD INTO THE ROCKIES. THIS WOULD OPEN THE DOOR FOR MORE
UNSETTLED WEATHER BEGINNING WITH THE COLD FRONT TUESDAY AND
CONTINUING FOR THE REMAINDER OF THE WEEK AS A LONGWAVE UPPER TROUGH
PARKS OVER THE PAC NW. THERE REMAINS GREAT VARIATION BETWEEN
OPERATIONAL MODELS AND THEIR ENSEMBLE MEMBERS AS TO WHEN INDIVIDUAL
DISTURBANCES WOULD BRING CHANCES FOR RAIN. INCREASED POPS A BIT
CONSIDERING THE PERSISTENT LONGWAVE TROUGH...BUT HELD THEM NEAR CLIMO
DUE TO THE TIMING UNCERTAINTY. TEMPS SHOULD COOL BACK DOWN TO WITHIN
A FEW DEGREES OF NORMAL MIDWEEK...PERHAPS TRENDING BACK BELOW NORMAL
TOWARD THE END OF THE WEEK.  WEAGLE

&&

.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 251619
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
919 AM PDT SAT APR 25 2015

.SYNOPSIS...UPPER LEVEL LOW PRESSURE CONTINUES TO BRING COOL AND
UNSETTLED WEATHER TO THE PACIFIC NORTHWEST. EXPECT SHOWERS TO
CONTINUE TODAY WITH A SNOW LEVEL OF 3000 TO 4000 FEET. ANY HEAVIER
SHOWERS MAY PRODUCE SMALL HAIL AND LIGHTNING...ESPECIALLY EARLY THIS
AFTERNOON. THE UPPER LOW WILL WEAKEN AND MOVE EAST BY EARLY THIS
EVENING...WITH HIGH PRESSURE BRINGING A SWIFT END TO ANY LINGERING
SHOWERS. A WARM FRONT MAY CLIP THE REGION WITH SOME LIGHT RAIN
SUNDAY AND SUNDAY NIGHT...MOSTLY ALONG THE NORTH COAST. MONDAY WILL
BE DRIER AND MUCH WARMER AS A STRONG UPPER LEVEL RIDGE BUILDS IN
FROM THE SOUTH. THE NEXT COLD FRONT MAY BRING MORE SHOWERS AS EARLY
AS TUESDAY...WITH MORE SHOWERS POSSIBLE FOR THE REST OF THE WEEK AS
ANOTHER UPPER LEVEL TROUGH SETTLES NEAR THE PACIFIC NORTHWEST.

&&

.UPDATE...OVERALL FORECAST REMAINS ON TRACK FOR THE MORNING UPDATE
PACKAGE. THERE WAS SOME PATCHY VALLEY AND COASTAL FOG SO ADDED THAT
IN FOR THE MORNING. SHOULD BE FAIRLY SHORT LIVED AS ITS MAINLY
GROUND FOG AND IT WILL NOT TAKE MUCH HEATING TO GET IT TO DISSIPATE.
WAS DEBATING WHETHER TO COVERT THE THUNDERSTORM MENTION OVER TO A
COVERAGE WORDING BUT THE 12Z NAM AND GFS RUNS ARE IN AND ARE SHOWING
LESS COOLING ALOFT AS THE FINAL COLD AIR LOBE ROTATES ACROSS THE
REGION. DECIDED TO STICK WITH THE UNCERTAINTY SIDE AS SOME SHALLOW
CUMULUS IS ALREADY STARTING TO BUILD OVER PARTS OF THE COAST RANGE
WHICH HAVE CLEARED EARLIER. SIMILAR TO YESTERDAY...COULD GET A RAPID
UPDRAFT TO BUILD WITH THOSE SUN BREAKS AND ESPECIALLY AS VALLEY
INVERSIONS BREAK THIS MORNING. THE UPDRAFTS WILL ALSO GET A BIT OF
LIFT ENHANCEMENT AS THE 100 KT JET SLIDES OVER THE TOP OF US AROUND
MID-DAY. THOSE QUICK UPDRAFTS MIGHT GET JUST ENOUGH CLOUD CHARGE
SEPARATION TO PRODUCT A FEW ONE OR TWO RUMBLE WONDERS. THOSE
LIGHTNING DISCHARGES WOULD MOST LIKELY STAY IN CLOUD BUT CANNOT
COMPLETELY RULE OUT A CLOUD TO GROUND STRIKE EITHER. ALSO DECIDED TO
PULL OUT ANY MENTION OF THUNDER FOR THE EARLY EVENING AS MID LEVEL
SUBSIDENCE WILL RAPIDLY SQUASH ANY THREAT OF DEEP CONVECTION AND
ALSO BELIEVE THE LOW LEVEL INSTABILITY WILL HAVE BEEN WELL TURNED
OVER AND MIXED BY ABOUT 6 PM TODAY.

UPDATES HAVE ALREADY BEEN SENT. /JBONK

&&

.AVIATION...A SHOWERY PATTERN TO CONTINUE THROUGH THIS AFTERNOON AS
A COLD UPPER LEVEL TROUGH GRADUALLY MOVES INLAND. EXPECT PRIMARILY
VFR CONDITIONS TO PERSIST...WITH PERIODIC BRIEF MVFR CIGS DURING
HEAVIER SHOWERS. PATCHY IFR STRATUS AND FOG IN RIVER VALLEYS AND
BAYS UNTIL 17Z. WHILE THERE IS A CHANCE FOR ISOLATED THUNDERSTORMS
AND SMALL HAIL...CONFIDENCE IN LOCATION AND TIMING IS NOT HIGH
ENOUGH TO INCLUDE IN TAFS. AS THE TROUGH PUSHES FURTHER EAST AND
HIGH PRES BUILDS IN BEHIND...SHOWERS WILL BEGIN TO TAPER OFF ALONG
THE COAST AFTER 22Z...AND OVER THE INTERIOR AFTER 00Z. HIGH PRES
STRENGTHENS TONIGHT INTO SUN AM...ALLOWING PATCHY FOG/STRATUS TO
FORM LATE TONIGHT.

KPDX AND APPROACHES...POCKETS OF IFR STRATUS AROUND OPS AREA
UNTIL17Z THIS AM...MAINLY TO N AND E OF KPDX. OVERALL...WILL SEE VFR
WITH SCATTERED SHOWERS AND OCCASIONAL MVFR UNDER SHOWERS. WILL KEEP
A LESS THAN 20 PERCENT CHANCE OF A THUNDERSTORM IN AREA BETWEEN 19Z
TO 02Z...BUT IF DOES MORE LIKELY TO BE EAST OF OPS AREAS OVER
CASCADES OR FOOTHILLS. ROCKEY.

&&

.MARINE...NOT A LOT OF CHANGE. COOL UNSTABLE AIR MASS OVER THE
COASTAL WATERS TODAY...WITH WINDS REMAINING UNDER 15 KT. THOUGH
COULD SEE A FEW GUSTS TO 20 KT AROUND SHOWERS. SEAS HOLDING AT 5 TO
7 FT.

A WARM FRONT IS THEN EXPECTED TO MOVE N ACROSS THE WATERS SUN. THE
LATEST COMPUTER RUNS HAVE TRENDED A LITTLE STRONGER WITH THE
WINDS...INDICATING THAT A PERIOD OF SMALL CRAFT ADVISORY SOUTHERLY
WINDS ARE LIKELY ON SUN ESPECIALLY OVER THE OUTER WATERS. SEAS
SHOULD ALSO INCREASE A BIT IN RESPONSE TO THE WINDS...BUT ARE
CURRENTLY EXPECTED TO REMAIN BELOW 10 FT.

ANOTHER BREAK IS EXPECTED ON MON BEFORE THE NEXT FRONT ARRIVES MON
NIGHT OR TUE. FRONT DOES NOT CURRENTLY LOOK ALL THAT IMPRESSIVE IN
THE FCST MODELS...BUT ANOTHER ROUND OF LOW END SMALL CRAFT ADVISORY
WINDS IS CURRENTLY BEING ADVERTISED. FCST CONFIDENCE DECREASES FOR
THE LATTER HALF OF NEXT WEEK...BUT NO MAJOR WEATHER SYSTEMS ARE
CURRENTLY EXPECTED.                     ROCKPYLE

&&

.PREV DISCUSSION... /ISSUED 326 AM PDT SAT APR 25 2015/

SHORT TERM...TODAY THROUGH MONDAY...NWS DOPPLER RADAR CONTINUES TO
SHOW SEVERAL SHOWERS MOVING ACROSS SW WASHINGTON AND NW OREGON THIS
MORNING...AS THE AIR MASS REMAINS COOL...MOIST AND UNSTABLE DUE TO AN
UPPER LEVEL LOW CENTERED OVER VANCOUVER ISLAND. ONE LAST LOBE OF COOL
AIR ALOFT IS EXPECTED TO PIVOT ACROSS THE FORECAST AREA AROUND MIDDAY
TODAY...COMBINING WITH OCCASIONAL SUNSHINE TO PRODUCE ANOTHER SPIKE
IN SHOWER ACTIVITY THIS MORNING INTO MID AFTERNOON.

WITH 500 MB TEMPS AROUND -30 DEG C WITHIN THE COOL CORE ALOFT...THE
POTENTIAL EXISTS FOR SOMEWHAT DEEPER CONVECTION THAN FRIDAY. A FEW
STRAY CLAPS OF THUNDER WERE REPORTED FRIDAY...EVEN WITH MILDER AIR
ALOFT. THEREFORE THE POTENTIAL EXISTS FOR ISOLATED THUNDERSTORMS
TODAY...ESPECIALLY NORTH OF SALEM. WITH FREEZING LEVELS HOVERING IN
THE 4000-5000 FT RANGE...HEAVIER SHOWERS SHOULD ALSO HAVE AN EASY
TIME PRODUCING SMALL HAIL. SHEAR PROFILES LOOK WEAK AND CAPE IS
MINIMAL...SO WE DO NOT EXPECT ANYTHING TO APPROACH SEVERE LIMITS.

THE CASCADES HAVE ALREADY RECEIVED A FEW INCHES OF SNOW...WITH AS
MUCH AS 6-8 INCHES BEING REPORTED AT TIMBERLINE SINCE THURSDAY. A
COUPLE MORE INCHES COULD ACCUMULATE FROM SNOW SHOWERS TODAY...BUT
ACCUMULATIONS WILL BE SPOTTY. SOME WET SNOW IS EXPECTED AT PASS
LEVEL...THOUGH THE STRONG APRIL SUN WILL PROBABLY MELT MOST SNOW OFF
THE ROADS BY MID-MORNING.

INSTABILITY WILL COME TO A QUICK END FROM TOP TO BOTTOM LATER THIS
AFTERNOON AND EVENING...AS TEMPS WARM ALOFT AND COOL AT THE SURFACE
WITH THE LOSS OF SOLAR HEATING. MEANWHILE HIGH PRESSURE WILL BUILD
ACROSS SW WA/NW OR...BRINGING SUBSIDENCE. THIS SHOULD BRING A SWIFT
END TO ANY LINGERING SHOWERS THIS EVENING. SOME VALLEY FOG IS
POSSIBLE IF SKIES STAY CLEAR TONIGHT...BUT HIGH CLOUDS AHEAD OF AN
APPROACHING WARM FRONT WILL PROBABLY MAKE IT DIFFICULT FOR FOG TO
BECOME TOO WIDESPREAD TONIGHT AND SUNDAY MORNING.

MODELS ARE FINALLY SHOWING SOME AGREEMENT THAT THE WARM FRONT WILL
BRUSH THE NORTH COAST WITH SOME RAIN WHILE MUCH OF THE WILLAMETTE
VALLEY AND OREGON CASCADES REMAIN DRY. MUCH WARMER AIR BEHIND THE
FRONT WILL CAUSE A SHARP INCREASE IN TEMPS MONDAY. WITH 850 MB TEMPS
FCST TO BE IN THE +12 TO +14 DEG C RANGE...TEMPS INLAND COULD PUSH 80
DEGREES IN THE VALLEYS.  WEAGLE

LONG TERM...MONDAY NIGHT THROUGH FRIDAY...MODELS CONTINUE TO
STRUGGLE WITH THE DETAILS TUESDAY AND BEYOND...THOUGH THEY ARE COMING
INTO BETTER AGREEMENT WITH THE GENERAL IDEA OF PUSHING THE MEAN RIDGE
POSITION EASTWARD INTO THE ROCKIES. THIS WOULD OPEN THE DOOR FOR MORE
UNSETTLED WEATHER BEGINNING WITH THE COLD FRONT TUESDAY AND
CONTINUING FOR THE REMAINDER OF THE WEEK AS A LONGWAVE UPPER TROUGH
PARKS OVER THE PAC NW. THERE REMAINS GREAT VARIATION BETWEEN
OPERATIONAL MODELS AND THEIR ENSEMBLE MEMBERS AS TO WHEN INDIVIDUAL
DISTURBANCES WOULD BRING CHANCES FOR RAIN. INCREASED POPS A BIT
CONSIDERING THE PERSISTENT LONGWAVE TROUGH...BUT HELD THEM NEAR CLIMO
DUE TO THE TIMING UNCERTAINTY. TEMPS SHOULD COOL BACK DOWN TO WITHIN
A FEW DEGREES OF NORMAL MIDWEEK...PERHAPS TRENDING BACK BELOW NORMAL
TOWARD THE END OF THE WEEK.  WEAGLE

&&

.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 251027
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
326 AM PDT SAT APR 25 2015

.SYNOPSIS...UPPER LEVEL LOW PRESSURE CONTINUES TO BRING COOL AND
UNSETTLED WEATHER TO THE PACIFIC NORTHWEST. EXPECT VALLEY RAIN AND
MOUNTAIN SNOW SHOWERS TO CONTINUE TODAY. ANY HEAVIER SHOWERS MAY
PRODUCE SMALL HAIL AND LIGHTNING...ESPECIALLY EARLY THIS AFTERNOON.
THE UPPER LOW WILL WEAKEN AND MOVE EAST BY THIS EVENING...WITH HIGH
PRESSURE BRINGING A SWIFT END TO ANY LINGERING SHOWERS. A WARM FRONT
MAY CLIP THE REGION WITH SOME LIGHT RAIN SUNDAY AND SUNDAY NIGHT...
MOSTLY ALONG THE NORTH COAST. MONDAY WILL BE DRIER AND MUCH WARMER AS
A STRONG UPPER LEVEL RIDGE BUILDS IN FROM THE SOUTH. THE NEXT COLD
FRONT MAY BRING MORE SHOWERS AS EARLY AS TUESDAY...WITH MORE SHOWERS
POSSIBLE FOR THE REST OF THE WEEK AS ANOTHER UPPER LEVEL TROUGH
SETTLES NEAR THE PACIFIC NORTHWEST.

&&

.SHORT TERM...TODAY THROUGH MONDAY...NWS DOPPLER RADAR CONTINUES TO
SHOW SEVERAL SHOWERS MOVING ACROSS SW WASHINGTON AND NW OREGON THIS
MORNING...AS THE AIR MASS REMAINS COOL...MOIST AND UNSTABLE DUE TO AN
UPPER LEVEL LOW CENTERED OVER VANCOUVER ISLAND. ONE LAST LOBE OF COOL
AIR ALOFT IS EXPECTED TO PIVOT ACROSS THE FORECAST AREA AROUND MIDDAY
TODAY...COMBINING WITH OCCASIONAL SUNSHINE TO PRODUCE ANOTHER SPIKE
IN SHOWER ACTIVITY THIS MORNING INTO MID AFTERNOON.

WITH 500 MB TEMPS AROUND -30 DEG C WITHIN THE COOL CORE ALOFT...THE
POTENTIAL EXISTS FOR SOMEWHAT DEEPER CONVECTION THAN FRIDAY. A FEW
STRAY CLAPS OF THUNDER WERE REPORTED FRIDAY...EVEN WITH MILDER AIR
ALOFT. THEREFORE THE POTENTIAL EXISTS FOR ISOLATED THUNDERSTORMS
TODAY...ESPECIALLY NORTH OF SALEM. WITH FREEZING LEVELS HOVERING IN
THE 4000-5000 FT RANGE...HEAVIER SHOWERS SHOULD ALSO HAVE AN EASY
TIME PRODUCING SMALL HAIL. SHEAR PROFILES LOOK WEAK AND CAPE IS
MINIMAL...SO WE DO NOT EXPECT ANYTHING TO APPROACH SEVERE LIMITS.

THE CASCADES HAVE ALREADY RECEIVED A FEW INCHES OF SNOW...WITH AS
MUCH AS 6-8 INCHES BEING REPORTED AT TIMBERLINE SINCE THURSDAY. A
COUPLE MORE INCHES COULD ACCUMULATE FROM SNOW SHOWERS TODAY...BUT
ACCUMULATIONS WILL BE SPOTTY. SOME WET SNOW IS EXPECTED AT PASS
LEVEL...THOUGH THE STRONG APRIL SUN WILL PROBABLY MELT MOST SNOW OFF
THE ROADS BY MID-MORNING.

INSTABILITY WILL COME TO A QUICK END FROM TOP TO BOTTOM LATER THIS
AFTERNOON AND EVENING...AS TEMPS WARM ALOFT AND COOL AT THE SURFACE
WITH THE LOSS OF SOLAR HEATING. MEANWHILE HIGH PRESSURE WILL BUILD
ACROSS SW WA/NW OR...BRINGING SUBSIDENCE. THIS SHOULD BRING A SWIFT
END TO ANY LINGERING SHOWERS THIS EVENING. SOME VALLEY FOG IS
POSSIBLE IF SKIES STAY CLEAR TONIGHT...BUT HIGH CLOUDS AHEAD OF AN
APPROACHING WARM FRONT WILL PROBABLY MAKE IT DIFFICULT FOR FOG TO
BECOME TOO WIDESPREAD TONIGHT AND SUNDAY MORNING.

MODELS ARE FINALLY SHOWING SOME AGREEMENT THAT THE WARM FRONT WILL
BRUSH THE NORTH COAST WITH SOME RAIN WHILE MUCH OF THE WILLAMETTE
VALLEY AND OREGON CASCADES REMAIN DRY. MUCH WARMER AIR BEHIND THE
FRONT WILL CAUSE A SHARP INCREASE IN TEMPS MONDAY. WITH 850 MB TEMPS
FCST TO BE IN THE +12 TO +14 DEG C RANGE...TEMPS INLAND COULD PUSH 80
DEGREES IN THE VALLEYS.  WEAGLE

.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...MODELS CONTINUE TO
STRUGGLE WITH THE DETAILS TUESDAY AND BEYOND...THOUGH THEY ARE COMING
INTO BETTER AGREEMENT WITH THE GENERAL IDEA OF PUSHING THE MEAN RIDGE
POSITION EASTWARD INTO THE ROCKIES. THIS WOULD OPEN THE DOOR FOR MORE
UNSETTLED WEATHER BEGINNING WITH THE COLD FRONT TUESDAY AND
CONTINUING FOR THE REMAINDER OF THE WEEK AS A LONGWAVE UPPER TROUGH
PARKS OVER THE PAC NW. THERE REMAINS GREAT VARIATION BETWEEN
OPERATIONAL MODELS AND THEIR ENSEMBLE MEMBERS AS TO WHEN INDIVIDUAL
DISTURBANCES WOULD BRING CHANCES FOR RAIN. INCREASED POPS A BIT
CONSIDERING THE PERSISTENT LONGWAVE TROUGH...BUT HELD THEM NEAR CLIMO
DUE TO THE TIMING UNCERTAINTY. TEMPS SHOULD COOL BACK DOWN TO WITHIN
A FEW DEGREES OF NORMAL MIDWEEK...PERHAPS TRENDING BACK BELOW NORMAL
TOWARD THE END OF THE WEEK.  WEAGLE

&&

.AVIATION...A SHOWERY PATTERN TO CONTINUE THROUGH THIS AFTERNOON
AS A COLD UPPER LEVEL TROUGH GRADUALLY MOVES INLAND. EXPECT
PRIMARILY VFR CONDITIONS TO PERSIST...WITH PERIODIC BRIEF MVFR
CIGS DURING HEAVIER SHOWERS. THERE IS ALSO A CHANCE FOR ISOLATED
THUNDERSTORMS AND SMALL HAIL...BUT CONFIDENCE IN LOCATION AND
TIMING IS NOT HIGH ENOUGH TO INCLUDE IN TAFS. AS THE TROUGH PUSHES
FURTHER EAST AND HIGH PRES BUILDS IN BEHIND...SHOWERS WILL BEGIN
TO TAPER OFF ALONG THE COAST IN THE MID AFTERNOON AND OVER THE
INTERIOR DURING THE LATE AFTERNOON AND EARLY EVENING. HIGH PRES
STRENGTHENS OVERNIGHT SAT INTO SUN MORNING...POSSIBLY ALLOWING PATCHY
FOG MAY TO DEVELOP TOWARD 12Z SUN.

KPDX AND APPROACHES...SHOWERS CHANCES CONTINUE THROUGH THIS
AFTERNOON. EXPECT MAINLY VFR WITH BRIEF PERIODS OF MVFR DURING
HEAVIER SHOWERS. THERE IS A THREAT FOR THUNDERSTORMS AT THE
TERMINAL OR IN THE VICINITY BETWEEN 18Z SAT AND 00Z SUN. PYLE

&&

.MARINE...SEAS HAVE REMAINED A LITTLE HIGHER THAN THE ENP GUIDANCE
WAS SUGGESTING FOR THIS MORNING. THEY ARE CURRENTLY SITTING AT 8
TO 10 FT. EXPECT THEM TO GRADUALLY SUBSIDE THROUGH THE
DAY...EVENTUALLY REACHING 5 FT TONIGHT OR EARLY SUN MORNING.

FAIRLY BENIGN CONDITIONS ARE EXPECTED TODAY AND TONIGHT AS HIGH
PRES MOVES OVER THE WATERS AND THEN PUSHES INLAND. A WARM FRONT
IS THEN EXPECTED TO MOVE INTO THE WATERS SUN MORNING...THEN LIFT
NORTHWARD THROUGH THE DAY. THE LATEST MODEL RUNS HAVE TRENDED A
LITTLE STRONGER WITH THE WINDS...INDICATING THAT A PERIOD OF SMALL
CRAFT ADVISORY SOUTHERLY WINDS ARE LIKELY ON SUN ESPECIALLY OVER
THE OUTER WATERS. SEAS SHOULD ALSO INCREASE A BIT IN RESPONSE TO
THE WINDS...BUT ARE CURRENTLY EXPECTED TO REMAIN BELOW 10 FT.

ANOTHER BREAK IS EXPECTED ON MON BEFORE THE NEXT FRONT ARRIVES MON
NIGHT OR TUE. THIS FRONT DOES NOT CURRENTLY LOOK ALL THAT
IMPRESSIVE IN THE FCST MODELS...BUT ANOTHER ROUND OF LOW END SMALL
CRAFT ADVISORY WINDS IS CURRENTLY BEING ADVERTISED. FCST
CONFIDENCE DECREASES FOR THE LATTER HALF OF NEXT WEEK...BUT NO
MAJOR WEATHER SYSTEMS ARE CURRENTLY EXPECTED. PYLE

&&

.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 251027
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
326 AM PDT SAT APR 25 2015

.SYNOPSIS...UPPER LEVEL LOW PRESSURE CONTINUES TO BRING COOL AND
UNSETTLED WEATHER TO THE PACIFIC NORTHWEST. EXPECT VALLEY RAIN AND
MOUNTAIN SNOW SHOWERS TO CONTINUE TODAY. ANY HEAVIER SHOWERS MAY
PRODUCE SMALL HAIL AND LIGHTNING...ESPECIALLY EARLY THIS AFTERNOON.
THE UPPER LOW WILL WEAKEN AND MOVE EAST BY THIS EVENING...WITH HIGH
PRESSURE BRINGING A SWIFT END TO ANY LINGERING SHOWERS. A WARM FRONT
MAY CLIP THE REGION WITH SOME LIGHT RAIN SUNDAY AND SUNDAY NIGHT...
MOSTLY ALONG THE NORTH COAST. MONDAY WILL BE DRIER AND MUCH WARMER AS
A STRONG UPPER LEVEL RIDGE BUILDS IN FROM THE SOUTH. THE NEXT COLD
FRONT MAY BRING MORE SHOWERS AS EARLY AS TUESDAY...WITH MORE SHOWERS
POSSIBLE FOR THE REST OF THE WEEK AS ANOTHER UPPER LEVEL TROUGH
SETTLES NEAR THE PACIFIC NORTHWEST.

&&

.SHORT TERM...TODAY THROUGH MONDAY...NWS DOPPLER RADAR CONTINUES TO
SHOW SEVERAL SHOWERS MOVING ACROSS SW WASHINGTON AND NW OREGON THIS
MORNING...AS THE AIR MASS REMAINS COOL...MOIST AND UNSTABLE DUE TO AN
UPPER LEVEL LOW CENTERED OVER VANCOUVER ISLAND. ONE LAST LOBE OF COOL
AIR ALOFT IS EXPECTED TO PIVOT ACROSS THE FORECAST AREA AROUND MIDDAY
TODAY...COMBINING WITH OCCASIONAL SUNSHINE TO PRODUCE ANOTHER SPIKE
IN SHOWER ACTIVITY THIS MORNING INTO MID AFTERNOON.

WITH 500 MB TEMPS AROUND -30 DEG C WITHIN THE COOL CORE ALOFT...THE
POTENTIAL EXISTS FOR SOMEWHAT DEEPER CONVECTION THAN FRIDAY. A FEW
STRAY CLAPS OF THUNDER WERE REPORTED FRIDAY...EVEN WITH MILDER AIR
ALOFT. THEREFORE THE POTENTIAL EXISTS FOR ISOLATED THUNDERSTORMS
TODAY...ESPECIALLY NORTH OF SALEM. WITH FREEZING LEVELS HOVERING IN
THE 4000-5000 FT RANGE...HEAVIER SHOWERS SHOULD ALSO HAVE AN EASY
TIME PRODUCING SMALL HAIL. SHEAR PROFILES LOOK WEAK AND CAPE IS
MINIMAL...SO WE DO NOT EXPECT ANYTHING TO APPROACH SEVERE LIMITS.

THE CASCADES HAVE ALREADY RECEIVED A FEW INCHES OF SNOW...WITH AS
MUCH AS 6-8 INCHES BEING REPORTED AT TIMBERLINE SINCE THURSDAY. A
COUPLE MORE INCHES COULD ACCUMULATE FROM SNOW SHOWERS TODAY...BUT
ACCUMULATIONS WILL BE SPOTTY. SOME WET SNOW IS EXPECTED AT PASS
LEVEL...THOUGH THE STRONG APRIL SUN WILL PROBABLY MELT MOST SNOW OFF
THE ROADS BY MID-MORNING.

INSTABILITY WILL COME TO A QUICK END FROM TOP TO BOTTOM LATER THIS
AFTERNOON AND EVENING...AS TEMPS WARM ALOFT AND COOL AT THE SURFACE
WITH THE LOSS OF SOLAR HEATING. MEANWHILE HIGH PRESSURE WILL BUILD
ACROSS SW WA/NW OR...BRINGING SUBSIDENCE. THIS SHOULD BRING A SWIFT
END TO ANY LINGERING SHOWERS THIS EVENING. SOME VALLEY FOG IS
POSSIBLE IF SKIES STAY CLEAR TONIGHT...BUT HIGH CLOUDS AHEAD OF AN
APPROACHING WARM FRONT WILL PROBABLY MAKE IT DIFFICULT FOR FOG TO
BECOME TOO WIDESPREAD TONIGHT AND SUNDAY MORNING.

MODELS ARE FINALLY SHOWING SOME AGREEMENT THAT THE WARM FRONT WILL
BRUSH THE NORTH COAST WITH SOME RAIN WHILE MUCH OF THE WILLAMETTE
VALLEY AND OREGON CASCADES REMAIN DRY. MUCH WARMER AIR BEHIND THE
FRONT WILL CAUSE A SHARP INCREASE IN TEMPS MONDAY. WITH 850 MB TEMPS
FCST TO BE IN THE +12 TO +14 DEG C RANGE...TEMPS INLAND COULD PUSH 80
DEGREES IN THE VALLEYS.  WEAGLE

.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...MODELS CONTINUE TO
STRUGGLE WITH THE DETAILS TUESDAY AND BEYOND...THOUGH THEY ARE COMING
INTO BETTER AGREEMENT WITH THE GENERAL IDEA OF PUSHING THE MEAN RIDGE
POSITION EASTWARD INTO THE ROCKIES. THIS WOULD OPEN THE DOOR FOR MORE
UNSETTLED WEATHER BEGINNING WITH THE COLD FRONT TUESDAY AND
CONTINUING FOR THE REMAINDER OF THE WEEK AS A LONGWAVE UPPER TROUGH
PARKS OVER THE PAC NW. THERE REMAINS GREAT VARIATION BETWEEN
OPERATIONAL MODELS AND THEIR ENSEMBLE MEMBERS AS TO WHEN INDIVIDUAL
DISTURBANCES WOULD BRING CHANCES FOR RAIN. INCREASED POPS A BIT
CONSIDERING THE PERSISTENT LONGWAVE TROUGH...BUT HELD THEM NEAR CLIMO
DUE TO THE TIMING UNCERTAINTY. TEMPS SHOULD COOL BACK DOWN TO WITHIN
A FEW DEGREES OF NORMAL MIDWEEK...PERHAPS TRENDING BACK BELOW NORMAL
TOWARD THE END OF THE WEEK.  WEAGLE

&&

.AVIATION...A SHOWERY PATTERN TO CONTINUE THROUGH THIS AFTERNOON
AS A COLD UPPER LEVEL TROUGH GRADUALLY MOVES INLAND. EXPECT
PRIMARILY VFR CONDITIONS TO PERSIST...WITH PERIODIC BRIEF MVFR
CIGS DURING HEAVIER SHOWERS. THERE IS ALSO A CHANCE FOR ISOLATED
THUNDERSTORMS AND SMALL HAIL...BUT CONFIDENCE IN LOCATION AND
TIMING IS NOT HIGH ENOUGH TO INCLUDE IN TAFS. AS THE TROUGH PUSHES
FURTHER EAST AND HIGH PRES BUILDS IN BEHIND...SHOWERS WILL BEGIN
TO TAPER OFF ALONG THE COAST IN THE MID AFTERNOON AND OVER THE
INTERIOR DURING THE LATE AFTERNOON AND EARLY EVENING. HIGH PRES
STRENGTHENS OVERNIGHT SAT INTO SUN MORNING...POSSIBLY ALLOWING PATCHY
FOG MAY TO DEVELOP TOWARD 12Z SUN.

