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000
FXUS66 KPQR 291608 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
908 AM PDT FRI MAY 29 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. MEANWHILE...A CLOSED UPPER LEVEL LOW WILL MOVE INTO
BRITISH COLUMBIA. DESPITE WEST FLOW ALOFT...THERE WILL BE ENOUGH
RESIDUAL INSTABILITY OVER THE HIGHER CASCADES TODAY FOR A CONTINUED
THREAT OF LATE-DAY THUNDERSTORMS. THE UPPER RIDGE STARTS TO FLATTEN
TODAY...BUT IS EXPECTED TO STRENGTHEN A LITTLE SATURDAY. ANY
THUNDERSTORM THREAT SATURDAY SHOULD BE CONFINED TO THE SOUTHERN LANE
COUNTY CASCADES. THE NEXT UPPER LOW SWINGS  TOWARD THE OREGON COAST
SUNDAY...RESULTING IN A LITTLE MORE COOLING BUT A BETTER CHANCE OF
CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE LAYER IS EXPECTED OVER
THE AREA EARLY NEXT WEEK.

&&

.UPDATE...VISIBLE SATELLITE IMAGERY THIS MORNING SHOWS LOW MARINE
STRATUS ALONG THE COAST AND PUSHING INTO THE COAST RANGE VALLEYS AND
UP THE COLUMBIA TO WEST OF PORTLAND. SW WINDS IN THE SOUTH VALLEY
AROUND EUGENE HAVE BROUGHT SOME MARINE AIR IN THERE AND WILL KEEP
TEMPERATURES DOWN A BIT THIS MORNING. HOWEVER IN THE NORTH VALLEY
THERE IS LESS CLOUD COVER THAN YESTERDAY MORNING SO TEMPERATURES ARE
STARTING OFF A FEW DEGREES WARMER. WITH 850 MB TEMPERATURES NEAR
IDENTICAL TO YESTERDAY...WILL BE INTERESTING TO SEE HOW MUCH MORNING
TEMPERATURES AFFECT AFTERNOON HIGHS OR IF MIXING WILL BE THE MAIN
FACTOR ONCE SKIES CLEAR THIS AFTERNOON. IF MIXING PLAYS THE LARGER
ROLE...EXPECT TEMPERATURES JUST LIKE YESTERDAY INLAND. ALONG THE
COAST...STRATUS WILL REMAIN THROUGH THE DAY...LIMITING HEATING WITH
TEMPERATURES SIMILAR TO YESTERDAY. NUDGED TEMPERATURES UP A SMIDGE IN
THE NORTH VALLEY DUE TO LESS CLOUD COVER THIS MORNING AND DOWN A
SMIDGE IN THE NEWPORT AREA TOWARD YESTERDAY`S HIGHS.

MODELS STILL SHOWING A GOOD AMOUNT OF INSTABILITY THIS AFTERNOON IN
THE CASCADES FOR THUNDERSTORMS. THE NAM IN PARTICULAR IS INCREDIBLY
GUNG HO WITH CAPE BUT TO AN UNREALISTIC EXTENT. THE GFS SEEMS MORE
REASONABLE BUT AM SLIGHTLY CONCERNED WITH THE FACT THAT THE HRRR IS
SHOWING LITTLE TO NO SHOWER OR TSTORM ACTIVITY ALONG THE CREST
THROUGH 05Z SATURDAY. WILL STICK WITH THE CURRENT TSTORM FORECAST FOR
NOW BUT TAKE A GOOD LOOK AT 12Z MODELS AND UPDATES FROM THE HRRR AND
RUC. BOWEN

.SHORT TERM (PREVIOUS DISCUSSION)...TODAY THROUGH SUNDAY...THE
LARGE-SCALE PATTERN REMAINS VIRTUALLY UNCHANGED FROM 24 HOURS AGO.
WATER VAPOR LOOP SHOWS 500 MB HIGH PRES RIDGE AXIS EXTENDING FROM 30N
125W TO A 577 DM HIGH CENTER NEAR 50N 140W. ALSO OF NOTE IS A CLOSED
UPPER LOW ALONG THE CENTRAL BRITISH COLUMBIA COAST AND ANOTHER ONE
OUT AROUND 40N 150W. THIS LATTER LOW IS THE ONE THAT WILL BECOME A
PLAYER FOR OUR WEATHER LATE IN THE WEEKEND.

TODAY LOOKS TO BE A NEAR REPEAT OF YESTERDAY. THE MARINE LAYER HAS
NOT CHANGED ALL THAT MUCH. KKLS REPORTED OVC CONDITIONS AROUND
07Z...SIMILAR TO 24 HOURS AGO. THE NAM AND HI-RES ARW SUGGEST MARINE
STRATUS WILL COME DOWN THE COLUMBIA RIVER AND FILL IN WRN CLARK
COUNTY IN SW WA BY 12Z. THE KAST-KDPX GRADIENT IS SLIGHTLY STRONGER
AT 08Z...2.1 MB...COMPARED TO 08Z THU. THIS IS LIKELY DUE TO THE
WARMER INTERIOR RESULTING IN SLIGHTLY LOWER SFC PRES. MODEL FORECAST
850 MB TEMPS ARE SIMILAR TO THU...MAYBE UP A DEGREE INLAND.
THUS...HAVE NUDGED MAX TEMPS UP A DEGREE OR TWO...BASED ON THU
VALUES. TODAY IS LIKELY TO BE THE WARMEST DAY OF 2015 AT KPDX...IF WE
HIT THE FCST HIGH OF 85.

THE FORECAST PROBLEM CONTINUES TO BE THE THUNDERSTORM THREAT FOR THE
CASCADES. MODELS DID A PRETTY GOOD JOB PIN-POINTING THE CONVECTIVE
THREAT FOR THU...ALONG THE CASCADE CREST. 06Z MODEL SOUNDINGS FOR A
POINT NEAR SANTIAM PASS CONTINUE TO SHOW FAIRLY ROBUST CONVECTIVE
PARAMETERS LATE THIS AFTERNOON. NAM SOUNDING GIVES AN IMPRESSIVE 2800
J/KG SURFACE-BASED CAPE...WITH A ML CAPE NEAR 1450 J/KG. AGAIN...
BELIEVE THE NAM IS OVER-DOING THE SURFACE DEW POINTS. THE GFS
HAS A ML CAPE OF 500 J/KG. GFS 700 MB THETA E RIDGE IS CENTERED ALONG
THE OREGON CASCADE CREST 00Z SAT. A LITTLE LOWER THETA E VALUES IN
THE S WA CASCADES COMPARED TO THU. DECIDED TO EXPAND THE THUNDERSTORM
THREAT JUST A BIT MORE W...BUT STILL KEEPING IT IN THE HIGHER
CASCADES AND NOT THE FOOTHILLS.

FOR SAT THE 500 MB HEIGHTS RISE JUST A BIT AS THE UPPER LOW IN THE
CENTRAL PAC GRADUALLY MIGRATES EAST. THE MAIN IMPACT WILL BE A MORE
STABLE AIR MASS WITH DEEPER WLY FLOW ALOFT. GFS STILL INDICATES SOME
INSTABILITY OVER THE SRN LANE COUNTY CASCADES SAT AFTERNOON AND HAVE
LEFT THE MENTION OF THUNDERSTORMS FOR THAT AREA. MAV AND MET GUIDANCE
INDICATE 2-3 DEGREES COOLING SAT...BUT NOT SURE TO BELIEVE THAT.
MODEL FORECAST 850 MB TEMPS EASE ABOUT A DEGREE...BUT WITH A SLIGHTLY
WARMER START AM EXPECTING MAX TEMPS TO BE CLOSE TO FRI VALUES.

THE FLOW ALOFT BACKS TO THE SW LATE SAT AND SAT NIGHT. THE 500 MB
RIDGE AXIS IS EXPECTED TO BE CENTERED OVER THE FORECAST AREA SAT
NIGHT...THEN SLOWLY SHIFT EAST SUN. NAM CROSS-SECTION FROM KAST
THROUGH THE GORGE SHOWS INCREASING MID AND HIGH LEVEL MOISTURE SUN
AFTERNOON. REDUCED POPS SUN AS MODELS NOT SHOWING DEEPER MOISTURE
DEVELOPING UNTIL LATE SUN AND SUN EVENING. ALSO RAISED INLAND MAX
TEMPS 2-3 DEGREES. PATTERN RECOGNITION WOULD SUGGEST THERE COULD BE
NOCTURNAL THUNDERSTORMS SUN NIGHT...BUT MODEL SOUNDINGS DO NOT
SUPPORT CONVECTION ANYWHERE WEST OF THE CASCADES. WEISHAAR

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THE FIRST AND STRONGEST
UPPER LEVEL TROUGH WILL SLIDE N-NE INTO THE REGION LATE SUNDAY AND
CONTINUE TO ENHANCE SHOWER CHANCES THROUGH THE EARLY PART OF NEXT
WEEK. THE ASSOCIATED FRONT WILL CROSS THE REGION OVERNIGHT PROVIDING
FOR MUCH COOLER HIGH TEMPS ON MONDAY GIVEN THE ABUNDANT CLOUD COVER
AND MODELS SUGGESTING H8 TEMPS DECREASING AROUND 10 DEG C BY MONDAY
MORNING. WHILE MODELS SUGGEST SOME INSTABILITY...PARTICULARLY
TUESDAY AS THE COLD CORE ALOFT MOVES ACROSS THE AREA...THINK MUCH
COOLER SURFACE TEMPERATURES WILL LARGELY LIMIT THUNDER CHANCES.
HOWEVER...THE TIMING OF SHORTWAVE IMPULSES MAY ENHANCE THIS
POTENTIAL AT TIMES BUT CONFIDENCE IN THIS SCENARIO REMAINS LOW
ENOUGH TO EXCLUDE ANY THUNDERSTORMS IN THE EXTENDED PERIOD FOR NOW
WITH THE EXCEPTION OF MAINTAINING A CHANCE FOR MONDAY LATE
AFTERNOON/EVENING IN THE CASCADES SOUTH OF AROUND MT HOOD.
TEMPERATURES LIKELY REBOUND A LITTLE...CLOSER TO SEASONAL
NORMS...FOR THE SECOND HALF OF THE WEEK AS SHOWERS END AND WEAK
SHORTWAVE RIDGING PROVIDING FOR SOME AFTERNOON SUN AFTER MORNING
CLOUDS.  CULLEN
&&

.AVIATION...HIGH CLOUDS CONTINUE ACROSS THE AREA UNDER DRY SW
FLOW ALOFT. IFR STRATUS WILL PERSIST ALONG THE COAST. MARINE
STRATUS ALONG THE COLUMBIA RIVER REACHED KKLS THIS MORNING...BUT
WILL GRADUALLY BURN OFF BY 17Z-19Z THIS MORNING. WILL ALSO HAVE
PATCHY LOW CLOUDS FROM KSLE THROUGH KEUG TO K61S...AND IN
CASCADES TIL 17Z.

KPDX AND APPROACHES...VFR UNDER VARIABLE HIGH CLOUDS. ROCKEY/27

&&

.MARINE...BENIGN CONDITIONS CONTINUE INTO NEXT WEEK...WITH W TO NW
WINDS 15 KT OR LESS AND SEAS RUNNING 4 TO 6 FT. ROCKEY.

&&

.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 291608 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
908 AM PDT FRI MAY 29 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. MEANWHILE...A CLOSED UPPER LEVEL LOW WILL MOVE INTO
BRITISH COLUMBIA. DESPITE WEST FLOW ALOFT...THERE WILL BE ENOUGH
RESIDUAL INSTABILITY OVER THE HIGHER CASCADES TODAY FOR A CONTINUED
THREAT OF LATE-DAY THUNDERSTORMS. THE UPPER RIDGE STARTS TO FLATTEN
TODAY...BUT IS EXPECTED TO STRENGTHEN A LITTLE SATURDAY. ANY
THUNDERSTORM THREAT SATURDAY SHOULD BE CONFINED TO THE SOUTHERN LANE
COUNTY CASCADES. THE NEXT UPPER LOW SWINGS  TOWARD THE OREGON COAST
SUNDAY...RESULTING IN A LITTLE MORE COOLING BUT A BETTER CHANCE OF
CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE LAYER IS EXPECTED OVER
THE AREA EARLY NEXT WEEK.

&&

.UPDATE...VISIBLE SATELLITE IMAGERY THIS MORNING SHOWS LOW MARINE
STRATUS ALONG THE COAST AND PUSHING INTO THE COAST RANGE VALLEYS AND
UP THE COLUMBIA TO WEST OF PORTLAND. SW WINDS IN THE SOUTH VALLEY
AROUND EUGENE HAVE BROUGHT SOME MARINE AIR IN THERE AND WILL KEEP
TEMPERATURES DOWN A BIT THIS MORNING. HOWEVER IN THE NORTH VALLEY
THERE IS LESS CLOUD COVER THAN YESTERDAY MORNING SO TEMPERATURES ARE
STARTING OFF A FEW DEGREES WARMER. WITH 850 MB TEMPERATURES NEAR
IDENTICAL TO YESTERDAY...WILL BE INTERESTING TO SEE HOW MUCH MORNING
TEMPERATURES AFFECT AFTERNOON HIGHS OR IF MIXING WILL BE THE MAIN
FACTOR ONCE SKIES CLEAR THIS AFTERNOON. IF MIXING PLAYS THE LARGER
ROLE...EXPECT TEMPERATURES JUST LIKE YESTERDAY INLAND. ALONG THE
COAST...STRATUS WILL REMAIN THROUGH THE DAY...LIMITING HEATING WITH
TEMPERATURES SIMILAR TO YESTERDAY. NUDGED TEMPERATURES UP A SMIDGE IN
THE NORTH VALLEY DUE TO LESS CLOUD COVER THIS MORNING AND DOWN A
SMIDGE IN THE NEWPORT AREA TOWARD YESTERDAY`S HIGHS.