KPDX AND APPROACHES...SHOWERS CHANCES CONTINUE THROUGH THIS
AFTERNOON. EXPECT MAINLY VFR WITH BRIEF PERIODS OF MVFR DURING
HEAVIER SHOWERS. THERE IS A THREAT FOR THUNDERSTORMS AT THE
TERMINAL OR IN THE VICINITY BETWEEN 18Z SAT AND 00Z SUN. PYLE

&&

.MARINE...SEAS HAVE REMAINED A LITTLE HIGHER THAN THE ENP GUIDANCE
WAS SUGGESTING FOR THIS MORNING. THEY ARE CURRENTLY SITTING AT 8
TO 10 FT. EXPECT THEM TO GRADUALLY SUBSIDE THROUGH THE
DAY...EVENTUALLY REACHING 5 FT TONIGHT OR EARLY SUN MORNING.

FAIRLY BENIGN CONDITIONS ARE EXPECTED TODAY AND TONIGHT AS HIGH
PRES MOVES OVER THE WATERS AND THEN PUSHES INLAND. A WARM FRONT
IS THEN EXPECTED TO MOVE INTO THE WATERS SUN MORNING...THEN LIFT
NORTHWARD THROUGH THE DAY. THE LATEST MODEL RUNS HAVE TRENDED A
LITTLE STRONGER WITH THE WINDS...INDICATING THAT A PERIOD OF SMALL
CRAFT ADVISORY SOUTHERLY WINDS ARE LIKELY ON SUN ESPECIALLY OVER
THE OUTER WATERS. SEAS SHOULD ALSO INCREASE A BIT IN RESPONSE TO
THE WINDS...BUT ARE CURRENTLY EXPECTED TO REMAIN BELOW 10 FT.

ANOTHER BREAK IS EXPECTED ON MON BEFORE THE NEXT FRONT ARRIVES MON
NIGHT OR TUE. THIS FRONT DOES NOT CURRENTLY LOOK ALL THAT
IMPRESSIVE IN THE FCST MODELS...BUT ANOTHER ROUND OF LOW END SMALL
CRAFT ADVISORY WINDS IS CURRENTLY BEING ADVERTISED. FCST
CONFIDENCE DECREASES FOR THE LATTER HALF OF NEXT WEEK...BUT NO
MAJOR WEATHER SYSTEMS ARE CURRENTLY EXPECTED. PYLE

&&

.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 251027
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
326 AM PDT SAT APR 25 2015

.SYNOPSIS...UPPER LEVEL LOW PRESSURE CONTINUES TO BRING COOL AND
UNSETTLED WEATHER TO THE PACIFIC NORTHWEST. EXPECT VALLEY RAIN AND
MOUNTAIN SNOW SHOWERS TO CONTINUE TODAY. ANY HEAVIER SHOWERS MAY
PRODUCE SMALL HAIL AND LIGHTNING...ESPECIALLY EARLY THIS AFTERNOON.
THE UPPER LOW WILL WEAKEN AND MOVE EAST BY THIS EVENING...WITH HIGH
PRESSURE BRINGING A SWIFT END TO ANY LINGERING SHOWERS. A WARM FRONT
MAY CLIP THE REGION WITH SOME LIGHT RAIN SUNDAY AND SUNDAY NIGHT...
MOSTLY ALONG THE NORTH COAST. MONDAY WILL BE DRIER AND MUCH WARMER AS
A STRONG UPPER LEVEL RIDGE BUILDS IN FROM THE SOUTH. THE NEXT COLD
FRONT MAY BRING MORE SHOWERS AS EARLY AS TUESDAY...WITH MORE SHOWERS
POSSIBLE FOR THE REST OF THE WEEK AS ANOTHER UPPER LEVEL TROUGH
SETTLES NEAR THE PACIFIC NORTHWEST.

&&

.SHORT TERM...TODAY THROUGH MONDAY...NWS DOPPLER RADAR CONTINUES TO
SHOW SEVERAL SHOWERS MOVING ACROSS SW WASHINGTON AND NW OREGON THIS
MORNING...AS THE AIR MASS REMAINS COOL...MOIST AND UNSTABLE DUE TO AN
UPPER LEVEL LOW CENTERED OVER VANCOUVER ISLAND. ONE LAST LOBE OF COOL
AIR ALOFT IS EXPECTED TO PIVOT ACROSS THE FORECAST AREA AROUND MIDDAY
TODAY...COMBINING WITH OCCASIONAL SUNSHINE TO PRODUCE ANOTHER SPIKE
IN SHOWER ACTIVITY THIS MORNING INTO MID AFTERNOON.

WITH 500 MB TEMPS AROUND -30 DEG C WITHIN THE COOL CORE ALOFT...THE
POTENTIAL EXISTS FOR SOMEWHAT DEEPER CONVECTION THAN FRIDAY. A FEW
STRAY CLAPS OF THUNDER WERE REPORTED FRIDAY...EVEN WITH MILDER AIR
ALOFT. THEREFORE THE POTENTIAL EXISTS FOR ISOLATED THUNDERSTORMS
TODAY...ESPECIALLY NORTH OF SALEM. WITH FREEZING LEVELS HOVERING IN
THE 4000-5000 FT RANGE...HEAVIER SHOWERS SHOULD ALSO HAVE AN EASY
TIME PRODUCING SMALL HAIL. SHEAR PROFILES LOOK WEAK AND CAPE IS
MINIMAL...SO WE DO NOT EXPECT ANYTHING TO APPROACH SEVERE LIMITS.

THE CASCADES HAVE ALREADY RECEIVED A FEW INCHES OF SNOW...WITH AS
MUCH AS 6-8 INCHES BEING REPORTED AT TIMBERLINE SINCE THURSDAY. A
COUPLE MORE INCHES COULD ACCUMULATE FROM SNOW SHOWERS TODAY...BUT
ACCUMULATIONS WILL BE SPOTTY. SOME WET SNOW IS EXPECTED AT PASS
LEVEL...THOUGH THE STRONG APRIL SUN WILL PROBABLY MELT MOST SNOW OFF
THE ROADS BY MID-MORNING.

INSTABILITY WILL COME TO A QUICK END FROM TOP TO BOTTOM LATER THIS
AFTERNOON AND EVENING...AS TEMPS WARM ALOFT AND COOL AT THE SURFACE
WITH THE LOSS OF SOLAR HEATING. MEANWHILE HIGH PRESSURE WILL BUILD
ACROSS SW WA/NW OR...BRINGING SUBSIDENCE. THIS SHOULD BRING A SWIFT
END TO ANY LINGERING SHOWERS THIS EVENING. SOME VALLEY FOG IS
POSSIBLE IF SKIES STAY CLEAR TONIGHT...BUT HIGH CLOUDS AHEAD OF AN
APPROACHING WARM FRONT WILL PROBABLY MAKE IT DIFFICULT FOR FOG TO
BECOME TOO WIDESPREAD TONIGHT AND SUNDAY MORNING.

MODELS ARE FINALLY SHOWING SOME AGREEMENT THAT THE WARM FRONT WILL
BRUSH THE NORTH COAST WITH SOME RAIN WHILE MUCH OF THE WILLAMETTE
VALLEY AND OREGON CASCADES REMAIN DRY. MUCH WARMER AIR BEHIND THE
FRONT WILL CAUSE A SHARP INCREASE IN TEMPS MONDAY. WITH 850 MB TEMPS
FCST TO BE IN THE +12 TO +14 DEG C RANGE...TEMPS INLAND COULD PUSH 80
DEGREES IN THE VALLEYS.  WEAGLE

.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...MODELS CONTINUE TO
STRUGGLE WITH THE DETAILS TUESDAY AND BEYOND...THOUGH THEY ARE COMING
INTO BETTER AGREEMENT WITH THE GENERAL IDEA OF PUSHING THE MEAN RIDGE
POSITION EASTWARD INTO THE ROCKIES. THIS WOULD OPEN THE DOOR FOR MORE
UNSETTLED WEATHER BEGINNING WITH THE COLD FRONT TUESDAY AND
CONTINUING FOR THE REMAINDER OF THE WEEK AS A LONGWAVE UPPER TROUGH
PARKS OVER THE PAC NW. THERE REMAINS GREAT VARIATION BETWEEN
OPERATIONAL MODELS AND THEIR ENSEMBLE MEMBERS AS TO WHEN INDIVIDUAL
DISTURBANCES WOULD BRING CHANCES FOR RAIN. INCREASED POPS A BIT
CONSIDERING THE PERSISTENT LONGWAVE TROUGH...BUT HELD THEM NEAR CLIMO
DUE TO THE TIMING UNCERTAINTY. TEMPS SHOULD COOL BACK DOWN TO WITHIN
A FEW DEGREES OF NORMAL MIDWEEK...PERHAPS TRENDING BACK BELOW NORMAL
TOWARD THE END OF THE WEEK.  WEAGLE

&&

.AVIATION...A SHOWERY PATTERN TO CONTINUE THROUGH THIS AFTERNOON
AS A COLD UPPER LEVEL TROUGH GRADUALLY MOVES INLAND. EXPECT
PRIMARILY VFR CONDITIONS TO PERSIST...WITH PERIODIC BRIEF MVFR
CIGS DURING HEAVIER SHOWERS. THERE IS ALSO A CHANCE FOR ISOLATED
THUNDERSTORMS AND SMALL HAIL...BUT CONFIDENCE IN LOCATION AND
TIMING IS NOT HIGH ENOUGH TO INCLUDE IN TAFS. AS THE TROUGH PUSHES
FURTHER EAST AND HIGH PRES BUILDS IN BEHIND...SHOWERS WILL BEGIN
TO TAPER OFF ALONG THE COAST IN THE MID AFTERNOON AND OVER THE
INTERIOR DURING THE LATE AFTERNOON AND EARLY EVENING. HIGH PRES
STRENGTHENS OVERNIGHT SAT INTO SUN MORNING...POSSIBLY ALLOWING PATCHY
FOG MAY TO DEVELOP TOWARD 12Z SUN.

KPDX AND APPROACHES...SHOWERS CHANCES CONTINUE THROUGH THIS
AFTERNOON. EXPECT MAINLY VFR WITH BRIEF PERIODS OF MVFR DURING
HEAVIER SHOWERS. THERE IS A THREAT FOR THUNDERSTORMS AT THE
TERMINAL OR IN THE VICINITY BETWEEN 18Z SAT AND 00Z SUN. PYLE

&&

.MARINE...SEAS HAVE REMAINED A LITTLE HIGHER THAN THE ENP GUIDANCE
WAS SUGGESTING FOR THIS MORNING. THEY ARE CURRENTLY SITTING AT 8
TO 10 FT. EXPECT THEM TO GRADUALLY SUBSIDE THROUGH THE
DAY...EVENTUALLY REACHING 5 FT TONIGHT OR EARLY SUN MORNING.

FAIRLY BENIGN CONDITIONS ARE EXPECTED TODAY AND TONIGHT AS HIGH
PRES MOVES OVER THE WATERS AND THEN PUSHES INLAND. A WARM FRONT
IS THEN EXPECTED TO MOVE INTO THE WATERS SUN MORNING...THEN LIFT
NORTHWARD THROUGH THE DAY. THE LATEST MODEL RUNS HAVE TRENDED A
LITTLE STRONGER WITH THE WINDS...INDICATING THAT A PERIOD OF SMALL
CRAFT ADVISORY SOUTHERLY WINDS ARE LIKELY ON SUN ESPECIALLY OVER
THE OUTER WATERS. SEAS SHOULD ALSO INCREASE A BIT IN RESPONSE TO
THE WINDS...BUT ARE CURRENTLY EXPECTED TO REMAIN BELOW 10 FT.

ANOTHER BREAK IS EXPECTED ON MON BEFORE THE NEXT FRONT ARRIVES MON
NIGHT OR TUE. THIS FRONT DOES NOT CURRENTLY LOOK ALL THAT
IMPRESSIVE IN THE FCST MODELS...BUT ANOTHER ROUND OF LOW END SMALL
CRAFT ADVISORY WINDS IS CURRENTLY BEING ADVERTISED. FCST
CONFIDENCE DECREASES FOR THE LATTER HALF OF NEXT WEEK...BUT NO
MAJOR WEATHER SYSTEMS ARE CURRENTLY EXPECTED. PYLE

&&

.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 250351
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
851 PM PDT FRI APR 24 2015

.SYNOPSIS...A COOL SPRING UPPER LEVEL LOW CENTERED AROUND VANCOUVER
ISLAND WILL CONTINUE TO SPREAD SHOWERS INTO SOUTHWEST WASHINGTON AND
NORTHWEST OREGON TONIGHT INTO SATURDAY. SOME THUNDER IS POSSIBLE ON
SATURDAY. SNOW LEVELS WILL REMAIN NEAR OR BELOW THE CASCADE PASSES.
THE LOW WILL MOVE EAST THROUGH NORTHERN WASHINGTON ON SATURDAY...
WITH SHOWERS DECREASING LATE SATURDAY AND SATURDAY EVENING IN OUR
FORECAST AREA. A BRIEF UPPER RIDGE WILL BRING DRYING SATURDAY NIGHT
BUT WITH SOME POSSIBLE FOG OR LOW CLOUDS FORMING. A WARM FRONT WILL
BRUSH THE AREA SUNDAY AND SUNDAY NIGHT BEFORE LIFTING NORTH WITH
SUBSTANTIAL WARMING ON MONDAY. THE NEXT COLD FRONT MAY BRING MORE
SHOWERS BY THE MIDDLE OF NEXT WEEK.
&&

.SHORT TERM...WE HAD A FEW CLAPS OF THUNDER AROUND THE AREA LATE THIS
AFTERNOON...WITH ONE LIGHTNING STRIKE AS FAR SOUTH AS SOUTHERN LINN
COUNTY. AN UPPER LOW CONTINUES TO BE CENTERED AROUND VANCOUVER
ISLAND...SPREADING OCCASIONAL SHOWERS ONSHORE.

THE MODELS SHOW ANOTHER SHORT WAVE SWINGING AROUND THE BASE OF THE
LOW INTO OUR AREA LATER TONIGHT AND SATURDAY MORNING...FOLLOWED BY
ONE MORE SHORT WAVE ON THE BACK SIDE OF THE LOW AS THE WHOLE SYSTEM
MOVES OFF TO THE EAST LATER SATURDAY AND EARLY SATURDAY EVENING. THIS
SHOULD PROVIDE THE FORCING FOR MORE SHOWERS INTO SATURDAY...AND
POSSIBLY A FEW THUNDERSTORMS WITH SMALL HAIL AND GUSTY WINDS AGAIN.
THE BEST THREAT WILL BE LATE MORNING THROUGH MID AFTERNOON. THE
SHOWER ACTIVITY SHOULD EASE PRETTY QUICKLY LATE SATURDAY AFTERNOON
AND EARLY SATURDAY EVENING AS THE UPPER LEVEL SYSTEM MOVES OFF TO THE
EAST.

SNOW LEVELS WILL CONTINUE TO HOVER AROUND 3000 FEET IN THE CASCADES
EXCEPT CLOSER TO 4000 FEET OR SO IN LANE COUNTY. THE SNOW LEVELS WILL
BE LOWEST IN THE LATE NIGHT AND MORNING HOURS...RISING A BIT WITH THE
AFTERNOON SPRING SUN ANGLE. WE COULD STILL SEE AN INCH OR TWO OF SNOW
NEAR PASS ELEVATIONS LATER TONIGHT AND SATURDAY MORNING.

LOOK FOR DRY WEATHER BUT SOME AREAS OF FOG OR LOW CLOUDS SATURDAY
NIGHT INTO SUNDAY MORNING AS A BRIEF UPPER RIDGE MOVES IN. A WARM
FRONT IS FORECAST TO RIDE OVER THE RIDGE AND BRUSH AT LEAST A
PORTION OF OUR FORECAST AREA WITH SOME LIGHT RAIN SUNDAY AND SUNDAY
NIGHT. THE WARM FRONT IS FORECAST TO LIFT NORTH WITH CLEARING AND
SUBSTANTIAL WARMING ON MONDAY...WITH TEMPS HAVING A CHANCE TO REACH
CLOSE TO 80 DEGREES. TOLLESON

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH FRIDAY...MODELS ARE STILL SOMEWHAT INCONSISTENT
WITH THE TIMING OF SYSTEMS FORECAST TO MOVE THROUGH NEXT WEEK.RIDGE
OVER THE PACIFIC NORTHWEST GETS PUSHED OFF TO THE EAST MONDAY NIGHT
INTO TUESDAY AS AN UPPER-LEVEL TROUGH MOVES ONSHORE AND STALLS OVER
THE AREA. A COLD FRONT ASSOCIATED WITH THIS UPPER-LEVEL TROUGH MOVES
THROUGH DURING THE DAY ON TUESDAY...WITH THE ECMWF BRINGING THE FRONT
THROUGH DURING THE MORNING ON TUESDAY AND THE GFS BRINGING THE FRONT
THROUGH LATER IN THE AFTERNOON/EVENING ON TUESDAY. THE ECMWF SEEMS TO
BRING THE FRONT IN A LITTLE TOO FAST...WHILE THE GFS MIGHT BE TOO
SLOW...SO EXPECT THE FRONT TO MOVE THROUGH SOMETIME MIDDAY ON
TUESDAY. COOLED TEMPS A BIT ON TUESDAY AS EITHER AN INCREASE IN
CLOUDS AHEAD OF THE FRONT...OR CLOUDS AND RAIN WITH THE FRONTAL
SYSTEM WILL KEEP TEMPERATURES FROM REACHING AS WARM AS PREVIOUSLY
FORECAST. UNSTABLE AIRMASS UNDER UPPER LEVEL TROUGHING BEHIND THE
FRONT TUESDAY NIGHT INTO WEDNESDAY WILL LIKELY KEEP SCATTERED SHOWERS
ACROSS THE AREA UNTIL WEDNESDAY EVENING...WHEN SHOWERS SHOULD BEGIN
TO TAPER OFF EXCEPT MAYBE IN THE CASCADES AND NORTHERN COAST/COAST
RANGE.

A SHORTWAVE ON THE BACK SIDE OF THE STALLED UPPER-LEVEL TROUGH OVER
OUR AREA WILL MOVE THROUGH LATER NEXT WEEK...WITH INCONSISTENCY
BETWEEN THE GFS AND ECMWF ON THE TIMING OF THIS SYSTEM AS WELL.
RIGHT NOW...MODELS SUGGEST THAT THIS FRONT WILL MOVE THROUGH SOMETIME
ON THURSDAY...BRINGING MORE RAIN FOR THURSDAY INTO FRIDAY. -MCCOY
&&

.AVIATION...GENERALLY VFR THIS EVENING IN THE LOWER ELEVATIONS...
EXCEPT FOR LOCALIZED MVFR IN HEAVIER SHOWERS. WEB CAMS SUGGEST MVFR
OR WORSE IN THE CASCADES AND HIGHER ELEVATIONS OF THE OREGON COAST
RANGE AS WLY UPSLOPE FLOW CONTINUES TO FOCUS SHOWERS IN THOSE AREAS.
COLD UPPER LEVEL TROUGH WILL REMAIN OVER THE AREA THROUGH SAT. EXPECT
SHOWER ACTIVITY TO INCREASE SAT MORNING THROUGH EARLY
AFTERNOON...RESULTING IN A MIX OF MVFR AND VFR IN THE LOWLANDS AND
PRIMARILY MVFR OR WORSE OVER THE HIGHER TERRAIN. SHOWER ACTIVITY
SHOULD START TO DECREASE ALONG THE COAST IN THE MID TO LATE
AFTERNOON...AND REMAIN MORE FOCUSED FROM THE COAST RANGE AND WILLAPA
HILLS TO THE CASCADES. WILL ALSO HAVE A THREAT OF THUNDERSTORMS ALONG
THE S WA AND N OREGON COAST LATE TONIGHT THROUGH ABOUT 15Z SAT. THE
THREAT SHIFTS INLAND AFTER 15Z.

KPDX AND APPROACHES...EXPECT PRIMARILY VFR CONDITIONS THROUGH SAT
EVENING. HOWEVER...THERE WILL BE SHORT-LIVED PERIODS OF MVFR 12Z SAT
THROUGH 03Z SUN IN HEAVIER SHOWERS. THE FAVORED TIME FRAME LOOKS TO
BE 18Z SAT THROUGH 03Z SUN. THERE IS A THREAT FOR THUNDERSTORMS AT
THE TERMINAL OR IN THE VICINITY AFTER 15Z SAT. WEISHAAR
&&

.MARINE...NOT MUCH TO CHANGE IN THE MARINE FORECAST. WEST WIND
CONTINUES TO SLOWLY EASE...GENERALLY 10 TO 15 KT THIS EVENING. WIND
WILL TURN NW TO N LATE TONIGHT AND SAT...BUT SPEEDS TO REMAIN UNDER
15 KT. WARM FRONT MOVES ACROSS THE WATERS SUN...WHICH COULD PRODUCE
SMALL CRAFT ADVISORY LEVEL WIND IN THE NRN WATERS SUN. MODEL
DIFFERENCES GROW BEYOND MON WITH DIMINISHING FORECAST CONFIDENCE.

AS OF 03Z SEAS HOVERING AT OR SLIGHTLY ABOVE 10 FT. LATEST WAVE
GUIDANCE SUGGESTS SEAS DROP BELOW 10 FT BEFORE 06Z TONIGHT.
HOWEVER...WILL LET THE SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS RUN
ITS COURSE THROUGH 06Z. FAIRLY BENIGN SEA CONDITIONS SAT AFTERNOON
THROUGH SUN...WITH HEIGHTS LOWERING TO 5 FT OR SO BY LATE SAT
AFTERNOON. SEAS REMAIN BELOW 10 FEET THROUGH EARLY NEXT WEEK.
WEISHAAR
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT
     THIS EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
     11 PM PDT THIS EVENING.

&&

$$

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 250351
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
851 PM PDT FRI APR 24 2015

.SYNOPSIS...A COOL SPRING UPPER LEVEL LOW CENTERED AROUND VANCOUVER
ISLAND WILL CONTINUE TO SPREAD SHOWERS INTO SOUTHWEST WASHINGTON AND
NORTHWEST OREGON TONIGHT INTO SATURDAY. SOME THUNDER IS POSSIBLE ON
SATURDAY. SNOW LEVELS WILL REMAIN NEAR OR BELOW THE CASCADE PASSES.
THE LOW WILL MOVE EAST THROUGH NORTHERN WASHINGTON ON SATURDAY...
WITH SHOWERS DECREASING LATE SATURDAY AND SATURDAY EVENING IN OUR
FORECAST AREA. A BRIEF UPPER RIDGE WILL BRING DRYING SATURDAY NIGHT
BUT WITH SOME POSSIBLE FOG OR LOW CLOUDS FORMING. A WARM FRONT WILL
BRUSH THE AREA SUNDAY AND SUNDAY NIGHT BEFORE LIFTING NORTH WITH
SUBSTANTIAL WARMING ON MONDAY. THE NEXT COLD FRONT MAY BRING MORE
SHOWERS BY THE MIDDLE OF NEXT WEEK.
&&

.SHORT TERM...WE HAD A FEW CLAPS OF THUNDER AROUND THE AREA LATE THIS
AFTERNOON...WITH ONE LIGHTNING STRIKE AS FAR SOUTH AS SOUTHERN LINN
COUNTY. AN UPPER LOW CONTINUES TO BE CENTERED AROUND VANCOUVER
ISLAND...SPREADING OCCASIONAL SHOWERS ONSHORE.

THE MODELS SHOW ANOTHER SHORT WAVE SWINGING AROUND THE BASE OF THE
LOW INTO OUR AREA LATER TONIGHT AND SATURDAY MORNING...FOLLOWED BY
ONE MORE SHORT WAVE ON THE BACK SIDE OF THE LOW AS THE WHOLE SYSTEM
MOVES OFF TO THE EAST LATER SATURDAY AND EARLY SATURDAY EVENING. THIS
SHOULD PROVIDE THE FORCING FOR MORE SHOWERS INTO SATURDAY...AND
POSSIBLY A FEW THUNDERSTORMS WITH SMALL HAIL AND GUSTY WINDS AGAIN.
THE BEST THREAT WILL BE LATE MORNING THROUGH MID AFTERNOON. THE
SHOWER ACTIVITY SHOULD EASE PRETTY QUICKLY LATE SATURDAY AFTERNOON
AND EARLY SATURDAY EVENING AS THE UPPER LEVEL SYSTEM MOVES OFF TO THE
EAST.

SNOW LEVELS WILL CONTINUE TO HOVER AROUND 3000 FEET IN THE CASCADES
EXCEPT CLOSER TO 4000 FEET OR SO IN LANE COUNTY. THE SNOW LEVELS WILL
BE LOWEST IN THE LATE NIGHT AND MORNING HOURS...RISING A BIT WITH THE
AFTERNOON SPRING SUN ANGLE. WE COULD STILL SEE AN INCH OR TWO OF SNOW
NEAR PASS ELEVATIONS LATER TONIGHT AND SATURDAY MORNING.

LOOK FOR DRY WEATHER BUT SOME AREAS OF FOG OR LOW CLOUDS SATURDAY
NIGHT INTO SUNDAY MORNING AS A BRIEF UPPER RIDGE MOVES IN. A WARM
FRONT IS FORECAST TO RIDE OVER THE RIDGE AND BRUSH AT LEAST A
PORTION OF OUR FORECAST AREA WITH SOME LIGHT RAIN SUNDAY AND SUNDAY
NIGHT. THE WARM FRONT IS FORECAST TO LIFT NORTH WITH CLEARING AND
SUBSTANTIAL WARMING ON MONDAY...WITH TEMPS HAVING A CHANCE TO REACH
CLOSE TO 80 DEGREES. TOLLESON

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH FRIDAY...MODELS ARE STILL SOMEWHAT INCONSISTENT
WITH THE TIMING OF SYSTEMS FORECAST TO MOVE THROUGH NEXT WEEK.RIDGE
OVER THE PACIFIC NORTHWEST GETS PUSHED OFF TO THE EAST MONDAY NIGHT
INTO TUESDAY AS AN UPPER-LEVEL TROUGH MOVES ONSHORE AND STALLS OVER
THE AREA. A COLD FRONT ASSOCIATED WITH THIS UPPER-LEVEL TROUGH MOVES
THROUGH DURING THE DAY ON TUESDAY...WITH THE ECMWF BRINGING THE FRONT
THROUGH DURING THE MORNING ON TUESDAY AND THE GFS BRINGING THE FRONT
THROUGH LATER IN THE AFTERNOON/EVENING ON TUESDAY. THE ECMWF SEEMS TO
BRING THE FRONT IN A LITTLE TOO FAST...WHILE THE GFS MIGHT BE TOO
SLOW...SO EXPECT THE FRONT TO MOVE THROUGH SOMETIME MIDDAY ON
TUESDAY. COOLED TEMPS A BIT ON TUESDAY AS EITHER AN INCREASE IN
CLOUDS AHEAD OF THE FRONT...OR CLOUDS AND RAIN WITH THE FRONTAL
SYSTEM WILL KEEP TEMPERATURES FROM REACHING AS WARM AS PREVIOUSLY
FORECAST. UNSTABLE AIRMASS UNDER UPPER LEVEL TROUGHING BEHIND THE
FRONT TUESDAY NIGHT INTO WEDNESDAY WILL LIKELY KEEP SCATTERED SHOWERS
ACROSS THE AREA UNTIL WEDNESDAY EVENING...WHEN SHOWERS SHOULD BEGIN
TO TAPER OFF EXCEPT MAYBE IN THE CASCADES AND NORTHERN COAST/COAST
RANGE.

A SHORTWAVE ON THE BACK SIDE OF THE STALLED UPPER-LEVEL TROUGH OVER
OUR AREA WILL MOVE THROUGH LATER NEXT WEEK...WITH INCONSISTENCY
BETWEEN THE GFS AND ECMWF ON THE TIMING OF THIS SYSTEM AS WELL.
RIGHT NOW...MODELS SUGGEST THAT THIS FRONT WILL MOVE THROUGH SOMETIME
ON THURSDAY...BRINGING MORE RAIN FOR THURSDAY INTO FRIDAY. -MCCOY
&&

.AVIATION...GENERALLY VFR THIS EVENING IN THE LOWER ELEVATIONS...
EXCEPT FOR LOCALIZED MVFR IN HEAVIER SHOWERS. WEB CAMS SUGGEST MVFR
OR WORSE IN THE CASCADES AND HIGHER ELEVATIONS OF THE OREGON COAST
RANGE AS WLY UPSLOPE FLOW CONTINUES TO FOCUS SHOWERS IN THOSE AREAS.
COLD UPPER LEVEL TROUGH WILL REMAIN OVER THE AREA THROUGH SAT. EXPECT
SHOWER ACTIVITY TO INCREASE SAT MORNING THROUGH EARLY
AFTERNOON...RESULTING IN A MIX OF MVFR AND VFR IN THE LOWLANDS AND
PRIMARILY MVFR OR WORSE OVER THE HIGHER TERRAIN. SHOWER ACTIVITY
SHOULD START TO DECREASE ALONG THE COAST IN THE MID TO LATE
AFTERNOON...AND REMAIN MORE FOCUSED FROM THE COAST RANGE AND WILLAPA
HILLS TO THE CASCADES. WILL ALSO HAVE A THREAT OF THUNDERSTORMS ALONG
THE S WA AND N OREGON COAST LATE TONIGHT THROUGH ABOUT 15Z SAT. THE
THREAT SHIFTS INLAND AFTER 15Z.

KPDX AND APPROACHES...EXPECT PRIMARILY VFR CONDITIONS THROUGH SAT
EVENING. HOWEVER...THERE WILL BE SHORT-LIVED PERIODS OF MVFR 12Z SAT
THROUGH 03Z SUN IN HEAVIER SHOWERS. THE FAVORED TIME FRAME LOOKS TO
BE 18Z SAT THROUGH 03Z SUN. THERE IS A THREAT FOR THUNDERSTORMS AT
THE TERMINAL OR IN THE VICINITY AFTER 15Z SAT. WEISHAAR
&&

.MARINE...NOT MUCH TO CHANGE IN THE MARINE FORECAST. WEST WIND
CONTINUES TO SLOWLY EASE...GENERALLY 10 TO 15 KT THIS EVENING. WIND
WILL TURN NW TO N LATE TONIGHT AND SAT...BUT SPEEDS TO REMAIN UNDER
15 KT. WARM FRONT MOVES ACROSS THE WATERS SUN...WHICH COULD PRODUCE
SMALL CRAFT ADVISORY LEVEL WIND IN THE NRN WATERS SUN. MODEL
DIFFERENCES GROW BEYOND MON WITH DIMINISHING FORECAST CONFIDENCE.

AS OF 03Z SEAS HOVERING AT OR SLIGHTLY ABOVE 10 FT. LATEST WAVE
GUIDANCE SUGGESTS SEAS DROP BELOW 10 FT BEFORE 06Z TONIGHT.
HOWEVER...WILL LET THE SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS RUN
ITS COURSE THROUGH 06Z. FAIRLY BENIGN SEA CONDITIONS SAT AFTERNOON
THROUGH SUN...WITH HEIGHTS LOWERING TO 5 FT OR SO BY LATE SAT
AFTERNOON. SEAS REMAIN BELOW 10 FEET THROUGH EARLY NEXT WEEK.
WEISHAAR
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT
     THIS EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
     11 PM PDT THIS EVENING.