MODELS STILL SHOWING A GOOD AMOUNT OF INSTABILITY THIS AFTERNOON IN
THE CASCADES FOR THUNDERSTORMS. THE NAM IN PARTICULAR IS INCREDIBLY
GUNG HO WITH CAPE BUT TO AN UNREALISTIC EXTENT. THE GFS SEEMS MORE
REASONABLE BUT AM SLIGHTLY CONCERNED WITH THE FACT THAT THE HRRR IS
SHOWING LITTLE TO NO SHOWER OR TSTORM ACTIVITY ALONG THE CREST
THROUGH 05Z SATURDAY. WILL STICK WITH THE CURRENT TSTORM FORECAST FOR
NOW BUT TAKE A GOOD LOOK AT 12Z MODELS AND UPDATES FROM THE HRRR AND
RUC. BOWEN

.SHORT TERM (PREVIOUS DISCUSSION)...TODAY THROUGH SUNDAY...THE
LARGE-SCALE PATTERN REMAINS VIRTUALLY UNCHANGED FROM 24 HOURS AGO.
WATER VAPOR LOOP SHOWS 500 MB HIGH PRES RIDGE AXIS EXTENDING FROM 30N
125W TO A 577 DM HIGH CENTER NEAR 50N 140W. ALSO OF NOTE IS A CLOSED
UPPER LOW ALONG THE CENTRAL BRITISH COLUMBIA COAST AND ANOTHER ONE
OUT AROUND 40N 150W. THIS LATTER LOW IS THE ONE THAT WILL BECOME A
PLAYER FOR OUR WEATHER LATE IN THE WEEKEND.

TODAY LOOKS TO BE A NEAR REPEAT OF YESTERDAY. THE MARINE LAYER HAS
NOT CHANGED ALL THAT MUCH. KKLS REPORTED OVC CONDITIONS AROUND
07Z...SIMILAR TO 24 HOURS AGO. THE NAM AND HI-RES ARW SUGGEST MARINE
STRATUS WILL COME DOWN THE COLUMBIA RIVER AND FILL IN WRN CLARK
COUNTY IN SW WA BY 12Z. THE KAST-KDPX GRADIENT IS SLIGHTLY STRONGER
AT 08Z...2.1 MB...COMPARED TO 08Z THU. THIS IS LIKELY DUE TO THE
WARMER INTERIOR RESULTING IN SLIGHTLY LOWER SFC PRES. MODEL FORECAST
850 MB TEMPS ARE SIMILAR TO THU...MAYBE UP A DEGREE INLAND.
THUS...HAVE NUDGED MAX TEMPS UP A DEGREE OR TWO...BASED ON THU
VALUES. TODAY IS LIKELY TO BE THE WARMEST DAY OF 2015 AT KPDX...IF WE
HIT THE FCST HIGH OF 85.

THE FORECAST PROBLEM CONTINUES TO BE THE THUNDERSTORM THREAT FOR THE
CASCADES. MODELS DID A PRETTY GOOD JOB PIN-POINTING THE CONVECTIVE
THREAT FOR THU...ALONG THE CASCADE CREST. 06Z MODEL SOUNDINGS FOR A
POINT NEAR SANTIAM PASS CONTINUE TO SHOW FAIRLY ROBUST CONVECTIVE
PARAMETERS LATE THIS AFTERNOON. NAM SOUNDING GIVES AN IMPRESSIVE 2800
J/KG SURFACE-BASED CAPE...WITH A ML CAPE NEAR 1450 J/KG. AGAIN...
BELIEVE THE NAM IS OVER-DOING THE SURFACE DEW POINTS. THE GFS
HAS A ML CAPE OF 500 J/KG. GFS 700 MB THETA E RIDGE IS CENTERED ALONG
THE OREGON CASCADE CREST 00Z SAT. A LITTLE LOWER THETA E VALUES IN
THE S WA CASCADES COMPARED TO THU. DECIDED TO EXPAND THE THUNDERSTORM
THREAT JUST A BIT MORE W...BUT STILL KEEPING IT IN THE HIGHER
CASCADES AND NOT THE FOOTHILLS.

FOR SAT THE 500 MB HEIGHTS RISE JUST A BIT AS THE UPPER LOW IN THE
CENTRAL PAC GRADUALLY MIGRATES EAST. THE MAIN IMPACT WILL BE A MORE
STABLE AIR MASS WITH DEEPER WLY FLOW ALOFT. GFS STILL INDICATES SOME
INSTABILITY OVER THE SRN LANE COUNTY CASCADES SAT AFTERNOON AND HAVE
LEFT THE MENTION OF THUNDERSTORMS FOR THAT AREA. MAV AND MET GUIDANCE
INDICATE 2-3 DEGREES COOLING SAT...BUT NOT SURE TO BELIEVE THAT.
MODEL FORECAST 850 MB TEMPS EASE ABOUT A DEGREE...BUT WITH A SLIGHTLY
WARMER START AM EXPECTING MAX TEMPS TO BE CLOSE TO FRI VALUES.

THE FLOW ALOFT BACKS TO THE SW LATE SAT AND SAT NIGHT. THE 500 MB
RIDGE AXIS IS EXPECTED TO BE CENTERED OVER THE FORECAST AREA SAT
NIGHT...THEN SLOWLY SHIFT EAST SUN. NAM CROSS-SECTION FROM KAST
THROUGH THE GORGE SHOWS INCREASING MID AND HIGH LEVEL MOISTURE SUN
AFTERNOON. REDUCED POPS SUN AS MODELS NOT SHOWING DEEPER MOISTURE
DEVELOPING UNTIL LATE SUN AND SUN EVENING. ALSO RAISED INLAND MAX
TEMPS 2-3 DEGREES. PATTERN RECOGNITION WOULD SUGGEST THERE COULD BE
NOCTURNAL THUNDERSTORMS SUN NIGHT...BUT MODEL SOUNDINGS DO NOT
SUPPORT CONVECTION ANYWHERE WEST OF THE CASCADES. WEISHAAR

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THE FIRST AND STRONGEST
UPPER LEVEL TROUGH WILL SLIDE N-NE INTO THE REGION LATE SUNDAY AND
CONTINUE TO ENHANCE SHOWER CHANCES THROUGH THE EARLY PART OF NEXT
WEEK. THE ASSOCIATED FRONT WILL CROSS THE REGION OVERNIGHT PROVIDING
FOR MUCH COOLER HIGH TEMPS ON MONDAY GIVEN THE ABUNDANT CLOUD COVER
AND MODELS SUGGESTING H8 TEMPS DECREASING AROUND 10 DEG C BY MONDAY
MORNING. WHILE MODELS SUGGEST SOME INSTABILITY...PARTICULARLY
TUESDAY AS THE COLD CORE ALOFT MOVES ACROSS THE AREA...THINK MUCH
COOLER SURFACE TEMPERATURES WILL LARGELY LIMIT THUNDER CHANCES.
HOWEVER...THE TIMING OF SHORTWAVE IMPULSES MAY ENHANCE THIS
POTENTIAL AT TIMES BUT CONFIDENCE IN THIS SCENARIO REMAINS LOW
ENOUGH TO EXCLUDE ANY THUNDERSTORMS IN THE EXTENDED PERIOD FOR NOW
WITH THE EXCEPTION OF MAINTAINING A CHANCE FOR MONDAY LATE
AFTERNOON/EVENING IN THE CASCADES SOUTH OF AROUND MT HOOD.
TEMPERATURES LIKELY REBOUND A LITTLE...CLOSER TO SEASONAL
NORMS...FOR THE SECOND HALF OF THE WEEK AS SHOWERS END AND WEAK
SHORTWAVE RIDGING PROVIDING FOR SOME AFTERNOON SUN AFTER MORNING
CLOUDS.  CULLEN
&&

.AVIATION...HIGH CLOUDS CONTINUE ACROSS THE AREA UNDER DRY SW
FLOW ALOFT. IFR STRATUS WILL PERSIST ALONG THE COAST. MARINE
STRATUS ALONG THE COLUMBIA RIVER REACHED KKLS THIS MORNING...BUT
WILL GRADUALLY BURN OFF BY 17Z-19Z THIS MORNING. WILL ALSO HAVE
PATCHY LOW CLOUDS FROM KSLE THROUGH KEUG TO K61S...AND IN
CASCADES TIL 17Z.

KPDX AND APPROACHES...VFR UNDER VARIABLE HIGH CLOUDS. ROCKEY/27

&&

.MARINE...BENIGN CONDITIONS CONTINUE INTO NEXT WEEK...WITH W TO NW
WINDS 15 KT OR LESS AND SEAS RUNNING 4 TO 6 FT. ROCKEY.

&&

.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 290900 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
159 AM PDT FRI MAY 29 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. MEANWHILE...A CLOSED UPPER LEVEL LOW WILL MOVE INTO
BRITISH COLUMBIA. DESPITE WEST FLOW ALOFT...THERE WILL BE ENOUGH
RESIDUAL INSTABILITY OVER THE HIGHER CASCADES TODAY FOR A CONTINUED
THREAT OF LATE-DAY THUNDERSTORMS. THE UPPER RIDGE STARTS TO FLATTEN
TODAY...BUT IS EXPECTED TO STRENGTHEN A LITTLE SATURDAY. ANY
THUNDERSTORM THREAT SATURDAY SHOULD BE CONFINED TO THE SOUTHERN LANE
COUNTY CASCADES. THE NEXT UPPER LOW SWINGS  TOWARD THE OREGON COAST
SUNDAY...RESULTING IN A LITTLE MORE COOLING BUT A BETTER CHANCE OF
CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE LAYER IS EXPECTED OVER
THE AREA EARLY NEXT WEEK.

&&
.SHORT TERM...TODAY THROUGH SUNDAY...THE LARGE-SCALE PATTERN REMAINS
VIRTUALLY UNCHANGED FROM 24 HOURS AGO. WATER VAPOR LOOP SHOWS 500 MB
HIGH PRES RIDGE AXIS EXTENDING FROM 30N 125W TO A 577 DM HIGH CENTER
NEAR 50N 140W. ALSO OF NOTE IS A CLOSED UPPER LOW ALONG THE CENTRAL
BRITISH COLUMBIA COAST AND ANOTHER ONE OUT AROUND 40N 150W. THIS
LATTER LOW IS THE ONE THAT WILL BECOME A PLAYER FOR OUR WEATHER LATE
IN THE WEEKEND.

TODAY LOOKS TO BE A NEAR REPEAT OF YESTERDAY. THE MARINE LAYER HAS
NOT CHANGED ALL THAT MUCH. KKLS REPORTED OVC CONDITIONS AROUND
07Z...SIMILAR TO 24 HOURS AGO. THE NAM AND HI-RES ARW SUGGEST MARINE
STRATUS WILL COME DOWN THE COLUMBIA RIVER AND FILL IN WRN CLARK
COUNTY IN SW WA BY 12Z. THE KAST-KDPX GRADIENT IS SLIGHTLY STRONGER
AT 08Z...2.1 MB...COMPARED TO 08Z THU. THIS IS LIKELY DUE TO THE
WARMER INTERIOR RESULTING IN SLIGHTLY LOWER SFC PRES. MODEL FORECAST
850 MB TEMPS ARE SIMILAR TO THU...MAYBE UP A DEGREE INLAND.
THUS...HAVE NUDGED MAX TEMPS UP A DEGREE OR TWO...BASED ON THU
VALUES. TODAY IS LIKELY TO BE THE WARMEST DAY OF 2015 AT KPDX...IF WE
HIT THE FCST HIGH OF 85.

THE FORECAST PROBLEM CONTINUES TO BE THE THUNDERSTORM THREAT FOR THE
CASCADES. MODELS DID A PRETTY GOOD JOB PIN-POINTING THE CONVECTIVE
THREAT FOR THU...ALONG THE CASCADE CREST. 06Z MODEL SOUNDINGS FOR A
POINT NEAR SANTIAM PASS CONTINUE TO SHOW FAIRLY ROBUST CONVECTIVE
PARAMETERS LATE THIS AFTERNOON. NAM SOUNDING GIVES AN IMPRESSIVE 2800
J/KG SURFACE-BASED CAPE...WITH A ML CAPE NEAR 1450 J/KG. AGAIN...
BELIEVE THE NAM IS OVER-DOING THE SURFACE DEW POINTS. THE GFS
HAS A ML CAPE OF 500 J/KG. GFS 700 MB THETA E RIDGE IS CENTERED ALONG
THE OREGON CASCADE CREST 00Z SAT. A LITTLE LOWER THETA E VALUES IN
THE S WA CASCADES COMPARED TO THU. DECIDED TO EXPAND THE THUNDERSTORM
THREAT JUST A BIT MORE W...BUT STILL KEEPING IT IN THE HIGHER
CASCADES AND NOT THE FOOTHILLS.

FOR SAT THE 500 MB HEIGHTS RISE JUST A BIT AS THE UPPER LOW IN THE
CENTRAL PAC GRADUALLY MIGRATES EAST. THE MAIN IMPACT WILL BE A MORE
STABLE AIR MASS WITH DEEPER WLY FLOW ALOFT. GFS STILL INDICATES SOME
INSTABILITY OVER THE SRN LANE COUNTY CASCADES SAT AFTERNOON AND HAVE
LEFT THE MENTION OF THUNDERSTORMS FOR THAT AREA. MAV AND MET GUIDANCE
INDICATE 2-3 DEGREES COOLING SAT...BUT NOT SURE TO BELIEVE THAT.
MODEL FORECAST 850 MB TEMPS EASE ABOUT A DEGREE...BUT WITH A SLIGHTLY
WARMER START AM EXPECTING MAX TEMPS TO BE CLOSE TO FRI VALUES.