&&

$$

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 250351
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
851 PM PDT FRI APR 24 2015

.SYNOPSIS...A COOL SPRING UPPER LEVEL LOW CENTERED AROUND VANCOUVER
ISLAND WILL CONTINUE TO SPREAD SHOWERS INTO SOUTHWEST WASHINGTON AND
NORTHWEST OREGON TONIGHT INTO SATURDAY. SOME THUNDER IS POSSIBLE ON
SATURDAY. SNOW LEVELS WILL REMAIN NEAR OR BELOW THE CASCADE PASSES.
THE LOW WILL MOVE EAST THROUGH NORTHERN WASHINGTON ON SATURDAY...
WITH SHOWERS DECREASING LATE SATURDAY AND SATURDAY EVENING IN OUR
FORECAST AREA. A BRIEF UPPER RIDGE WILL BRING DRYING SATURDAY NIGHT
BUT WITH SOME POSSIBLE FOG OR LOW CLOUDS FORMING. A WARM FRONT WILL
BRUSH THE AREA SUNDAY AND SUNDAY NIGHT BEFORE LIFTING NORTH WITH
SUBSTANTIAL WARMING ON MONDAY. THE NEXT COLD FRONT MAY BRING MORE
SHOWERS BY THE MIDDLE OF NEXT WEEK.
&&

.SHORT TERM...WE HAD A FEW CLAPS OF THUNDER AROUND THE AREA LATE THIS
AFTERNOON...WITH ONE LIGHTNING STRIKE AS FAR SOUTH AS SOUTHERN LINN
COUNTY. AN UPPER LOW CONTINUES TO BE CENTERED AROUND VANCOUVER
ISLAND...SPREADING OCCASIONAL SHOWERS ONSHORE.

THE MODELS SHOW ANOTHER SHORT WAVE SWINGING AROUND THE BASE OF THE
LOW INTO OUR AREA LATER TONIGHT AND SATURDAY MORNING...FOLLOWED BY
ONE MORE SHORT WAVE ON THE BACK SIDE OF THE LOW AS THE WHOLE SYSTEM
MOVES OFF TO THE EAST LATER SATURDAY AND EARLY SATURDAY EVENING. THIS
SHOULD PROVIDE THE FORCING FOR MORE SHOWERS INTO SATURDAY...AND
POSSIBLY A FEW THUNDERSTORMS WITH SMALL HAIL AND GUSTY WINDS AGAIN.
THE BEST THREAT WILL BE LATE MORNING THROUGH MID AFTERNOON. THE
SHOWER ACTIVITY SHOULD EASE PRETTY QUICKLY LATE SATURDAY AFTERNOON
AND EARLY SATURDAY EVENING AS THE UPPER LEVEL SYSTEM MOVES OFF TO THE
EAST.

SNOW LEVELS WILL CONTINUE TO HOVER AROUND 3000 FEET IN THE CASCADES
EXCEPT CLOSER TO 4000 FEET OR SO IN LANE COUNTY. THE SNOW LEVELS WILL
BE LOWEST IN THE LATE NIGHT AND MORNING HOURS...RISING A BIT WITH THE
AFTERNOON SPRING SUN ANGLE. WE COULD STILL SEE AN INCH OR TWO OF SNOW
NEAR PASS ELEVATIONS LATER TONIGHT AND SATURDAY MORNING.

LOOK FOR DRY WEATHER BUT SOME AREAS OF FOG OR LOW CLOUDS SATURDAY
NIGHT INTO SUNDAY MORNING AS A BRIEF UPPER RIDGE MOVES IN. A WARM
FRONT IS FORECAST TO RIDE OVER THE RIDGE AND BRUSH AT LEAST A
PORTION OF OUR FORECAST AREA WITH SOME LIGHT RAIN SUNDAY AND SUNDAY
NIGHT. THE WARM FRONT IS FORECAST TO LIFT NORTH WITH CLEARING AND
SUBSTANTIAL WARMING ON MONDAY...WITH TEMPS HAVING A CHANCE TO REACH
CLOSE TO 80 DEGREES. TOLLESON

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH FRIDAY...MODELS ARE STILL SOMEWHAT INCONSISTENT
WITH THE TIMING OF SYSTEMS FORECAST TO MOVE THROUGH NEXT WEEK.RIDGE
OVER THE PACIFIC NORTHWEST GETS PUSHED OFF TO THE EAST MONDAY NIGHT
INTO TUESDAY AS AN UPPER-LEVEL TROUGH MOVES ONSHORE AND STALLS OVER
THE AREA. A COLD FRONT ASSOCIATED WITH THIS UPPER-LEVEL TROUGH MOVES
THROUGH DURING THE DAY ON TUESDAY...WITH THE ECMWF BRINGING THE FRONT
THROUGH DURING THE MORNING ON TUESDAY AND THE GFS BRINGING THE FRONT
THROUGH LATER IN THE AFTERNOON/EVENING ON TUESDAY. THE ECMWF SEEMS TO
BRING THE FRONT IN A LITTLE TOO FAST...WHILE THE GFS MIGHT BE TOO
SLOW...SO EXPECT THE FRONT TO MOVE THROUGH SOMETIME MIDDAY ON
TUESDAY. COOLED TEMPS A BIT ON TUESDAY AS EITHER AN INCREASE IN
CLOUDS AHEAD OF THE FRONT...OR CLOUDS AND RAIN WITH THE FRONTAL
SYSTEM WILL KEEP TEMPERATURES FROM REACHING AS WARM AS PREVIOUSLY
FORECAST. UNSTABLE AIRMASS UNDER UPPER LEVEL TROUGHING BEHIND THE
FRONT TUESDAY NIGHT INTO WEDNESDAY WILL LIKELY KEEP SCATTERED SHOWERS
ACROSS THE AREA UNTIL WEDNESDAY EVENING...WHEN SHOWERS SHOULD BEGIN
TO TAPER OFF EXCEPT MAYBE IN THE CASCADES AND NORTHERN COAST/COAST
RANGE.

A SHORTWAVE ON THE BACK SIDE OF THE STALLED UPPER-LEVEL TROUGH OVER
OUR AREA WILL MOVE THROUGH LATER NEXT WEEK...WITH INCONSISTENCY
BETWEEN THE GFS AND ECMWF ON THE TIMING OF THIS SYSTEM AS WELL.
RIGHT NOW...MODELS SUGGEST THAT THIS FRONT WILL MOVE THROUGH SOMETIME
ON THURSDAY...BRINGING MORE RAIN FOR THURSDAY INTO FRIDAY. -MCCOY
&&

.AVIATION...GENERALLY VFR THIS EVENING IN THE LOWER ELEVATIONS...
EXCEPT FOR LOCALIZED MVFR IN HEAVIER SHOWERS. WEB CAMS SUGGEST MVFR
OR WORSE IN THE CASCADES AND HIGHER ELEVATIONS OF THE OREGON COAST
RANGE AS WLY UPSLOPE FLOW CONTINUES TO FOCUS SHOWERS IN THOSE AREAS.
COLD UPPER LEVEL TROUGH WILL REMAIN OVER THE AREA THROUGH SAT. EXPECT
SHOWER ACTIVITY TO INCREASE SAT MORNING THROUGH EARLY
AFTERNOON...RESULTING IN A MIX OF MVFR AND VFR IN THE LOWLANDS AND
PRIMARILY MVFR OR WORSE OVER THE HIGHER TERRAIN. SHOWER ACTIVITY
SHOULD START TO DECREASE ALONG THE COAST IN THE MID TO LATE
AFTERNOON...AND REMAIN MORE FOCUSED FROM THE COAST RANGE AND WILLAPA
HILLS TO THE CASCADES. WILL ALSO HAVE A THREAT OF THUNDERSTORMS ALONG
THE S WA AND N OREGON COAST LATE TONIGHT THROUGH ABOUT 15Z SAT. THE
THREAT SHIFTS INLAND AFTER 15Z.

KPDX AND APPROACHES...EXPECT PRIMARILY VFR CONDITIONS THROUGH SAT
EVENING. HOWEVER...THERE WILL BE SHORT-LIVED PERIODS OF MVFR 12Z SAT
THROUGH 03Z SUN IN HEAVIER SHOWERS. THE FAVORED TIME FRAME LOOKS TO
BE 18Z SAT THROUGH 03Z SUN. THERE IS A THREAT FOR THUNDERSTORMS AT
THE TERMINAL OR IN THE VICINITY AFTER 15Z SAT. WEISHAAR
&&

.MARINE...NOT MUCH TO CHANGE IN THE MARINE FORECAST. WEST WIND
CONTINUES TO SLOWLY EASE...GENERALLY 10 TO 15 KT THIS EVENING. WIND
WILL TURN NW TO N LATE TONIGHT AND SAT...BUT SPEEDS TO REMAIN UNDER
15 KT. WARM FRONT MOVES ACROSS THE WATERS SUN...WHICH COULD PRODUCE
SMALL CRAFT ADVISORY LEVEL WIND IN THE NRN WATERS SUN. MODEL
DIFFERENCES GROW BEYOND MON WITH DIMINISHING FORECAST CONFIDENCE.

AS OF 03Z SEAS HOVERING AT OR SLIGHTLY ABOVE 10 FT. LATEST WAVE
GUIDANCE SUGGESTS SEAS DROP BELOW 10 FT BEFORE 06Z TONIGHT.
HOWEVER...WILL LET THE SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS RUN
ITS COURSE THROUGH 06Z. FAIRLY BENIGN SEA CONDITIONS SAT AFTERNOON
THROUGH SUN...WITH HEIGHTS LOWERING TO 5 FT OR SO BY LATE SAT
AFTERNOON. SEAS REMAIN BELOW 10 FEET THROUGH EARLY NEXT WEEK.
WEISHAAR
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT
     THIS EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
     11 PM PDT THIS EVENING.

&&

$$

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 250351
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
851 PM PDT FRI APR 24 2015

.SYNOPSIS...A COOL SPRING UPPER LEVEL LOW CENTERED AROUND VANCOUVER
ISLAND WILL CONTINUE TO SPREAD SHOWERS INTO SOUTHWEST WASHINGTON AND
NORTHWEST OREGON TONIGHT INTO SATURDAY. SOME THUNDER IS POSSIBLE ON
SATURDAY. SNOW LEVELS WILL REMAIN NEAR OR BELOW THE CASCADE PASSES.
THE LOW WILL MOVE EAST THROUGH NORTHERN WASHINGTON ON SATURDAY...
WITH SHOWERS DECREASING LATE SATURDAY AND SATURDAY EVENING IN OUR
FORECAST AREA. A BRIEF UPPER RIDGE WILL BRING DRYING SATURDAY NIGHT
BUT WITH SOME POSSIBLE FOG OR LOW CLOUDS FORMING. A WARM FRONT WILL
BRUSH THE AREA SUNDAY AND SUNDAY NIGHT BEFORE LIFTING NORTH WITH
SUBSTANTIAL WARMING ON MONDAY. THE NEXT COLD FRONT MAY BRING MORE
SHOWERS BY THE MIDDLE OF NEXT WEEK.
&&

.SHORT TERM...WE HAD A FEW CLAPS OF THUNDER AROUND THE AREA LATE THIS
AFTERNOON...WITH ONE LIGHTNING STRIKE AS FAR SOUTH AS SOUTHERN LINN
COUNTY. AN UPPER LOW CONTINUES TO BE CENTERED AROUND VANCOUVER
ISLAND...SPREADING OCCASIONAL SHOWERS ONSHORE.

THE MODELS SHOW ANOTHER SHORT WAVE SWINGING AROUND THE BASE OF THE
LOW INTO OUR AREA LATER TONIGHT AND SATURDAY MORNING...FOLLOWED BY
ONE MORE SHORT WAVE ON THE BACK SIDE OF THE LOW AS THE WHOLE SYSTEM
MOVES OFF TO THE EAST LATER SATURDAY AND EARLY SATURDAY EVENING. THIS
SHOULD PROVIDE THE FORCING FOR MORE SHOWERS INTO SATURDAY...AND
POSSIBLY A FEW THUNDERSTORMS WITH SMALL HAIL AND GUSTY WINDS AGAIN.
THE BEST THREAT WILL BE LATE MORNING THROUGH MID AFTERNOON. THE
SHOWER ACTIVITY SHOULD EASE PRETTY QUICKLY LATE SATURDAY AFTERNOON
AND EARLY SATURDAY EVENING AS THE UPPER LEVEL SYSTEM MOVES OFF TO THE
EAST.

SNOW LEVELS WILL CONTINUE TO HOVER AROUND 3000 FEET IN THE CASCADES
EXCEPT CLOSER TO 4000 FEET OR SO IN LANE COUNTY. THE SNOW LEVELS WILL
BE LOWEST IN THE LATE NIGHT AND MORNING HOURS...RISING A BIT WITH THE
AFTERNOON SPRING SUN ANGLE. WE COULD STILL SEE AN INCH OR TWO OF SNOW
NEAR PASS ELEVATIONS LATER TONIGHT AND SATURDAY MORNING.

LOOK FOR DRY WEATHER BUT SOME AREAS OF FOG OR LOW CLOUDS SATURDAY
NIGHT INTO SUNDAY MORNING AS A BRIEF UPPER RIDGE MOVES IN. A WARM
FRONT IS FORECAST TO RIDE OVER THE RIDGE AND BRUSH AT LEAST A
PORTION OF OUR FORECAST AREA WITH SOME LIGHT RAIN SUNDAY AND SUNDAY
NIGHT. THE WARM FRONT IS FORECAST TO LIFT NORTH WITH CLEARING AND
SUBSTANTIAL WARMING ON MONDAY...WITH TEMPS HAVING A CHANCE TO REACH
CLOSE TO 80 DEGREES. TOLLESON

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH FRIDAY...MODELS ARE STILL SOMEWHAT INCONSISTENT
WITH THE TIMING OF SYSTEMS FORECAST TO MOVE THROUGH NEXT WEEK.RIDGE
OVER THE PACIFIC NORTHWEST GETS PUSHED OFF TO THE EAST MONDAY NIGHT
INTO TUESDAY AS AN UPPER-LEVEL TROUGH MOVES ONSHORE AND STALLS OVER
THE AREA. A COLD FRONT ASSOCIATED WITH THIS UPPER-LEVEL TROUGH MOVES
THROUGH DURING THE DAY ON TUESDAY...WITH THE ECMWF BRINGING THE FRONT
THROUGH DURING THE MORNING ON TUESDAY AND THE GFS BRINGING THE FRONT
THROUGH LATER IN THE AFTERNOON/EVENING ON TUESDAY. THE ECMWF SEEMS TO
BRING THE FRONT IN A LITTLE TOO FAST...WHILE THE GFS MIGHT BE TOO
SLOW...SO EXPECT THE FRONT TO MOVE THROUGH SOMETIME MIDDAY ON
TUESDAY. COOLED TEMPS A BIT ON TUESDAY AS EITHER AN INCREASE IN
CLOUDS AHEAD OF THE FRONT...OR CLOUDS AND RAIN WITH THE FRONTAL
SYSTEM WILL KEEP TEMPERATURES FROM REACHING AS WARM AS PREVIOUSLY
FORECAST. UNSTABLE AIRMASS UNDER UPPER LEVEL TROUGHING BEHIND THE
FRONT TUESDAY NIGHT INTO WEDNESDAY WILL LIKELY KEEP SCATTERED SHOWERS
ACROSS THE AREA UNTIL WEDNESDAY EVENING...WHEN SHOWERS SHOULD BEGIN
TO TAPER OFF EXCEPT MAYBE IN THE CASCADES AND NORTHERN COAST/COAST
RANGE.

A SHORTWAVE ON THE BACK SIDE OF THE STALLED UPPER-LEVEL TROUGH OVER
OUR AREA WILL MOVE THROUGH LATER NEXT WEEK...WITH INCONSISTENCY
BETWEEN THE GFS AND ECMWF ON THE TIMING OF THIS SYSTEM AS WELL.
RIGHT NOW...MODELS SUGGEST THAT THIS FRONT WILL MOVE THROUGH SOMETIME
ON THURSDAY...BRINGING MORE RAIN FOR THURSDAY INTO FRIDAY. -MCCOY
&&

.AVIATION...GENERALLY VFR THIS EVENING IN THE LOWER ELEVATIONS...
EXCEPT FOR LOCALIZED MVFR IN HEAVIER SHOWERS. WEB CAMS SUGGEST MVFR
OR WORSE IN THE CASCADES AND HIGHER ELEVATIONS OF THE OREGON COAST
RANGE AS WLY UPSLOPE FLOW CONTINUES TO FOCUS SHOWERS IN THOSE AREAS.
COLD UPPER LEVEL TROUGH WILL REMAIN OVER THE AREA THROUGH SAT. EXPECT
SHOWER ACTIVITY TO INCREASE SAT MORNING THROUGH EARLY
AFTERNOON...RESULTING IN A MIX OF MVFR AND VFR IN THE LOWLANDS AND
PRIMARILY MVFR OR WORSE OVER THE HIGHER TERRAIN. SHOWER ACTIVITY
SHOULD START TO DECREASE ALONG THE COAST IN THE MID TO LATE
AFTERNOON...AND REMAIN MORE FOCUSED FROM THE COAST RANGE AND WILLAPA
HILLS TO THE CASCADES. WILL ALSO HAVE A THREAT OF THUNDERSTORMS ALONG
THE S WA AND N OREGON COAST LATE TONIGHT THROUGH ABOUT 15Z SAT. THE
THREAT SHIFTS INLAND AFTER 15Z.

KPDX AND APPROACHES...EXPECT PRIMARILY VFR CONDITIONS THROUGH SAT
EVENING. HOWEVER...THERE WILL BE SHORT-LIVED PERIODS OF MVFR 12Z SAT
THROUGH 03Z SUN IN HEAVIER SHOWERS. THE FAVORED TIME FRAME LOOKS TO
BE 18Z SAT THROUGH 03Z SUN. THERE IS A THREAT FOR THUNDERSTORMS AT
THE TERMINAL OR IN THE VICINITY AFTER 15Z SAT. WEISHAAR
&&

.MARINE...NOT MUCH TO CHANGE IN THE MARINE FORECAST. WEST WIND
CONTINUES TO SLOWLY EASE...GENERALLY 10 TO 15 KT THIS EVENING. WIND
WILL TURN NW TO N LATE TONIGHT AND SAT...BUT SPEEDS TO REMAIN UNDER
15 KT. WARM FRONT MOVES ACROSS THE WATERS SUN...WHICH COULD PRODUCE
SMALL CRAFT ADVISORY LEVEL WIND IN THE NRN WATERS SUN. MODEL
DIFFERENCES GROW BEYOND MON WITH DIMINISHING FORECAST CONFIDENCE.

AS OF 03Z SEAS HOVERING AT OR SLIGHTLY ABOVE 10 FT. LATEST WAVE
GUIDANCE SUGGESTS SEAS DROP BELOW 10 FT BEFORE 06Z TONIGHT.
HOWEVER...WILL LET THE SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS RUN
ITS COURSE THROUGH 06Z. FAIRLY BENIGN SEA CONDITIONS SAT AFTERNOON
THROUGH SUN...WITH HEIGHTS LOWERING TO 5 FT OR SO BY LATE SAT
AFTERNOON. SEAS REMAIN BELOW 10 FEET THROUGH EARLY NEXT WEEK.
WEISHAAR
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT
     THIS EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
     11 PM PDT THIS EVENING.

&&

$$

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 242111
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
210 PM PDT FRI APR 24 2015

.SYNOPSIS...APRIL SHOWERS WILL CONTINUE THROUGH SATURDAY ACROSS
SOUTHWEST WASHINGTON AND NORTHWEST OREGON. COOL UPPER LEVEL LOW
PRESSURE WILL MOVE ACROSS WA SAT AND OFF TO THE E SUN. HIGH
PRESSURE WILL BUILD IN FROM THE SOUTH FOR DRIER AND MUCH WARMER
WEATHER MONDAY...POSSIBLY LINGERING INTO TUESDAY AS WELL. THE
NEXT COLD FRONT MAY BRING MORE SHOWERS BY THE MIDDLE OF NEXT WEEK.
&&

.SHORT TERM...SHOWERS WERE WIDESPREAD OVER THE FORECAST AREA FRI
AFTERNOON WITH WATER VAPOR PICTURES SHOWING AN UPPER LOW NEAR
VANCOUVER ISLAND. MODELS CONTINUE TO SHOW THIS LOW  DRIFTING SE
ACROSS WA TONIGHT AND SAT...BEFORE FINALLY MOVING E SUN. AS
SUGGESTED BY THE 12Z SLE SOUNDING...RADAR HAS SHOWN THE SHOWERS TO
BE RATHER SHALLOW WITH TOPS UNDER 20K FT. SNOW SHOWERS IN THE
CASCADES HAVE GENERALLY BEEN IN THE LIGHT SIDE...ON THE ORDER OF 1
TO 3 INCHES. A LOW LEVEL ONSHORE FLOW HELPED TO FEED THE
SHOWERS...BUT THE ONSHORE FLOW WEAKENS CONSIDERABLY TONIGHT AND SAT.
GFS AND ECMWF INDICATE DEEPER INSTABILITY FOR SAT AS THE COLD UPPER
LOW MOVES CLOSER. WHILE MODELS ALL SEEM TO SUGGEST THE SHOWERS
BECOMING LESS WIDESPREAD LATER TONIGHT AND SAT...THE DEEPER
INSTABILITY SUGGESTS INCLUDING A SLIGHT CHANCE FOR THUNDER SUN EVEN
AS POPS DIMINISH. WHAT APPEARS TO BE THE FINAL PROMINIENT SHORTWAVE
ASSOCIATED WITH THE CLOSED LOW MOVES ACROSS THE AREA EARLY SAT
AFTERNOON. FOLLOWING THIS WAVE POPS EXPECTED TO DROP OFF QUICKLY AS
THE UPPER RIDGE BEGINS TO BUILD IN AND AIR MASS STABILIZES.

MODELS OVER THE PAST FEW DAYS HAVE VARIED CONSIDERABLY ON HOW FAR S
THE IMPACTS OF A WARM FRONT WOULD EXTEND SUN AND SUN NIGHT. LATEST
RUNS OF GFS AND NAM JUST CLIP THE NW CORNER OF THE FORECAST AREA SUN
WITH QPF. EC AND UK EXTEND THE PRECIPITATION FURTHER S...BUT EVEN
THESE MODELS ON THE 12Z RUNS ARE TRENDING TOWARDS LOWER POPS. GIVEN
CURRENT TRENDS...WILL BACK OFF ON POPS A BIT MORE FOR SUN AND
SUN NIGHT ESP ACROSS THE S PART OF THE FORECAST AREA.

BY MON MODELS IN GOOD AGREEMENT WITH BUILDING A FAIRLY STRONG IF
TRANSIENT RIDGE OVER THE REGION. H8 TEMPS ON THE ORDER OF 14 DEG C
ON BOTH GFS AND EC SUGGEST HIGH TEMPS MON MAY APPROACH 80 IN THE
INLAND VALLEYS.

.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...MODELS ARE STILL SOMEWHAT
INCONSISTENT WITH THE TIMING OF SYSTEMS FORECAST TO MOVE THROUGH
NEXT WEEK.  RIDGE OVER THE PACIFIC NORTHWEST GETS PUSHED OFF TO THE
EAST MONDAY NIGHT INTO TUESDAY AS AN UPPER-LEVEL TROUGH MOVES
ONSHORE AND STALLS OVER THE AREA. A COLD FRONT ASSOCIATED WITH THIS
UPPER-LEVEL TROUGH MOVES THROUGH DURING THE DAY ON TUESDAY...WITH
THE ECMWF BRINGING THE FRONT THROUGH DURING THE MORNING ON TUESDAY
AND THE GFS BRINGING THE FRONT THROUGH LATER IN THE
AFTERNOON/EVENING ON TUESDAY. THE ECMWF SEEMS TO BRING THE FRONT IN
A LITTLE TOO FAST...WHILE THE GFS MIGHT BE TOO SLOW...SO EXPECT THE
FRONT TO MOVE THROUGH SOMETIME MIDDAY ON TUESDAY. COOLED TEMPS A BIT
ON TUESDAY AS EITHER AN INCREASE IN CLOUDS AHEAD OF THE FRONT...OR
CLOUDS AND RAIN WITH THE FRONTAL SYSTEM WILL KEEP TEMPERATURES FROM
REACHING AS WARM AS PREVIOUSLY FORECAST. UNSTABLE AIRMASS UNDER
UPPER LEVEL TROUGHING BEHIND THE FRONT TUESDAY NIGHT INTO WEDNESDAY
WILL LIKELY KEEP SCATTERED SHOWERS ACROSS THE AREA UNTIL WEDNESDAY
EVENING...WHEN SHOWERS SHOULD BEGIN TO TAPER OFF EXCEPT MAYBE IN THE
CASCADES AND NORTHERN COAST/COAST RANGE.

A SHORTWAVE ON THE BACK SIDE OF THE STALLED UPPER-LEVEL TROUGH OVER
OUR AREA WILL MOVE THROUGH LATER NEXT WEEK...WITH INCONSISTENCY
BETWEEN THE GFS AND ECMWF ON THE TIMING OF THIS SYSTEM AS WELL.
RIGHT NOW...MODELS SUGGEST THAT THIS FRONT WILL MOVE THROUGH
SOMETIME ON THURSDAY...BRINGING MORE RAIN FOR THURSDAY INTO FRIDAY.
-MCCOY
&&

.AVIATION...MOSTLY VFR CONTINUES NEXT 24 HRS IN SCATTERED
SHOWERS. OCCASIONAL MVFR CIGS AND VIS IN HEAVIER SHOWERS. SHOWERS
WILL BE MOST ACTIVE NORTH OF KSLE. THERE WILL BE A SLIGHT CHANCE
OF THUNDERSTORM IN THE KAST AREA AFTER 06Z SAT...AND OVER INLAND
VALLEYS AFTER 14Z SAT.

KPDX AND APPROACHES...VFR WILL PREVAIL IN POST FRONTAL SHOWERS
NEXT 24 HRS. BRIEF MVFR CIGS...AND OCCASIONALLY VIS...POSSIBLE
IN HEAVIER SHOWERS. THERE IS A THREAT FOR ISOLATED THUNDERSTORMS
TO BE IN THE VICINITY BETWEEN 14Z-20Z SAT MORNING. /27

&&

.MARINE...WEST WINDS HAVE FALLEN BELOW ADVISORY CRITERIA THIS
AFTERNOON WITH WINDS 10 TO 15 KT. WINDS WILL REMAIN BELOW SMALL
CRAFT ADVISORY CRITERIA THROUGH LATE SAT...THEN PICK UP AGAIN WITH
THE APPROACH OF AN INCOMING WARM FRONT BY SUN. THE FRONT STALLS
OVER THE NORTHERN MARINE ZONES BEFORE LIFTING NORTH EARLY MON...SO
THE MAIN THREAT FOR ADVISORY LEVEL WIND GUSTS WILL BE OVER THE
NORTHERN COASTAL WATERS. AFTER MONDAY MODEL DIFFERENCES GROW AND
FORECAST CONFIDENCE DECREASES.

SEAS PEAKED BETWEEN 15 TO 17 FT EARLIER TODAY...WITH THE US COAST
GUARD REPORTING 16 TO 18 FT SEAS AT THE MAIN CHANNEL OF THE
COLUMBIA RIVER BAR. SEAS WILL CONTINUE TO FALL THROUGH THIS
EVENING...HOVERING AROUND 10 FT THROUGH AT LEAST 04-06Z SAT. SEAS
REMAIN BELOW 10 FEET THROUGH EARLY NEXT WEEK. /27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER TO FLORENCE
     OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 11
     PM PDT THIS EVENING.
&&

$$

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 242111
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
210 PM PDT FRI APR 24 2015

.SYNOPSIS...APRIL SHOWERS WILL CONTINUE THROUGH SATURDAY ACROSS
SOUTHWEST WASHINGTON AND NORTHWEST OREGON. COOL UPPER LEVEL LOW
PRESSURE WILL MOVE ACROSS WA SAT AND OFF TO THE E SUN. HIGH
PRESSURE WILL BUILD IN FROM THE SOUTH FOR DRIER AND MUCH WARMER
WEATHER MONDAY...POSSIBLY LINGERING INTO TUESDAY AS WELL. THE
NEXT COLD FRONT MAY BRING MORE SHOWERS BY THE MIDDLE OF NEXT WEEK.
&&

.SHORT TERM...SHOWERS WERE WIDESPREAD OVER THE FORECAST AREA FRI
AFTERNOON WITH WATER VAPOR PICTURES SHOWING AN UPPER LOW NEAR
VANCOUVER ISLAND. MODELS CONTINUE TO SHOW THIS LOW  DRIFTING SE
ACROSS WA TONIGHT AND SAT...BEFORE FINALLY MOVING E SUN. AS
SUGGESTED BY THE 12Z SLE SOUNDING...RADAR HAS SHOWN THE SHOWERS TO
BE RATHER SHALLOW WITH TOPS UNDER 20K FT. SNOW SHOWERS IN THE
CASCADES HAVE GENERALLY BEEN IN THE LIGHT SIDE...ON THE ORDER OF 1
TO 3 INCHES. A LOW LEVEL ONSHORE FLOW HELPED TO FEED THE
SHOWERS...BUT THE ONSHORE FLOW WEAKENS CONSIDERABLY TONIGHT AND SAT.
GFS AND ECMWF INDICATE DEEPER INSTABILITY FOR SAT AS THE COLD UPPER
LOW MOVES CLOSER. WHILE MODELS ALL SEEM TO SUGGEST THE SHOWERS
BECOMING LESS WIDESPREAD LATER TONIGHT AND SAT...THE DEEPER
INSTABILITY SUGGESTS INCLUDING A SLIGHT CHANCE FOR THUNDER SUN EVEN
AS POPS DIMINISH. WHAT APPEARS TO BE THE FINAL PROMINIENT SHORTWAVE
ASSOCIATED WITH THE CLOSED LOW MOVES ACROSS THE AREA EARLY SAT
AFTERNOON. FOLLOWING THIS WAVE POPS EXPECTED TO DROP OFF QUICKLY AS
THE UPPER RIDGE BEGINS TO BUILD IN AND AIR MASS STABILIZES.

MODELS OVER THE PAST FEW DAYS HAVE VARIED CONSIDERABLY ON HOW FAR S
THE IMPACTS OF A WARM FRONT WOULD EXTEND SUN AND SUN NIGHT. LATEST
RUNS OF GFS AND NAM JUST CLIP THE NW CORNER OF THE FORECAST AREA SUN
WITH QPF. EC AND UK EXTEND THE PRECIPITATION FURTHER S...BUT EVEN
THESE MODELS ON THE 12Z RUNS ARE TRENDING TOWARDS LOWER POPS. GIVEN
CURRENT TRENDS...WILL BACK OFF ON POPS A BIT MORE FOR SUN AND
SUN NIGHT ESP ACROSS THE S PART OF THE FORECAST AREA.

BY MON MODELS IN GOOD AGREEMENT WITH BUILDING A FAIRLY STRONG IF
TRANSIENT RIDGE OVER THE REGION. H8 TEMPS ON THE ORDER OF 14 DEG C
ON BOTH GFS AND EC SUGGEST HIGH TEMPS MON MAY APPROACH 80 IN THE
INLAND VALLEYS.

.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...MODELS ARE STILL SOMEWHAT
INCONSISTENT WITH THE TIMING OF SYSTEMS FORECAST TO MOVE THROUGH
NEXT WEEK.  RIDGE OVER THE PACIFIC NORTHWEST GETS PUSHED OFF TO THE
EAST MONDAY NIGHT INTO TUESDAY AS AN UPPER-LEVEL TROUGH MOVES
ONSHORE AND STALLS OVER THE AREA. A COLD FRONT ASSOCIATED WITH THIS
UPPER-LEVEL TROUGH MOVES THROUGH DURING THE DAY ON TUESDAY...WITH
THE ECMWF BRINGING THE FRONT THROUGH DURING THE MORNING ON TUESDAY
AND THE GFS BRINGING THE FRONT THROUGH LATER IN THE
AFTERNOON/EVENING ON TUESDAY. THE ECMWF SEEMS TO BRING THE FRONT IN
A LITTLE TOO FAST...WHILE THE GFS MIGHT BE TOO SLOW...SO EXPECT THE
FRONT TO MOVE THROUGH SOMETIME MIDDAY ON TUESDAY. COOLED TEMPS A BIT
ON TUESDAY AS EITHER AN INCREASE IN CLOUDS AHEAD OF THE FRONT...OR
CLOUDS AND RAIN WITH THE FRONTAL SYSTEM WILL KEEP TEMPERATURES FROM
REACHING AS WARM AS PREVIOUSLY FORECAST. UNSTABLE AIRMASS UNDER
UPPER LEVEL TROUGHING BEHIND THE FRONT TUESDAY NIGHT INTO WEDNESDAY
WILL LIKELY KEEP SCATTERED SHOWERS ACROSS THE AREA UNTIL WEDNESDAY
EVENING...WHEN SHOWERS SHOULD BEGIN TO TAPER OFF EXCEPT MAYBE IN THE
CASCADES AND NORTHERN COAST/COAST RANGE.

A SHORTWAVE ON THE BACK SIDE OF THE STALLED UPPER-LEVEL TROUGH OVER
OUR AREA WILL MOVE THROUGH LATER NEXT WEEK...WITH INCONSISTENCY
BETWEEN THE GFS AND ECMWF ON THE TIMING OF THIS SYSTEM AS WELL.
RIGHT NOW...MODELS SUGGEST THAT THIS FRONT WILL MOVE THROUGH
SOMETIME ON THURSDAY...BRINGING MORE RAIN FOR THURSDAY INTO FRIDAY.
-MCCOY
&&

.AVIATION...MOSTLY VFR CONTINUES NEXT 24 HRS IN SCATTERED
SHOWERS. OCCASIONAL MVFR CIGS AND VIS IN HEAVIER SHOWERS. SHOWERS
WILL BE MOST ACTIVE NORTH OF KSLE. THERE WILL BE A SLIGHT CHANCE
OF THUNDERSTORM IN THE KAST AREA AFTER 06Z SAT...AND OVER INLAND
VALLEYS AFTER 14Z SAT.

KPDX AND APPROACHES...VFR WILL PREVAIL IN POST FRONTAL SHOWERS
NEXT 24 HRS. BRIEF MVFR CIGS...AND OCCASIONALLY VIS...POSSIBLE
IN HEAVIER SHOWERS. THERE IS A THREAT FOR ISOLATED THUNDERSTORMS
TO BE IN THE VICINITY BETWEEN 14Z-20Z SAT MORNING. /27

&&

.MARINE...WEST WINDS HAVE FALLEN BELOW ADVISORY CRITERIA THIS
AFTERNOON WITH WINDS 10 TO 15 KT. WINDS WILL REMAIN BELOW SMALL
CRAFT ADVISORY CRITERIA THROUGH LATE SAT...THEN PICK UP AGAIN WITH
THE APPROACH OF AN INCOMING WARM FRONT BY SUN. THE FRONT STALLS
OVER THE NORTHERN MARINE ZONES BEFORE LIFTING NORTH EARLY MON...SO
THE MAIN THREAT FOR ADVISORY LEVEL WIND GUSTS WILL BE OVER THE
NORTHERN COASTAL WATERS. AFTER MONDAY MODEL DIFFERENCES GROW AND
FORECAST CONFIDENCE DECREASES.

SEAS PEAKED BETWEEN 15 TO 17 FT EARLIER TODAY...WITH THE US COAST
GUARD REPORTING 16 TO 18 FT SEAS AT THE MAIN CHANNEL OF THE
COLUMBIA RIVER BAR. SEAS WILL CONTINUE TO FALL THROUGH THIS
EVENING...HOVERING AROUND 10 FT THROUGH AT LEAST 04-06Z SAT. SEAS
REMAIN BELOW 10 FEET THROUGH EARLY NEXT WEEK. /27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER TO FLORENCE
     OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 11
     PM PDT THIS EVENING.
&&

$$

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 241555
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
900 AM PDT FRI APR 24 2015

.SYNOPSIS...APRIL SHOWERS WILL CONTINUE THROUGH SATURDAY ACROSS
SOUTHWEST WASHINGTON AND NORTHWEST OREGON. COOL UPPER LEVEL LOW
PRESSURE AND MOIST ONSHORE FLOW WILL COMBINE TO KEEP THE AIR MASS
UNSTABLE ENOUGH FOR SHOWERS TO PERSIST. THE CORE OF THE UPPER LOW
WILL SWING THROUGH WASHINGTON SATURDAY...POSSIBLY CLIPPING AREAS
SALEM NORTH WITH A COUPLE THUNDERSTORMS AND SMALL HAIL. A WARM FRONT
MAY CLIP SOME OF THE FORECAST AREA WITH LIGHT RAIN SUNDAY...THEN HIGH
PRESSURE WILL BUILD IN FROM THE SOUTH FOR DRIER AND MUCH WARMER
WEATHER MONDAY...POSSIBLY TUESDAY AS WELL. THE NEXT COLD FRONT MAY
BRING MORE SHOWERS BY THE MIDDLE OF NEXT WEEK.

&&

.SHORT TERM...THE UPPER LEVEL LOW SEEN IN WATER VAPOR PICTURES ALONG
THE S BC COAST THIS MORNING IS EXPECTED TO SLOWLY ROTATE THROUGH THE
PACIFIC NW THROUGH SAT...MOVING INTO EASTERN WA BY SAT AFTERNOON.
THIS WILL KEEP A COOL AND UNSTABLE AIR MASS OVER THE REGION THROUGH
SAT. SHOWERS TODAY WILL BE AIDED BY A WEAK SHORTWAVE...EVIDENT IN WV
IMAGERY JUST OFF THE COAST...ROTATING THROUGH AS WELL AS A MODEST
WESTERLY ONSHORE FLOW IN THE LOW LEVELS. GFS BUFR SOUNDINGS INDICATE
THE INSTABILITY OVER THE N INTERIOR MAY BE DEEP ENOUGH TO SUPPORT A
THUNDER THREAT WITH CAPE EXTENDING UP TO NEAR -20C...BUT WITH OTHER
MODELS NOT INDICATING THE DEEPER CONVECTIVE THREAT AND NO LIGHTNING
OBSERVED OVER THE REGION...WILL KEEP ANY MENTION OF THUNDER OUT FOR
TODAY. COOL AIR MASS WILL KEEP SNOW LEVELS A LITTLE BELOW PASSES
TODAY...WITH A FEW INCHES POSSIBLE AT HIGHER PASSES OR ABOVE.

REMAINDER OF SHORT TERM DISCUSSION UNCHANGED...MODELS SUGGEST THE
CORE OF COLD AIR ALOFT WILL SWING ACROSS WASHINGTON SATURDAY...WITH
AN ASSOCIATED LOBE OF -30 TO -32 DEG C 500 MB TEMPS EXTENDING INTO
NW OREGON AS FAR SOUTH AS SALEM. THIS WILL PROVIDE A BETTER CHANCE
FOR THUNDER ALONG THE COAST SAT MORNING... THEN INLAND DURING THE
AFTERNOON AS THE UPPER TROUGH AXIS PUSHES ONSHORE AND INTO THE
CASCADES. ADDED MENTION OF SMALL HAIL TO THE FCST SAT AS THE DEEPER
CONVECTION WILL BE MORE FAVORABLE TO DEVELOP SMALL HAILSTONES.
HOWEVER THE LOW-LEVEL SHEAR PROFILE IS WEAKER SATURDAY THAN
TODAY...SO THE CHANCE FOR COLD CORE FUNNELS MAY ACTUALLY BE LESS
THAN TODAY DESPITE THE GREATER BUOYANCY.

WARMER TEMPS ALOFT WILL BUILD IN QUICKLY LATER SAT AFTERNOON AND
EVENING...CAPPING OFF ANY CONVECTION. MODELS SHOW HIGH PRESSURE
BUILDING IN FROM THE S-SW AT THAT POINT...SO THE COMBINATION OF AN
INCREASINGLY LOWER CAP...SUBSIDENCE...AND FINALLY THE LOSS OF SOLAR
HEATING TOWARD SUNSET WILL BRING A SWIFT END TO SHOWER ACTIVITY SAT
EVENING. SUNDAY WILL BE A TRANSITION DAY...WITH AN RAPIDLY AMPLIFYING
UPPER RIDGE PUSHING A WARM FRONT SOUTH TO NORTH ACROSS THE
DISTRICT...POSSIBLY BRUSHING OUR CWA WITH MORE LIGHT RAIN... MAINLY
ALONG THE NORTH COAST. STRONG WARM ADVECTION ALOFT WILL FOLLOW...
WITH 850 MB TEMPS RISING FROM ABOUT +4 DEG C SUN AFTERNOON TO +14
DEG C MONDAY PER THE 00Z/06Z GFS. THEREFORE EXPECT A QUICK RETURN TO
MUCH DRIER WEATHER SUN NIGHT/MON WITH TEMPS WELL INTO THE 70S AND
POSSIBLY APPROACHING 80 FOR THE INLAND VALLEYS MONDAY AFTERNOON.
COASTAL AREAS WILL LIKELY REMAIN IN THE 60S MONDAY DUE TO A LACK OF
A DRIVER FOR STRONG OFFSHORE FLOW.  WEAGLE

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK REMARKABLY SIMILAR
AT FIRST GLANCE AND MIGHT LEAD ONE TO A RELATIVELY HIGH DEGREE OF
CONFIDENCE IN THE LATEST EXTENDED FORECAST...RUN TO RUN CONSISTENCY
IN BOTH THE EC AND GFS HAS BEEN POOR TO SAY THE LEAST OVER THE LAST
48 HOURS. WHILE I SUSPECT A STORM SYSTEM WILL BRING AT LEAST SOME
THREAT OF RAIN TO THE AREA TUESDAY OR WEDNESDAY...CONFIDENCE IN THE
DETAILS IS VERY LOW CONSIDERING THE SUBSTANTIAL CHANGES IN THE
SYNOPTIC EVOLUTION AND TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED
DURING THIS PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH
MODELS SUGGEST THERE MAY BE SOME DRYING THEREAFTER...POPS WERE
TRENDED CLOSER TO CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE
FORECAST. /NEUMAN

&&

.AVIATION...VFR CONTINUES NEXT 24 HRS IN SCATTERED SHOWERS.
OCCASIONAL MVFR CIGS IN HEAVIER SHOWERS. SHOWERS WILL BE MOST
ACTIVE NORTH OF KSLE. THERE WILL BE A SLIGHT CHANCE OF
THUNDERSTORM IN THE KAST AREA AFTER 06Z SAT.

KPDX AND APPROACHES...VFR WILL PREVAIL IN POST FRONTAL SHOWERS
NEXT 24 HRS. BRIEF MVFR CIGS POSSIBLE WITH HEAVIER SHOWERS. /27

&&

.MARINE...WEST WINDS WILL GRADUALLY DIMINISH THIS MORNING...SO
WILL LET THE SMALL CRAFT ADVISORY FOR WINDS RUN THROUGH 11 AM.
WINDS WILL CONTINUE TO EASE TONIGHT...REMAINING BELOW CRITERIA
THROUGH SAT. THE NEXT WARM FRONT APPROACHES THE WATERS SAT NIGHT
AND SUN BUT STALLS OVER THE NORTHERN MARINE ZONES BEFORE LIFTING
NORTH EARLY MON. MODELS ARE IN FAIR AGREEMENT WITH THIS HAPPENING.
AFTER MONDAY MODEL DIFFERENCES GROW AND FORECAST CONFIDENCE
DECREASES.

SEAS 12 TO 16 FT WILL CONTINUE THROUGH THIS AFTERNOON...BEFORE
SUBSIDING BELOW 10 FT LATER THIS EVENING. SEAS REMAIN BELOW 10
FEET THROUGH EARLY NEXT WEEK. WILL CONTINUE WITH ROUGH COLUMBIA
RIVER BAR CONDITIONS THROUGH THIS EVENING. /27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM PDT THIS MORNING
     FOR WATERS FROM CAPE SHOALWATER TO CASCADE HEAD FROM 10 TO
     60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER TO FLORENCE
     OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 11
     PM PDT THIS EVENING.
&&

$$

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 241555
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
900 AM PDT FRI APR 24 2015

.SYNOPSIS...APRIL SHOWERS WILL CONTINUE THROUGH SATURDAY ACROSS
SOUTHWEST WASHINGTON AND NORTHWEST OREGON. COOL UPPER LEVEL LOW
PRESSURE AND MOIST ONSHORE FLOW WILL COMBINE TO KEEP THE AIR MASS
UNSTABLE ENOUGH FOR SHOWERS TO PERSIST. THE CORE OF THE UPPER LOW
WILL SWING THROUGH WASHINGTON SATURDAY...POSSIBLY CLIPPING AREAS
SALEM NORTH WITH A COUPLE THUNDERSTORMS AND SMALL HAIL. A WARM FRONT
MAY CLIP SOME OF THE FORECAST AREA WITH LIGHT RAIN SUNDAY...THEN HIGH
PRESSURE WILL BUILD IN FROM THE SOUTH FOR DRIER AND MUCH WARMER
WEATHER MONDAY...POSSIBLY TUESDAY AS WELL. THE NEXT COLD FRONT MAY
BRING MORE SHOWERS BY THE MIDDLE OF NEXT WEEK.

&&

.SHORT TERM...THE UPPER LEVEL LOW SEEN IN WATER VAPOR PICTURES ALONG
THE S BC COAST THIS MORNING IS EXPECTED TO SLOWLY ROTATE THROUGH THE
PACIFIC NW THROUGH SAT...MOVING INTO EASTERN WA BY SAT AFTERNOON.
THIS WILL KEEP A COOL AND UNSTABLE AIR MASS OVER THE REGION THROUGH
SAT. SHOWERS TODAY WILL BE AIDED BY A WEAK SHORTWAVE...EVIDENT IN WV
IMAGERY JUST OFF THE COAST...ROTATING THROUGH AS WELL AS A MODEST
WESTERLY ONSHORE FLOW IN THE LOW LEVELS. GFS BUFR SOUNDINGS INDICATE
THE INSTABILITY OVER THE N INTERIOR MAY BE DEEP ENOUGH TO SUPPORT A
THUNDER THREAT WITH CAPE EXTENDING UP TO NEAR -20C...BUT WITH OTHER
MODELS NOT INDICATING THE DEEPER CONVECTIVE THREAT AND NO LIGHTNING
OBSERVED OVER THE REGION...WILL KEEP ANY MENTION OF THUNDER OUT FOR
TODAY. COOL AIR MASS WILL KEEP SNOW LEVELS A LITTLE BELOW PASSES
TODAY...WITH A FEW INCHES POSSIBLE AT HIGHER PASSES OR ABOVE.

REMAINDER OF SHORT TERM DISCUSSION UNCHANGED...MODELS SUGGEST THE
CORE OF COLD AIR ALOFT WILL SWING ACROSS WASHINGTON SATURDAY...WITH
AN ASSOCIATED LOBE OF -30 TO -32 DEG C 500 MB TEMPS EXTENDING INTO
NW OREGON AS FAR SOUTH AS SALEM. THIS WILL PROVIDE A BETTER CHANCE
FOR THUNDER ALONG THE COAST SAT MORNING... THEN INLAND DURING THE
AFTERNOON AS THE UPPER TROUGH AXIS PUSHES ONSHORE AND INTO THE
CASCADES. ADDED MENTION OF SMALL HAIL TO THE FCST SAT AS THE DEEPER
CONVECTION WILL BE MORE FAVORABLE TO DEVELOP SMALL HAILSTONES.
HOWEVER THE LOW-LEVEL SHEAR PROFILE IS WEAKER SATURDAY THAN
TODAY...SO THE CHANCE FOR COLD CORE FUNNELS MAY ACTUALLY BE LESS
THAN TODAY DESPITE THE GREATER BUOYANCY.

WARMER TEMPS ALOFT WILL BUILD IN QUICKLY LATER SAT AFTERNOON AND
EVENING...CAPPING OFF ANY CONVECTION. MODELS SHOW HIGH PRESSURE
BUILDING IN FROM THE S-SW AT THAT POINT...SO THE COMBINATION OF AN
INCREASINGLY LOWER CAP...SUBSIDENCE...AND FINALLY THE LOSS OF SOLAR
HEATING TOWARD SUNSET WILL BRING A SWIFT END TO SHOWER ACTIVITY SAT
EVENING. SUNDAY WILL BE A TRANSITION DAY...WITH AN RAPIDLY AMPLIFYING
UPPER RIDGE PUSHING A WARM FRONT SOUTH TO NORTH ACROSS THE
DISTRICT...POSSIBLY BRUSHING OUR CWA WITH MORE LIGHT RAIN... MAINLY
ALONG THE NORTH COAST. STRONG WARM ADVECTION ALOFT WILL FOLLOW...
WITH 850 MB TEMPS RISING FROM ABOUT +4 DEG C SUN AFTERNOON TO +14
DEG C MONDAY PER THE 00Z/06Z GFS. THEREFORE EXPECT A QUICK RETURN TO
MUCH DRIER WEATHER SUN NIGHT/MON WITH TEMPS WELL INTO THE 70S AND
POSSIBLY APPROACHING 80 FOR THE INLAND VALLEYS MONDAY AFTERNOON.
COASTAL AREAS WILL LIKELY REMAIN IN THE 60S MONDAY DUE TO A LACK OF
A DRIVER FOR STRONG OFFSHORE FLOW.  WEAGLE

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK REMARKABLY SIMILAR
AT FIRST GLANCE AND MIGHT LEAD ONE TO A RELATIVELY HIGH DEGREE OF
CONFIDENCE IN THE LATEST EXTENDED FORECAST...RUN TO RUN CONSISTENCY
IN BOTH THE EC AND GFS HAS BEEN POOR TO SAY THE LEAST OVER THE LAST
48 HOURS. WHILE I SUSPECT A STORM SYSTEM WILL BRING AT LEAST SOME
THREAT OF RAIN TO THE AREA TUESDAY OR WEDNESDAY...CONFIDENCE IN THE
DETAILS IS VERY LOW CONSIDERING THE SUBSTANTIAL CHANGES IN THE
SYNOPTIC EVOLUTION AND TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED
DURING THIS PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH
MODELS SUGGEST THERE MAY BE SOME DRYING THEREAFTER...POPS WERE
TRENDED CLOSER TO CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE
FORECAST. /NEUMAN

&&

.AVIATION...VFR CONTINUES NEXT 24 HRS IN SCATTERED SHOWERS.
OCCASIONAL MVFR CIGS IN HEAVIER SHOWERS. SHOWERS WILL BE MOST
ACTIVE NORTH OF KSLE. THERE WILL BE A SLIGHT CHANCE OF
THUNDERSTORM IN THE KAST AREA AFTER 06Z SAT.

KPDX AND APPROACHES...VFR WILL PREVAIL IN POST FRONTAL SHOWERS
NEXT 24 HRS. BRIEF MVFR CIGS POSSIBLE WITH HEAVIER SHOWERS. /27

&&

.MARINE...WEST WINDS WILL GRADUALLY DIMINISH THIS MORNING...SO
WILL LET THE SMALL CRAFT ADVISORY FOR WINDS RUN THROUGH 11 AM.
WINDS WILL CONTINUE TO EASE TONIGHT...REMAINING BELOW CRITERIA
THROUGH SAT. THE NEXT WARM FRONT APPROACHES THE WATERS SAT NIGHT
AND SUN BUT STALLS OVER THE NORTHERN MARINE ZONES BEFORE LIFTING
NORTH EARLY MON. MODELS ARE IN FAIR AGREEMENT WITH THIS HAPPENING.
AFTER MONDAY MODEL DIFFERENCES GROW AND FORECAST CONFIDENCE
DECREASES.

SEAS 12 TO 16 FT WILL CONTINUE THROUGH THIS AFTERNOON...BEFORE
SUBSIDING BELOW 10 FT LATER THIS EVENING. SEAS REMAIN BELOW 10
FEET THROUGH EARLY NEXT WEEK. WILL CONTINUE WITH ROUGH COLUMBIA
RIVER BAR CONDITIONS THROUGH THIS EVENING. /27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM PDT THIS MORNING
     FOR WATERS FROM CAPE SHOALWATER TO CASCADE HEAD FROM 10 TO
     60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER TO FLORENCE
     OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 11
     PM PDT THIS EVENING.
&&

$$

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 241555
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
900 AM PDT FRI APR 24 2015

.SYNOPSIS...APRIL SHOWERS WILL CONTINUE THROUGH SATURDAY ACROSS
SOUTHWEST WASHINGTON AND NORTHWEST OREGON. COOL UPPER LEVEL LOW
PRESSURE AND MOIST ONSHORE FLOW WILL COMBINE TO KEEP THE AIR MASS
UNSTABLE ENOUGH FOR SHOWERS TO PERSIST. THE CORE OF THE UPPER LOW
WILL SWING THROUGH WASHINGTON SATURDAY...POSSIBLY CLIPPING AREAS
SALEM NORTH WITH A COUPLE THUNDERSTORMS AND SMALL HAIL. A WARM FRONT
MAY CLIP SOME OF THE FORECAST AREA WITH LIGHT RAIN SUNDAY...THEN HIGH
PRESSURE WILL BUILD IN FROM THE SOUTH FOR DRIER AND MUCH WARMER
WEATHER MONDAY...POSSIBLY TUESDAY AS WELL. THE NEXT COLD FRONT MAY
BRING MORE SHOWERS BY THE MIDDLE OF NEXT WEEK.

&&

.SHORT TERM...THE UPPER LEVEL LOW SEEN IN WATER VAPOR PICTURES ALONG
THE S BC COAST THIS MORNING IS EXPECTED TO SLOWLY ROTATE THROUGH THE
PACIFIC NW THROUGH SAT...MOVING INTO EASTERN WA BY SAT AFTERNOON.
THIS WILL KEEP A COOL AND UNSTABLE AIR MASS OVER THE REGION THROUGH
SAT. SHOWERS TODAY WILL BE AIDED BY A WEAK SHORTWAVE...EVIDENT IN WV
IMAGERY JUST OFF THE COAST...ROTATING THROUGH AS WELL AS A MODEST
WESTERLY ONSHORE FLOW IN THE LOW LEVELS. GFS BUFR SOUNDINGS INDICATE
THE INSTABILITY OVER THE N INTERIOR MAY BE DEEP ENOUGH TO SUPPORT A
THUNDER THREAT WITH CAPE EXTENDING UP TO NEAR -20C...BUT WITH OTHER
MODELS NOT INDICATING THE DEEPER CONVECTIVE THREAT AND NO LIGHTNING
OBSERVED OVER THE REGION...WILL KEEP ANY MENTION OF THUNDER OUT FOR
TODAY. COOL AIR MASS WILL KEEP SNOW LEVELS A LITTLE BELOW PASSES
TODAY...WITH A FEW INCHES POSSIBLE AT HIGHER PASSES OR ABOVE.

REMAINDER OF SHORT TERM DISCUSSION UNCHANGED...MODELS SUGGEST THE
CORE OF COLD AIR ALOFT WILL SWING ACROSS WASHINGTON SATURDAY...WITH
AN ASSOCIATED LOBE OF -30 TO -32 DEG C 500 MB TEMPS EXTENDING INTO
NW OREGON AS FAR SOUTH AS SALEM. THIS WILL PROVIDE A BETTER CHANCE
FOR THUNDER ALONG THE COAST SAT MORNING... THEN INLAND DURING THE
AFTERNOON AS THE UPPER TROUGH AXIS PUSHES ONSHORE AND INTO THE
CASCADES. ADDED MENTION OF SMALL HAIL TO THE FCST SAT AS THE DEEPER
CONVECTION WILL BE MORE FAVORABLE TO DEVELOP SMALL HAILSTONES.
HOWEVER THE LOW-LEVEL SHEAR PROFILE IS WEAKER SATURDAY THAN
TODAY...SO THE CHANCE FOR COLD CORE FUNNELS MAY ACTUALLY BE LESS
THAN TODAY DESPITE THE GREATER BUOYANCY.

WARMER TEMPS ALOFT WILL BUILD IN QUICKLY LATER SAT AFTERNOON AND
EVENING...CAPPING OFF ANY CONVECTION. MODELS SHOW HIGH PRESSURE
BUILDING IN FROM THE S-SW AT THAT POINT...SO THE COMBINATION OF AN
INCREASINGLY LOWER CAP...SUBSIDENCE...AND FINALLY THE LOSS OF SOLAR
HEATING TOWARD SUNSET WILL BRING A SWIFT END TO SHOWER ACTIVITY SAT
EVENING. SUNDAY WILL BE A TRANSITION DAY...WITH AN RAPIDLY AMPLIFYING
UPPER RIDGE PUSHING A WARM FRONT SOUTH TO NORTH ACROSS THE
DISTRICT...POSSIBLY BRUSHING OUR CWA WITH MORE LIGHT RAIN... MAINLY
ALONG THE NORTH COAST. STRONG WARM ADVECTION ALOFT WILL FOLLOW...
WITH 850 MB TEMPS RISING FROM ABOUT +4 DEG C SUN AFTERNOON TO +14
DEG C MONDAY PER THE 00Z/06Z GFS. THEREFORE EXPECT A QUICK RETURN TO
MUCH DRIER WEATHER SUN NIGHT/MON WITH TEMPS WELL INTO THE 70S AND
POSSIBLY APPROACHING 80 FOR THE INLAND VALLEYS MONDAY AFTERNOON.
COASTAL AREAS WILL LIKELY REMAIN IN THE 60S MONDAY DUE TO A LACK OF
A DRIVER FOR STRONG OFFSHORE FLOW.  WEAGLE

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK REMARKABLY SIMILAR
AT FIRST GLANCE AND MIGHT LEAD ONE TO A RELATIVELY HIGH DEGREE OF
CONFIDENCE IN THE LATEST EXTENDED FORECAST...RUN TO RUN CONSISTENCY
IN BOTH THE EC AND GFS HAS BEEN POOR TO SAY THE LEAST OVER THE LAST
48 HOURS. WHILE I SUSPECT A STORM SYSTEM WILL BRING AT LEAST SOME
THREAT OF RAIN TO THE AREA TUESDAY OR WEDNESDAY...CONFIDENCE IN THE
DETAILS IS VERY LOW CONSIDERING THE SUBSTANTIAL CHANGES IN THE
SYNOPTIC EVOLUTION AND TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED
DURING THIS PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH
MODELS SUGGEST THERE MAY BE SOME DRYING THEREAFTER...POPS WERE
TRENDED CLOSER TO CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE
FORECAST. /NEUMAN

&&

.AVIATION...VFR CONTINUES NEXT 24 HRS IN SCATTERED SHOWERS.
OCCASIONAL MVFR CIGS IN HEAVIER SHOWERS. SHOWERS WILL BE MOST
ACTIVE NORTH OF KSLE. THERE WILL BE A SLIGHT CHANCE OF
THUNDERSTORM IN THE KAST AREA AFTER 06Z SAT.

KPDX AND APPROACHES...VFR WILL PREVAIL IN POST FRONTAL SHOWERS
NEXT 24 HRS. BRIEF MVFR CIGS POSSIBLE WITH HEAVIER SHOWERS. /27

&&

.MARINE...WEST WINDS WILL GRADUALLY DIMINISH THIS MORNING...SO
WILL LET THE SMALL CRAFT ADVISORY FOR WINDS RUN THROUGH 11 AM.
WINDS WILL CONTINUE TO EASE TONIGHT...REMAINING BELOW CRITERIA
THROUGH SAT. THE NEXT WARM FRONT APPROACHES THE WATERS SAT NIGHT
AND SUN BUT STALLS OVER THE NORTHERN MARINE ZONES BEFORE LIFTING
NORTH EARLY MON. MODELS ARE IN FAIR AGREEMENT WITH THIS HAPPENING.
AFTER MONDAY MODEL DIFFERENCES GROW AND FORECAST CONFIDENCE
DECREASES.

SEAS 12 TO 16 FT WILL CONTINUE THROUGH THIS AFTERNOON...BEFORE
SUBSIDING BELOW 10 FT LATER THIS EVENING. SEAS REMAIN BELOW 10
FEET THROUGH EARLY NEXT WEEK. WILL CONTINUE WITH ROUGH COLUMBIA
RIVER BAR CONDITIONS THROUGH THIS EVENING. /27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM PDT THIS MORNING
     FOR WATERS FROM CAPE SHOALWATER TO CASCADE HEAD FROM 10 TO
     60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER TO FLORENCE
     OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 11
     PM PDT THIS EVENING.
&&

$$

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 241555
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
900 AM PDT FRI APR 24 2015

.SYNOPSIS...APRIL SHOWERS WILL CONTINUE THROUGH SATURDAY ACROSS
SOUTHWEST WASHINGTON AND NORTHWEST OREGON. COOL UPPER LEVEL LOW
PRESSURE AND MOIST ONSHORE FLOW WILL COMBINE TO KEEP THE AIR MASS
UNSTABLE ENOUGH FOR SHOWERS TO PERSIST. THE CORE OF THE UPPER LOW
WILL SWING THROUGH WASHINGTON SATURDAY...POSSIBLY CLIPPING AREAS
SALEM NORTH WITH A COUPLE THUNDERSTORMS AND SMALL HAIL. A WARM FRONT
MAY CLIP SOME OF THE FORECAST AREA WITH LIGHT RAIN SUNDAY...THEN HIGH
PRESSURE WILL BUILD IN FROM THE SOUTH FOR DRIER AND MUCH WARMER
WEATHER MONDAY...POSSIBLY TUESDAY AS WELL. THE NEXT COLD FRONT MAY
BRING MORE SHOWERS BY THE MIDDLE OF NEXT WEEK.