THE FLOW ALOFT BACKS TO THE SW LATE SAT AND SAT NIGHT. THE 500 MB
RIDGE AXIS IS EXPECTED TO BE CENTERED OVER THE FORECAST AREA SAT
NIGHT...THEN SLOWLY SHIFT EAST SUN. NAM CROSS-SECTION FROM KAST
THROUGH THE GORGE SHOWS INCREASING MID AND HIGH LEVEL MOISTURE SUN
AFTERNOON. REDUCED POPS SUN AS MODELS NOT SHOWING DEEPER MOISTURE
DEVELOPING UNTIL LATE SUN AND SUN EVENING. ALSO RAISED INLAND MAX
TEMPS 2-3 DEGREES. PATTERN RECOGNITION WOULD SUGGEST THERE COULD BE
NOCTURNAL THUNDERSTORMS SUN NIGHT...BUT MODEL SOUNDINGS DO NOT
SUPPORT CONVECTION ANYWHERE WEST OF THE CASCADES. WEISHAAR

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THE FIRST AND STRONGEST
UPPER LEVEL TROUGH WILL SLIDE N-NE INTO THE REGION LATE SUNDAY AND
CONTINUE TO ENHANCE SHOWER CHANCES THROUGH THE EARLY PART OF NEXT
WEEK. THE ASSOCIATED FRONT WILL CROSS THE REGION OVERNIGHT PROVIDING
FOR MUCH COOLER HIGH TEMPS ON MONDAY GIVEN THE ABUNDANT CLOUD COVER
AND MODELS SUGGESTING H8 TEMPS DECREASING AROUND 10 DEG C BY MONDAY
MORNING. WHILE MODELS SUGGEST SOME INSTABILITY...PARTICULARLY
TUESDAY AS THE COLD CORE ALOFT MOVES ACROSS THE AREA...THINK MUCH
COOLER SURFACE TEMPERATURES WILL LARGELY LIMIT THUNDER CHANCES.
HOWEVER...THE TIMING OF SHORTWAVE IMPULSES MAY ENHANCE THIS
POTENTIAL AT TIMES BUT CONFIDENCE IN THIS SCENARIO REMAINS LOW
ENOUGH TO EXCLUDE ANY THUNDERSTORMS IN THE EXTENDED PERIOD FOR NOW
WITH THE EXCEPTION OF MAINTAINING A CHANCE FOR MONDAY LATE
AFTERNOON/EVENING IN THE CASCADES SOUTH OF AROUND MT HOOD.
TEMPERATURES LIKELY REBOUND A LITTLE...CLOSER TO SEASONAL
NORMS...FOR THE SECOND HALF OF THE WEEK AS SHOWERS END AND WEAK
SHORTWAVE RIDGING PROVIDING FOR SOME AFTERNOON SUN AFTER MORNING
CLOUDS.  CULLEN
&&

.AVIATION...DRY SW FLOW ALOFT...WITH VARIABLE HIGH CLOUDS OVER
THE REGION TODAY. IFR STRATUS WILL PERSIST ALONG THE COAST. LIKE
ON THU AM... WILL HAVE AREAS OF STRATUS ALONG THE COLUMBIA RIVER
UPSTREAM TO KPDX/KTTD THIS AM. ALSO...WILL HAVE PATCHY FOG OR LOW
CLOUDS FROM KSLE THROUGH KEUG TO K61S...AND IN CASCADES TIL 17Z.

KPDX AND APPROACHES...VFR UNDER VARIABLE HIGH CLOUDS. WILL HAVE
IFR STRATUS ARRIVING FROM THE N BETWEEN 12Z AND 13Z THIS AM. LIKE
ON THU AM...THIS STRATUS WILL BURN OUT 16Z TO 17Z.   ROCKEY.
&&

.MARINE...BENIGN CONDITIONS CONTINUE INTO NEXT WEEK...WITH W TO NW
WINDS 15 KT OR LESS AND SEAS RUNNING 4 TO 6 FT. ROCKEY.
&&

.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 290900 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
159 AM PDT FRI MAY 29 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. MEANWHILE...A CLOSED UPPER LEVEL LOW WILL MOVE INTO
BRITISH COLUMBIA. DESPITE WEST FLOW ALOFT...THERE WILL BE ENOUGH
RESIDUAL INSTABILITY OVER THE HIGHER CASCADES TODAY FOR A CONTINUED
THREAT OF LATE-DAY THUNDERSTORMS. THE UPPER RIDGE STARTS TO FLATTEN
TODAY...BUT IS EXPECTED TO STRENGTHEN A LITTLE SATURDAY. ANY
THUNDERSTORM THREAT SATURDAY SHOULD BE CONFINED TO THE SOUTHERN LANE
COUNTY CASCADES. THE NEXT UPPER LOW SWINGS  TOWARD THE OREGON COAST
SUNDAY...RESULTING IN A LITTLE MORE COOLING BUT A BETTER CHANCE OF
CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE LAYER IS EXPECTED OVER
THE AREA EARLY NEXT WEEK.

&&
.SHORT TERM...TODAY THROUGH SUNDAY...THE LARGE-SCALE PATTERN REMAINS
VIRTUALLY UNCHANGED FROM 24 HOURS AGO. WATER VAPOR LOOP SHOWS 500 MB
HIGH PRES RIDGE AXIS EXTENDING FROM 30N 125W TO A 577 DM HIGH CENTER
NEAR 50N 140W. ALSO OF NOTE IS A CLOSED UPPER LOW ALONG THE CENTRAL
BRITISH COLUMBIA COAST AND ANOTHER ONE OUT AROUND 40N 150W. THIS
LATTER LOW IS THE ONE THAT WILL BECOME A PLAYER FOR OUR WEATHER LATE
IN THE WEEKEND.

TODAY LOOKS TO BE A NEAR REPEAT OF YESTERDAY. THE MARINE LAYER HAS
NOT CHANGED ALL THAT MUCH. KKLS REPORTED OVC CONDITIONS AROUND
07Z...SIMILAR TO 24 HOURS AGO. THE NAM AND HI-RES ARW SUGGEST MARINE
STRATUS WILL COME DOWN THE COLUMBIA RIVER AND FILL IN WRN CLARK
COUNTY IN SW WA BY 12Z. THE KAST-KDPX GRADIENT IS SLIGHTLY STRONGER
AT 08Z...2.1 MB...COMPARED TO 08Z THU. THIS IS LIKELY DUE TO THE
WARMER INTERIOR RESULTING IN SLIGHTLY LOWER SFC PRES. MODEL FORECAST
850 MB TEMPS ARE SIMILAR TO THU...MAYBE UP A DEGREE INLAND.
THUS...HAVE NUDGED MAX TEMPS UP A DEGREE OR TWO...BASED ON THU
VALUES. TODAY IS LIKELY TO BE THE WARMEST DAY OF 2015 AT KPDX...IF WE
HIT THE FCST HIGH OF 85.

THE FORECAST PROBLEM CONTINUES TO BE THE THUNDERSTORM THREAT FOR THE
CASCADES. MODELS DID A PRETTY GOOD JOB PIN-POINTING THE CONVECTIVE
THREAT FOR THU...ALONG THE CASCADE CREST. 06Z MODEL SOUNDINGS FOR A
POINT NEAR SANTIAM PASS CONTINUE TO SHOW FAIRLY ROBUST CONVECTIVE
PARAMETERS LATE THIS AFTERNOON. NAM SOUNDING GIVES AN IMPRESSIVE 2800
J/KG SURFACE-BASED CAPE...WITH A ML CAPE NEAR 1450 J/KG. AGAIN...
BELIEVE THE NAM IS OVER-DOING THE SURFACE DEW POINTS. THE GFS
HAS A ML CAPE OF 500 J/KG. GFS 700 MB THETA E RIDGE IS CENTERED ALONG
THE OREGON CASCADE CREST 00Z SAT. A LITTLE LOWER THETA E VALUES IN
THE S WA CASCADES COMPARED TO THU. DECIDED TO EXPAND THE THUNDERSTORM
THREAT JUST A BIT MORE W...BUT STILL KEEPING IT IN THE HIGHER
CASCADES AND NOT THE FOOTHILLS.

FOR SAT THE 500 MB HEIGHTS RISE JUST A BIT AS THE UPPER LOW IN THE
CENTRAL PAC GRADUALLY MIGRATES EAST. THE MAIN IMPACT WILL BE A MORE
STABLE AIR MASS WITH DEEPER WLY FLOW ALOFT. GFS STILL INDICATES SOME
INSTABILITY OVER THE SRN LANE COUNTY CASCADES SAT AFTERNOON AND HAVE
LEFT THE MENTION OF THUNDERSTORMS FOR THAT AREA. MAV AND MET GUIDANCE
INDICATE 2-3 DEGREES COOLING SAT...BUT NOT SURE TO BELIEVE THAT.
MODEL FORECAST 850 MB TEMPS EASE ABOUT A DEGREE...BUT WITH A SLIGHTLY
WARMER START AM EXPECTING MAX TEMPS TO BE CLOSE TO FRI VALUES.

THE FLOW ALOFT BACKS TO THE SW LATE SAT AND SAT NIGHT. THE 500 MB
RIDGE AXIS IS EXPECTED TO BE CENTERED OVER THE FORECAST AREA SAT
NIGHT...THEN SLOWLY SHIFT EAST SUN. NAM CROSS-SECTION FROM KAST
THROUGH THE GORGE SHOWS INCREASING MID AND HIGH LEVEL MOISTURE SUN
AFTERNOON. REDUCED POPS SUN AS MODELS NOT SHOWING DEEPER MOISTURE
DEVELOPING UNTIL LATE SUN AND SUN EVENING. ALSO RAISED INLAND MAX
TEMPS 2-3 DEGREES. PATTERN RECOGNITION WOULD SUGGEST THERE COULD BE
NOCTURNAL THUNDERSTORMS SUN NIGHT...BUT MODEL SOUNDINGS DO NOT
SUPPORT CONVECTION ANYWHERE WEST OF THE CASCADES. WEISHAAR

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THE FIRST AND STRONGEST
UPPER LEVEL TROUGH WILL SLIDE N-NE INTO THE REGION LATE SUNDAY AND
CONTINUE TO ENHANCE SHOWER CHANCES THROUGH THE EARLY PART OF NEXT
WEEK. THE ASSOCIATED FRONT WILL CROSS THE REGION OVERNIGHT PROVIDING
FOR MUCH COOLER HIGH TEMPS ON MONDAY GIVEN THE ABUNDANT CLOUD COVER
AND MODELS SUGGESTING H8 TEMPS DECREASING AROUND 10 DEG C BY MONDAY
MORNING. WHILE MODELS SUGGEST SOME INSTABILITY...PARTICULARLY
TUESDAY AS THE COLD CORE ALOFT MOVES ACROSS THE AREA...THINK MUCH
COOLER SURFACE TEMPERATURES WILL LARGELY LIMIT THUNDER CHANCES.
HOWEVER...THE TIMING OF SHORTWAVE IMPULSES MAY ENHANCE THIS
POTENTIAL AT TIMES BUT CONFIDENCE IN THIS SCENARIO REMAINS LOW
ENOUGH TO EXCLUDE ANY THUNDERSTORMS IN THE EXTENDED PERIOD FOR NOW
WITH THE EXCEPTION OF MAINTAINING A CHANCE FOR MONDAY LATE
AFTERNOON/EVENING IN THE CASCADES SOUTH OF AROUND MT HOOD.
TEMPERATURES LIKELY REBOUND A LITTLE...CLOSER TO SEASONAL
NORMS...FOR THE SECOND HALF OF THE WEEK AS SHOWERS END AND WEAK
SHORTWAVE RIDGING PROVIDING FOR SOME AFTERNOON SUN AFTER MORNING
CLOUDS.  CULLEN
&&

.AVIATION...DRY SW FLOW ALOFT...WITH VARIABLE HIGH CLOUDS OVER
THE REGION TODAY. IFR STRATUS WILL PERSIST ALONG THE COAST. LIKE
ON THU AM... WILL HAVE AREAS OF STRATUS ALONG THE COLUMBIA RIVER
UPSTREAM TO KPDX/KTTD THIS AM. ALSO...WILL HAVE PATCHY FOG OR LOW
CLOUDS FROM KSLE THROUGH KEUG TO K61S...AND IN CASCADES TIL 17Z.

KPDX AND APPROACHES...VFR UNDER VARIABLE HIGH CLOUDS. WILL HAVE
IFR STRATUS ARRIVING FROM THE N BETWEEN 12Z AND 13Z THIS AM. LIKE
ON THU AM...THIS STRATUS WILL BURN OUT 16Z TO 17Z.   ROCKEY.
&&

.MARINE...BENIGN CONDITIONS CONTINUE INTO NEXT WEEK...WITH W TO NW
WINDS 15 KT OR LESS AND SEAS RUNNING 4 TO 6 FT. ROCKEY.
&&

.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 290351 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
846 PM PDT THU MAY 28 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. MEANWHILE A CLOSED UPPER LEVEL LOW WILL MOVE INTO
BRITISH COLUMBIA. WARMER THAN AVERAGE WEATHER WILL LAST THROUGH AT
LEAST SATURDAY...WITH HIGH TEMPERATURES MOST LIKELY PEAKING ON
FRIDAY. THE UPPER RIDGE STARTS TO FLATTEN FRI AND SAT. THE HIGHER
CASCADES WILL CONTINUE TO HAVE A SLIM THREAT OF LATE-DAY
THUNDERSTORMS THE NEXT COUPLE OF DAYS. THE NEXT UPPER LOW SWINGS
TOWARD THE OREGON COAST SUNDAY...RESULTING IN A LITTLE MORE COOLING
BUT A BETTER CHANCE OF CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE
LAYER IS EXPECTED OVER THE AREA EARLY NEXT WEEK.

&&

.UPDATE...A FEW THUNDERSTORMS DEVELOPED ALONG THE CASCADE CREST THIS
AFTERNOON BETWEEN SANTIAM PASS AND TIMOTHY LAKE.  SOME LIKELY
CONTAINED SMALL HAIL BUT WITH LITTLE MOVEMENT TO THE STORM CELLS
THERE WAS LIKELY A GOOD DRENCHING UNDER THEM. OTHERWISE FAIR
CONDITIONS ACROSS THE AREA EXCEPT FOR THE COAST WHERE SHALLOW MARINE
STRATUS CONTINUES.  AGAIN SOME OF THE STATUS WILL WORK INTO GAPS IN
THE COASTAL TERRAIN AND UP THE LOWER COLUMBIA RIVER TO THE PORTLAND
AREA.  MODELS SUGGEST ANOTHER ROUND OF CONVECTION OVER THE CASCADES
FRI AFTERNOON BUT LOOKS TO BE MORE FOCUSED OVER THE LANE COUNTY
CASCADES.    TEMPERATURES INLAND WILL BE AROUND 10 DEGREES ABOVE
NORMAL NEXT COUPLE OF DAYS. HOWEVER COASTAL AREAS WILL REMAIN UNDER
STRONG MARINE INFLUENCE SO TEMPS WILL BE AT OR BELOW NORMAL.

PREVIOUS DISCUSSION FOLLOWS...
SHORT TERM...TONIGHT THROUGH SUNDAY...AN UPPER LEVEL RIDGE IS
BUILDING OVER THE PAC NW TODAY. THIS RIDGE WILL BRING WARM AND DRY
WEATHER TO THE PAC NW THROUGH SAT. A CLOSED LOW WILL MOVE INTO B.C.
OVER THE NEXT COUPLE OF DAYS...WHICH WILL ACT TO FLATTEN THE RIDGE A
BIT...BUT OTHERWISE HAVE LITTLE IMPACT ON OUR SENSIBLE WEATHER.

WARM AND DRY WEATHER IS IN CONTROL TODAY WITH PLENTY OF SUNSHINE
ACROSS MOST OF THE REGION. THE EXCEPTION IS AT THE COAST...WHERE
MARINE CLOUDS AND A COOLING NW BREEZE ARE KEEPING TEMPS IN THE 50S
AND 60S. TEMPERATURES ARE STEADILY CLIMBING OVER THE INTERIOR...WITH
CURRENT OBSERVED TEMPS IN THE UPPER 70S AND LOW 80S FOR MOST OF THE
LOWLANDS. EXPECT HIGHS TO TOP OUT IN THE LOW TO MID 80S LATER THIS
AFTERNOON. VISIBLE SATELLITE IMAGERY HAS SHOWN CUMULUS BUILDING ALONG
THE CASCADE CREST SINCE AROUND MIDDAY. THERE IS A SLIGHT CHANCE THAT
A FEW OF THE CUMULUS BUILDUPS MAY DEVELOP INTO THUNDERSHOWERS DURING
THE LATE AFTERNOON AND EARLY EVENING.

FRI LOOKS TO BE VERY SIMILAR TO TODAY. EXPECT A WEAK MARINE PUSH
OVERNIGHT...WITH CLOUDS ONLY ABLE TO PUSH INTO THE COAST RANGE GAPS
AND A LITTLE WAY UP THE COLUMBIA RIVER...LEAVING MOST OF THE INTERIOR
CLOUD FREE. FRI LOOKS TO BE THE WARMEST DAY OF THE STRETCH WITH
AFTERNOON HIGHS A DEGREE OR TWO WARMER THAN TODAY. A SLIGHT THREAT OF
LATE AFTERNOON/EARLY EVENING THUNDERSTORMS ALONG THE CASCADE CREST
WILL CONTINUE AS WELL.

THE UPPER RIDGE AXIS REMAINS OVER US FOR ONE LAST DAY ON SAT. EXPECT
IT WILL STILL BE WARM...BUT IT APPEARS THAT HIGH CLOUDS WILL BE
ARRIVING DURING THE DAY AHEAD OF THE NEXT APPROACHING UPPER LEVEL
LOW. ALTHOUGH 850 MB TEMPS ARE SIMILAR TO TODAY AND FRI...EXPECT
THESE CLOUDS MAY KNOCK SURFACE TEMPS DOWN A FEW DEGREES. THE FLOW
ALOFT WILL BEGIN TO TURN SOUTHWESTERLY. THERE MAY AGAIN BE A FEW
SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON...WITH THE MAIN THREAT
REMAINING ALONG THE LANE COUNTY CASCADE CREST.

UPPER LEVEL LOW PRES WILL APPROACH THE COAST FROM THE SW ON SUN. THIS
WILL BRING A FURTHER INCREASE IN CLOUD COVER AND COOL TEMPS A LITTLE
MORE. THE FCST MODELS ALSO INDICATE A BETTER CHANCE OF AFTERNOON
THUNDERSTORMS IN THE CASCADES AS THE UPPER LEVEL FLOW TURNS
SOUTHERLY. PYLE

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THE FIRST AND STRONGEST
UPPER LEVEL TROUGH WILL SLIDE N-NE INTO THE REGION LATE SUNDAY AND
CONTINUE TO ENHANCE SHOWER CHANCES THROUGH THE EARLY PART OF NEXT
WEEK. THE ASSOCIATED FRONT WILL CROSS THE REGION OVERNIGHT PROVIDING
FOR MUCH COOLER HIGH TEMPS ON MONDAY GIVEN THE ABUNDANT CLOUD COVER
AND MODELS SUGGESTING H8 TEMPS DECREASING AROUND 10 DEG C BY MONDAY
MORNING. WHILE MODELS SUGGEST SOME INSTABILITY...PARTICULARLY
TUESDAY AS THE COLD CORE ALOFT MOVES ACROSS THE AREA...THINK MUCH
COOLER SURFACE TEMPERATURES WILL LARGELY LIMIT THUNDER CHANCES.
HOWEVER...THE TIMING OF SHORTWAVE IMPULSES MAY ENHANCE THIS
POTENTIAL AT TIMES BUT CONFIDENCE IN THIS SCENARIO REMAINS LOW
ENOUGH TO EXCLUDE ANY THUNDERSTORMS IN THE EXTENDED PERIOD FOR NOW
WITH THE EXCEPTION OF MAINTAINING A CHANCE FOR MONDAY LATE
AFTERNOON/EVENING IN THE CASCADES SOUTH OF AROUND MT HOOD.
TEMPERATURES LIKELY REBOUND A LITTLE...CLOSER TO SEASONAL
NORMS...FOR THE SECOND HALF OF THE WEEK AS SHOWERS END AND WEAK
SHORTWAVE RIDGING PROVIDING FOR SOME AFTERNOON SUN AFTER MORNING
CLOUDS.  CULLEN
&&

.AVIATION...VFR CONDITIONS CONTINUE INLAND UNDER DRY
NORTHWESTERLY FLOW ALOFT. MVFR STRATUS POSSIBLE BETWEEN AFTER 12Z.
MARINE STRATUS ALONG THE COAST CONTINUES WITH IFR CIGS. PATCHY IFR
VSBY POSSIBLE AFTER 09Z. INLAND CONDITIONS IMPROVE TO VFR BY 18Z
FRIDAY BUT COASTAL SITES WILL LIKELY REMAIN IFR OR POSSIBLY RISE
TO MVFR.

KPDX AND APPROACHES...MVFR STRATUS POSSIBLE BETWEEN 12-18Z.
OTHERWISE VFR. BOWEN/64

&&

.MARINE...BENIGN CONDITIONS CONTINUE THROUGH THE FORECAST PERIOD.
WINDS WILL REMAIN BELOW 20 KT. MIXED SEAS AROUND 4 TO 6 FT WILL
CONTINUE THROUGH MUCH OF NEXT WEEK...WITH SWELL TRAINS OUT OF THE
W AND SW. BOWEN/64

&&

.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 290351 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
846 PM PDT THU MAY 28 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. MEANWHILE A CLOSED UPPER LEVEL LOW WILL MOVE INTO
BRITISH COLUMBIA. WARMER THAN AVERAGE WEATHER WILL LAST THROUGH AT
LEAST SATURDAY...WITH HIGH TEMPERATURES MOST LIKELY PEAKING ON
FRIDAY. THE UPPER RIDGE STARTS TO FLATTEN FRI AND SAT. THE HIGHER
CASCADES WILL CONTINUE TO HAVE A SLIM THREAT OF LATE-DAY
THUNDERSTORMS THE NEXT COUPLE OF DAYS. THE NEXT UPPER LOW SWINGS
TOWARD THE OREGON COAST SUNDAY...RESULTING IN A LITTLE MORE COOLING
BUT A BETTER CHANCE OF CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE
LAYER IS EXPECTED OVER THE AREA EARLY NEXT WEEK.

&&

.UPDATE...A FEW THUNDERSTORMS DEVELOPED ALONG THE CASCADE CREST THIS
AFTERNOON BETWEEN SANTIAM PASS AND TIMOTHY LAKE.  SOME LIKELY
CONTAINED SMALL HAIL BUT WITH LITTLE MOVEMENT TO THE STORM CELLS
THERE WAS LIKELY A GOOD DRENCHING UNDER THEM. OTHERWISE FAIR
CONDITIONS ACROSS THE AREA EXCEPT FOR THE COAST WHERE SHALLOW MARINE
STRATUS CONTINUES.  AGAIN SOME OF THE STATUS WILL WORK INTO GAPS IN
THE COASTAL TERRAIN AND UP THE LOWER COLUMBIA RIVER TO THE PORTLAND
AREA.  MODELS SUGGEST ANOTHER ROUND OF CONVECTION OVER THE CASCADES
FRI AFTERNOON BUT LOOKS TO BE MORE FOCUSED OVER THE LANE COUNTY
CASCADES.    TEMPERATURES INLAND WILL BE AROUND 10 DEGREES ABOVE
NORMAL NEXT COUPLE OF DAYS. HOWEVER COASTAL AREAS WILL REMAIN UNDER
STRONG MARINE INFLUENCE SO TEMPS WILL BE AT OR BELOW NORMAL.

PREVIOUS DISCUSSION FOLLOWS...
SHORT TERM...TONIGHT THROUGH SUNDAY...AN UPPER LEVEL RIDGE IS
BUILDING OVER THE PAC NW TODAY. THIS RIDGE WILL BRING WARM AND DRY
WEATHER TO THE PAC NW THROUGH SAT. A CLOSED LOW WILL MOVE INTO B.C.
OVER THE NEXT COUPLE OF DAYS...WHICH WILL ACT TO FLATTEN THE RIDGE A
BIT...BUT OTHERWISE HAVE LITTLE IMPACT ON OUR SENSIBLE WEATHER.

WARM AND DRY WEATHER IS IN CONTROL TODAY WITH PLENTY OF SUNSHINE
ACROSS MOST OF THE REGION. THE EXCEPTION IS AT THE COAST...WHERE
MARINE CLOUDS AND A COOLING NW BREEZE ARE KEEPING TEMPS IN THE 50S
AND 60S. TEMPERATURES ARE STEADILY CLIMBING OVER THE INTERIOR...WITH
CURRENT OBSERVED TEMPS IN THE UPPER 70S AND LOW 80S FOR MOST OF THE
LOWLANDS. EXPECT HIGHS TO TOP OUT IN THE LOW TO MID 80S LATER THIS
AFTERNOON. VISIBLE SATELLITE IMAGERY HAS SHOWN CUMULUS BUILDING ALONG
THE CASCADE CREST SINCE AROUND MIDDAY. THERE IS A SLIGHT CHANCE THAT
A FEW OF THE CUMULUS BUILDUPS MAY DEVELOP INTO THUNDERSHOWERS DURING
THE LATE AFTERNOON AND EARLY EVENING.

FRI LOOKS TO BE VERY SIMILAR TO TODAY. EXPECT A WEAK MARINE PUSH
OVERNIGHT...WITH CLOUDS ONLY ABLE TO PUSH INTO THE COAST RANGE GAPS
AND A LITTLE WAY UP THE COLUMBIA RIVER...LEAVING MOST OF THE INTERIOR
CLOUD FREE. FRI LOOKS TO BE THE WARMEST DAY OF THE STRETCH WITH
AFTERNOON HIGHS A DEGREE OR TWO WARMER THAN TODAY. A SLIGHT THREAT OF
LATE AFTERNOON/EARLY EVENING THUNDERSTORMS ALONG THE CASCADE CREST
WILL CONTINUE AS WELL.

THE UPPER RIDGE AXIS REMAINS OVER US FOR ONE LAST DAY ON SAT. EXPECT
IT WILL STILL BE WARM...BUT IT APPEARS THAT HIGH CLOUDS WILL BE
ARRIVING DURING THE DAY AHEAD OF THE NEXT APPROACHING UPPER LEVEL
LOW. ALTHOUGH 850 MB TEMPS ARE SIMILAR TO TODAY AND FRI...EXPECT
THESE CLOUDS MAY KNOCK SURFACE TEMPS DOWN A FEW DEGREES. THE FLOW
ALOFT WILL BEGIN TO TURN SOUTHWESTERLY. THERE MAY AGAIN BE A FEW
SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON...WITH THE MAIN THREAT
REMAINING ALONG THE LANE COUNTY CASCADE CREST.

UPPER LEVEL LOW PRES WILL APPROACH THE COAST FROM THE SW ON SUN. THIS
WILL BRING A FURTHER INCREASE IN CLOUD COVER AND COOL TEMPS A LITTLE
MORE. THE FCST MODELS ALSO INDICATE A BETTER CHANCE OF AFTERNOON
THUNDERSTORMS IN THE CASCADES AS THE UPPER LEVEL FLOW TURNS
SOUTHERLY. PYLE

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THE FIRST AND STRONGEST
UPPER LEVEL TROUGH WILL SLIDE N-NE INTO THE REGION LATE SUNDAY AND
CONTINUE TO ENHANCE SHOWER CHANCES THROUGH THE EARLY PART OF NEXT
WEEK. THE ASSOCIATED FRONT WILL CROSS THE REGION OVERNIGHT PROVIDING
FOR MUCH COOLER HIGH TEMPS ON MONDAY GIVEN THE ABUNDANT CLOUD COVER
AND MODELS SUGGESTING H8 TEMPS DECREASING AROUND 10 DEG C BY MONDAY
MORNING. WHILE MODELS SUGGEST SOME INSTABILITY...PARTICULARLY
TUESDAY AS THE COLD CORE ALOFT MOVES ACROSS THE AREA...THINK MUCH
COOLER SURFACE TEMPERATURES WILL LARGELY LIMIT THUNDER CHANCES.
HOWEVER...THE TIMING OF SHORTWAVE IMPULSES MAY ENHANCE THIS
POTENTIAL AT TIMES BUT CONFIDENCE IN THIS SCENARIO REMAINS LOW
ENOUGH TO EXCLUDE ANY THUNDERSTORMS IN THE EXTENDED PERIOD FOR NOW
WITH THE EXCEPTION OF MAINTAINING A CHANCE FOR MONDAY LATE
AFTERNOON/EVENING IN THE CASCADES SOUTH OF AROUND MT HOOD.
TEMPERATURES LIKELY REBOUND A LITTLE...CLOSER TO SEASONAL
NORMS...FOR THE SECOND HALF OF THE WEEK AS SHOWERS END AND WEAK
SHORTWAVE RIDGING PROVIDING FOR SOME AFTERNOON SUN AFTER MORNING
CLOUDS.  CULLEN
&&

.AVIATION...VFR CONDITIONS CONTINUE INLAND UNDER DRY
NORTHWESTERLY FLOW ALOFT. MVFR STRATUS POSSIBLE BETWEEN AFTER 12Z.
MARINE STRATUS ALONG THE COAST CONTINUES WITH IFR CIGS. PATCHY IFR
VSBY POSSIBLE AFTER 09Z. INLAND CONDITIONS IMPROVE TO VFR BY 18Z
FRIDAY BUT COASTAL SITES WILL LIKELY REMAIN IFR OR POSSIBLY RISE
TO MVFR.

KPDX AND APPROACHES...MVFR STRATUS POSSIBLE BETWEEN 12-18Z.
OTHERWISE VFR. BOWEN/64

&&

.MARINE...BENIGN CONDITIONS CONTINUE THROUGH THE FORECAST PERIOD.
WINDS WILL REMAIN BELOW 20 KT. MIXED SEAS AROUND 4 TO 6 FT WILL
CONTINUE THROUGH MUCH OF NEXT WEEK...WITH SWELL TRAINS OUT OF THE
W AND SW. BOWEN/64

&&

.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 282201 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
301 PM PDT THU MAY 28 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. MEANWHILE A CLOSED UPPER LEVEL LOW WILL MOVE INTO
BRITISH COLUMBIA. WARMER THAN AVERAGE WEATHER WILL LAST THROUGH AT
LEAST SATURDAY...WITH HIGH TEMPERATURES MOST LIKELY PEAKING ON
FRIDAY. THE UPPER RIDGE STARTS TO FLATTEN FRI AND SAT. THE HIGHER
CASCADES WILL CONTINUE TO HAVE A SLIM THREAT OF LATE-DAY
THUNDERSTORMS THE NEXT COUPLE OF DAYS. THE NEXT UPPER LOW SWINGS
TOWARD THE OREGON COAST SUNDAY...RESULTING IN A LITTLE MORE COOLING
BUT A BETTER CHANCE OF CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE
LAYER IS EXPECTED OVER THE AREA EARLY NEXT WEEK.