&&

.SHORT TERM...THE UPPER LEVEL LOW SEEN IN WATER VAPOR PICTURES ALONG
THE S BC COAST THIS MORNING IS EXPECTED TO SLOWLY ROTATE THROUGH THE
PACIFIC NW THROUGH SAT...MOVING INTO EASTERN WA BY SAT AFTERNOON.
THIS WILL KEEP A COOL AND UNSTABLE AIR MASS OVER THE REGION THROUGH
SAT. SHOWERS TODAY WILL BE AIDED BY A WEAK SHORTWAVE...EVIDENT IN WV
IMAGERY JUST OFF THE COAST...ROTATING THROUGH AS WELL AS A MODEST
WESTERLY ONSHORE FLOW IN THE LOW LEVELS. GFS BUFR SOUNDINGS INDICATE
THE INSTABILITY OVER THE N INTERIOR MAY BE DEEP ENOUGH TO SUPPORT A
THUNDER THREAT WITH CAPE EXTENDING UP TO NEAR -20C...BUT WITH OTHER
MODELS NOT INDICATING THE DEEPER CONVECTIVE THREAT AND NO LIGHTNING
OBSERVED OVER THE REGION...WILL KEEP ANY MENTION OF THUNDER OUT FOR
TODAY. COOL AIR MASS WILL KEEP SNOW LEVELS A LITTLE BELOW PASSES
TODAY...WITH A FEW INCHES POSSIBLE AT HIGHER PASSES OR ABOVE.

REMAINDER OF SHORT TERM DISCUSSION UNCHANGED...MODELS SUGGEST THE
CORE OF COLD AIR ALOFT WILL SWING ACROSS WASHINGTON SATURDAY...WITH
AN ASSOCIATED LOBE OF -30 TO -32 DEG C 500 MB TEMPS EXTENDING INTO
NW OREGON AS FAR SOUTH AS SALEM. THIS WILL PROVIDE A BETTER CHANCE
FOR THUNDER ALONG THE COAST SAT MORNING... THEN INLAND DURING THE
AFTERNOON AS THE UPPER TROUGH AXIS PUSHES ONSHORE AND INTO THE
CASCADES. ADDED MENTION OF SMALL HAIL TO THE FCST SAT AS THE DEEPER
CONVECTION WILL BE MORE FAVORABLE TO DEVELOP SMALL HAILSTONES.
HOWEVER THE LOW-LEVEL SHEAR PROFILE IS WEAKER SATURDAY THAN
TODAY...SO THE CHANCE FOR COLD CORE FUNNELS MAY ACTUALLY BE LESS
THAN TODAY DESPITE THE GREATER BUOYANCY.

WARMER TEMPS ALOFT WILL BUILD IN QUICKLY LATER SAT AFTERNOON AND
EVENING...CAPPING OFF ANY CONVECTION. MODELS SHOW HIGH PRESSURE
BUILDING IN FROM THE S-SW AT THAT POINT...SO THE COMBINATION OF AN
INCREASINGLY LOWER CAP...SUBSIDENCE...AND FINALLY THE LOSS OF SOLAR
HEATING TOWARD SUNSET WILL BRING A SWIFT END TO SHOWER ACTIVITY SAT
EVENING. SUNDAY WILL BE A TRANSITION DAY...WITH AN RAPIDLY AMPLIFYING
UPPER RIDGE PUSHING A WARM FRONT SOUTH TO NORTH ACROSS THE
DISTRICT...POSSIBLY BRUSHING OUR CWA WITH MORE LIGHT RAIN... MAINLY
ALONG THE NORTH COAST. STRONG WARM ADVECTION ALOFT WILL FOLLOW...
WITH 850 MB TEMPS RISING FROM ABOUT +4 DEG C SUN AFTERNOON TO +14
DEG C MONDAY PER THE 00Z/06Z GFS. THEREFORE EXPECT A QUICK RETURN TO
MUCH DRIER WEATHER SUN NIGHT/MON WITH TEMPS WELL INTO THE 70S AND
POSSIBLY APPROACHING 80 FOR THE INLAND VALLEYS MONDAY AFTERNOON.
COASTAL AREAS WILL LIKELY REMAIN IN THE 60S MONDAY DUE TO A LACK OF
A DRIVER FOR STRONG OFFSHORE FLOW.  WEAGLE

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK REMARKABLY SIMILAR
AT FIRST GLANCE AND MIGHT LEAD ONE TO A RELATIVELY HIGH DEGREE OF
CONFIDENCE IN THE LATEST EXTENDED FORECAST...RUN TO RUN CONSISTENCY
IN BOTH THE EC AND GFS HAS BEEN POOR TO SAY THE LEAST OVER THE LAST
48 HOURS. WHILE I SUSPECT A STORM SYSTEM WILL BRING AT LEAST SOME
THREAT OF RAIN TO THE AREA TUESDAY OR WEDNESDAY...CONFIDENCE IN THE
DETAILS IS VERY LOW CONSIDERING THE SUBSTANTIAL CHANGES IN THE
SYNOPTIC EVOLUTION AND TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED
DURING THIS PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH
MODELS SUGGEST THERE MAY BE SOME DRYING THEREAFTER...POPS WERE
TRENDED CLOSER TO CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE
FORECAST. /NEUMAN

&&

.AVIATION...VFR CONTINUES NEXT 24 HRS IN SCATTERED SHOWERS.
OCCASIONAL MVFR CIGS IN HEAVIER SHOWERS. SHOWERS WILL BE MOST
ACTIVE NORTH OF KSLE. THERE WILL BE A SLIGHT CHANCE OF
THUNDERSTORM IN THE KAST AREA AFTER 06Z SAT.

KPDX AND APPROACHES...VFR WILL PREVAIL IN POST FRONTAL SHOWERS
NEXT 24 HRS. BRIEF MVFR CIGS POSSIBLE WITH HEAVIER SHOWERS. /27

&&

.MARINE...WEST WINDS WILL GRADUALLY DIMINISH THIS MORNING...SO
WILL LET THE SMALL CRAFT ADVISORY FOR WINDS RUN THROUGH 11 AM.
WINDS WILL CONTINUE TO EASE TONIGHT...REMAINING BELOW CRITERIA
THROUGH SAT. THE NEXT WARM FRONT APPROACHES THE WATERS SAT NIGHT
AND SUN BUT STALLS OVER THE NORTHERN MARINE ZONES BEFORE LIFTING
NORTH EARLY MON. MODELS ARE IN FAIR AGREEMENT WITH THIS HAPPENING.
AFTER MONDAY MODEL DIFFERENCES GROW AND FORECAST CONFIDENCE
DECREASES.

SEAS 12 TO 16 FT WILL CONTINUE THROUGH THIS AFTERNOON...BEFORE
SUBSIDING BELOW 10 FT LATER THIS EVENING. SEAS REMAIN BELOW 10
FEET THROUGH EARLY NEXT WEEK. WILL CONTINUE WITH ROUGH COLUMBIA
RIVER BAR CONDITIONS THROUGH THIS EVENING. /27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM PDT THIS MORNING
     FOR WATERS FROM CAPE SHOALWATER TO CASCADE HEAD FROM 10 TO
     60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER TO FLORENCE
     OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 11
     PM PDT THIS EVENING.
&&

$$

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 241045
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
344 AM PDT FRI APR 24 2015

.SYNOPSIS...APRIL SHOWERS WILL CONTINUE THROUGH SATURDAY ACROSS
SOUTHWEST WASHINGTON AND NORTHWEST OREGON. COOL UPPER LEVEL LOW
PRESSURE AND MOIST ONSHORE FLOW WILL COMBINE TO KEEP THE AIR MASS
UNSTABLE ENOUGH FOR SHOWERS TO PERSIST. THE CORE OF THE UPPER LOW
WILL SWING THROUGH WASHINGTON SATURDAY...POSSIBLY CLIPPING AREAS
SALEM NORTH WITH A COUPLE THUNDERSTORMS AND SMALL HAIL. A WARM FRONT
MAY CLIP SOME OF THE FORECAST AREA WITH LIGHT RAIN SUNDAY...THEN HIGH
PRESSURE WILL BUILD IN FROM THE SOUTH FOR DRIER AND MUCH WARMER
WEATHER MONDAY...POSSIBLY TUESDAY AS WELL. THE NEXT COLD FRONT MAY
BRING MORE SHOWERS BY THE MIDDLE OF NEXT WEEK.

&&

.SHORT TERM...TODAY THROUGH MONDAY...WATER VAPOR IMAGERY INDICATES A
BROAD UPPER LEVEL LOW CENTERED NEAR VANCOUVER ISLAND...WITH A
CIRCULATION THAT EXPANDS ACROSS MUCH OF THE AREA BETWEEN BRITISH
COLUMBIA AND OREGON. THIS IS GUIDING A STEADY STREAM OF ONSHORE FLOW
INTO SW WA/NW OR...WITH NUMEROUS SHOWERS MOVING ACROSS THE AREA AS A
RESULT. THIS WILL CONTINUE TO BE THE CASE THROUGH SATURDAY. THE COOL
AIR MASS WILL KEEP SNOW LEVELS NEAR OR JUST BELOW THE CASCADE
PASSES...WITH A FEW INCHES OF NEW SNOW POSSIBLE FOR THE SKI RESORTS.
STRONG APRIL SUNSHINE SHOULD KEEP THE ROADS MAINLY WET ON THE PASSES
DURING THE DAY...BUT ACCUMULATING SNOW COULD MAKE THE PASSES SLICK
THIS MORNING AND AGAIN TONIGHT/SAT MORNING. WILL CONTINUE THE SPS
WHICH HIGHLIGHTS THIS CONCERN.

ONE LOBE OF VORTICITY IS MOVING ONSHORE ALONG THE WASHINGTON AND
EXTREME NORTHERN OREGON COAST...BRINGING SOME ENHANCEMENT TO THE
SHOWER ACTIVITY. SHOWERS REMAIN SHALLOW...GENERALLY TOPPED NEAR OR
BELOW 10 KFT. THEREFORE FOR THE TIME BEING IT DOES NOT LOOK LIKE
THERE IS ENOUGH INSTABILITY FOR THUNDER OR MUCH IN THE WAY OF SMALL
HAIL...AND MODEL SOUNDINGS INDICATE SHOWERS SHOULD REMAIN CAPPED
BELOW 12-15 KFT THROUGHOUT THE DAY TODAY.

A COUPLE INTERESTING THINGS ABOUT THE NAM BUFR SOUNDINGS FOR
TODAY...THERE IS SOME MODEST LOW-LEVEL DIRECTIONAL SHEAR AND STEEP
LOW-LEVEL LAPSE RATES ARE FCST AS TEMPS WARM INTO THE 50S TODAY.
MEANWHILE LCL/S LOOK LOW...AROUND 2-3 KFT...THIS AFTERNOON. THESE ARE
THE INGREDIENTS THAT OFTEN NEED TO COME TOGETHER TO PRODUCE A COUPLE
COLD CORE FUNNELS ACROSS OUR FORECAST AREA...DESPITE THE FACT IT IS
UNLIKELY FOR CONVECTION TO BE DEEP ENOUGH TO GENERATE THUNDER OR EVEN
MUCH HAIL. THAT SAID...WOULD LIKE TO SEE STRONGER FORCING FOR THE SFC
SOUTHERLY FLOW THIS AFTERNOON BEFORE GETTING MORE CONCERNED ABOUT THE
COLD CORE FUNNEL POSSIBILITY.

MODELS SUGGEST THE CORE OF COLD AIR ALOFT WILL SWING ACROSS
WASHINGTON SATURDAY...WITH AN ASSOCIATED LOBE OF -30 TO -32 DEG C 500
MB TEMPS EXTENDING INTO NW OREGON AS FAR SOUTH AS SALEM. THIS WILL
PROVIDE A BETTER CHANCE FOR THUNDER ALONG THE COAST SAT MORNING...
THEN INLAND DURING THE AFTERNOON AS THE UPPER TROUGH AXIS PUSHES
ONSHORE AND INTO THE CASCADES. ADDED MENTION OF SMALL HAIL TO THE
FCST SAT AS THE DEEPER CONVECTION WILL BE MORE FAVORABLE TO DEVELOP
SMALL HAILSTONES. HOWEVER THE LOW-LEVEL SHEAR PROFILE IS WEAKER
SATURDAY THAN TODAY...SO THE CHANCE FOR COLD CORE FUNNELS MAY
ACTUALLY BE LESS THAN TODAY DESPITE THE GREATER BUOYANCY.

WARMER TEMPS ALOFT WILL BUILD IN QUICKLY LATER SAT AFTERNOON AND
EVENING...CAPPING OFF ANY CONVECTION. MODELS SHOW HIGH PRESSURE
BUILDING IN FROM THE S-SW AT THAT POINT...SO THE COMBINATION OF AN
INCREASINGLY LOWER CAP...SUBSIDENCE...AND FINALLY THE LOSS OF SOLAR
HEATING TOWARD SUNSET WILL BRING A SWIFT END TO SHOWER ACTIVITY SAT
EVENING. SUNDAY WILL BE A TRANSITION DAY...WITH AN RAPIDLY AMPLIFYING
UPPER RIDGE PUSHING A WARM FRONT SOUTH TO NORTH ACROSS THE
DISTRICT...POSSIBLY BRUSHING OUR CWA WITH MORE LIGHT RAIN... MAINLY
ALONG THE NORTH COAST. STRONG WARM ADVECTION ALOFT WILL FOLLOW...
WITH 850 MB TEMPS RISING FROM ABOUT +4 DEG C SUN AFTERNOON TO +14
DEG C MONDAY PER THE 00Z/06Z GFS. THEREFORE EXPECT A QUICK RETURN TO
MUCH DRIER WEATHER SUN NIGHT/MON WITH TEMPS WELL INTO THE 70S AND
POSSIBLY APPROACHING 80 FOR THE INLAND VALLEYS MONDAY AFTERNOON.
COASTAL AREAS WILL LIKELY REMAIN IN THE 60S MONDAY DUE TO A LACK OF
A DRIVER FOR STRONG OFFSHORE FLOW.  WEAGLE

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK REMARKABLY SIMILAR
AT FIRST GLANCE AND MIGHT LEAD ONE TO A RELATIVELY HIGH DEGREE OF
CONFIDENCE IN THE LATEST EXTENDED FORECAST...RUN TO RUN CONSISTENCY
IN BOTH THE EC AND GFS HAS BEEN POOR TO SAY THE LEAST OVER THE LAST
48 HOURS. WHILE I SUSPECT A STORM SYSTEM WILL BRING AT LEAST SOME
THREAT OF RAIN TO THE AREA TUESDAY OR WEDNESDAY...CONFIDENCE IN THE
DETAILS IS VERY LOW CONSIDERING THE SUBSTANTIAL CHANGES IN THE
SYNOPTIC EVOLUTION AND TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED
DURING THIS PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH
MODELS SUGGEST THERE MAY BE SOME DRYING THEREAFTER...POPS WERE
TRENDED CLOSER TO CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE
FORECAST. /NEUMAN

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED TO PREVAIL TODAY AND
TONIGHT. SCATTERED SHOWERS...MOST ACTIVE NORTH OF KSLE...MAY
BRING LOCALIZED AND SHORT TERM MVFR FLIGHT CONDITIONS. THERE WILL
BE A SLIGHT CHANCE OF THUNDERSTORM IN THE KAST AREA AFTER 06Z SAT.

KPDX AND APPROACHES...VFR WILL PREVAIL IN POST FRONTAL SHOWERS
THROUGH FRIDAY. BRIEF MVFR CIGS POSSIBLE WITH HEAVIER SHOWERS. /26

&&

.MARINE...WESTERLY WINDS GUSTING INTO THE LOW 20S OVER THE
NORTHERN WATERS WEST OF 10 NM AND SHOULD CONTINUE TO THROUGH
MIDDAY. THERE ARE SOME GUSTS IN THE 20 TO 25 KT RANGE IN THE
NORTHERN WATERS EAST OF 10 NM BUT ONLY CAPE DISAPPOINTMENT HAS
BEEN CONSISTENT IN REPORTING GUST AROUND 25 KT SO WILL MENTION IN
FCST BUT NOT PUT OUT AN ADVISORY. WINDS CONTINUE TO EASE TONIGHT
AND SAT. THE NEXT WARM FRONT APPROACHES THE WATERS SAT NIGHT AND
SUN BUT STALLS OVER THE NORTHERN MARINE ZONES BEFORE LIFTING NORTH
EARLY MON. MODELS ARE IN FAIR AGREEMENT WITH THIS HAPPENING. AFTER
MONDAY MODEL DIFFERENCES GROW AND FORECAST CONFIDENCE DECREASES.

SEAS HAVE REACHED 10 FT IN THE NORTHERN MARINE ZONES AND ARE
EXPECTED TO DO IN THE SOUTHERN MARINE ZONES SHORTLY. SEAS SHOULD
PEAK AROUND 13 FT LATE THIS MORNING THROUGH AFTERNOON THEN SUBSIDE
BELOW 10 FT LATER THIS EVENING. SEAS REMAIN BELOW 10 FEET THROUGH
EARLY NEXT WEEK. WILL CONTINUE WITH ROUGH BAR CONDITIONS THROUGH
THIS EVENING. /26

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM PDT THIS MORNING FOR
     WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10
     TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
     11 PM PDT THIS EVENING.

&&

$$

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 241045
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
344 AM PDT FRI APR 24 2015

.SYNOPSIS...APRIL SHOWERS WILL CONTINUE THROUGH SATURDAY ACROSS
SOUTHWEST WASHINGTON AND NORTHWEST OREGON. COOL UPPER LEVEL LOW
PRESSURE AND MOIST ONSHORE FLOW WILL COMBINE TO KEEP THE AIR MASS
UNSTABLE ENOUGH FOR SHOWERS TO PERSIST. THE CORE OF THE UPPER LOW
WILL SWING THROUGH WASHINGTON SATURDAY...POSSIBLY CLIPPING AREAS
SALEM NORTH WITH A COUPLE THUNDERSTORMS AND SMALL HAIL. A WARM FRONT
MAY CLIP SOME OF THE FORECAST AREA WITH LIGHT RAIN SUNDAY...THEN HIGH
PRESSURE WILL BUILD IN FROM THE SOUTH FOR DRIER AND MUCH WARMER
WEATHER MONDAY...POSSIBLY TUESDAY AS WELL. THE NEXT COLD FRONT MAY
BRING MORE SHOWERS BY THE MIDDLE OF NEXT WEEK.

&&

.SHORT TERM...TODAY THROUGH MONDAY...WATER VAPOR IMAGERY INDICATES A
BROAD UPPER LEVEL LOW CENTERED NEAR VANCOUVER ISLAND...WITH A
CIRCULATION THAT EXPANDS ACROSS MUCH OF THE AREA BETWEEN BRITISH
COLUMBIA AND OREGON. THIS IS GUIDING A STEADY STREAM OF ONSHORE FLOW
INTO SW WA/NW OR...WITH NUMEROUS SHOWERS MOVING ACROSS THE AREA AS A
RESULT. THIS WILL CONTINUE TO BE THE CASE THROUGH SATURDAY. THE COOL
AIR MASS WILL KEEP SNOW LEVELS NEAR OR JUST BELOW THE CASCADE
PASSES...WITH A FEW INCHES OF NEW SNOW POSSIBLE FOR THE SKI RESORTS.
STRONG APRIL SUNSHINE SHOULD KEEP THE ROADS MAINLY WET ON THE PASSES
DURING THE DAY...BUT ACCUMULATING SNOW COULD MAKE THE PASSES SLICK
THIS MORNING AND AGAIN TONIGHT/SAT MORNING. WILL CONTINUE THE SPS
WHICH HIGHLIGHTS THIS CONCERN.

ONE LOBE OF VORTICITY IS MOVING ONSHORE ALONG THE WASHINGTON AND
EXTREME NORTHERN OREGON COAST...BRINGING SOME ENHANCEMENT TO THE
SHOWER ACTIVITY. SHOWERS REMAIN SHALLOW...GENERALLY TOPPED NEAR OR
BELOW 10 KFT. THEREFORE FOR THE TIME BEING IT DOES NOT LOOK LIKE
THERE IS ENOUGH INSTABILITY FOR THUNDER OR MUCH IN THE WAY OF SMALL
HAIL...AND MODEL SOUNDINGS INDICATE SHOWERS SHOULD REMAIN CAPPED
BELOW 12-15 KFT THROUGHOUT THE DAY TODAY.

A COUPLE INTERESTING THINGS ABOUT THE NAM BUFR SOUNDINGS FOR
TODAY...THERE IS SOME MODEST LOW-LEVEL DIRECTIONAL SHEAR AND STEEP
LOW-LEVEL LAPSE RATES ARE FCST AS TEMPS WARM INTO THE 50S TODAY.
MEANWHILE LCL/S LOOK LOW...AROUND 2-3 KFT...THIS AFTERNOON. THESE ARE
THE INGREDIENTS THAT OFTEN NEED TO COME TOGETHER TO PRODUCE A COUPLE
COLD CORE FUNNELS ACROSS OUR FORECAST AREA...DESPITE THE FACT IT IS
UNLIKELY FOR CONVECTION TO BE DEEP ENOUGH TO GENERATE THUNDER OR EVEN
MUCH HAIL. THAT SAID...WOULD LIKE TO SEE STRONGER FORCING FOR THE SFC
SOUTHERLY FLOW THIS AFTERNOON BEFORE GETTING MORE CONCERNED ABOUT THE
COLD CORE FUNNEL POSSIBILITY.

MODELS SUGGEST THE CORE OF COLD AIR ALOFT WILL SWING ACROSS
WASHINGTON SATURDAY...WITH AN ASSOCIATED LOBE OF -30 TO -32 DEG C 500
MB TEMPS EXTENDING INTO NW OREGON AS FAR SOUTH AS SALEM. THIS WILL
PROVIDE A BETTER CHANCE FOR THUNDER ALONG THE COAST SAT MORNING...
THEN INLAND DURING THE AFTERNOON AS THE UPPER TROUGH AXIS PUSHES
ONSHORE AND INTO THE CASCADES. ADDED MENTION OF SMALL HAIL TO THE
FCST SAT AS THE DEEPER CONVECTION WILL BE MORE FAVORABLE TO DEVELOP
SMALL HAILSTONES. HOWEVER THE LOW-LEVEL SHEAR PROFILE IS WEAKER
SATURDAY THAN TODAY...SO THE CHANCE FOR COLD CORE FUNNELS MAY
ACTUALLY BE LESS THAN TODAY DESPITE THE GREATER BUOYANCY.

WARMER TEMPS ALOFT WILL BUILD IN QUICKLY LATER SAT AFTERNOON AND
EVENING...CAPPING OFF ANY CONVECTION. MODELS SHOW HIGH PRESSURE
BUILDING IN FROM THE S-SW AT THAT POINT...SO THE COMBINATION OF AN
INCREASINGLY LOWER CAP...SUBSIDENCE...AND FINALLY THE LOSS OF SOLAR
HEATING TOWARD SUNSET WILL BRING A SWIFT END TO SHOWER ACTIVITY SAT
EVENING. SUNDAY WILL BE A TRANSITION DAY...WITH AN RAPIDLY AMPLIFYING
UPPER RIDGE PUSHING A WARM FRONT SOUTH TO NORTH ACROSS THE
DISTRICT...POSSIBLY BRUSHING OUR CWA WITH MORE LIGHT RAIN... MAINLY
ALONG THE NORTH COAST. STRONG WARM ADVECTION ALOFT WILL FOLLOW...
WITH 850 MB TEMPS RISING FROM ABOUT +4 DEG C SUN AFTERNOON TO +14
DEG C MONDAY PER THE 00Z/06Z GFS. THEREFORE EXPECT A QUICK RETURN TO
MUCH DRIER WEATHER SUN NIGHT/MON WITH TEMPS WELL INTO THE 70S AND
POSSIBLY APPROACHING 80 FOR THE INLAND VALLEYS MONDAY AFTERNOON.
COASTAL AREAS WILL LIKELY REMAIN IN THE 60S MONDAY DUE TO A LACK OF
A DRIVER FOR STRONG OFFSHORE FLOW.  WEAGLE

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MONDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK REMARKABLY SIMILAR
AT FIRST GLANCE AND MIGHT LEAD ONE TO A RELATIVELY HIGH DEGREE OF
CONFIDENCE IN THE LATEST EXTENDED FORECAST...RUN TO RUN CONSISTENCY
IN BOTH THE EC AND GFS HAS BEEN POOR TO SAY THE LEAST OVER THE LAST
48 HOURS. WHILE I SUSPECT A STORM SYSTEM WILL BRING AT LEAST SOME
THREAT OF RAIN TO THE AREA TUESDAY OR WEDNESDAY...CONFIDENCE IN THE
DETAILS IS VERY LOW CONSIDERING THE SUBSTANTIAL CHANGES IN THE
SYNOPTIC EVOLUTION AND TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED
DURING THIS PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH
MODELS SUGGEST THERE MAY BE SOME DRYING THEREAFTER...POPS WERE
TRENDED CLOSER TO CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE
FORECAST. /NEUMAN

&&

.AVIATION...VFR CONDITIONS ARE EXPECTED TO PREVAIL TODAY AND
TONIGHT. SCATTERED SHOWERS...MOST ACTIVE NORTH OF KSLE...MAY
BRING LOCALIZED AND SHORT TERM MVFR FLIGHT CONDITIONS. THERE WILL
BE A SLIGHT CHANCE OF THUNDERSTORM IN THE KAST AREA AFTER 06Z SAT.

KPDX AND APPROACHES...VFR WILL PREVAIL IN POST FRONTAL SHOWERS
THROUGH FRIDAY. BRIEF MVFR CIGS POSSIBLE WITH HEAVIER SHOWERS. /26

&&

.MARINE...WESTERLY WINDS GUSTING INTO THE LOW 20S OVER THE
NORTHERN WATERS WEST OF 10 NM AND SHOULD CONTINUE TO THROUGH
MIDDAY. THERE ARE SOME GUSTS IN THE 20 TO 25 KT RANGE IN THE
NORTHERN WATERS EAST OF 10 NM BUT ONLY CAPE DISAPPOINTMENT HAS
BEEN CONSISTENT IN REPORTING GUST AROUND 25 KT SO WILL MENTION IN
FCST BUT NOT PUT OUT AN ADVISORY. WINDS CONTINUE TO EASE TONIGHT
AND SAT. THE NEXT WARM FRONT APPROACHES THE WATERS SAT NIGHT AND
SUN BUT STALLS OVER THE NORTHERN MARINE ZONES BEFORE LIFTING NORTH
EARLY MON. MODELS ARE IN FAIR AGREEMENT WITH THIS HAPPENING. AFTER
MONDAY MODEL DIFFERENCES GROW AND FORECAST CONFIDENCE DECREASES.

SEAS HAVE REACHED 10 FT IN THE NORTHERN MARINE ZONES AND ARE
EXPECTED TO DO IN THE SOUTHERN MARINE ZONES SHORTLY. SEAS SHOULD
PEAK AROUND 13 FT LATE THIS MORNING THROUGH AFTERNOON THEN SUBSIDE
BELOW 10 FT LATER THIS EVENING. SEAS REMAIN BELOW 10 FEET THROUGH
EARLY NEXT WEEK. WILL CONTINUE WITH ROUGH BAR CONDITIONS THROUGH
THIS EVENING. /26

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM PDT THIS MORNING FOR
     WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10
     TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO
     FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL
     11 PM PDT THIS EVENING.

&&

$$

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 240409
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
909 PM PDT THU APR 23 2015

.SYNOPSIS...A COLD FRONT MOVED THROUGH SOUTHWEST WASHINGTON AND
NORTHWEST OREGON THIS AFTERNOON AND EVENING. THE COOL PARENT UPPER
LOW WILL REMAIN CENTERED AROUND VANCOUVER ISLAND TONIGHT INTO FRIDAY
NIGHT AS SEVERAL SURGES OF SHOWERS MOVE THROUGH THE FORECAST AREA AT
TIMES. THE SNOW LEVEL WILL LOWER TO BELOW CASCADE PASS ELEVATION
LATER TONIGHT AND WILL CONTINUE TO REMAIN BELOW THE PASSES INTO THE
WEEKEND. THE UPPER TROUGH AXIS WILL MOVE THROUGH ON SATURDAY WITH
POSSIBLY SOME INSTABILITY OVER THE AREA. SOME BRIEF UPPER RIDGING
WILL MOVE IN SATURDAY NIGHT...BUT THEN A WARM FRONT IS EXPECTED TO
BRUSH THE AREA SUNDAY INTO SUNDAY NIGHT BEFORE LIFTING NORTH OF THE
AREA WITH WARMING ON MONDAY. THE NEXT COLD FRONT IS EXPECTED AT SOME
POINT TUESDAY OR WEDNESDAY OF NEXT WEEK.
&&

.SHORT TERM...TONIGHT THROUGH SUNDAY...THE COLD FRONT WITH THE
CURRENT WEATHER SYSTEM MOVED THROUGH SOUTHWEST WASHINGTON AND
NORTHWEST OREGON THIS AFTERNOON AND EVENING...AND IS MOSTLY EAST OF
THE CASCADES THIS EVENING. THE COOL PARENT UPPER LOW IS CENTERED NEAR
VANCOUVER ISLAND AND WILL NOT MOVE MUCH THROUGH FRIDAY INTO FRIDAY
NIGHT. BEHIND THE FRONT THE MODELS INDICATE SNOW LEVELS IN THE
CASCADES WILL LOWER TO AROUND 3000 FEET IN THE SOUTH WASHINGTON
CASCADES AND AROUND MOUNT HOOD LATER TONIGHT AND HOVER AROUND 3000
FEET THROUGH FRIDAY INTO SATURDAY...AND BE CLOSER TO 4000 FEET IN THE
LANE COUNTY CASCADES. HAVE ISSUED A SPECIAL WEATHER STATEMENT ABOUT
THE CASCADE SNOW.

THE MODELS INDICATE THAT THERE IS A SHORT WAVE SWINGING AROUND THE
SOUTHERN PART OF THE LOW INTO WESTERN WASHINGTON LATER TONIGHT AND
FRIDAY MORNING...BRUSHING OUR NORTHERN FORECAST ZONES. THERE IS SOME
850 MB WIND SUPPORT WITH THIS FEATURE...AND WE SHOULD SEE SOME SNOW
ACCUMULATE IN THE CASCADES...WITH THE MOST AT SKI RESORT LEVEL BUT A
COUPLE OF INCHES ARE POSSIBLE AT PASS LEVEL AS WELL.

THE UPPER LOW STARTS TO MOVE INLAND NEAR THE CANADIAN BORDER LATER
FRIDAY NIGHT AND SATURDAY...WITH ONE LAST SHORT WAVE AND THE UPPER
TROUGH AXIS MOVING THROUGH SATURDAY. LOOK FOR MORE SHOWERS
SATURDAY...AND POSSIBLY A FEW THUNDERSTORMS AS WELL. SNOW LEVELS WILL
REMAIN BELOW THE PASSES.