&&

.SHORT TERM...TONIGHT THROUGH SUNDAY...AN UPPER LEVEL RIDGE IS
BUILDING OVER THE PAC NW TODAY. THIS RIDGE WILL BRING WARM AND DRY
WEATHER TO THE PAC NW THROUGH SAT. A CLOSED LOW WILL MOVE INTO B.C.
OVER THE NEXT COUPLE OF DAYS...WHICH WILL ACT TO FLATTEN THE RIDGE A
BIT...BUT OTHERWISE HAVE LITTLE IMPACT ON OUR SENSIBLE WEATHER.

WARM AND DRY WEATHER IS IN CONTROL TODAY WITH PLENTY OF SUNSHINE
ACROSS MOST OF THE REGION. THE EXCEPTION IS AT THE COAST...WHERE
MARINE CLOUDS AND A COOLING NW BREEZE ARE KEEPING TEMPS IN THE 50S
AND 60S. TEMPERATURES ARE STEADILY CLIMBING OVER THE INTERIOR...WITH
CURRENT OBSERVED TEMPS IN THE UPPER 70S AND LOW 80S FOR MOST OF THE
LOWLANDS. EXPECT HIGHS TO TOP OUT IN THE LOW TO MID 80S LATER THIS
AFTERNOON. VISIBLE SATELLITE IMAGERY HAS SHOWN CUMULUS BUILDING ALONG
THE CASCADE CREST SINCE AROUND MIDDAY. THERE IS A SLIGHT CHANCE THAT
A FEW OF THE CUMULUS BUILDUPS MAY DEVELOP INTO THUNDERSHOWERS DURING
THE LATE AFTERNOON AND EARLY EVENING.

FRI LOOKS TO BE VERY SIMILAR TO TODAY. EXPECT A WEAK MARINE PUSH
OVERNIGHT...WITH CLOUDS ONLY ABLE TO PUSH INTO THE COAST RANGE GAPS
AND A LITTLE WAY UP THE COLUMBIA RIVER...LEAVING MOST OF THE INTERIOR
CLOUD FREE. FRI LOOKS TO BE THE WARMEST DAY OF THE STRETCH WITH
AFTERNOON HIGHS A DEGREE OR TWO WARMER THAN TODAY. A SLIGHT THREAT OF
LATE AFTERNOON/EARLY EVENING THUNDERSTORMS ALONG THE CASCADE CREST
WILL CONTINUE AS WELL.

THE UPPER RIDGE AXIS REMAINS OVER US FOR ONE LAST DAY ON SAT. EXPECT
IT WILL STILL BE WARM...BUT IT APPEARS THAT HIGH CLOUDS WILL BE
ARRIVING DURING THE DAY AHEAD OF THE NEXT APPROACHING UPPER LEVEL
LOW. ALTHOUGH 850 MB TEMPS ARE SIMILAR TO TODAY AND FRI...EXPECT
THESE CLOUDS MAY KNOCK SURFACE TEMPS DOWN A FEW DEGREES. THE FLOW
ALOFT WILL BEGIN TO TURN SOUTHWESTERLY. THERE MAY AGAIN BE A FEW
SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON...WITH THE MAIN THREAT
REMAINING ALONG THE LANE COUNTY CASCADE CREST.

UPPER LEVEL LOW PRES WILL APPROACH THE COAST FROM THE SW ON SUN. THIS
WILL BRING A FURTHER INCREASE IN CLOUD COVER AND COOL TEMPS A LITTLE
MORE. THE FCST MODELS ALSO INDICATE A BETTER CHANCE OF AFTERNOON
THUNDERSTORMS IN THE CASCADES AS THE UPPER LEVEL FLOW TURNS
SOUTHERLY. PYLE

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THE FIRST AND STRONGEST
UPPER LEVEL TROUGH WILL SLIDE N-NE INTO THE REGION LATE SUNDAY AND
CONTINUE TO ENHANCE SHOWER CHANCES THROUGH THE EARLY PART OF NEXT
WEEK. THE ASSOCIATED FRONT WILL CROSS THE REGION OVERNIGHT PROVIDING
FOR MUCH COOLER HIGH TEMPS ON MONDAY GIVEN THE ABUNDANT CLOUD COVER
AND MODELS SUGGESTING H8 TEMPS DECREASING AROUND 10 DEG C BY MONDAY
MORNING. WHILE MODELS SUGGEST SOME INSTABILITY...PARTICULARLY
TUESDAY AS THE COLD CORE ALOFT MOVES ACROSS THE AREA...THINK MUCH
COOLER SURFACE TEMPERATURES WILL LARGELY LIMIT THUNDER CHANCES.
HOWEVER...THE TIMING OF SHORTWAVE IMPULSES MAY ENHANCE THIS
POTENTIAL AT TIMES BUT CONFIDENCE IN THIS SCENARIO REMAINS LOW
ENOUGH TO EXCLUDE ANY THUNDERSTORMS IN THE EXTENDED PERIOD FOR NOW
WITH THE EXCEPTION OF MAINTAINING A CHANCE FOR MONDAY LATE
AFTERNOON/EVENING IN THE CASCADES SOUTH OF AROUND MT HOOD.
TEMPERATURES LIKELY REBOUND A LITTLE...CLOSER TO SEASONAL
NORMS...FOR THE SECOND HALF OF THE WEEK AS SHOWERS END AND WEAK
SHORTWAVE RIDGING PROVIDING FOR SOME AFTERNOON SUN AFTER MORNING
CLOUDS.  CULLEN
&&

.AVIATION...VFR CONDITIONS CONTINUE UNDER DRY NORTHWESTERLY FLOW
ALOFT...WITH A SLIGHT CHANCE OF THUNDERSTORMS OVER THE CASCADES
THROUGH 04Z. MVFR STRATUS POSSIBLE BETWEEN 12-18Z ALONG THE
COLUMBIA RIVER. MARINE STRATUS ALONG THE COAST WILL BRING A
MIXTURE OF IFR/MVFR CIGS...WITH IFR VSBY POSSIBLE AFTER 09Z.

KPDX AND APPROACHES...VFR CONDITIONS CONTINUE THROUGH FRI.
THUNDERSTORMS POSSIBLE OVER THE CASCADES THROUGH 04Z. MVFR
STRATUS POSSIBLE BETWEEN 12-18Z. /64

&&

.MARINE...BENIGN CONDITIONS CONTINUE THROUGH THE FORECAST PERIOD.
WINDS WILL REMAIN GENERALLY BELOW SMALL CRAFT CRITERIA. MIXED SEAS
AROUND 4 TO 6 FT WILL CONTINUE THROUGH MUCH OF NEXT WEEK...WITH
SWELL TRAINS OUT OF THE W AND SW. /64

&&

.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 282201 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
301 PM PDT THU MAY 28 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. MEANWHILE A CLOSED UPPER LEVEL LOW WILL MOVE INTO
BRITISH COLUMBIA. WARMER THAN AVERAGE WEATHER WILL LAST THROUGH AT
LEAST SATURDAY...WITH HIGH TEMPERATURES MOST LIKELY PEAKING ON
FRIDAY. THE UPPER RIDGE STARTS TO FLATTEN FRI AND SAT. THE HIGHER
CASCADES WILL CONTINUE TO HAVE A SLIM THREAT OF LATE-DAY
THUNDERSTORMS THE NEXT COUPLE OF DAYS. THE NEXT UPPER LOW SWINGS
TOWARD THE OREGON COAST SUNDAY...RESULTING IN A LITTLE MORE COOLING
BUT A BETTER CHANCE OF CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE
LAYER IS EXPECTED OVER THE AREA EARLY NEXT WEEK.

&&

.SHORT TERM...TONIGHT THROUGH SUNDAY...AN UPPER LEVEL RIDGE IS
BUILDING OVER THE PAC NW TODAY. THIS RIDGE WILL BRING WARM AND DRY
WEATHER TO THE PAC NW THROUGH SAT. A CLOSED LOW WILL MOVE INTO B.C.
OVER THE NEXT COUPLE OF DAYS...WHICH WILL ACT TO FLATTEN THE RIDGE A
BIT...BUT OTHERWISE HAVE LITTLE IMPACT ON OUR SENSIBLE WEATHER.

WARM AND DRY WEATHER IS IN CONTROL TODAY WITH PLENTY OF SUNSHINE
ACROSS MOST OF THE REGION. THE EXCEPTION IS AT THE COAST...WHERE
MARINE CLOUDS AND A COOLING NW BREEZE ARE KEEPING TEMPS IN THE 50S
AND 60S. TEMPERATURES ARE STEADILY CLIMBING OVER THE INTERIOR...WITH
CURRENT OBSERVED TEMPS IN THE UPPER 70S AND LOW 80S FOR MOST OF THE
LOWLANDS. EXPECT HIGHS TO TOP OUT IN THE LOW TO MID 80S LATER THIS
AFTERNOON. VISIBLE SATELLITE IMAGERY HAS SHOWN CUMULUS BUILDING ALONG
THE CASCADE CREST SINCE AROUND MIDDAY. THERE IS A SLIGHT CHANCE THAT
A FEW OF THE CUMULUS BUILDUPS MAY DEVELOP INTO THUNDERSHOWERS DURING
THE LATE AFTERNOON AND EARLY EVENING.

FRI LOOKS TO BE VERY SIMILAR TO TODAY. EXPECT A WEAK MARINE PUSH
OVERNIGHT...WITH CLOUDS ONLY ABLE TO PUSH INTO THE COAST RANGE GAPS
AND A LITTLE WAY UP THE COLUMBIA RIVER...LEAVING MOST OF THE INTERIOR
CLOUD FREE. FRI LOOKS TO BE THE WARMEST DAY OF THE STRETCH WITH
AFTERNOON HIGHS A DEGREE OR TWO WARMER THAN TODAY. A SLIGHT THREAT OF
LATE AFTERNOON/EARLY EVENING THUNDERSTORMS ALONG THE CASCADE CREST
WILL CONTINUE AS WELL.

THE UPPER RIDGE AXIS REMAINS OVER US FOR ONE LAST DAY ON SAT. EXPECT
IT WILL STILL BE WARM...BUT IT APPEARS THAT HIGH CLOUDS WILL BE
ARRIVING DURING THE DAY AHEAD OF THE NEXT APPROACHING UPPER LEVEL
LOW. ALTHOUGH 850 MB TEMPS ARE SIMILAR TO TODAY AND FRI...EXPECT
THESE CLOUDS MAY KNOCK SURFACE TEMPS DOWN A FEW DEGREES. THE FLOW
ALOFT WILL BEGIN TO TURN SOUTHWESTERLY. THERE MAY AGAIN BE A FEW
SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON...WITH THE MAIN THREAT
REMAINING ALONG THE LANE COUNTY CASCADE CREST.

UPPER LEVEL LOW PRES WILL APPROACH THE COAST FROM THE SW ON SUN. THIS
WILL BRING A FURTHER INCREASE IN CLOUD COVER AND COOL TEMPS A LITTLE
MORE. THE FCST MODELS ALSO INDICATE A BETTER CHANCE OF AFTERNOON
THUNDERSTORMS IN THE CASCADES AS THE UPPER LEVEL FLOW TURNS
SOUTHERLY. PYLE

.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...THE FIRST AND STRONGEST
UPPER LEVEL TROUGH WILL SLIDE N-NE INTO THE REGION LATE SUNDAY AND
CONTINUE TO ENHANCE SHOWER CHANCES THROUGH THE EARLY PART OF NEXT
WEEK. THE ASSOCIATED FRONT WILL CROSS THE REGION OVERNIGHT PROVIDING
FOR MUCH COOLER HIGH TEMPS ON MONDAY GIVEN THE ABUNDANT CLOUD COVER
AND MODELS SUGGESTING H8 TEMPS DECREASING AROUND 10 DEG C BY MONDAY
MORNING. WHILE MODELS SUGGEST SOME INSTABILITY...PARTICULARLY
TUESDAY AS THE COLD CORE ALOFT MOVES ACROSS THE AREA...THINK MUCH
COOLER SURFACE TEMPERATURES WILL LARGELY LIMIT THUNDER CHANCES.
HOWEVER...THE TIMING OF SHORTWAVE IMPULSES MAY ENHANCE THIS
POTENTIAL AT TIMES BUT CONFIDENCE IN THIS SCENARIO REMAINS LOW
ENOUGH TO EXCLUDE ANY THUNDERSTORMS IN THE EXTENDED PERIOD FOR NOW
WITH THE EXCEPTION OF MAINTAINING A CHANCE FOR MONDAY LATE
AFTERNOON/EVENING IN THE CASCADES SOUTH OF AROUND MT HOOD.
TEMPERATURES LIKELY REBOUND A LITTLE...CLOSER TO SEASONAL
NORMS...FOR THE SECOND HALF OF THE WEEK AS SHOWERS END AND WEAK
SHORTWAVE RIDGING PROVIDING FOR SOME AFTERNOON SUN AFTER MORNING
CLOUDS.  CULLEN
&&

.AVIATION...VFR CONDITIONS CONTINUE UNDER DRY NORTHWESTERLY FLOW
ALOFT...WITH A SLIGHT CHANCE OF THUNDERSTORMS OVER THE CASCADES
THROUGH 04Z. MVFR STRATUS POSSIBLE BETWEEN 12-18Z ALONG THE
COLUMBIA RIVER. MARINE STRATUS ALONG THE COAST WILL BRING A
MIXTURE OF IFR/MVFR CIGS...WITH IFR VSBY POSSIBLE AFTER 09Z.