AN UPPER RIDGE WILL MOVE IN SATURDAY NIGHT FOR DRYING THOUGH THIS
COULD LEAD TO AREAS OF FOG OR LOW CLOUDS LATER SATURDAY NIGHT AND
SUNDAY MORNING. THEN THE WARM FRONT WITH THE NEXT SYSTEM IS EXPECTED
TO BRUSH A GOOD CHUNK OF OUR FORECAST AREA WITH SOME LIGHT RAIN
SUNDAY BUT WITH RISING SNOW LEVELS IN THE CASCADES. TOLLESON

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
SUNDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK REMARKABLY SIMILAR
AT FIRST GLANCE AND MIGHT LEAD ONE TO A RELATIVELY HIGH DEGREE OF
CONFIDENCE IN THE LATEST EXTENDED FORECAST...RUN TO RUN CONSISTENCY
IN BOTH THE EC AND GFS HAS BEEN POOR TO SAY THE LEAST OVER THE LAST
48 HOURS. WHILE I SUSPECT A STORM SYSTEM WILL BRING AT LEAST SOME
THREAT OF RAIN TO THE AREA TUESDAY OR WEDNESDAY...CONFIDENCE IN THE
DETAILS IS VERY LOW CONSIDERING THE SUBSTANTIAL CHANGES IN THE
SYNOPTIC EVOLUTION AND TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED
DURING THIS PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH
MODELS SUGGEST THERE MAY BE SOME DRYING THEREAFTER...POPS WERE
TRENDED CLOSER TO CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE
FORECAST. /NEUMAN
&&

.AVIATION...VFR CONDITIONS PREVAILING THROUGH THE EARLY OVERNIGHT
HOURS BUT BRIEF MVFR CONDITIONS REMAIN POSSIBLE IN HEAVIER SHOWERS.
AFTER ABOUT 09Z AND THROUGH FRIDAY MORNING...SHOWERS WILL CONCENTRATE
MORE ALONG THE COAST AND IN THE NORTHERN INLAND AREAS. ADDITIONAL
SHOWERS ARE EXPECTED TO DEVELOP ACROSS THE AREA FRIDAY DURING THE
DAY...BRINGING THE SAME BRIEF MVFR THREAT.

KPDX AND APPROACHES...VFR WILL PREVAIL IN POST FRONTAL SHOWERS
THROUGH FRIDAY. BRIEF MVFR CIGS POSSIBLE WITH HEAVIER SHOWERS. BOWEN
&&

.MARINE...WESTERLY TO SOUTHWESTERLY WINDS AT BUOY 29 ARE STARTING TO
INCREASE A BIT AGAIN THIS EVENING. WITH LATEST SHORT TERM MODELS
TRENDING HIGHER WITH WINDS OVERNIGHT AND INTO FRIDAY MORNING...HAVE
ISSUED A SMALL CRAFT ADVISORY FOR WINDS FOR THE NORTHERN OFFSHORE
WATERS FOR TONIGHT THROUGH FRIDAY MORNING WITH PEAK GUSTS BETWEEN 25
AND 30 KT DURING THAT PERIOD. WIND THREAT FOR THE NORTHERN NEARSHORE
AREA IS MORE MARGINAL SO HAVE LEFT IT OUT OF THE ADVISORY FOR NOW.
AFTER FRIDAY MORNING...NOT EXPECTING ANY SIGNIFICANT STRONG WIND
THREAT UNTIL SUNDAY AS A WARM FRONT LIFTS OVER THE WATERS SUNDAY
MORNING.

INCREASE IN SEAS CONTINUES TO BE PUSHED BACK...BUT SEAS ARE STILL
EXPECTED TO BUILD TO 10-12 FT TONIGHT INTO FRIDAY...PEAKING AROUND 13
FT FRI LATE MORNING AND AFTERNOON. WILL KEEP SMALL CRAFT ADVISORY FOR
SEAS IN PLACE AS IS...ALTHOUGH INITIAL ONSET OF 10 FT SEAS MAY BE
DELAYED SLIGHTLY. BOWEN
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 11 PM THIS EVENING TO 11 AM
     PDT FRIDAY FOR WATERS FROM CAPE SHOALWATER WA TO CASCADE
     HEAD OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 11 PM THIS EVENING
     TO 8 PM PDT FRIDAY 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 7 AM TO 8 PM PDT
     FRIDAY 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 8 AM TO
     6 PM PDT FRIDAY.

&&

$$

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 240409
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
909 PM PDT THU APR 23 2015

.SYNOPSIS...A COLD FRONT MOVED THROUGH SOUTHWEST WASHINGTON AND
NORTHWEST OREGON THIS AFTERNOON AND EVENING. THE COOL PARENT UPPER
LOW WILL REMAIN CENTERED AROUND VANCOUVER ISLAND TONIGHT INTO FRIDAY
NIGHT AS SEVERAL SURGES OF SHOWERS MOVE THROUGH THE FORECAST AREA AT
TIMES. THE SNOW LEVEL WILL LOWER TO BELOW CASCADE PASS ELEVATION
LATER TONIGHT AND WILL CONTINUE TO REMAIN BELOW THE PASSES INTO THE
WEEKEND. THE UPPER TROUGH AXIS WILL MOVE THROUGH ON SATURDAY WITH
POSSIBLY SOME INSTABILITY OVER THE AREA. SOME BRIEF UPPER RIDGING
WILL MOVE IN SATURDAY NIGHT...BUT THEN A WARM FRONT IS EXPECTED TO
BRUSH THE AREA SUNDAY INTO SUNDAY NIGHT BEFORE LIFTING NORTH OF THE
AREA WITH WARMING ON MONDAY. THE NEXT COLD FRONT IS EXPECTED AT SOME
POINT TUESDAY OR WEDNESDAY OF NEXT WEEK.
&&

.SHORT TERM...TONIGHT THROUGH SUNDAY...THE COLD FRONT WITH THE
CURRENT WEATHER SYSTEM MOVED THROUGH SOUTHWEST WASHINGTON AND
NORTHWEST OREGON THIS AFTERNOON AND EVENING...AND IS MOSTLY EAST OF
THE CASCADES THIS EVENING. THE COOL PARENT UPPER LOW IS CENTERED NEAR
VANCOUVER ISLAND AND WILL NOT MOVE MUCH THROUGH FRIDAY INTO FRIDAY
NIGHT. BEHIND THE FRONT THE MODELS INDICATE SNOW LEVELS IN THE
CASCADES WILL LOWER TO AROUND 3000 FEET IN THE SOUTH WASHINGTON
CASCADES AND AROUND MOUNT HOOD LATER TONIGHT AND HOVER AROUND 3000
FEET THROUGH FRIDAY INTO SATURDAY...AND BE CLOSER TO 4000 FEET IN THE
LANE COUNTY CASCADES. HAVE ISSUED A SPECIAL WEATHER STATEMENT ABOUT
THE CASCADE SNOW.

THE MODELS INDICATE THAT THERE IS A SHORT WAVE SWINGING AROUND THE
SOUTHERN PART OF THE LOW INTO WESTERN WASHINGTON LATER TONIGHT AND
FRIDAY MORNING...BRUSHING OUR NORTHERN FORECAST ZONES. THERE IS SOME
850 MB WIND SUPPORT WITH THIS FEATURE...AND WE SHOULD SEE SOME SNOW
ACCUMULATE IN THE CASCADES...WITH THE MOST AT SKI RESORT LEVEL BUT A
COUPLE OF INCHES ARE POSSIBLE AT PASS LEVEL AS WELL.

THE UPPER LOW STARTS TO MOVE INLAND NEAR THE CANADIAN BORDER LATER
FRIDAY NIGHT AND SATURDAY...WITH ONE LAST SHORT WAVE AND THE UPPER
TROUGH AXIS MOVING THROUGH SATURDAY. LOOK FOR MORE SHOWERS
SATURDAY...AND POSSIBLY A FEW THUNDERSTORMS AS WELL. SNOW LEVELS WILL
REMAIN BELOW THE PASSES.

AN UPPER RIDGE WILL MOVE IN SATURDAY NIGHT FOR DRYING THOUGH THIS
COULD LEAD TO AREAS OF FOG OR LOW CLOUDS LATER SATURDAY NIGHT AND
SUNDAY MORNING. THEN THE WARM FRONT WITH THE NEXT SYSTEM IS EXPECTED
TO BRUSH A GOOD CHUNK OF OUR FORECAST AREA WITH SOME LIGHT RAIN
SUNDAY BUT WITH RISING SNOW LEVELS IN THE CASCADES. TOLLESON

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
SUNDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK REMARKABLY SIMILAR
AT FIRST GLANCE AND MIGHT LEAD ONE TO A RELATIVELY HIGH DEGREE OF
CONFIDENCE IN THE LATEST EXTENDED FORECAST...RUN TO RUN CONSISTENCY
IN BOTH THE EC AND GFS HAS BEEN POOR TO SAY THE LEAST OVER THE LAST
48 HOURS. WHILE I SUSPECT A STORM SYSTEM WILL BRING AT LEAST SOME
THREAT OF RAIN TO THE AREA TUESDAY OR WEDNESDAY...CONFIDENCE IN THE
DETAILS IS VERY LOW CONSIDERING THE SUBSTANTIAL CHANGES IN THE
SYNOPTIC EVOLUTION AND TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED
DURING THIS PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH
MODELS SUGGEST THERE MAY BE SOME DRYING THEREAFTER...POPS WERE
TRENDED CLOSER TO CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE
FORECAST. /NEUMAN
&&

.AVIATION...VFR CONDITIONS PREVAILING THROUGH THE EARLY OVERNIGHT
HOURS BUT BRIEF MVFR CONDITIONS REMAIN POSSIBLE IN HEAVIER SHOWERS.
AFTER ABOUT 09Z AND THROUGH FRIDAY MORNING...SHOWERS WILL CONCENTRATE
MORE ALONG THE COAST AND IN THE NORTHERN INLAND AREAS. ADDITIONAL
SHOWERS ARE EXPECTED TO DEVELOP ACROSS THE AREA FRIDAY DURING THE
DAY...BRINGING THE SAME BRIEF MVFR THREAT.

KPDX AND APPROACHES...VFR WILL PREVAIL IN POST FRONTAL SHOWERS
THROUGH FRIDAY. BRIEF MVFR CIGS POSSIBLE WITH HEAVIER SHOWERS. BOWEN
&&

.MARINE...WESTERLY TO SOUTHWESTERLY WINDS AT BUOY 29 ARE STARTING TO
INCREASE A BIT AGAIN THIS EVENING. WITH LATEST SHORT TERM MODELS
TRENDING HIGHER WITH WINDS OVERNIGHT AND INTO FRIDAY MORNING...HAVE
ISSUED A SMALL CRAFT ADVISORY FOR WINDS FOR THE NORTHERN OFFSHORE
WATERS FOR TONIGHT THROUGH FRIDAY MORNING WITH PEAK GUSTS BETWEEN 25
AND 30 KT DURING THAT PERIOD. WIND THREAT FOR THE NORTHERN NEARSHORE
AREA IS MORE MARGINAL SO HAVE LEFT IT OUT OF THE ADVISORY FOR NOW.
AFTER FRIDAY MORNING...NOT EXPECTING ANY SIGNIFICANT STRONG WIND
THREAT UNTIL SUNDAY AS A WARM FRONT LIFTS OVER THE WATERS SUNDAY
MORNING.

INCREASE IN SEAS CONTINUES TO BE PUSHED BACK...BUT SEAS ARE STILL
EXPECTED TO BUILD TO 10-12 FT TONIGHT INTO FRIDAY...PEAKING AROUND 13
FT FRI LATE MORNING AND AFTERNOON. WILL KEEP SMALL CRAFT ADVISORY FOR
SEAS IN PLACE AS IS...ALTHOUGH INITIAL ONSET OF 10 FT SEAS MAY BE
DELAYED SLIGHTLY. BOWEN
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 11 PM THIS EVENING TO 11 AM
     PDT FRIDAY FOR WATERS FROM CAPE SHOALWATER WA TO CASCADE
     HEAD OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 11 PM THIS EVENING
     TO 8 PM PDT FRIDAY 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 7 AM TO 8 PM PDT
     FRIDAY 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 8 AM TO
     6 PM PDT FRIDAY.

&&

$$

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 232214
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
250 PM PDT THU APR 23 2015

.SYNOPSIS...AFTER A FRONT BRINGS WIDESPREAD RAIN TO THE AREA
TODAY...EXPECT A COOL AND SHOWERY AIRMASS TO LINGER ACROSS THE AREA
ON FRIDAY AND SATURDAY. LIGHT SNOW ACCUMULATIONS COULD CREATE
HAZARDOUS TRAVEL OVER THE CASCADE PASSES DURING THIS TIME. A PASSING
WARM FRONT MAY BRING ADDITIONAL LIGHT RAIN TO THE AREA ON
SUNDAY...BUT IT LOOKS INCREASINGLY LIKELY TO REMAIN DRY ACROSS THE
AREA. HIGH PRESSURE SHOULD BRING DRIER AND WARMER WEATHER EARLY NEXT
WEEK...WITH MORE WET WEATHER POSSIBLE LATE TUESDAY OR WEDNESDAY.

&&

.SHORT TERM...TONIGHT THROUGH SUNDAY...INFRARED SATELLITE IMAGERY
SHOWS A FRONTAL SYSTEM PUSHING INTO THE PACIFIC NORTHWEST WITH
PLENTY OF SHOWERS UPSTREAM OVER THE NORTHEAST PACIFIC. SHOWERS
ASSOCIATED WITH A COLD FRONT ARE PUSHING INTO THE REGION THIS
AFTERNOON. RAINFALL AMOUNTS HAVE GENERALLY BEEN UNDER TWO TENTHS OF
AN INCH SO FAR...AND WILL CONTINUE TO REMAIN RELATIVELY LIGHT.
SUBSIDENCE BEHIND THIS FRONT MAY LEAD TO A BRIEF BREAK IN SHOWER
ACTIVITY THIS EVENING...PARTICULARLY IN THE WILLAMETTE VALLEY.
HOWEVER...INSTABILITY WILL DEEPEN OVERNIGHT AND THE SHOWERS APPARENT
ON SATELLITE IMAGERY OVER THE NORTHEAST PACIFIC SHOULD HAVE LITTLE
TROUBLE PUSHING INTO THE WILLAMETTE AND LOWER COLUMBIA RIVER
VALLEYS...ESPECIALLY NORTH OF SALEM.

SNOW LEVELS ARE CURRENTLY HOVERING IN THE 4500 TO 5000 FT RANGE AND
WILL LOWER INTO THE 3000 TO 4000 FT RANGE TONIGHT AND LINGER IN THIS
RANGE THROUGH SATURDAY. WHILE NO MAJOR ACCUMULATIONS ARE EXPECTED
THROUGH FRIDAY...ENOUGH SNOW TO COVER THE ROADS AND CREATE SOME
HAZARDOUS TRAVEL APPEAR PROBABLE...ESPECIALLY LATE TONIGHT AND
FRIDAY MORNING.

MEANWHILE...THE UPPER LEVEL TROUGH RESPONSIBLE FOR SENDING THE
AFOREMENTIONED FRONT ACROSS THE AREA TODAY WILL HOVER OVER SOUTHERN
BRITISH COLUMBIA AND NORTHERN WASHINGTON THROUGH EARLY SATURDAY. BOTH
THE GFS AND EC AGREE A SHORTWAVE TROUGH WILL ROTATE AROUND THIS
UPPER LEVEL TROUGH AND ENHANCE SHOWER ACTIVITY ACROSS THE AREA
FRIDAY NIGHT. WHILE 6 INCHES OF SNOW IN 12 HOURS MAY NOT BE REACHED
AT THE CASCADE PASSES DURING THIS PERIOD...THIS TIME PERIOD MAY SEE
THE HIGHEST SNOWFALL RATES...AND THUS TRAVEL IMPACTS IN THE CASCADES
OVER THE NEXT SEVERAL DAYS.

AS THE COLD POOL ALOFT SKIRTS OUR NORTHERN ZONES LATE FRIDAY NIGHT
AND EARLY SATURDAY...A COUPLE OF THUNDERSTORMS WILL BE POSSIBLE.
MODELS HAVE WAVERED A BIT ON THE AMOUNT OF INSTABILITY...BUT THINK
THE CURRENT AREAL EXTENT OF THUNDER STILL SEEMS PLAUSIBLE GIVEN THE
PATTERN. SHORTWAVE RIDGING BUILDING INTO THE REGION LATE SATURDAY
SHOULD BRING A RAPID DECREASE IN SHOWER ACTIVITY SATURDAY EVENING
ACROSS THE REGION. UNDER CLEARING SKIES...EXPECT A RELATIVELY COOL
NIGHT ACROSS THE AREA SATURDAY NIGHT...NOT ALL THAT DISSIMILAR TO
LAST NIGHTS LOW TEMPERATURES.

BOTH THE GFS AND EC CONTINUE TO ADVERTISE A WARM FRONT SPREADING RAIN
INTO OUR NORTHWESTERN ZONES SUNDAY AND SUNDAY NIGHT. WHILE THE
OPERATIONAL MODELS HAD BEEN TRENDING DRIER OVER THE PAST COUPLE OF
DAYS...THE LATEST OPERATIONAL RUNS SEEM TO BE MORE IN THE MIDDLE OF
THEIR RESPECTIVE ENSEMBLE MEMBERS AND PRODUCE SOME LIGHT RAIN ACROSS
MAINLY THE NORTHWESTERN HALF OF THE CWA SUNDAY INTO SUNDAY NIGHT. AS
A RESULT...FEW CHANGES WERE MADE TO THIS PORTION OF THE FORECAST AS
THE INHERITED FORECAST SEEMED TO CAPTURE THIS TREND AND THE
UNCERTAINTY WELL. /NEUMAN


.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK
REMARKABLY SIMILAR AT FIRST GLANCE AND MIGHT LEAD ONE TO A
RELATIVELY HIGH DEGREE OF CONFIDENCE IN THE LATEST EXTENDED
FORECAST...RUN TO RUN CONSISTENCY IN BOTH THE EC AND GFS HAS BEEN
POOR TO SAY THE LEAST OVER THE LAST 48 HOURS. WHILE I SUSPECT A
STORM SYSTEM WILL BRING AT LEAST SOME THREAT OF RAIN TO THE AREA
TUESDAY OR WEDNESDAY...CONFIDENCE IN THE DETAILS IS VERY LOW
CONSIDERING THE SUBSTANTIAL CHANGES IN THE SYNOPTIC EVOLUTION AND
TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED DURING THIS
PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH MODELS SUGGEST
THERE MAY BE SOME DRYING THEREAFTER...POPS WERE TRENDED CLOSER TO
CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE FORECAST. /NEUMAN


&&

.AVIATION...A COLD FRONT WILL MOVE ONSHORE THROUGH THIS AFTERNOON
AND EVENING...LOWERING CIGS ALONG THE COAST TO MVFR AROUND 1500-2500
FT...WITH IFR CONDITIONS POSSIBLE IN HEAVIER RAIN. INLAND SITES
WILL STAY MOSTLY VFR EXCEPT FOR MVFR CIGS AROUND 2500-3000 FT
THROUGH 02Z FRI. SHOWERS WILL QUICKLY FILL IN BEHIND THE FRONTAL
PASSAGE TONIGHT...ALLOWING CONDITIONS TO IMPROVE TO MOSTLY VFR
TONIGHT. ANOTHER ROUND OF MVFR CONDITIONS IS EXPECTED AFTER 14Z
FRI IN HEAVIER SHOWERS...MAINLY ALONG THE COAST AND INLAND NORTH.

KPDX AND APPROACHES...EXPECT MVFR CIGS AROUND 2500-3500 FT THROUGH
00Z-01Z FRI AS THE FRONT PUSHES INLAND THIS AFTERNOON. VFR
CONDITIONS QUICKLY RETURN AND WILL PREVAIL IN POST FRONTAL
SHOWERS THROUGH TONIGHT. BUT THERE MAY BE LINGERING MVFR
CONDITIONS TOWARD THE MOUNTAINS. MVFR CIGS POSSIBLE AGAIN BETWEEN
10-14Z FRI. /27

&&

.MARINE...COLD FRONT CURRENTLY MAKING ITS WAY THROUGH THE COASTAL
WATERS. AFTER BRIEF GALE FORCE WINDS WITH GUSTS TO 35 KTS OVER THE
NORTHERN INNER COASTAL WATERS...WESTERLY WINDS HAVE QUICKLY
REPLACED THE SOUTHERLY OVER THE NORTHERN WATERS THIS AFTERNOON.
SOUTH WINDS STILL GUSTING IN SMALL CRAFT ADVISORY CRITERIA...WITH
STRONGEST GUSTS OVER THE SOUTHERN INNER WATERS. WINDS QUICKLY
QUIET DOWN BY EARLY THIS EVENING ONCE THE FRONT PUSHES INLAND...
STAYING BELOW CRITERIA THROUGH AT LEAST SATURDAY. WE COULD SEE
OCCASIONAL GUSTS NEAR 21 KTS FRIDAY MORNING BUT ITS LOOKING
MARGINAL AT BEST. NOT EXPECTING ANY SIGNIFICANT STRONG WIND
THREAT UNTIL SUNDAY AS A WARM FRONT LIFTS OVER THE WATERS SUNDAY
MORNING.

SEAS WILL PICK TO 10-12 FT TONIGHT INTO FRIDAY...PEAKING AROUND
13 FT LATE TONIGHT AND FRI. BUOY 05 IS NOW AROUND 12 FT THIS
AFTERNOON...WHICH CORRESPONDS WELL WITH MODELS. MODELS HAVE
PUSHED BACK ON THE TIMING OF THE INCOMING HIGHER SEAS UNTIL CLOSER
TO 06Z FRI FOR THE OUTER WATERS AND CLOSER TO 12Z FRI FOR THE
INNER WATERS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 11 PM THIS
     EVENING TO 8 PM PDT FRIDAY FOR WATERS FROM CAPE SHOALWATER
     TO FLORENCE FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 7 AM TO 8 PM
     PDT FRIDAY FOR COASTAL WATERS FROM CAPE SHOALWATER TO
     FLORENCE OUT 10 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 PM PDT THIS AFTERNOON
     FOR COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 8 PM
     TO 11 PM PDT THIS EVENING...AND FROM 8 AM TO 6 PM PDT FRIDAY

&&


$$

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 232214
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
250 PM PDT THU APR 23 2015

.SYNOPSIS...AFTER A FRONT BRINGS WIDESPREAD RAIN TO THE AREA
TODAY...EXPECT A COOL AND SHOWERY AIRMASS TO LINGER ACROSS THE AREA
ON FRIDAY AND SATURDAY. LIGHT SNOW ACCUMULATIONS COULD CREATE
HAZARDOUS TRAVEL OVER THE CASCADE PASSES DURING THIS TIME. A PASSING
WARM FRONT MAY BRING ADDITIONAL LIGHT RAIN TO THE AREA ON
SUNDAY...BUT IT LOOKS INCREASINGLY LIKELY TO REMAIN DRY ACROSS THE
AREA. HIGH PRESSURE SHOULD BRING DRIER AND WARMER WEATHER EARLY NEXT
WEEK...WITH MORE WET WEATHER POSSIBLE LATE TUESDAY OR WEDNESDAY.

&&

.SHORT TERM...TONIGHT THROUGH SUNDAY...INFRARED SATELLITE IMAGERY
SHOWS A FRONTAL SYSTEM PUSHING INTO THE PACIFIC NORTHWEST WITH
PLENTY OF SHOWERS UPSTREAM OVER THE NORTHEAST PACIFIC. SHOWERS
ASSOCIATED WITH A COLD FRONT ARE PUSHING INTO THE REGION THIS
AFTERNOON. RAINFALL AMOUNTS HAVE GENERALLY BEEN UNDER TWO TENTHS OF
AN INCH SO FAR...AND WILL CONTINUE TO REMAIN RELATIVELY LIGHT.
SUBSIDENCE BEHIND THIS FRONT MAY LEAD TO A BRIEF BREAK IN SHOWER
ACTIVITY THIS EVENING...PARTICULARLY IN THE WILLAMETTE VALLEY.
HOWEVER...INSTABILITY WILL DEEPEN OVERNIGHT AND THE SHOWERS APPARENT
ON SATELLITE IMAGERY OVER THE NORTHEAST PACIFIC SHOULD HAVE LITTLE
TROUBLE PUSHING INTO THE WILLAMETTE AND LOWER COLUMBIA RIVER
VALLEYS...ESPECIALLY NORTH OF SALEM.

SNOW LEVELS ARE CURRENTLY HOVERING IN THE 4500 TO 5000 FT RANGE AND
WILL LOWER INTO THE 3000 TO 4000 FT RANGE TONIGHT AND LINGER IN THIS
RANGE THROUGH SATURDAY. WHILE NO MAJOR ACCUMULATIONS ARE EXPECTED
THROUGH FRIDAY...ENOUGH SNOW TO COVER THE ROADS AND CREATE SOME
HAZARDOUS TRAVEL APPEAR PROBABLE...ESPECIALLY LATE TONIGHT AND
FRIDAY MORNING.

MEANWHILE...THE UPPER LEVEL TROUGH RESPONSIBLE FOR SENDING THE
AFOREMENTIONED FRONT ACROSS THE AREA TODAY WILL HOVER OVER SOUTHERN
BRITISH COLUMBIA AND NORTHERN WASHINGTON THROUGH EARLY SATURDAY. BOTH
THE GFS AND EC AGREE A SHORTWAVE TROUGH WILL ROTATE AROUND THIS
UPPER LEVEL TROUGH AND ENHANCE SHOWER ACTIVITY ACROSS THE AREA
FRIDAY NIGHT. WHILE 6 INCHES OF SNOW IN 12 HOURS MAY NOT BE REACHED
AT THE CASCADE PASSES DURING THIS PERIOD...THIS TIME PERIOD MAY SEE
THE HIGHEST SNOWFALL RATES...AND THUS TRAVEL IMPACTS IN THE CASCADES
OVER THE NEXT SEVERAL DAYS.

AS THE COLD POOL ALOFT SKIRTS OUR NORTHERN ZONES LATE FRIDAY NIGHT
AND EARLY SATURDAY...A COUPLE OF THUNDERSTORMS WILL BE POSSIBLE.
MODELS HAVE WAVERED A BIT ON THE AMOUNT OF INSTABILITY...BUT THINK
THE CURRENT AREAL EXTENT OF THUNDER STILL SEEMS PLAUSIBLE GIVEN THE
PATTERN. SHORTWAVE RIDGING BUILDING INTO THE REGION LATE SATURDAY
SHOULD BRING A RAPID DECREASE IN SHOWER ACTIVITY SATURDAY EVENING
ACROSS THE REGION. UNDER CLEARING SKIES...EXPECT A RELATIVELY COOL
NIGHT ACROSS THE AREA SATURDAY NIGHT...NOT ALL THAT DISSIMILAR TO
LAST NIGHTS LOW TEMPERATURES.

BOTH THE GFS AND EC CONTINUE TO ADVERTISE A WARM FRONT SPREADING RAIN
INTO OUR NORTHWESTERN ZONES SUNDAY AND SUNDAY NIGHT. WHILE THE
OPERATIONAL MODELS HAD BEEN TRENDING DRIER OVER THE PAST COUPLE OF
DAYS...THE LATEST OPERATIONAL RUNS SEEM TO BE MORE IN THE MIDDLE OF
THEIR RESPECTIVE ENSEMBLE MEMBERS AND PRODUCE SOME LIGHT RAIN ACROSS
MAINLY THE NORTHWESTERN HALF OF THE CWA SUNDAY INTO SUNDAY NIGHT. AS
A RESULT...FEW CHANGES WERE MADE TO THIS PORTION OF THE FORECAST AS
THE INHERITED FORECAST SEEMED TO CAPTURE THIS TREND AND THE
UNCERTAINTY WELL. /NEUMAN


.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK
REMARKABLY SIMILAR AT FIRST GLANCE AND MIGHT LEAD ONE TO A
RELATIVELY HIGH DEGREE OF CONFIDENCE IN THE LATEST EXTENDED
FORECAST...RUN TO RUN CONSISTENCY IN BOTH THE EC AND GFS HAS BEEN
POOR TO SAY THE LEAST OVER THE LAST 48 HOURS. WHILE I SUSPECT A
STORM SYSTEM WILL BRING AT LEAST SOME THREAT OF RAIN TO THE AREA
TUESDAY OR WEDNESDAY...CONFIDENCE IN THE DETAILS IS VERY LOW
CONSIDERING THE SUBSTANTIAL CHANGES IN THE SYNOPTIC EVOLUTION AND
TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED DURING THIS
PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH MODELS SUGGEST
THERE MAY BE SOME DRYING THEREAFTER...POPS WERE TRENDED CLOSER TO
CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE FORECAST. /NEUMAN


&&

.AVIATION...A COLD FRONT WILL MOVE ONSHORE THROUGH THIS AFTERNOON
AND EVENING...LOWERING CIGS ALONG THE COAST TO MVFR AROUND 1500-2500
FT...WITH IFR CONDITIONS POSSIBLE IN HEAVIER RAIN. INLAND SITES
WILL STAY MOSTLY VFR EXCEPT FOR MVFR CIGS AROUND 2500-3000 FT
THROUGH 02Z FRI. SHOWERS WILL QUICKLY FILL IN BEHIND THE FRONTAL
PASSAGE TONIGHT...ALLOWING CONDITIONS TO IMPROVE TO MOSTLY VFR
TONIGHT. ANOTHER ROUND OF MVFR CONDITIONS IS EXPECTED AFTER 14Z
FRI IN HEAVIER SHOWERS...MAINLY ALONG THE COAST AND INLAND NORTH.

KPDX AND APPROACHES...EXPECT MVFR CIGS AROUND 2500-3500 FT THROUGH
00Z-01Z FRI AS THE FRONT PUSHES INLAND THIS AFTERNOON. VFR
CONDITIONS QUICKLY RETURN AND WILL PREVAIL IN POST FRONTAL
SHOWERS THROUGH TONIGHT. BUT THERE MAY BE LINGERING MVFR
CONDITIONS TOWARD THE MOUNTAINS. MVFR CIGS POSSIBLE AGAIN BETWEEN
10-14Z FRI. /27

&&

.MARINE...COLD FRONT CURRENTLY MAKING ITS WAY THROUGH THE COASTAL
WATERS. AFTER BRIEF GALE FORCE WINDS WITH GUSTS TO 35 KTS OVER THE
NORTHERN INNER COASTAL WATERS...WESTERLY WINDS HAVE QUICKLY
REPLACED THE SOUTHERLY OVER THE NORTHERN WATERS THIS AFTERNOON.
SOUTH WINDS STILL GUSTING IN SMALL CRAFT ADVISORY CRITERIA...WITH
STRONGEST GUSTS OVER THE SOUTHERN INNER WATERS. WINDS QUICKLY
QUIET DOWN BY EARLY THIS EVENING ONCE THE FRONT PUSHES INLAND...
STAYING BELOW CRITERIA THROUGH AT LEAST SATURDAY. WE COULD SEE
OCCASIONAL GUSTS NEAR 21 KTS FRIDAY MORNING BUT ITS LOOKING
MARGINAL AT BEST. NOT EXPECTING ANY SIGNIFICANT STRONG WIND
THREAT UNTIL SUNDAY AS A WARM FRONT LIFTS OVER THE WATERS SUNDAY
MORNING.

SEAS WILL PICK TO 10-12 FT TONIGHT INTO FRIDAY...PEAKING AROUND
13 FT LATE TONIGHT AND FRI. BUOY 05 IS NOW AROUND 12 FT THIS
AFTERNOON...WHICH CORRESPONDS WELL WITH MODELS. MODELS HAVE
PUSHED BACK ON THE TIMING OF THE INCOMING HIGHER SEAS UNTIL CLOSER
TO 06Z FRI FOR THE OUTER WATERS AND CLOSER TO 12Z FRI FOR THE
INNER WATERS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 11 PM THIS
     EVENING TO 8 PM PDT FRIDAY FOR WATERS FROM CAPE SHOALWATER
     TO FLORENCE FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 7 AM TO 8 PM
     PDT FRIDAY FOR COASTAL WATERS FROM CAPE SHOALWATER TO
     FLORENCE OUT 10 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 PM PDT THIS AFTERNOON
     FOR COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 8 PM
     TO 11 PM PDT THIS EVENING...AND FROM 8 AM TO 6 PM PDT FRIDAY

&&


$$

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 232214
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
250 PM PDT THU APR 23 2015

.SYNOPSIS...AFTER A FRONT BRINGS WIDESPREAD RAIN TO THE AREA
TODAY...EXPECT A COOL AND SHOWERY AIRMASS TO LINGER ACROSS THE AREA
ON FRIDAY AND SATURDAY. LIGHT SNOW ACCUMULATIONS COULD CREATE
HAZARDOUS TRAVEL OVER THE CASCADE PASSES DURING THIS TIME. A PASSING
WARM FRONT MAY BRING ADDITIONAL LIGHT RAIN TO THE AREA ON
SUNDAY...BUT IT LOOKS INCREASINGLY LIKELY TO REMAIN DRY ACROSS THE
AREA. HIGH PRESSURE SHOULD BRING DRIER AND WARMER WEATHER EARLY NEXT
WEEK...WITH MORE WET WEATHER POSSIBLE LATE TUESDAY OR WEDNESDAY.

&&

.SHORT TERM...TONIGHT THROUGH SUNDAY...INFRARED SATELLITE IMAGERY
SHOWS A FRONTAL SYSTEM PUSHING INTO THE PACIFIC NORTHWEST WITH
PLENTY OF SHOWERS UPSTREAM OVER THE NORTHEAST PACIFIC. SHOWERS
ASSOCIATED WITH A COLD FRONT ARE PUSHING INTO THE REGION THIS
AFTERNOON. RAINFALL AMOUNTS HAVE GENERALLY BEEN UNDER TWO TENTHS OF
AN INCH SO FAR...AND WILL CONTINUE TO REMAIN RELATIVELY LIGHT.
SUBSIDENCE BEHIND THIS FRONT MAY LEAD TO A BRIEF BREAK IN SHOWER
ACTIVITY THIS EVENING...PARTICULARLY IN THE WILLAMETTE VALLEY.
HOWEVER...INSTABILITY WILL DEEPEN OVERNIGHT AND THE SHOWERS APPARENT
ON SATELLITE IMAGERY OVER THE NORTHEAST PACIFIC SHOULD HAVE LITTLE
TROUBLE PUSHING INTO THE WILLAMETTE AND LOWER COLUMBIA RIVER
VALLEYS...ESPECIALLY NORTH OF SALEM.

SNOW LEVELS ARE CURRENTLY HOVERING IN THE 4500 TO 5000 FT RANGE AND
WILL LOWER INTO THE 3000 TO 4000 FT RANGE TONIGHT AND LINGER IN THIS
RANGE THROUGH SATURDAY. WHILE NO MAJOR ACCUMULATIONS ARE EXPECTED
THROUGH FRIDAY...ENOUGH SNOW TO COVER THE ROADS AND CREATE SOME
HAZARDOUS TRAVEL APPEAR PROBABLE...ESPECIALLY LATE TONIGHT AND
FRIDAY MORNING.

MEANWHILE...THE UPPER LEVEL TROUGH RESPONSIBLE FOR SENDING THE
AFOREMENTIONED FRONT ACROSS THE AREA TODAY WILL HOVER OVER SOUTHERN
BRITISH COLUMBIA AND NORTHERN WASHINGTON THROUGH EARLY SATURDAY. BOTH
THE GFS AND EC AGREE A SHORTWAVE TROUGH WILL ROTATE AROUND THIS
UPPER LEVEL TROUGH AND ENHANCE SHOWER ACTIVITY ACROSS THE AREA
FRIDAY NIGHT. WHILE 6 INCHES OF SNOW IN 12 HOURS MAY NOT BE REACHED
AT THE CASCADE PASSES DURING THIS PERIOD...THIS TIME PERIOD MAY SEE
THE HIGHEST SNOWFALL RATES...AND THUS TRAVEL IMPACTS IN THE CASCADES
OVER THE NEXT SEVERAL DAYS.

AS THE COLD POOL ALOFT SKIRTS OUR NORTHERN ZONES LATE FRIDAY NIGHT
AND EARLY SATURDAY...A COUPLE OF THUNDERSTORMS WILL BE POSSIBLE.
MODELS HAVE WAVERED A BIT ON THE AMOUNT OF INSTABILITY...BUT THINK
THE CURRENT AREAL EXTENT OF THUNDER STILL SEEMS PLAUSIBLE GIVEN THE
PATTERN. SHORTWAVE RIDGING BUILDING INTO THE REGION LATE SATURDAY
SHOULD BRING A RAPID DECREASE IN SHOWER ACTIVITY SATURDAY EVENING
ACROSS THE REGION. UNDER CLEARING SKIES...EXPECT A RELATIVELY COOL
NIGHT ACROSS THE AREA SATURDAY NIGHT...NOT ALL THAT DISSIMILAR TO
LAST NIGHTS LOW TEMPERATURES.

BOTH THE GFS AND EC CONTINUE TO ADVERTISE A WARM FRONT SPREADING RAIN
INTO OUR NORTHWESTERN ZONES SUNDAY AND SUNDAY NIGHT. WHILE THE
OPERATIONAL MODELS HAD BEEN TRENDING DRIER OVER THE PAST COUPLE OF
DAYS...THE LATEST OPERATIONAL RUNS SEEM TO BE MORE IN THE MIDDLE OF
THEIR RESPECTIVE ENSEMBLE MEMBERS AND PRODUCE SOME LIGHT RAIN ACROSS
MAINLY THE NORTHWESTERN HALF OF THE CWA SUNDAY INTO SUNDAY NIGHT. AS
A RESULT...FEW CHANGES WERE MADE TO THIS PORTION OF THE FORECAST AS
THE INHERITED FORECAST SEEMED TO CAPTURE THIS TREND AND THE
UNCERTAINTY WELL. /NEUMAN


.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...WHILE MODELS LOOK
REMARKABLY SIMILAR AT FIRST GLANCE AND MIGHT LEAD ONE TO A
RELATIVELY HIGH DEGREE OF CONFIDENCE IN THE LATEST EXTENDED
FORECAST...RUN TO RUN CONSISTENCY IN BOTH THE EC AND GFS HAS BEEN
POOR TO SAY THE LEAST OVER THE LAST 48 HOURS. WHILE I SUSPECT A
STORM SYSTEM WILL BRING AT LEAST SOME THREAT OF RAIN TO THE AREA
TUESDAY OR WEDNESDAY...CONFIDENCE IN THE DETAILS IS VERY LOW
CONSIDERING THE SUBSTANTIAL CHANGES IN THE SYNOPTIC EVOLUTION AND
TIMING. SLIGHT CHANCE TO CHANCE POPS WERE USED DURING THIS
PERIOD...AND PERHAPS ARE A BIT TOO LOW. EVEN THOUGH MODELS SUGGEST
THERE MAY BE SOME DRYING THEREAFTER...POPS WERE TRENDED CLOSER TO
CLIMO DUE TO THE EVEN GREATER UNCERTAINTY IN THE FORECAST. /NEUMAN


&&

.AVIATION...A COLD FRONT WILL MOVE ONSHORE THROUGH THIS AFTERNOON
AND EVENING...LOWERING CIGS ALONG THE COAST TO MVFR AROUND 1500-2500
FT...WITH IFR CONDITIONS POSSIBLE IN HEAVIER RAIN. INLAND SITES
WILL STAY MOSTLY VFR EXCEPT FOR MVFR CIGS AROUND 2500-3000 FT
THROUGH 02Z FRI. SHOWERS WILL QUICKLY FILL IN BEHIND THE FRONTAL
PASSAGE TONIGHT...ALLOWING CONDITIONS TO IMPROVE TO MOSTLY VFR
TONIGHT. ANOTHER ROUND OF MVFR CONDITIONS IS EXPECTED AFTER 14Z
FRI IN HEAVIER SHOWERS...MAINLY ALONG THE COAST AND INLAND NORTH.

KPDX AND APPROACHES...EXPECT MVFR CIGS AROUND 2500-3500 FT THROUGH
00Z-01Z FRI AS THE FRONT PUSHES INLAND THIS AFTERNOON. VFR
CONDITIONS QUICKLY RETURN AND WILL PREVAIL IN POST FRONTAL
SHOWERS THROUGH TONIGHT. BUT THERE MAY BE LINGERING MVFR
CONDITIONS TOWARD THE MOUNTAINS. MVFR CIGS POSSIBLE AGAIN BETWEEN
10-14Z FRI. /27

&&

.MARINE...COLD FRONT CURRENTLY MAKING ITS WAY THROUGH THE COASTAL
WATERS. AFTER BRIEF GALE FORCE WINDS WITH GUSTS TO 35 KTS OVER THE
NORTHERN INNER COASTAL WATERS...WESTERLY WINDS HAVE QUICKLY
REPLACED THE SOUTHERLY OVER THE NORTHERN WATERS THIS AFTERNOON.
SOUTH WINDS STILL GUSTING IN SMALL CRAFT ADVISORY CRITERIA...WITH
STRONGEST GUSTS OVER THE SOUTHERN INNER WATERS. WINDS QUICKLY
QUIET DOWN BY EARLY THIS EVENING ONCE THE FRONT PUSHES INLAND...
STAYING BELOW CRITERIA THROUGH AT LEAST SATURDAY. WE COULD SEE
OCCASIONAL GUSTS NEAR 21 KTS FRIDAY MORNING BUT ITS LOOKING
MARGINAL AT BEST. NOT EXPECTING ANY SIGNIFICANT STRONG WIND
THREAT UNTIL SUNDAY AS A WARM FRONT LIFTS OVER THE WATERS SUNDAY
MORNING.

SEAS WILL PICK TO 10-12 FT TONIGHT INTO FRIDAY...PEAKING AROUND
13 FT LATE TONIGHT AND FRI. BUOY 05 IS NOW AROUND 12 FT THIS
AFTERNOON...WHICH CORRESPONDS WELL WITH MODELS. MODELS HAVE
PUSHED BACK ON THE TIMING OF THE INCOMING HIGHER SEAS UNTIL CLOSER
TO 06Z FRI FOR THE OUTER WATERS AND CLOSER TO 12Z FRI FOR THE
INNER WATERS.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 11 PM THIS
     EVENING TO 8 PM PDT FRIDAY FOR WATERS FROM CAPE SHOALWATER
     TO FLORENCE FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 7 AM TO 8 PM
     PDT FRIDAY FOR COASTAL WATERS FROM CAPE SHOALWATER TO
     FLORENCE OUT 10 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 PM PDT THIS AFTERNOON
     FOR COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 8 PM
     TO 11 PM PDT THIS EVENING...AND FROM 8 AM TO 6 PM PDT FRIDAY

&&


$$

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 231628
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
925 AM PDT THU APR 23 2015

.SYNOPSIS...AFTER A FRONT BRINGS WIDESPREAD RAIN TO THE AREA
TODAY...EXPECT A COOL AND SHOWERY AIRMASS TO LINGER ACROSS THE AREA
ON FRIDAY AND SATURDAY. A PASSING WARM FRONT MAY BRING ADDITIONAL
LIGHT RAIN TO THE AREA ON SUNDAY...BUT IT LOOKS INCREASINGLY LIKELY
TO REMAIN DRY ACROSS THE AREA. HIGH PRESSURE SHOULD BRING DRIER AND
WARMER WEATHER EARLY NEXT WEEK...WITH MORE WET WEATHER LIKELY EITHER
LATE TUESDAY OR WEDNESDAY.

&&

.SHORT TERM...TONIGHT THROUGH SATURDAY...DOPPLER RADAR SHOWS A LARGE
SWATH OF RAIN MOVING EASTWARD INTO NORTHWEST OREGON THIS MORNING.
WHILE THIS HAS PRIMARILY BEEN VIRGA...THE LOWER ATMOSPHERE IS
BEGINNING TO MOISTEN ENOUGH THAT LIGHT RAIN IS STARTING TO REACH THE
SURFACE. ADDITIONAL SHOWERS OFF THE COAST OF OREGON AND WASHINGTON
APPARENT VIA KLGX RADAR ARE ASSOCIATED WITH THE MAIN FRONT THAT IS
CURRENTLY APPROACHING THE REGION. THIS FRONT AND SHOWER ACTIVITY
WILL SPREAD INLAND MIDDAY AND THIS AFTERNOON.

SUBSIDENCE BEHIND THE FRONT SHOULD PRODUCE A BREAK IN THE WET
WEATHER THIS EVENING AWAY FROM THE HIGHER TERRAIN.
HOWEVER...CONTINUING ONSHORE FLOW WILL ALLOW ADDITIONAL SHOWERS TO
SPREAD INTO THE AREA LATER TONIGHT. INSTABILITY WILL INITIALLY BE
SHALLOW ENOUGH THAT THESE SHOWERS WILL LIKELY REMAIN CONFINED TO THE
COAST...COAST RANGE AND CASCADES...BUT DEEPENING INSTABILTY...FROM
NORTH TO SOUTH...SHOULD EVENTUALLY ALLOW SHOWERS TO SPREAD INTO THE
WILLAMETTE AND LOWER COLUMBIA RIVER VALLEYS OVERNIGHT AND INTO
FRIDAY MORNING. DAYTIME HEATING SHOULD FURTHER ENHANCE SHOWER
ACTIVITY INLAND...BUT THUNDERSTORMS APPEAR VERY UNLIKELY.

SNOW LEVELS SHOULD LOWER SOLIDLY BELOW PASS LEVEL OVERNIGHT. WHILE
WINTER WX ADVISORY CRITERIA SNOW ACCUMULATIONS OF MORE THAN 6 INCHES
APPEAR UNLIKELY AT THE PASSES...THERE WILL LIKELY BE A PERIOD OF
HAZARDOUS TRAVEL OVER THE PASSES FRIDAY MORNING AND DURING ANY OF THE
INTENSE SHOWERS FRIDAY AFTERNOON. WILL PLAN ON HIGHLIGHTING THIS ON
SOCIAL MEDIA.

THE UPPER LEVEL TROUGH RESPONSIBLE FOR SENDING THE FRONT ACROSS THE
AREA TODAY...WILL SLOWLY MEANDER ACROSS THE AREA LATE FRIDAY NIGHT
AND SATURDAY BEFORE DIVING INTO THE GREAT BASIN. INSTABILITY WILL
DEEPEN AS A RESULT...AND EXPECT ADDITIONAL SHOWERS TO SPREAD INTO
THE AREA DURING THIS PERIOD. SOME SHOWERS MAY BE DEEP ENOUGH THAT A
FEW THUNDERSTORMS WILL BE POSSIBLE SO MAINTAINED THE SLIGHT CHANCE
OF THUNDER FOR THE MOST SUSCEPTIBLE LOCATIONS.

SHORTWAVE RIDGING SHOULD LEAD TO SHOWERS ENDING FAIRLY QUICKLY
SATURDAY EVENING...WITH ANOTHER COOL NIGHT IN STORE. MODELS CONTINUE
TO TREND DRIER FOR SUNDAY...BUT SOME ENSEMBLE MEMBERS ARE STILL
HANGING ONTO THE IDEA THAT A WARM FRONT WILL BRING RAIN TO THE AREA.
WILL EVALUATE THIS FURTHER WITH THE AFTERNOON FORECAST PACKAGE.
/NEUMAN


.LONG TERM...SUNDAY THROUGH WEDNESDAY...PREVIOUS DISCUSSION
BELOW...MADE VERY FEW CHANGES TO THE EXTENDED FORECAST...AS THE
OVERALL GIST OF THE FORECAST LOOKS TO BE ON TRACK. THE 00Z ECMWF
JOINED THE GFS/GEM IN STRENGTHENING THE UPPER RIDGE ENOUGH TO DRY OUT
THE VAST MAJORITY OF OUR FORECAST AREA SUNDAY THROUGH TUESDAY.
HOWEVER...THERE IS STILL A SIGNIFICANT NUMBER OF ENSEMBLE MEMBERS
WHICH DIFFER FROM THE 00Z OPERATIONAL GFS/ECMWF/GEM SOLUTIONS. THIS
UNCERTAINTY SHOWS IN GFS ENSEMBLE MOS FORECAST OUTPUT...WITH ENSEMBLE
AVERAGE POPS REMAINING IN THE 30S AND 40S AND A LARGE STANDARD
DEVIATION BETWEEN MEMBERS. THEREFORE WE DECIDED NOT TO ELIMINATE THE
MENTION OF RAIN FOR SUNDAY JUST YET. HOWEVER IF MODELS CONTINUE TO
TREND IN THE DIRECTION THEY HAVE BEEN MOVING...SUNDAY COULD BE A MILD
AND DRY DAY ACROSS MUCH OF OUR CWA...WITH A SWING BACK TO ABOVE
NORMAL TEMPS MON AND POSSIBLY TUE. MODEL CONSENSUS SHOWS NEXT FRONT
ARRIVING SOMETIME MIDWEEK...THOUGH TIMING DETAILS VARY BETWEEN
MODELS.  WEAGLE


&&

.AVIATION...MOSTLY VFR CONDITIONS AS A FRONTAL SYSTEM BRINGS LIGHT
RAIN AND OCCASIONAL MVFR CIGS TO THE REGION TODAY. EXPECT A PERIOD
OF WIDESPREAD MVFR CIGS AS THE FRONT MOVES ONSHORE LATE THIS
MORNING INTO THIS AFTERNOON AROUND 20Z THU-02Z FRI. COASTAL AREAS
LIKELY TO HAVE A LONGER PERIOD OF LOWERED FLIGHT CONDITIONS.
CONDITIONS IMPROVING WITH POST FRONTAL SHOWERS TONIGHT. HOWEVER
MOUNTAINS LIKELY BECOMING OBSCURED WITH AND AFTER THE FRONT MOVES
THROUGH.

KPDX AND APPROACHES...VFR WITH A MID CLOUD DECK AROUND 5000 TO
7000 FT WELL AHEAD OF THE FRONT IS EXPECTED TO LOWER TO MVFR
AROUND 2500 FEET BETWEEN 21Z THU AND 03Z FRI. EXPECT VFR TO
PREVAIL IN POST FRONTAL SHOWERS TONIGHT. BUT THERE MAY BE
LINGERING MVFR CONDITIONS TOWARD THE MOUNTAINS. /27

&&

.MARINE...A FRONTAL SYSTEM IS CURRENTLY PUSHING THROUGH THE
COASTAL WATERS THIS MORNING...SPREADING SMALL CRAFT ADVISORY WINDS
WITH GUSTS TO 25 KT SOONER THIS MORNING ACROSS THE WATERS. HAVE
CHANGED THE SMALL CRAFT ADVISORY TO WINDS TO REFLECT THE EARLIER
TIME FRAME...BUT WINDS STILL LOOK ON TRACK TO END BETWEEN 21Z THU
-00Z FRI. MODELS HAVE BACKED OFF A BIT ON THE STRENGTH OF A
COASTAL JET EXPECTED TO SET UP OVER THE INNER COASTAL WATERS
MIDDAY TODAY...WITH THE MAIN THREAT OVER THE NORTHERN INNER
WATERS. THE SOUTHERN INNER WATERS MAY HAVE A BRIEF PERIOD OF WINDS
GUSTING TO AROUND 25 KT AROUND MIDDAY. WINDS QUICKLY SIMMER DOWN
BY THE EVENING HOURS ONCE THE FRONT PUSHES INLAND.

SEAS WILL HAVE A DIP THIS MORNING AROUND 7 FT BUT PICK TO 10-12
FT TONIGHT INTO FRIDAY...PEAKING AROUND 13 FT LATE TONIGHT AND
FRI. BUOY 05 HAS BEEN AROUND 10 TO 11 FT THIS MORNING...WITH
CORRESPONDS WELL WITH MODELS. MODELS HAVE PUSHED BACK ON THE
TIMING OF THE INCOMING HIGHER SEAS UNTIL CLOSER TO 06Z FRI FOR THE
OUTER WATERS AND CLOSER TO 12Z FRI FOR THE INNER WATERS.

12Z MODELS HAVE ALSO TONED DOWN ON THE FRONTAL PASSAGES FRIDAY
NIGHT INTO SATURDAY...SO NOT EXPECTING ANY SIGNIFICANT STRONG WIND
THREAT UNTIL SUNDAY AS A WARM FRONT LIFTS OVER THE WATERS SUNDAY
MORNING.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 PM PDT THIS AFTERNOON
     FOR COASTAL WATERS FROM CAPE SHOALWATER TO FLORENCE OUT TO
     60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 11 PM THIS
     EVENING TO 8 PM PDT FRIDAY FOR WATERS FROM CAPE SHOALWATER
     TO FLORENCE FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 7 AM TO 8 PM PDT
     FRIDAY FOR COASTAL WATERS FROM CAPE SHOALWATER TO FLORENCE
     OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10
     AM PDT THIS MORNING...FROM 8 PM TO 11 PM PDT THIS EVENING...
     AND AGAIN FROM 8 AM TO 6 PM PDT FRIDAY.

&&


$$

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 231628
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
925 AM PDT THU APR 23 2015

.SYNOPSIS...AFTER A FRONT BRINGS WIDESPREAD RAIN TO THE AREA
TODAY...EXPECT A COOL AND SHOWERY AIRMASS TO LINGER ACROSS THE AREA
ON FRIDAY AND SATURDAY. A PASSING WARM FRONT MAY BRING ADDITIONAL
LIGHT RAIN TO THE AREA ON SUNDAY...BUT IT LOOKS INCREASINGLY LIKELY
TO REMAIN DRY ACROSS THE AREA. HIGH PRESSURE SHOULD BRING DRIER AND
WARMER WEATHER EARLY NEXT WEEK...WITH MORE WET WEATHER LIKELY EITHER
LATE TUESDAY OR WEDNESDAY.

&&

.SHORT TERM...TONIGHT THROUGH SATURDAY...DOPPLER RADAR SHOWS A LARGE
SWATH OF RAIN MOVING EASTWARD INTO NORTHWEST OREGON THIS MORNING.
WHILE THIS HAS PRIMARILY BEEN VIRGA...THE LOWER ATMOSPHERE IS
BEGINNING TO MOISTEN ENOUGH THAT LIGHT RAIN IS STARTING TO REACH THE
SURFACE. ADDITIONAL SHOWERS OFF THE COAST OF OREGON AND WASHINGTON
APPARENT VIA KLGX RADAR ARE ASSOCIATED WITH THE MAIN FRONT THAT IS
CURRENTLY APPROACHING THE REGION. THIS FRONT AND SHOWER ACTIVITY
WILL SPREAD INLAND MIDDAY AND THIS AFTERNOON.

SUBSIDENCE BEHIND THE FRONT SHOULD PRODUCE A BREAK IN THE WET
WEATHER THIS EVENING AWAY FROM THE HIGHER TERRAIN.
HOWEVER...CONTINUING ONSHORE FLOW WILL ALLOW ADDITIONAL SHOWERS TO
SPREAD INTO THE AREA LATER TONIGHT. INSTABILITY WILL INITIALLY BE
SHALLOW ENOUGH THAT THESE SHOWERS WILL LIKELY REMAIN CONFINED TO THE
COAST...COAST RANGE AND CASCADES...BUT DEEPENING INSTABILTY...FROM
NORTH TO SOUTH...SHOULD EVENTUALLY ALLOW SHOWERS TO SPREAD INTO THE
WILLAMETTE AND LOWER COLUMBIA RIVER VALLEYS OVERNIGHT AND INTO
FRIDAY MORNING. DAYTIME HEATING SHOULD FURTHER ENHANCE SHOWER
ACTIVITY INLAND...BUT THUNDERSTORMS APPEAR VERY UNLIKELY.

SNOW LEVELS SHOULD LOWER SOLIDLY BELOW PASS LEVEL OVERNIGHT. WHILE
WINTER WX ADVISORY CRITERIA SNOW ACCUMULATIONS OF MORE THAN 6 INCHES
APPEAR UNLIKELY AT THE PASSES...THERE WILL LIKELY BE A PERIOD OF
HAZARDOUS TRAVEL OVER THE PASSES FRIDAY MORNING AND DURING ANY OF THE
INTENSE SHOWERS FRIDAY AFTERNOON. WILL PLAN ON HIGHLIGHTING THIS ON
SOCIAL MEDIA.

THE UPPER LEVEL TROUGH RESPONSIBLE FOR SENDING THE FRONT ACROSS THE
AREA TODAY...WILL SLOWLY MEANDER ACROSS THE AREA LATE FRIDAY NIGHT
AND SATURDAY BEFORE DIVING INTO THE GREAT BASIN. INSTABILITY WILL
DEEPEN AS A RESULT...AND EXPECT ADDITIONAL SHOWERS TO SPREAD INTO
THE AREA DURING THIS PERIOD. SOME SHOWERS MAY BE DEEP ENOUGH THAT A
FEW THUNDERSTORMS WILL BE POSSIBLE SO MAINTAINED THE SLIGHT CHANCE
OF THUNDER FOR THE MOST SUSCEPTIBLE LOCATIONS.

SHORTWAVE RIDGING SHOULD LEAD TO SHOWERS ENDING FAIRLY QUICKLY
SATURDAY EVENING...WITH ANOTHER COOL NIGHT IN STORE. MODELS CONTINUE
TO TREND DRIER FOR SUNDAY...BUT SOME ENSEMBLE MEMBERS ARE STILL
HANGING ONTO THE IDEA THAT A WARM FRONT WILL BRING RAIN TO THE AREA.
WILL EVALUATE THIS FURTHER WITH THE AFTERNOON FORECAST PACKAGE.
/NEUMAN


.LONG TERM...SUNDAY THROUGH WEDNESDAY...PREVIOUS DISCUSSION
BELOW...MADE VERY FEW CHANGES TO THE EXTENDED FORECAST...AS THE
OVERALL GIST OF THE FORECAST LOOKS TO BE ON TRACK. THE 00Z ECMWF
JOINED THE GFS/GEM IN STRENGTHENING THE UPPER RIDGE ENOUGH TO DRY OUT
THE VAST MAJORITY OF OUR FORECAST AREA SUNDAY THROUGH TUESDAY.
HOWEVER...THERE IS STILL A SIGNIFICANT NUMBER OF ENSEMBLE MEMBERS
WHICH DIFFER FROM THE 00Z OPERATIONAL GFS/ECMWF/GEM SOLUTIONS. THIS
UNCERTAINTY SHOWS IN GFS ENSEMBLE MOS FORECAST OUTPUT...WITH ENSEMBLE
AVERAGE POPS REMAINING IN THE 30S AND 40S AND A LARGE STANDARD
DEVIATION BETWEEN MEMBERS. THEREFORE WE DECIDED NOT TO ELIMINATE THE
MENTION OF RAIN FOR SUNDAY JUST YET. HOWEVER IF MODELS CONTINUE TO
TREND IN THE DIRECTION THEY HAVE BEEN MOVING...SUNDAY COULD BE A MILD
AND DRY DAY ACROSS MUCH OF OUR CWA...WITH A SWING BACK TO ABOVE
NORMAL TEMPS MON AND POSSIBLY TUE. MODEL CONSENSUS SHOWS NEXT FRONT
ARRIVING SOMETIME MIDWEEK...THOUGH TIMING DETAILS VARY BETWEEN
MODELS.  WEAGLE


&&

.AVIATION...MOSTLY VFR CONDITIONS AS A FRONTAL SYSTEM BRINGS LIGHT
RAIN AND OCCASIONAL MVFR CIGS TO THE REGION TODAY. EXPECT A PERIOD
OF WIDESPREAD MVFR CIGS AS THE FRONT MOVES ONSHORE LATE THIS
MORNING INTO THIS AFTERNOON AROUND 20Z THU-02Z FRI. COASTAL AREAS
LIKELY TO HAVE A LONGER PERIOD OF LOWERED FLIGHT CONDITIONS.
CONDITIONS IMPROVING WITH POST FRONTAL SHOWERS TONIGHT. HOWEVER
MOUNTAINS LIKELY BECOMING OBSCURED WITH AND AFTER THE FRONT MOVES
THROUGH.

KPDX AND APPROACHES...VFR WITH A MID CLOUD DECK AROUND 5000 TO
7000 FT WELL AHEAD OF THE FRONT IS EXPECTED TO LOWER TO MVFR
AROUND 2500 FEET BETWEEN 21Z THU AND 03Z FRI. EXPECT VFR TO
PREVAIL IN POST FRONTAL SHOWERS TONIGHT. BUT THERE MAY BE
LINGERING MVFR CONDITIONS TOWARD THE MOUNTAINS. /27

&&

.MARINE...A FRONTAL SYSTEM IS CURRENTLY PUSHING THROUGH THE
COASTAL WATERS THIS MORNING...SPREADING SMALL CRAFT ADVISORY WINDS
WITH GUSTS TO 25 KT SOONER THIS MORNING ACROSS THE WATERS. HAVE
CHANGED THE SMALL CRAFT ADVISORY TO WINDS TO REFLECT THE EARLIER
TIME FRAME...BUT WINDS STILL LOOK ON TRACK TO END BETWEEN 21Z THU
-00Z FRI. MODELS HAVE BACKED OFF A BIT ON THE STRENGTH OF A
COASTAL JET EXPECTED TO SET UP OVER THE INNER COASTAL WATERS
MIDDAY TODAY...WITH THE MAIN THREAT OVER THE NORTHERN INNER
WATERS. THE SOUTHERN INNER WATERS MAY HAVE A BRIEF PERIOD OF WINDS
GUSTING TO AROUND 25 KT AROUND MIDDAY. WINDS QUICKLY SIMMER DOWN
BY THE EVENING HOURS ONCE THE FRONT PUSHES INLAND.