KPDX AND APPROACHES...VFR CONDITIONS CONTINUE THROUGH FRI.
THUNDERSTORMS POSSIBLE OVER THE CASCADES THROUGH 04Z. MVFR
STRATUS POSSIBLE BETWEEN 12-18Z. /64

&&

.MARINE...BENIGN CONDITIONS CONTINUE THROUGH THE FORECAST PERIOD.
WINDS WILL REMAIN GENERALLY BELOW SMALL CRAFT CRITERIA. MIXED SEAS
AROUND 4 TO 6 FT WILL CONTINUE THROUGH MUCH OF NEXT WEEK...WITH
SWELL TRAINS OUT OF THE W AND SW. /64

&&

.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 281626 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
926 AM PDT THU MAY 28 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. A CLOSED UPPER LOW OVER THE NORTHERN ROCKIES WILL
CONTINUE TO DRIFT SOUTHEAST TODAY. EXPECT A LITTLE MORE WARMING
TODAY...AND THEN INLAND DAYTIME TEMPERATURE SHOULD PEAK FRIDAY. THE
UPPER RIDGE STARTS TO FLATTEN SATURDAY. THE HIGHER CASCADES WILL
CONTINUE TO HAVE A SLIM THREAT OF LATE-DAY THUNDERSTORMS THE NEXT
COUPLE OF DAYS. THE NEXT UPPER LOW SWINGS CLOSER TO THE OREGON COAST
SUNDAY...RESULTING IN A LITTLE MORE COOLING BUT A BETTER CHANCE OF
CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE LAYER IS EXPECTED OVER
THE AREA EARLY NEXT WEEK.

&&

.MORNING UPDATE...
THE VISIBLE SATELLITE LOOP SHOWS PLENTY OF MARINE STRATUS AT THE
COAST THIS MORNING. A WEAK INLAND PUSH BROUGHT A THIN STRATUS LAYER
INTO THE COASTAL GAPS AND UP THE LOWER COLUMBIA. CLOUDS FILLED IN THE
I-5 CORRIDOR IN SW WASH AND REACHED THE PORTLAND/VANCOUVER METRO
AREA. THE REST OF THE WILLAMETTE VALLEY STAYED CLOUD FREE. EXPECT THE
INLAND STRATUS TO BURN OFF FAIRLY QUICKLY TODAY...LIKELY BY AROUND
18Z. THEN ANOTHER WARM DAY IS ON TAP FOR THE REGION. 850 MB TEMPS ARE
FCST TO REACH 14 TO 15 C WHICH SHOULD SUPPORT WIDESPREAD HIGHS INTO
THE LOW 80S FOR THE INTERIOR LOWLANDS. THE COAST WILL STAY MUCH
COOLER WITH CLOUDS HANGING ON FOR MUCH OF THE DAY AND A NW BREEZE OFF
OF THE OCEAN.

...PREVIOUS SHORT TERM DISCUSSION ISSUED 149 AM THU MAY 28...
.SHORT TERM...TODAY THROUGH SATURDAY...
WATER VAPOR LOOP SHOWS AN UPPER LOW OVER CENTRAL IDAHO...AND A SECOND
LOW NEAR 55N 131W. A 500 MB RIDGE AXIS EXTENDS BETWEEN 125W AND 130W.
WATER VAPOR ALSO SHOWS A DRY SLOT SLIDING SOUTH OVER VANCOUVER ISLAND
AND THE WA COAST. ON THE SMALLER SCALE...STRATUS HAS ALREADY REACHED
KKLS AT 08Z. THE 975 MB RH FORECAST FROM THE NAM VALID 09Z WAS A
LITTLE BEHIND...SHOWING THE 90 PCT OR GREATER VALUES A LITTLE FURTHER
WEST. MAIN FORECAST PROBLEM FOR TODAY AND FRIDAY WILL BE THE
POTENTIAL FOR THUNDERSTORMS FOR THE HIGHER CASCADES. THE UPPER LOW
THAT WAS CENTERED NEAR THE OREGON...WASHINGTON...IDAHO TRIPLE-POINT
00Z THU WILL CONTINUE TO SHIFT SOUTHEAST TODAY. THIS WILL ALLOW
NORTHWEST FLOW ALOFT OVER THE FORECAST AREA. HOWEVER...MODEL
SOUNDINGS FOR A POINT NEAR SANTIAM PASS...ESPECIALLY THE
NAM...MAINTAIN SOME DEGREE OF INSTABILITY FROM LATE-AFTERNOON THROUGH
THE EVENING TODAY AND FRI. BELIEVE THE MODELS MAY BE SLIGHTLY
OVER-DOING THE LOW-LEVEL DEW POINTS...THUS GENERATING
HIGHER CAPE VALUES. ACTUALLY THINK THE BEST CHANCE FOR CONVECTION...
ALBEIT SLIM...WILL BE OVER THE HIGHER S WA CASCADES.

EXPECT A THINNER MARINE LAYER TODAY. THE 06Z NAM DOES NOT SHOW MARINE
STRATUS REACHING KPDX...ALTHOUGH THE HI-RES ARC DOES INDICATE STRATUS
GETTING TO NEAR MULTNOMAH FALLS BY 15Z. HI-RES MODEL ALSO SUGGESTING
THE BEACHES WILL REMAIN CLOUDY. MAY BE A SHORT PERIOD OF SCATTERED
SKY CONDITIONS LATE IN THE DAY FROM ABOUT KONP NORTHWARD. MODEL 850
MB TEMPS FORECAST TO BE AROUND 15C TODAY IN THE WILLAMETTE VALLEY...
UP ABOUT 1 DEG FROM WED. THIS SHOULD PUT THE INLAND VALLEYS IN THE
LOWER 80S. WARMEST DAY LOOKS TO BE FRI WITH A SLIGHTLY WARMER START.
THE UPPER RIDGE STARTS TO FLATTEN A BIT LATE FRI AS AN UPPER LOW OVER
NRN BRITISH COLUMBIA SLOWLY DRIFTS SOUTH.

LITTLE CHANGE SAT WITH 500 MB HIGH PRES REMAINING OVER THE AREA. A
SLIGHT AMPLIFICATION IN THE RIDGE SAT AFTERNOON DUE TO A DEVELOPING
LOW MODELS SHOW NEAR 34N 138W SAT AFTERNOON. THIS ALSO INDUCES
SLIGHTLY MORE UNSTABLE SWLY FLOW ALOFT INTO THE REGION. WILL LEAVE
THE SLIGHT THREAT OF THUNDERSTORMS FOR THE LANE COUNTY CASCADES SAT
AFTERNOON. WEISHAAR

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEAK SHORTWAVE
RIDGING MOVES THROUGH THE AREA EARLY SAT NIGHT WITH AN APPROACHING
UPPER LEVEL LOW PRESSURE SYSTEM NEARING 130W BY EARLY SUN. AS THIS
LOW PRESSURE TRACKS INLAND...INCREASING CLOUDS AND MUCH COOLER
TEMPERATURES MOVE INTO THE REGION. SHOWERS WILL BEGIN BY LATE SUN
AFTERNOON OR EVENING AS THE SURFACE BOUNDARY SLIDES ONSHORE AND
ACROSS THE REGION...WITH A CHANCE FOR THUNDERSTORMS IN THE CASCADES
SOUTH OF AROUND MT HOOD. AS THIS UPPER LOW CONTINUES TO TRACK ALONG
A GENERALLY SOUTHWEST TO EAST-NORTHEAST PATH ACROSS THE REGION AND
THEN EAST OF THE CASCADES...EXPECT CONTINUED RAIN CHANCES AND COOLER
WEATHER TO CONTINUE THROUGH AROUND MIDWEEK. WHILE SOME MODEST
DIFFERENCES IN PATTERN EVOLUTION BETWEEN MODEL SOLUTIONS SUGGEST A
BIT OF UNCERTAINTY IN LOCATION AND TIMING OF RAINFALL AMOUNTS...THE
MODEL GUIDANCE REMAINS IN REMARKABLY DECENT AGREEMENT WITH RESPECT
TO THE SHOWERY PATTERN ALONG WITH TEMPERATURES AT OR A FEW DEGREES
BELOW SEASONAL NORMALS.
&&

.AVIATION...MOSTLY VFR INLAND WITH IFR STRATUS ALONG THE COLUMBIA
RIVER. EXPECT THIS STRATUS TO THIN AND LIFT THROUGH 18Z. DRY
NORTHERLY FLOW ALOFT WILL KEEP CONDITIONS INLAND VFR...WITH A
SLIGHT CHANCE OF THUNDERSTORMS OVER THE CASCADES BETWEEN 20-04Z.
MARINE LAYER ALONG THE COAST WILL CONTINUE TO BRING A MIXTURE OF
IFR/MVFR CIGS TODAY AND TONIGHT.

KPDX AND APPROACHES...IFR STRATUS AROUND 600 FT WILL CONTINUE TO
BURN OFF THROUGH 17Z. VFR CONDITIONS CONTINUE THROUGH FRI. /64

&&

.MARINE...NOT MUCH CHANGE OVERALL. HIGH PRES REMAINS LOCKED OVER
THE NE PAC...WITH WEAK PRES GRADIENTS. SEAS CONTINUE AS A MIX OF W
AND SW SWELL TRAINS...BUT OVERALL SEAS CONTINUE AROUND 5 TO 6 FT
THROUGH THE COMING WEEKEND.

&&

.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 281626 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
926 AM PDT THU MAY 28 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. A CLOSED UPPER LOW OVER THE NORTHERN ROCKIES WILL
CONTINUE TO DRIFT SOUTHEAST TODAY. EXPECT A LITTLE MORE WARMING
TODAY...AND THEN INLAND DAYTIME TEMPERATURE SHOULD PEAK FRIDAY. THE
UPPER RIDGE STARTS TO FLATTEN SATURDAY. THE HIGHER CASCADES WILL
CONTINUE TO HAVE A SLIM THREAT OF LATE-DAY THUNDERSTORMS THE NEXT
COUPLE OF DAYS. THE NEXT UPPER LOW SWINGS CLOSER TO THE OREGON COAST
SUNDAY...RESULTING IN A LITTLE MORE COOLING BUT A BETTER CHANCE OF
CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE LAYER IS EXPECTED OVER
THE AREA EARLY NEXT WEEK.

&&

.MORNING UPDATE...
THE VISIBLE SATELLITE LOOP SHOWS PLENTY OF MARINE STRATUS AT THE
COAST THIS MORNING. A WEAK INLAND PUSH BROUGHT A THIN STRATUS LAYER
INTO THE COASTAL GAPS AND UP THE LOWER COLUMBIA. CLOUDS FILLED IN THE
I-5 CORRIDOR IN SW WASH AND REACHED THE PORTLAND/VANCOUVER METRO
AREA. THE REST OF THE WILLAMETTE VALLEY STAYED CLOUD FREE. EXPECT THE
INLAND STRATUS TO BURN OFF FAIRLY QUICKLY TODAY...LIKELY BY AROUND
18Z. THEN ANOTHER WARM DAY IS ON TAP FOR THE REGION. 850 MB TEMPS ARE
FCST TO REACH 14 TO 15 C WHICH SHOULD SUPPORT WIDESPREAD HIGHS INTO
THE LOW 80S FOR THE INTERIOR LOWLANDS. THE COAST WILL STAY MUCH
COOLER WITH CLOUDS HANGING ON FOR MUCH OF THE DAY AND A NW BREEZE OFF
OF THE OCEAN.

...PREVIOUS SHORT TERM DISCUSSION ISSUED 149 AM THU MAY 28...
.SHORT TERM...TODAY THROUGH SATURDAY...
WATER VAPOR LOOP SHOWS AN UPPER LOW OVER CENTRAL IDAHO...AND A SECOND
LOW NEAR 55N 131W. A 500 MB RIDGE AXIS EXTENDS BETWEEN 125W AND 130W.
WATER VAPOR ALSO SHOWS A DRY SLOT SLIDING SOUTH OVER VANCOUVER ISLAND
AND THE WA COAST. ON THE SMALLER SCALE...STRATUS HAS ALREADY REACHED
KKLS AT 08Z. THE 975 MB RH FORECAST FROM THE NAM VALID 09Z WAS A
LITTLE BEHIND...SHOWING THE 90 PCT OR GREATER VALUES A LITTLE FURTHER
WEST. MAIN FORECAST PROBLEM FOR TODAY AND FRIDAY WILL BE THE
POTENTIAL FOR THUNDERSTORMS FOR THE HIGHER CASCADES. THE UPPER LOW
THAT WAS CENTERED NEAR THE OREGON...WASHINGTON...IDAHO TRIPLE-POINT
00Z THU WILL CONTINUE TO SHIFT SOUTHEAST TODAY. THIS WILL ALLOW
NORTHWEST FLOW ALOFT OVER THE FORECAST AREA. HOWEVER...MODEL
SOUNDINGS FOR A POINT NEAR SANTIAM PASS...ESPECIALLY THE
NAM...MAINTAIN SOME DEGREE OF INSTABILITY FROM LATE-AFTERNOON THROUGH
THE EVENING TODAY AND FRI. BELIEVE THE MODELS MAY BE SLIGHTLY
OVER-DOING THE LOW-LEVEL DEW POINTS...THUS GENERATING
HIGHER CAPE VALUES. ACTUALLY THINK THE BEST CHANCE FOR CONVECTION...
ALBEIT SLIM...WILL BE OVER THE HIGHER S WA CASCADES.

EXPECT A THINNER MARINE LAYER TODAY. THE 06Z NAM DOES NOT SHOW MARINE
STRATUS REACHING KPDX...ALTHOUGH THE HI-RES ARC DOES INDICATE STRATUS
GETTING TO NEAR MULTNOMAH FALLS BY 15Z. HI-RES MODEL ALSO SUGGESTING
THE BEACHES WILL REMAIN CLOUDY. MAY BE A SHORT PERIOD OF SCATTERED
SKY CONDITIONS LATE IN THE DAY FROM ABOUT KONP NORTHWARD. MODEL 850
MB TEMPS FORECAST TO BE AROUND 15C TODAY IN THE WILLAMETTE VALLEY...
UP ABOUT 1 DEG FROM WED. THIS SHOULD PUT THE INLAND VALLEYS IN THE
LOWER 80S. WARMEST DAY LOOKS TO BE FRI WITH A SLIGHTLY WARMER START.
THE UPPER RIDGE STARTS TO FLATTEN A BIT LATE FRI AS AN UPPER LOW OVER
NRN BRITISH COLUMBIA SLOWLY DRIFTS SOUTH.