SEAS WILL HAVE A DIP THIS MORNING AROUND 7 FT BUT PICK TO 10-12
FT TONIGHT INTO FRIDAY...PEAKING AROUND 13 FT LATE TONIGHT AND
FRI. BUOY 05 HAS BEEN AROUND 10 TO 11 FT THIS MORNING...WITH
CORRESPONDS WELL WITH MODELS. MODELS HAVE PUSHED BACK ON THE
TIMING OF THE INCOMING HIGHER SEAS UNTIL CLOSER TO 06Z FRI FOR THE
OUTER WATERS AND CLOSER TO 12Z FRI FOR THE INNER WATERS.

12Z MODELS HAVE ALSO TONED DOWN ON THE FRONTAL PASSAGES FRIDAY
NIGHT INTO SATURDAY...SO NOT EXPECTING ANY SIGNIFICANT STRONG WIND
THREAT UNTIL SUNDAY AS A WARM FRONT LIFTS OVER THE WATERS SUNDAY
MORNING.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 PM PDT THIS AFTERNOON
     FOR COASTAL WATERS FROM CAPE SHOALWATER TO FLORENCE OUT TO
     60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 11 PM THIS
     EVENING TO 8 PM PDT FRIDAY FOR WATERS FROM CAPE SHOALWATER
     TO FLORENCE FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 7 AM TO 8 PM PDT
     FRIDAY FOR COASTAL WATERS FROM CAPE SHOALWATER TO FLORENCE
     OUT 10 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 10
     AM PDT THIS MORNING...FROM 8 PM TO 11 PM PDT THIS EVENING...
     AND AGAIN FROM 8 AM TO 6 PM PDT FRIDAY.

&&


$$

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 231036
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
335 AM PDT THU APR 23 2015

.SYNOPSIS...AN OCCLUDING LOW PRESSURE SYSTEM OFF THE BRITISH COLUMBIA
COAST WILL PUSH A WEAK FRONT ONTO THE SW WASHINGTON AND NW OREGON
COAST THIS MORNING AND THROUGH THE INTERIOR DURING THE AFTERNOON AND
EVENING. THE UPPER LOW WILL SLOWLY DRIFT SE OVER THE NEXT COUPLE OF
DAYS...BRINGING SHOWER CHANCES THROUGH SATURDAY ALONG WITH BELOW
NORMAL TEMPERATURES AND SOME SNOW FOR THE CASCADES. A WARM FRONT MAY
BRING MORE RAIN ON SUNDAY...WITH THE BEST CHANCES ALONG THE NORTHERN
COASTAL AREAS. HIGH PRESSURE WILL LIKELY BRING DRIER AND WARMER
WEATHER MONDAY AND TUESDAY...WITH A CHANCE OF RAIN RETURNING TOWARD
THE MIDDLE OF NEXT WEEK AS THE NEXT FRONT APPROACHES.

&&

.SHORT TERM...TODAY THROUGH SATURDAY...LANGLEY HILL NWS DOPPLER RADAR
IS BEGINNING TO PICK UP SOME ECHOES THIS MORNING...AS RAIN ASSOCIATED
WITH OUR INCOMING FRONTAL SYSTEM APPROACHES THE WA COAST. SOME MID TO
HIGH-LEVEL CLOUDS ARE ALREADY STARTING TO SPREAD ONSHORE AHEAD OF THE
FRONT...MITIGATING THE FOG THREAT FOR MOST OF OUR FORECAST AREA.

THE FRONT IS BEING HURRIED ALONG BY A FAIRLY ZONAL 100 KT JET AIMED
TOWARD THE OREGON COAST. THEREFORE EXPECT RAIN TO SPREAD ONSHORE
ALONG THE NORTH COAST THIS MORNING...THEN SPREAD INLAND AND SOUTH
THROUGHOUT THE DAY. WHILE THE PARENT LOW TO THIS FRONT HAS OCCLUDED
OFF THE BC COAST AND WILL LIKELY WEAKEN OVER THE NEXT 12-24 HOURS...
THE JET POSITION IS FAVORABLE FOR A WEAK SECONDARY LOW TO DEVELOP
ALONG THE TRIPLE POINT OF THE OCCLUDING FRONT APPROACHING THE PAC NW
COAST. THIS SHOULD GIVE THE OTHERWISE WEAKENING FRONTAL SYSTEM A
LITTLE EXTRA KICK...WHICH SHOULD BE ENOUGH TO PRODUCE MEASURABLE
RAIN ACROSS MOST OF OUR DISTRICT TODAY. THERE IS ALSO A DECENT PLUME
OF MOISTURE BECOMING ENTRAINED INTO THE FRONT AS IT APPROACHES THE
PAC NW COAST...WITH PW VALUES UPWARDS OF 1 INCH. SUSPECT THIS FRONT
WILL PRODUCE 0.33-0.75 INCH OF RAIN FOR OUR NORTH COAST AND COAST
RANGE ZONE...AND AROUND 0.10-0.25 INCH FOR OUR NORTHERN VALLEYS.
SNOW LEVELS WILL START OFF NEAR OR JUST ABOVE PASS LEVEL...AND THE
AFTERNOON TIMING OF HEAVIEST PRECIPITATION WILL NOT BE CONDUCIVE FOR
MUCH MORE THAN A SLUSHY INCH OR TWO FOR THE PASSES. HIGHER
ELEVATIONS COULD PICK UP 2-5 INCHES OF SNOW THIS AFTERNOON AND
EVENING...GENERALLY WELL BELOW ADVISORY CRITERIA.

COOL GULF OF ALASKA AIR WILL PUSH IN BEHIND THE FRONT...LOWERING THE
SNOW LEVEL TO AROUND 3000-3500 FT LATER TONIGHT AND FRIDAY. HOWEVER
OROGRAPHICS ARE MODEST BEHIND THE FRONT...SO SNOW SHOWERS WILL
PROBABLY ONLY AMOUNT TO COUPLE MORE INCHES IN THE CASCADES TONIGHT
AND FRIDAY. ONSHORE FLOW AND SHALLOW INSTABILITY WILL CAUSE SHOWERS
TO LINGER IN THE LOWLANDS AS WELL THROUGH FRIDAY.

00Z GFS/NAM/GEM/ECMWF SUGGEST A DISTURBANCE PRESENTLY CROSSING 170W
WILL RACE ACROSS THE NE PACIFIC ON A 120-140 KT JET...LATCHING ONTO
SOME MOISTURE SPEWED POLEWARD BY AN UPPER LOW NW OF HAWAII. MODELS
SEEM TO BE PUSHING THIS SYSTEM FURTHER AND FURTHER SOUTH WITH EACH
SUCCESSIVE RUN...AIMING MORE TOWARD NORTHERN CALIFORNIA. EVEN IF THIS
SYSTEM TRACKS SOUTH OF OUR FORECAST AREA THERE MAY BE ENOUGH
DEFORMATION IN BETWEEN THE UPPER LOW TO OUR NORTH AND THE SYSTEM
MOVING ONSHORE TO OUR SOUTH TO KEEP OCCASIONAL RAIN AND MTN SNOW IN
THE PICTURE ACROSS THE FORECAST AREA THROUGH FRI NIGHT. THEREFORE WE
BLANKETED THE CWA WITH LIKELY POPS FRI NIGHT.

THE SOUTHERN DISTURBANCE RACES EASTWARD INTO THE GREAT BASIN SAT...
BUT THE AXIS OF COLD AIR ALOFT ASSOCIATED WITH THE NORTHERN UPPER LOW
WILL LIKELY BE CROSSING WA/OR SATURDAY. THIS SHOULD YIELD ENOUGH
INSTABILITY FOR MORE SHOWERS SATURDAY. ADDED A SLIGHT CHANCE OF
THUNDER TO OUR NORTHERN ZONES AS 00Z/06Z GFS SHOWS 500 MB TEMPS -30
TO -32 DEG C...AND LI/S IN THE ZERO TO -2 DEG C RANGE. MODELS
CONTINUE TO TREND TOWARD BUILDING A RIDGE IN FROM OUR SOUTHWEST LATER
SATURDAY...WHICH MAY CAP CONVECTION LATE IN THE AFTERNOON AS THE AIR
MASS BEGINS TO WARM ALOFT. SHOWERS LIKELY COME TO A QUICK END AFTER
SUNSET SATURDAY AS HIGH PRESSURE BUILDS IN AND THE WARM AIR ALOFT
STABILIZES THE ATMOSPHERE.

TEMPS WILL REMAIN SEVERAL DEGREES BELOW NORMAL THROUGH SATURDAY DUE
TO THE INFLUENCE OF COOL MARITIME AIR FROM THE GULF OF ALASKA. LOWS
SAT NIGHT MAY DIP DOWN INTO THE 30S IN THE VALLEYS ONCE AGAIN IF
SKIES CLEAR FOR OPTIMAL RADIATIONAL COOLING CONDITIONS.  WEAGLE

.LONG TERM...SUNDAY THROUGH WEDNESDAY...MADE VERY FEW CHANGES TO THE
EXTENDED FORECAST...AS THE OVERALL GIST OF THE FORECAST LOOKS TO BE
ON TRACK. THE 00Z ECMWF JOINED THE GFS/GEM IN STRENGTHENING THE UPPER
RIDGE ENOUGH TO DRY OUT THE VAST MAJORITY OF OUR FORECAST AREA SUNDAY
THROUGH TUESDAY. HOWEVER...THERE IS STILL A SIGNIFICANT NUMBER OF
ENSEMBLE MEMBERS WHICH DIFFER FROM THE 00Z OPERATIONAL GFS/ECMWF/GEM
SOLUTIONS. THIS UNCERTAINTY SHOWS IN GFS ENSEMBLE MOS FORECAST
OUTPUT...WITH ENSEMBLE AVERAGE POPS REMAINING IN THE 30S AND 40S AND
A LARGE STANDARD DEVIATION BETWEEN MEMBERS. THEREFORE WE DECIDED NOT
TO ELIMINATE THE MENTION OF RAIN FOR SUNDAY JUST YET. HOWEVER IF
MODELS CONTINUE TO TREND IN THE DIRECTION THEY HAVE BEEN
MOVING...SUNDAY COULD BE A MILD AND DRY DAY ACROSS MUCH OF OUR
CWA...WITH A SWING BACK TO ABOVE NORMAL TEMPS MON AND POSSIBLY TUE.
MODEL CONSENSUS SHOWS NEXT FRONT ARRIVING SOMETIME MIDWEEK...THOUGH
TIMING DETAILS VARY BETWEEN MODELS.  WEAGLE

KEPT THE PREVIOUS LONG TERM DISCUSSION BELOW TO ILLUSTRATE HOW MODELS
HAVE BEEN EVOLVING...

AFTER A FEW DAYS OF POOR CONSISTENCY BETWEEN MODELS...THERE APPEARS
TO BE MARKED IMPROVEMENT IN INTERMODEL CONSISTENCY TODAY WITH THE 12Z
RUNS. GENERAL TREND IS FOR A RIDGE TO BUILD OVER THE PACIFIC NW SUN
AND MON...THEN HAVE THE RIDGE SHIFT E TUE AND WED ALLOWING A DEEP E
PAC TROUGH TO APPROACH THE COAST. ON SUN ECMWF TENDS TO EXTEND THE
EFFECTS OF A WARM FRONT FURTHER S THROUGH THE FORECAST AREA THAN THE
GFS...WITH THE GFS WARM FRONT JUST GRAZING THE NW PART OF THE
FORECAST AREA. WILL NEED TO TAPER POPS FROM CHANCE CATEGORY SUN OVER
THE SE TO LIKELY OR BETTER OVER THE NW. AS THE RIDGE BUILDS CHANCES
FOR RAIN WILL RETREAT FURTHER N SUN NIGHT AND MON MORNING... THEN
DRY WEATHER IS LIKELY TO FOLLOW THROUGH AT LEAST TUE MORNING. GIVEN
INCREASED CONFIDENCE...WILL TRY TO BE MORE BINARY WITH POPS THROUGH
MON NIGHT. WILL ALSO NEED TO RAISE TEMPS FOR MON AND TUE AT THE
HEIGHT OF THE STRENGTH OF THE RIDGE...ALTHOUGH IF INITIAL LOW LEVEL
ONSHORE FLOW BEGINS ANY QUICKER THAN GFS SHOWS TEMPS TUE MAY NOT BE
QUITE SO WARM AS OTHERWISE SUGGESTED.

GFS TENDING TO BE QUICKER THAN ECWMF TO LIFT THE INITIAL SHORTWAVE
TROUGH UP TO THE COAST TUE EVENING. SOUTHERLY FLOW ALOFT AND
INCREASING DEWPOINTS IN THE ACCOMPANYING ONSHORE FLOW SUGGEST SOME
THREAT FOR CONVECTION AHEAD OF THE INITIAL SHORTWAVE PARTICULARLY
OVER THE OREGON CASCADES. GIVEN THAT THIS WILL BE THE FIRST SYSTEM
MOVING INTO THE RIDGE...AND MODEL DIFFERENCES IN TIMING WILL BE A
BIT CONSERVATIVE WITH POPS FROM TUE AFTERNOON ON...LIMITING THEM TO
CHANCE CATEGORY.

&&

.AVIATION...PACIFIC FRONT APPROACHING THE COAST MOVES THROUGH
AROUND MIDDAY FOR THE COAST AND MID TO LATE AFTERNOON INLAND. VFR
CONDITIONS EXPECTED WITH A SEVERAL HOURS OF MVFR CIGS AND POSSIBLY
VISIBILITY REDUCTION AS THE FRONT NEARS AND MOVES THROUGH. COASTAL
AREAS LIKELY TO HAVE A LONGER PERIOD OF LOWERED FLIGHT CONDITIONS.
CONDITIONS IMPROVING WITH POST FRONTAL SHOWERS TONIGHT. HOWEVER
MOUNTAINS LIKELY BECOMING OBSCURED WITH AND AFTER THE FRONT MOVES
THROUGH.

KPDX AND APPROACHES...VFR WITH A MID CLOUD DECK AROUND 5000 TO
7000 FT WELL AHEAD OF THE FRONT IS EXPECTED TO LOWER TO MVFR
AROUND 2500 FEET BETWEEN 21Z THU AND 03Z FRI. EXPECT VFR TO
PREVAIL IN POST FRONTAL SHOWERS TONIGHT. BUT THERE MAY BE
LINGERING MVFR CONDITIONS TOWARD THE MOUNTAINS.  /26

&&

.MARINE...FORECAST LOOKS TO BE ON TRACK WITH PACIFIC FRONT
ASSOCIATED WITH LOW IN THE GULF OF AK MOVING THROUGH THE WATERS
TODAY. AS EARLIER MENTIONED WILL PROBABLY SEE A COASTAL JET SET
UP OVER THE INNER COASTAL WATERS MIDDAY THURSDAY...WITH THE MAIN
THREAT OVER THE NORTHERN INNER WATERS. THE SOUTHERN INNER WATERS
MAY HAVE A BRIEF PERIOD OF WINDS GUSTING TO AROUND 25 KT AROUND
MIDDAY. WINDS QUICKLY SIMMER DOWN BY THE EVENING HOURS ONCE THE
FRONT PUSHES INLAND. SEAS WILL HAVE A DIP THIS MORNING AROUND 7
FT BUT PICK TO 10-12 FT TONIGHT INTO FRIDAY...PEAKING AROUND 13 FT
LATE TONIGHT AND FRI.

12Z MODELS HAVE ALSO TONED DOWN ON THE FRONTAL PASSAGES FRIDAY
NIGHT INTO SATURDAY...SO NOT EXPECTING ANY SIGNIFICANT STRONG WIND
THREAT UNTIL SUNDAY AS A WARM FRONT LIFTS OVER THE WATERS SUNDAY
MORNING.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM THIS MORNING TO 5 PM
     PDT THIS AFTERNOON 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 5 PM THIS
     AFTERNOON TO 8 PM PDT FRIDAY 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 WINDS FROM 11 AM THIS MORNING TO 5 PM
     PDT THIS AFTERNOON FOR COASTAL WATERS FROM CAPE SHOALWATER
     WA TO CASCADE HEAD OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 3 AM TO 8 PM PDT
     FRIDAY 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 THIS MORNING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     8 PM TO 11 PM PDT THIS EVENING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     8 AM TO 6 PM PDT FRIDAY.

&&


$$

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 231036
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
335 AM PDT THU APR 23 2015

.SYNOPSIS...AN OCCLUDING LOW PRESSURE SYSTEM OFF THE BRITISH COLUMBIA
COAST WILL PUSH A WEAK FRONT ONTO THE SW WASHINGTON AND NW OREGON
COAST THIS MORNING AND THROUGH THE INTERIOR DURING THE AFTERNOON AND
EVENING. THE UPPER LOW WILL SLOWLY DRIFT SE OVER THE NEXT COUPLE OF
DAYS...BRINGING SHOWER CHANCES THROUGH SATURDAY ALONG WITH BELOW
NORMAL TEMPERATURES AND SOME SNOW FOR THE CASCADES. A WARM FRONT MAY
BRING MORE RAIN ON SUNDAY...WITH THE BEST CHANCES ALONG THE NORTHERN
COASTAL AREAS. HIGH PRESSURE WILL LIKELY BRING DRIER AND WARMER
WEATHER MONDAY AND TUESDAY...WITH A CHANCE OF RAIN RETURNING TOWARD
THE MIDDLE OF NEXT WEEK AS THE NEXT FRONT APPROACHES.

&&

.SHORT TERM...TODAY THROUGH SATURDAY...LANGLEY HILL NWS DOPPLER RADAR
IS BEGINNING TO PICK UP SOME ECHOES THIS MORNING...AS RAIN ASSOCIATED
WITH OUR INCOMING FRONTAL SYSTEM APPROACHES THE WA COAST. SOME MID TO
HIGH-LEVEL CLOUDS ARE ALREADY STARTING TO SPREAD ONSHORE AHEAD OF THE
FRONT...MITIGATING THE FOG THREAT FOR MOST OF OUR FORECAST AREA.

THE FRONT IS BEING HURRIED ALONG BY A FAIRLY ZONAL 100 KT JET AIMED
TOWARD THE OREGON COAST. THEREFORE EXPECT RAIN TO SPREAD ONSHORE
ALONG THE NORTH COAST THIS MORNING...THEN SPREAD INLAND AND SOUTH
THROUGHOUT THE DAY. WHILE THE PARENT LOW TO THIS FRONT HAS OCCLUDED
OFF THE BC COAST AND WILL LIKELY WEAKEN OVER THE NEXT 12-24 HOURS...
THE JET POSITION IS FAVORABLE FOR A WEAK SECONDARY LOW TO DEVELOP
ALONG THE TRIPLE POINT OF THE OCCLUDING FRONT APPROACHING THE PAC NW
COAST. THIS SHOULD GIVE THE OTHERWISE WEAKENING FRONTAL SYSTEM A
LITTLE EXTRA KICK...WHICH SHOULD BE ENOUGH TO PRODUCE MEASURABLE
RAIN ACROSS MOST OF OUR DISTRICT TODAY. THERE IS ALSO A DECENT PLUME
OF MOISTURE BECOMING ENTRAINED INTO THE FRONT AS IT APPROACHES THE
PAC NW COAST...WITH PW VALUES UPWARDS OF 1 INCH. SUSPECT THIS FRONT
WILL PRODUCE 0.33-0.75 INCH OF RAIN FOR OUR NORTH COAST AND COAST
RANGE ZONE...AND AROUND 0.10-0.25 INCH FOR OUR NORTHERN VALLEYS.
SNOW LEVELS WILL START OFF NEAR OR JUST ABOVE PASS LEVEL...AND THE
AFTERNOON TIMING OF HEAVIEST PRECIPITATION WILL NOT BE CONDUCIVE FOR
MUCH MORE THAN A SLUSHY INCH OR TWO FOR THE PASSES. HIGHER
ELEVATIONS COULD PICK UP 2-5 INCHES OF SNOW THIS AFTERNOON AND
EVENING...GENERALLY WELL BELOW ADVISORY CRITERIA.

COOL GULF OF ALASKA AIR WILL PUSH IN BEHIND THE FRONT...LOWERING THE
SNOW LEVEL TO AROUND 3000-3500 FT LATER TONIGHT AND FRIDAY. HOWEVER
OROGRAPHICS ARE MODEST BEHIND THE FRONT...SO SNOW SHOWERS WILL
PROBABLY ONLY AMOUNT TO COUPLE MORE INCHES IN THE CASCADES TONIGHT
AND FRIDAY. ONSHORE FLOW AND SHALLOW INSTABILITY WILL CAUSE SHOWERS
TO LINGER IN THE LOWLANDS AS WELL THROUGH FRIDAY.

00Z GFS/NAM/GEM/ECMWF SUGGEST A DISTURBANCE PRESENTLY CROSSING 170W
WILL RACE ACROSS THE NE PACIFIC ON A 120-140 KT JET...LATCHING ONTO
SOME MOISTURE SPEWED POLEWARD BY AN UPPER LOW NW OF HAWAII. MODELS
SEEM TO BE PUSHING THIS SYSTEM FURTHER AND FURTHER SOUTH WITH EACH
SUCCESSIVE RUN...AIMING MORE TOWARD NORTHERN CALIFORNIA. EVEN IF THIS
SYSTEM TRACKS SOUTH OF OUR FORECAST AREA THERE MAY BE ENOUGH
DEFORMATION IN BETWEEN THE UPPER LOW TO OUR NORTH AND THE SYSTEM
MOVING ONSHORE TO OUR SOUTH TO KEEP OCCASIONAL RAIN AND MTN SNOW IN
THE PICTURE ACROSS THE FORECAST AREA THROUGH FRI NIGHT. THEREFORE WE
BLANKETED THE CWA WITH LIKELY POPS FRI NIGHT.

THE SOUTHERN DISTURBANCE RACES EASTWARD INTO THE GREAT BASIN SAT...
BUT THE AXIS OF COLD AIR ALOFT ASSOCIATED WITH THE NORTHERN UPPER LOW
WILL LIKELY BE CROSSING WA/OR SATURDAY. THIS SHOULD YIELD ENOUGH
INSTABILITY FOR MORE SHOWERS SATURDAY. ADDED A SLIGHT CHANCE OF
THUNDER TO OUR NORTHERN ZONES AS 00Z/06Z GFS SHOWS 500 MB TEMPS -30
TO -32 DEG C...AND LI/S IN THE ZERO TO -2 DEG C RANGE. MODELS
CONTINUE TO TREND TOWARD BUILDING A RIDGE IN FROM OUR SOUTHWEST LATER
SATURDAY...WHICH MAY CAP CONVECTION LATE IN THE AFTERNOON AS THE AIR
MASS BEGINS TO WARM ALOFT. SHOWERS LIKELY COME TO A QUICK END AFTER
SUNSET SATURDAY AS HIGH PRESSURE BUILDS IN AND THE WARM AIR ALOFT
STABILIZES THE ATMOSPHERE.

TEMPS WILL REMAIN SEVERAL DEGREES BELOW NORMAL THROUGH SATURDAY DUE
TO THE INFLUENCE OF COOL MARITIME AIR FROM THE GULF OF ALASKA. LOWS
SAT NIGHT MAY DIP DOWN INTO THE 30S IN THE VALLEYS ONCE AGAIN IF
SKIES CLEAR FOR OPTIMAL RADIATIONAL COOLING CONDITIONS.  WEAGLE

.LONG TERM...SUNDAY THROUGH WEDNESDAY...MADE VERY FEW CHANGES TO THE
EXTENDED FORECAST...AS THE OVERALL GIST OF THE FORECAST LOOKS TO BE
ON TRACK. THE 00Z ECMWF JOINED THE GFS/GEM IN STRENGTHENING THE UPPER
RIDGE ENOUGH TO DRY OUT THE VAST MAJORITY OF OUR FORECAST AREA SUNDAY
THROUGH TUESDAY. HOWEVER...THERE IS STILL A SIGNIFICANT NUMBER OF
ENSEMBLE MEMBERS WHICH DIFFER FROM THE 00Z OPERATIONAL GFS/ECMWF/GEM
SOLUTIONS. THIS UNCERTAINTY SHOWS IN GFS ENSEMBLE MOS FORECAST
OUTPUT...WITH ENSEMBLE AVERAGE POPS REMAINING IN THE 30S AND 40S AND
A LARGE STANDARD DEVIATION BETWEEN MEMBERS. THEREFORE WE DECIDED NOT
TO ELIMINATE THE MENTION OF RAIN FOR SUNDAY JUST YET. HOWEVER IF
MODELS CONTINUE TO TREND IN THE DIRECTION THEY HAVE BEEN
MOVING...SUNDAY COULD BE A MILD AND DRY DAY ACROSS MUCH OF OUR
CWA...WITH A SWING BACK TO ABOVE NORMAL TEMPS MON AND POSSIBLY TUE.
MODEL CONSENSUS SHOWS NEXT FRONT ARRIVING SOMETIME MIDWEEK...THOUGH
TIMING DETAILS VARY BETWEEN MODELS.  WEAGLE

KEPT THE PREVIOUS LONG TERM DISCUSSION BELOW TO ILLUSTRATE HOW MODELS
HAVE BEEN EVOLVING...

AFTER A FEW DAYS OF POOR CONSISTENCY BETWEEN MODELS...THERE APPEARS
TO BE MARKED IMPROVEMENT IN INTERMODEL CONSISTENCY TODAY WITH THE 12Z
RUNS. GENERAL TREND IS FOR A RIDGE TO BUILD OVER THE PACIFIC NW SUN
AND MON...THEN HAVE THE RIDGE SHIFT E TUE AND WED ALLOWING A DEEP E
PAC TROUGH TO APPROACH THE COAST. ON SUN ECMWF TENDS TO EXTEND THE
EFFECTS OF A WARM FRONT FURTHER S THROUGH THE FORECAST AREA THAN THE
GFS...WITH THE GFS WARM FRONT JUST GRAZING THE NW PART OF THE
FORECAST AREA. WILL NEED TO TAPER POPS FROM CHANCE CATEGORY SUN OVER
THE SE TO LIKELY OR BETTER OVER THE NW. AS THE RIDGE BUILDS CHANCES
FOR RAIN WILL RETREAT FURTHER N SUN NIGHT AND MON MORNING... THEN
DRY WEATHER IS LIKELY TO FOLLOW THROUGH AT LEAST TUE MORNING. GIVEN
INCREASED CONFIDENCE...WILL TRY TO BE MORE BINARY WITH POPS THROUGH
MON NIGHT. WILL ALSO NEED TO RAISE TEMPS FOR MON AND TUE AT THE
HEIGHT OF THE STRENGTH OF THE RIDGE...ALTHOUGH IF INITIAL LOW LEVEL
ONSHORE FLOW BEGINS ANY QUICKER THAN GFS SHOWS TEMPS TUE MAY NOT BE
QUITE SO WARM AS OTHERWISE SUGGESTED.

GFS TENDING TO BE QUICKER THAN ECWMF TO LIFT THE INITIAL SHORTWAVE
TROUGH UP TO THE COAST TUE EVENING. SOUTHERLY FLOW ALOFT AND
INCREASING DEWPOINTS IN THE ACCOMPANYING ONSHORE FLOW SUGGEST SOME
THREAT FOR CONVECTION AHEAD OF THE INITIAL SHORTWAVE PARTICULARLY
OVER THE OREGON CASCADES. GIVEN THAT THIS WILL BE THE FIRST SYSTEM
MOVING INTO THE RIDGE...AND MODEL DIFFERENCES IN TIMING WILL BE A
BIT CONSERVATIVE WITH POPS FROM TUE AFTERNOON ON...LIMITING THEM TO
CHANCE CATEGORY.

&&

.AVIATION...PACIFIC FRONT APPROACHING THE COAST MOVES THROUGH
AROUND MIDDAY FOR THE COAST AND MID TO LATE AFTERNOON INLAND. VFR
CONDITIONS EXPECTED WITH A SEVERAL HOURS OF MVFR CIGS AND POSSIBLY
VISIBILITY REDUCTION AS THE FRONT NEARS AND MOVES THROUGH. COASTAL
AREAS LIKELY TO HAVE A LONGER PERIOD OF LOWERED FLIGHT CONDITIONS.
CONDITIONS IMPROVING WITH POST FRONTAL SHOWERS TONIGHT. HOWEVER
MOUNTAINS LIKELY BECOMING OBSCURED WITH AND AFTER THE FRONT MOVES
THROUGH.

KPDX AND APPROACHES...VFR WITH A MID CLOUD DECK AROUND 5000 TO
7000 FT WELL AHEAD OF THE FRONT IS EXPECTED TO LOWER TO MVFR
AROUND 2500 FEET BETWEEN 21Z THU AND 03Z FRI. EXPECT VFR TO
PREVAIL IN POST FRONTAL SHOWERS TONIGHT. BUT THERE MAY BE
LINGERING MVFR CONDITIONS TOWARD THE MOUNTAINS.  /26

&&

.MARINE...FORECAST LOOKS TO BE ON TRACK WITH PACIFIC FRONT
ASSOCIATED WITH LOW IN THE GULF OF AK MOVING THROUGH THE WATERS
TODAY. AS EARLIER MENTIONED WILL PROBABLY SEE A COASTAL JET SET
UP OVER THE INNER COASTAL WATERS MIDDAY THURSDAY...WITH THE MAIN
THREAT OVER THE NORTHERN INNER WATERS. THE SOUTHERN INNER WATERS
MAY HAVE A BRIEF PERIOD OF WINDS GUSTING TO AROUND 25 KT AROUND
MIDDAY. WINDS QUICKLY SIMMER DOWN BY THE EVENING HOURS ONCE THE
FRONT PUSHES INLAND. SEAS WILL HAVE A DIP THIS MORNING AROUND 7
FT BUT PICK TO 10-12 FT TONIGHT INTO FRIDAY...PEAKING AROUND 13 FT
LATE TONIGHT AND FRI.

12Z MODELS HAVE ALSO TONED DOWN ON THE FRONTAL PASSAGES FRIDAY
NIGHT INTO SATURDAY...SO NOT EXPECTING ANY SIGNIFICANT STRONG WIND
THREAT UNTIL SUNDAY AS A WARM FRONT LIFTS OVER THE WATERS SUNDAY
MORNING.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 7 AM THIS MORNING TO 5 PM
     PDT THIS AFTERNOON 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 5 PM THIS
     AFTERNOON TO 8 PM PDT FRIDAY 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 WINDS FROM 11 AM THIS MORNING TO 5 PM
     PDT THIS AFTERNOON FOR COASTAL WATERS FROM CAPE SHOALWATER
     WA TO CASCADE HEAD OR OUT 10 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 3 AM TO 8 PM PDT
     FRIDAY 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 THIS MORNING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     8 PM TO 11 PM PDT THIS EVENING.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM
     8 AM TO 6 PM PDT FRIDAY.

&&


$$

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.




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