LITTLE CHANGE SAT WITH 500 MB HIGH PRES REMAINING OVER THE AREA. A
SLIGHT AMPLIFICATION IN THE RIDGE SAT AFTERNOON DUE TO A DEVELOPING
LOW MODELS SHOW NEAR 34N 138W SAT AFTERNOON. THIS ALSO INDUCES
SLIGHTLY MORE UNSTABLE SWLY FLOW ALOFT INTO THE REGION. WILL LEAVE
THE SLIGHT THREAT OF THUNDERSTORMS FOR THE LANE COUNTY CASCADES SAT
AFTERNOON. WEISHAAR

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEAK SHORTWAVE
RIDGING MOVES THROUGH THE AREA EARLY SAT NIGHT WITH AN APPROACHING
UPPER LEVEL LOW PRESSURE SYSTEM NEARING 130W BY EARLY SUN. AS THIS
LOW PRESSURE TRACKS INLAND...INCREASING CLOUDS AND MUCH COOLER
TEMPERATURES MOVE INTO THE REGION. SHOWERS WILL BEGIN BY LATE SUN
AFTERNOON OR EVENING AS THE SURFACE BOUNDARY SLIDES ONSHORE AND
ACROSS THE REGION...WITH A CHANCE FOR THUNDERSTORMS IN THE CASCADES
SOUTH OF AROUND MT HOOD. AS THIS UPPER LOW CONTINUES TO TRACK ALONG
A GENERALLY SOUTHWEST TO EAST-NORTHEAST PATH ACROSS THE REGION AND
THEN EAST OF THE CASCADES...EXPECT CONTINUED RAIN CHANCES AND COOLER
WEATHER TO CONTINUE THROUGH AROUND MIDWEEK. WHILE SOME MODEST
DIFFERENCES IN PATTERN EVOLUTION BETWEEN MODEL SOLUTIONS SUGGEST A
BIT OF UNCERTAINTY IN LOCATION AND TIMING OF RAINFALL AMOUNTS...THE
MODEL GUIDANCE REMAINS IN REMARKABLY DECENT AGREEMENT WITH RESPECT
TO THE SHOWERY PATTERN ALONG WITH TEMPERATURES AT OR A FEW DEGREES
BELOW SEASONAL NORMALS.
&&

.AVIATION...MOSTLY VFR INLAND WITH IFR STRATUS ALONG THE COLUMBIA
RIVER. EXPECT THIS STRATUS TO THIN AND LIFT THROUGH 18Z. DRY
NORTHERLY FLOW ALOFT WILL KEEP CONDITIONS INLAND VFR...WITH A
SLIGHT CHANCE OF THUNDERSTORMS OVER THE CASCADES BETWEEN 20-04Z.
MARINE LAYER ALONG THE COAST WILL CONTINUE TO BRING A MIXTURE OF
IFR/MVFR CIGS TODAY AND TONIGHT.

KPDX AND APPROACHES...IFR STRATUS AROUND 600 FT WILL CONTINUE TO
BURN OFF THROUGH 17Z. VFR CONDITIONS CONTINUE THROUGH FRI. /64

&&

.MARINE...NOT MUCH CHANGE OVERALL. HIGH PRES REMAINS LOCKED OVER
THE NE PAC...WITH WEAK PRES GRADIENTS. SEAS CONTINUE AS A MIX OF W
AND SW SWELL TRAINS...BUT OVERALL SEAS CONTINUE AROUND 5 TO 6 FT
THROUGH THE COMING WEEKEND.

&&

.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 281626 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
926 AM PDT THU MAY 28 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. A CLOSED UPPER LOW OVER THE NORTHERN ROCKIES WILL
CONTINUE TO DRIFT SOUTHEAST TODAY. EXPECT A LITTLE MORE WARMING
TODAY...AND THEN INLAND DAYTIME TEMPERATURE SHOULD PEAK FRIDAY. THE
UPPER RIDGE STARTS TO FLATTEN SATURDAY. THE HIGHER CASCADES WILL
CONTINUE TO HAVE A SLIM THREAT OF LATE-DAY THUNDERSTORMS THE NEXT
COUPLE OF DAYS. THE NEXT UPPER LOW SWINGS CLOSER TO THE OREGON COAST
SUNDAY...RESULTING IN A LITTLE MORE COOLING BUT A BETTER CHANCE OF
CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE LAYER IS EXPECTED OVER
THE AREA EARLY NEXT WEEK.

&&

.MORNING UPDATE...
THE VISIBLE SATELLITE LOOP SHOWS PLENTY OF MARINE STRATUS AT THE
COAST THIS MORNING. A WEAK INLAND PUSH BROUGHT A THIN STRATUS LAYER
INTO THE COASTAL GAPS AND UP THE LOWER COLUMBIA. CLOUDS FILLED IN THE
I-5 CORRIDOR IN SW WASH AND REACHED THE PORTLAND/VANCOUVER METRO
AREA. THE REST OF THE WILLAMETTE VALLEY STAYED CLOUD FREE. EXPECT THE
INLAND STRATUS TO BURN OFF FAIRLY QUICKLY TODAY...LIKELY BY AROUND
18Z. THEN ANOTHER WARM DAY IS ON TAP FOR THE REGION. 850 MB TEMPS ARE
FCST TO REACH 14 TO 15 C WHICH SHOULD SUPPORT WIDESPREAD HIGHS INTO
THE LOW 80S FOR THE INTERIOR LOWLANDS. THE COAST WILL STAY MUCH
COOLER WITH CLOUDS HANGING ON FOR MUCH OF THE DAY AND A NW BREEZE OFF
OF THE OCEAN.

...PREVIOUS SHORT TERM DISCUSSION ISSUED 149 AM THU MAY 28...
.SHORT TERM...TODAY THROUGH SATURDAY...
WATER VAPOR LOOP SHOWS AN UPPER LOW OVER CENTRAL IDAHO...AND A SECOND
LOW NEAR 55N 131W. A 500 MB RIDGE AXIS EXTENDS BETWEEN 125W AND 130W.
WATER VAPOR ALSO SHOWS A DRY SLOT SLIDING SOUTH OVER VANCOUVER ISLAND
AND THE WA COAST. ON THE SMALLER SCALE...STRATUS HAS ALREADY REACHED
KKLS AT 08Z. THE 975 MB RH FORECAST FROM THE NAM VALID 09Z WAS A
LITTLE BEHIND...SHOWING THE 90 PCT OR GREATER VALUES A LITTLE FURTHER
WEST. MAIN FORECAST PROBLEM FOR TODAY AND FRIDAY WILL BE THE
POTENTIAL FOR THUNDERSTORMS FOR THE HIGHER CASCADES. THE UPPER LOW
THAT WAS CENTERED NEAR THE OREGON...WASHINGTON...IDAHO TRIPLE-POINT
00Z THU WILL CONTINUE TO SHIFT SOUTHEAST TODAY. THIS WILL ALLOW
NORTHWEST FLOW ALOFT OVER THE FORECAST AREA. HOWEVER...MODEL
SOUNDINGS FOR A POINT NEAR SANTIAM PASS...ESPECIALLY THE
NAM...MAINTAIN SOME DEGREE OF INSTABILITY FROM LATE-AFTERNOON THROUGH
THE EVENING TODAY AND FRI. BELIEVE THE MODELS MAY BE SLIGHTLY
OVER-DOING THE LOW-LEVEL DEW POINTS...THUS GENERATING
HIGHER CAPE VALUES. ACTUALLY THINK THE BEST CHANCE FOR CONVECTION...
ALBEIT SLIM...WILL BE OVER THE HIGHER S WA CASCADES.

EXPECT A THINNER MARINE LAYER TODAY. THE 06Z NAM DOES NOT SHOW MARINE
STRATUS REACHING KPDX...ALTHOUGH THE HI-RES ARC DOES INDICATE STRATUS
GETTING TO NEAR MULTNOMAH FALLS BY 15Z. HI-RES MODEL ALSO SUGGESTING
THE BEACHES WILL REMAIN CLOUDY. MAY BE A SHORT PERIOD OF SCATTERED
SKY CONDITIONS LATE IN THE DAY FROM ABOUT KONP NORTHWARD. MODEL 850
MB TEMPS FORECAST TO BE AROUND 15C TODAY IN THE WILLAMETTE VALLEY...
UP ABOUT 1 DEG FROM WED. THIS SHOULD PUT THE INLAND VALLEYS IN THE
LOWER 80S. WARMEST DAY LOOKS TO BE FRI WITH A SLIGHTLY WARMER START.
THE UPPER RIDGE STARTS TO FLATTEN A BIT LATE FRI AS AN UPPER LOW OVER
NRN BRITISH COLUMBIA SLOWLY DRIFTS SOUTH.

LITTLE CHANGE SAT WITH 500 MB HIGH PRES REMAINING OVER THE AREA. A
SLIGHT AMPLIFICATION IN THE RIDGE SAT AFTERNOON DUE TO A DEVELOPING
LOW MODELS SHOW NEAR 34N 138W SAT AFTERNOON. THIS ALSO INDUCES
SLIGHTLY MORE UNSTABLE SWLY FLOW ALOFT INTO THE REGION. WILL LEAVE
THE SLIGHT THREAT OF THUNDERSTORMS FOR THE LANE COUNTY CASCADES SAT
AFTERNOON. WEISHAAR

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEAK SHORTWAVE
RIDGING MOVES THROUGH THE AREA EARLY SAT NIGHT WITH AN APPROACHING
UPPER LEVEL LOW PRESSURE SYSTEM NEARING 130W BY EARLY SUN. AS THIS
LOW PRESSURE TRACKS INLAND...INCREASING CLOUDS AND MUCH COOLER
TEMPERATURES MOVE INTO THE REGION. SHOWERS WILL BEGIN BY LATE SUN
AFTERNOON OR EVENING AS THE SURFACE BOUNDARY SLIDES ONSHORE AND
ACROSS THE REGION...WITH A CHANCE FOR THUNDERSTORMS IN THE CASCADES
SOUTH OF AROUND MT HOOD. AS THIS UPPER LOW CONTINUES TO TRACK ALONG
A GENERALLY SOUTHWEST TO EAST-NORTHEAST PATH ACROSS THE REGION AND
THEN EAST OF THE CASCADES...EXPECT CONTINUED RAIN CHANCES AND COOLER
WEATHER TO CONTINUE THROUGH AROUND MIDWEEK. WHILE SOME MODEST
DIFFERENCES IN PATTERN EVOLUTION BETWEEN MODEL SOLUTIONS SUGGEST A
BIT OF UNCERTAINTY IN LOCATION AND TIMING OF RAINFALL AMOUNTS...THE
MODEL GUIDANCE REMAINS IN REMARKABLY DECENT AGREEMENT WITH RESPECT
TO THE SHOWERY PATTERN ALONG WITH TEMPERATURES AT OR A FEW DEGREES
BELOW SEASONAL NORMALS.
&&

.AVIATION...MOSTLY VFR INLAND WITH IFR STRATUS ALONG THE COLUMBIA
RIVER. EXPECT THIS STRATUS TO THIN AND LIFT THROUGH 18Z. DRY
NORTHERLY FLOW ALOFT WILL KEEP CONDITIONS INLAND VFR...WITH A
SLIGHT CHANCE OF THUNDERSTORMS OVER THE CASCADES BETWEEN 20-04Z.
MARINE LAYER ALONG THE COAST WILL CONTINUE TO BRING A MIXTURE OF
IFR/MVFR CIGS TODAY AND TONIGHT.

KPDX AND APPROACHES...IFR STRATUS AROUND 600 FT WILL CONTINUE TO
BURN OFF THROUGH 17Z. VFR CONDITIONS CONTINUE THROUGH FRI. /64

&&

.MARINE...NOT MUCH CHANGE OVERALL. HIGH PRES REMAINS LOCKED OVER
THE NE PAC...WITH WEAK PRES GRADIENTS. SEAS CONTINUE AS A MIX OF W
AND SW SWELL TRAINS...BUT OVERALL SEAS CONTINUE AROUND 5 TO 6 FT
THROUGH THE COMING WEEKEND.

&&

.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 281626 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
926 AM PDT THU MAY 28 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. A CLOSED UPPER LOW OVER THE NORTHERN ROCKIES WILL
CONTINUE TO DRIFT SOUTHEAST TODAY. EXPECT A LITTLE MORE WARMING
TODAY...AND THEN INLAND DAYTIME TEMPERATURE SHOULD PEAK FRIDAY. THE
UPPER RIDGE STARTS TO FLATTEN SATURDAY. THE HIGHER CASCADES WILL
CONTINUE TO HAVE A SLIM THREAT OF LATE-DAY THUNDERSTORMS THE NEXT
COUPLE OF DAYS. THE NEXT UPPER LOW SWINGS CLOSER TO THE OREGON COAST
SUNDAY...RESULTING IN A LITTLE MORE COOLING BUT A BETTER CHANCE OF
CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE LAYER IS EXPECTED OVER
THE AREA EARLY NEXT WEEK.

&&

.MORNING UPDATE...
THE VISIBLE SATELLITE LOOP SHOWS PLENTY OF MARINE STRATUS AT THE
COAST THIS MORNING. A WEAK INLAND PUSH BROUGHT A THIN STRATUS LAYER
INTO THE COASTAL GAPS AND UP THE LOWER COLUMBIA. CLOUDS FILLED IN THE
I-5 CORRIDOR IN SW WASH AND REACHED THE PORTLAND/VANCOUVER METRO
AREA. THE REST OF THE WILLAMETTE VALLEY STAYED CLOUD FREE. EXPECT THE
INLAND STRATUS TO BURN OFF FAIRLY QUICKLY TODAY...LIKELY BY AROUND
18Z. THEN ANOTHER WARM DAY IS ON TAP FOR THE REGION. 850 MB TEMPS ARE
FCST TO REACH 14 TO 15 C WHICH SHOULD SUPPORT WIDESPREAD HIGHS INTO
THE LOW 80S FOR THE INTERIOR LOWLANDS. THE COAST WILL STAY MUCH
COOLER WITH CLOUDS HANGING ON FOR MUCH OF THE DAY AND A NW BREEZE OFF
OF THE OCEAN.

...PREVIOUS SHORT TERM DISCUSSION ISSUED 149 AM THU MAY 28...
.SHORT TERM...TODAY THROUGH SATURDAY...
WATER VAPOR LOOP SHOWS AN UPPER LOW OVER CENTRAL IDAHO...AND A SECOND
LOW NEAR 55N 131W. A 500 MB RIDGE AXIS EXTENDS BETWEEN 125W AND 130W.
WATER VAPOR ALSO SHOWS A DRY SLOT SLIDING SOUTH OVER VANCOUVER ISLAND
AND THE WA COAST. ON THE SMALLER SCALE...STRATUS HAS ALREADY REACHED
KKLS AT 08Z. THE 975 MB RH FORECAST FROM THE NAM VALID 09Z WAS A
LITTLE BEHIND...SHOWING THE 90 PCT OR GREATER VALUES A LITTLE FURTHER
WEST. MAIN FORECAST PROBLEM FOR TODAY AND FRIDAY WILL BE THE
POTENTIAL FOR THUNDERSTORMS FOR THE HIGHER CASCADES. THE UPPER LOW
THAT WAS CENTERED NEAR THE OREGON...WASHINGTON...IDAHO TRIPLE-POINT
00Z THU WILL CONTINUE TO SHIFT SOUTHEAST TODAY. THIS WILL ALLOW
NORTHWEST FLOW ALOFT OVER THE FORECAST AREA. HOWEVER...MODEL
SOUNDINGS FOR A POINT NEAR SANTIAM PASS...ESPECIALLY THE
NAM...MAINTAIN SOME DEGREE OF INSTABILITY FROM LATE-AFTERNOON THROUGH
THE EVENING TODAY AND FRI. BELIEVE THE MODELS MAY BE SLIGHTLY
OVER-DOING THE LOW-LEVEL DEW POINTS...THUS GENERATING
HIGHER CAPE VALUES. ACTUALLY THINK THE BEST CHANCE FOR CONVECTION...
ALBEIT SLIM...WILL BE OVER THE HIGHER S WA CASCADES.

EXPECT A THINNER MARINE LAYER TODAY. THE 06Z NAM DOES NOT SHOW MARINE
STRATUS REACHING KPDX...ALTHOUGH THE HI-RES ARC DOES INDICATE STRATUS
GETTING TO NEAR MULTNOMAH FALLS BY 15Z. HI-RES MODEL ALSO SUGGESTING
THE BEACHES WILL REMAIN CLOUDY. MAY BE A SHORT PERIOD OF SCATTERED
SKY CONDITIONS LATE IN THE DAY FROM ABOUT KONP NORTHWARD. MODEL 850
MB TEMPS FORECAST TO BE AROUND 15C TODAY IN THE WILLAMETTE VALLEY...
UP ABOUT 1 DEG FROM WED. THIS SHOULD PUT THE INLAND VALLEYS IN THE
LOWER 80S. WARMEST DAY LOOKS TO BE FRI WITH A SLIGHTLY WARMER START.
THE UPPER RIDGE STARTS TO FLATTEN A BIT LATE FRI AS AN UPPER LOW OVER
NRN BRITISH COLUMBIA SLOWLY DRIFTS SOUTH.

LITTLE CHANGE SAT WITH 500 MB HIGH PRES REMAINING OVER THE AREA. A
SLIGHT AMPLIFICATION IN THE RIDGE SAT AFTERNOON DUE TO A DEVELOPING
LOW MODELS SHOW NEAR 34N 138W SAT AFTERNOON. THIS ALSO INDUCES
SLIGHTLY MORE UNSTABLE SWLY FLOW ALOFT INTO THE REGION. WILL LEAVE
THE SLIGHT THREAT OF THUNDERSTORMS FOR THE LANE COUNTY CASCADES SAT
AFTERNOON. WEISHAAR

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEAK SHORTWAVE
RIDGING MOVES THROUGH THE AREA EARLY SAT NIGHT WITH AN APPROACHING
UPPER LEVEL LOW PRESSURE SYSTEM NEARING 130W BY EARLY SUN. AS THIS
LOW PRESSURE TRACKS INLAND...INCREASING CLOUDS AND MUCH COOLER
TEMPERATURES MOVE INTO THE REGION. SHOWERS WILL BEGIN BY LATE SUN
AFTERNOON OR EVENING AS THE SURFACE BOUNDARY SLIDES ONSHORE AND
ACROSS THE REGION...WITH A CHANCE FOR THUNDERSTORMS IN THE CASCADES
SOUTH OF AROUND MT HOOD. AS THIS UPPER LOW CONTINUES TO TRACK ALONG
A GENERALLY SOUTHWEST TO EAST-NORTHEAST PATH ACROSS THE REGION AND
THEN EAST OF THE CASCADES...EXPECT CONTINUED RAIN CHANCES AND COOLER
WEATHER TO CONTINUE THROUGH AROUND MIDWEEK. WHILE SOME MODEST
DIFFERENCES IN PATTERN EVOLUTION BETWEEN MODEL SOLUTIONS SUGGEST A
BIT OF UNCERTAINTY IN LOCATION AND TIMING OF RAINFALL AMOUNTS...THE
MODEL GUIDANCE REMAINS IN REMARKABLY DECENT AGREEMENT WITH RESPECT
TO THE SHOWERY PATTERN ALONG WITH TEMPERATURES AT OR A FEW DEGREES
BELOW SEASONAL NORMALS.
&&

.AVIATION...MOSTLY VFR INLAND WITH IFR STRATUS ALONG THE COLUMBIA
RIVER. EXPECT THIS STRATUS TO THIN AND LIFT THROUGH 18Z. DRY
NORTHERLY FLOW ALOFT WILL KEEP CONDITIONS INLAND VFR...WITH A
SLIGHT CHANCE OF THUNDERSTORMS OVER THE CASCADES BETWEEN 20-04Z.
MARINE LAYER ALONG THE COAST WILL CONTINUE TO BRING A MIXTURE OF
IFR/MVFR CIGS TODAY AND TONIGHT.

KPDX AND APPROACHES...IFR STRATUS AROUND 600 FT WILL CONTINUE TO
BURN OFF THROUGH 17Z. VFR CONDITIONS CONTINUE THROUGH FRI. /64

&&

.MARINE...NOT MUCH CHANGE OVERALL. HIGH PRES REMAINS LOCKED OVER
THE NE PAC...WITH WEAK PRES GRADIENTS. SEAS CONTINUE AS A MIX OF W
AND SW SWELL TRAINS...BUT OVERALL SEAS CONTINUE AROUND 5 TO 6 FT
THROUGH THE COMING WEEKEND.

&&

.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 280850 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
149 AM PDT THU MAY 28 2015

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER THE FORECAST AREA
THROUGH SATURDAY. THE CLOSED UPPER LOW OVER CENTRAL IDAHO TONIGHT
WILL CONTINUE TO DRIFT SOUTHEAST TODAY. EXPECT A LITTLE MORE WARMING
TODAY...AND THEN INLAND DAYTIME TEMPERATURE SHOULD PEAK FRIDAY. THE
UPPER RIDGE STARTS TO FLATTEN SATURDAY. THE HIGHER CASCADES WILL
CONTINUE TO HAVE A SLIM THREAT OF LATE-DAY THUNDERSTORMS THE NEXT
COUPLE OF DAYS. THE NEXT UPPER LOW SWINGS CLOSER TO THE OREGON COAST
SUNDAY...RESULTING IN A LITTLE MORE COOLING BUT A BETTER CHANCE OF
CASCADE THUNDERSTORMS. A MUCH DEEPER MARINE LAYER IS EXPECTED OVER
THE AREA EARLY NEXT WEEK.

&&

.SHORT TERM...TODAY THROUGH SATURDAY...WATER VAPOR LOOP SHOWS ONE
UPPER LOW OVER CENTRAL IDAHO...AND A SECOND LOW NEAR 55N 131W. A 500
MB RIDGE AXIS EXTENDS BETWEEN 125W AND 130W. WATER VAPOR ALSO SHOWS A
DRY SLOT SLIDING SOUTH OVER VANCOUVER ISLAND AND THE WA COAST. ON THE
SMALLER SCALE...STRATUS HAS ALREADY REACHED KKLS AT 08Z. THE 975 MB
RH FORECAST FROM THE NAM VALID 09Z WAS A LITTLE BEHIND...SHOWING THE
90 PCT OR GREATER VALUES A LITTLE FURTHER WEST. MAIN FORECAST PROBLEM
FOR TODAY AND FRIDAY WILL BE THE POTENTIAL FOR THUNDERSTORMS FOR THE
HIGHER CASCADES. THE UPPER LOW THAT WAS CENTERED NEAR THE
OREGON...WASHINGTON...IDAHO TRIPLE-POINT 00Z THU WILL CONTINUE TO
SHIFT SOUTHEAST TODAY. THIS WILL ALLOW NORTHWEST FLOW ALOFT OVER THE
FORECAST AREA. HOWEVER...MODEL SOUNDINGS FOR A POINT NEAR SANTIAM
PASS...ESPECIALLY THE NAM...MAINTAIN SOME DEGREE OF INSTABILITY FROM
LATE-AFTERNOON THROUGH THE EVENING TODAY AND FRI. BELIEVE THE MODELS
MAY BE SLIGHTLY OVER-DOING THE LOW-LEVEL DEW POINTS...THUS GENERATING
HIGHER CAPE VALUES. ACTUALLY THINK THE BEST CHANCE FOR CONVECTION...
ALBEIT SLIM...WILL BE OVER THE HIGHER S WA CASCADES.

EXPECT A THINNER MARINE LAYER TODAY. THE 06Z NAM DOES NOT SHOW MARINE
STRATUS REACHING KPDX...ALTHOUGH THE HI-RES ARW DOES INDICATE STRATUS
GETTING TO NEAR MULTNOMAH FALLS BY 15Z. HI-RES MODEL ALSO SUGGESTING
THE BEACHES WILL REMAIN CLOUDY. MAY BE A SHORT PERIOD OF SCATTERED
SKY CONDITIONS LATE IN THE DAY FROM ABOUT KONP NORTHWARD. MODEL 850
MB TEMPS FORECAST TO BE AROUND 15C TODAY IN THE WILLAMETTE VALLEY...
UP ABOUT 1 DEG FROM WED. THIS SHOULD PUT THE INLAND VALLEYS IN THE
LOWER 80S. WARMEST DAY LOOKS TO BE FRI WITH A SLIGHTLY WARMER START.
THE UPPER RIDGE STARTS TO FLATTEN A BIT LATE FRI AS AN UPPER LOW OVER
NRN BRITISH COLUMBIA SLOWLY DRIFTS SOUTH.

LITTLE CHANGE SAT WITH 500 MB HIGH PRES REMAINING OVER THE AREA. A
SLIGHT AMPLIFICATION IN THE RIDGE SAT AFTERNOON DUE TO A DEVELOPING
LOW MODELS SHOW NEAR 34N 138W SAT AFTERNOON. THIS ALSO INDUCES
SLIGHTLY MORE UNSTABLE SWLY FLOW ALOFT INTO THE REGION. WILL LEAVE
THE SLIGHT THREAT OF THUNDERSTORMS FOR THE LANE COUNTY CASCADES SAT
AFTERNOON. WEISHAAR

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEAK SHORTWAVE
RIDGING MOVES THROUGH THE AREA EARLY SAT NIGHT WITH AN APPROACHING
UPPER LEVEL LOW PRESSURE SYSTEM NEARING 130W BY EARLY SUN. AS THIS
LOW PRESSURE TRACKS INLAND...INCREASING CLOUDS AND MUCH COOLER
TEMPERATURES MOVE INTO THE REGION. SHOWERS WILL BEGIN BY LATE SUN
AFTERNOON OR EVENING AS THE SURFACE BOUNDARY SLIDES ONSHORE AND
ACROSS THE REGION...WITH A CHANCE FOR THUNDERSTORMS IN THE CASCADES
SOUTH OF AROUND MT HOOD. AS THIS UPPER LOW CONTINUES TO TRACK ALONG
A GENERALLY SOUTHWEST TO EAST-NORTHEAST PATH ACROSS THE REGION AND
THEN EAST OF THE CASCADES...EXPECT CONTINUED RAIN CHANCES AND COOLER
WEATHER TO CONTINUE THROUGH AROUND MIDWEEK. WHILE SOME MODEST
DIFFERENCES IN PATTERN EVOLUTION BETWEEN MODEL SOLUTIONS SUGGEST A
BIT OF UNCERTAINTY IN LOCATION AND TIMING OF RAINFALL AMOUNTS...THE
MODEL GUIDANCE REMAINS IN REMARKABLY DECENT AGREEMENT WITH RESPECT
TO THE SHOWERY PATTERN ALONG WITH TEMPERATURES AT OR A FEW DEGREES
BELOW SEASONAL NORMALS.
&&

.AVIATION...VFR TODAY OVER MUCH OF THE REGION...WITH DRIER STABLE
N TO NW FLOW ALOFT. SHALLOW MARINE LAYER OVER THE PAC WILL KEEP
IFR STRATUS ON THE COAST JAMMED AGAINST THE COAST RANGE. TOPS
LIKELY IN 1000 TO 1200 FT RANGE. DO HAVE POCKETS OF STRATUS
EXTENDING INTO THE COAST RANGE AND UP THE COLUMBIA RIVER THIS
AM. STRATUS AT KKLS WILL CONTINUE PUSHING UPSTREAM...REACHING KPDX
AND KTTD ARUOND 12Z...THEN STRATUS WILL PUSH BIT MORE TO THE SOUTH
AGAINST THE CASCADES FOOTHILLS. BUT THOSE INLAND CLOUDS WILL BURN
OFF BETWEEN 16Z AND 18Z.

KPDX AND APPROACHES...VFR TODAY WITH DRY STABLE AIR MASS ALOFT.
LIKE WED AM...LOW STRATUS WITH CIGS NEAR 800 FT WILL ARRIVE FROM
THE N AROUND 12Z...BUT WILL BURN OUT BETWEEN 16Z AND 17Z. ROCKEY.
&&

.MARINE...NOT MUCH CHANGE OVERALL. HIGH PRES REMAINS LOCKED OVER
THE NE PAC...WITH WEAK PRES GRADIENTS. SEAS CONTINUE AS A MIX OF W
AND SW SWELL TRAINS...BUT OVERALL SEAS CONTINUE AROUND 5 TO 6 FT
THROUGH THE COMING WEEKEND.
&&

.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 280343 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
837 PM PDT WED MAY 27 2015


.SYNOPSIS...THE UPPER LEVEL CLOSED LOW THAT HAS BEEN OVER THE PAC NW
FOR THE PAST FEW DAYS IS NOW CENTERED OVER WRN IDAHO. THE LOW WILL
CONTINUE TO PUSH GRADUALLY EASTWARD INTO THE NRN ROCKIES TONIGHT AND
THU. AN UPPER LEVEL RIDGE WILL BUILD IN BEHIND...BRINGING A WARMER
AND DRIER AIR MASS FOR THE REST OF THE WEEK AND MUCH OF THE WEEKEND.
ANOTHER UPPER LEVEL LOW WILL APPROACH FROM THE SW LATE LATE SUN INTO
MON...BRINGING COOLER TEMPS AND A THREAT FOR SHOWERS AND
THUNDERSTORMS FOR EARLY NEXT WEEK.

&&

.UPDATE...SOME THUNDERSTORMS FIRED UP OVER THE SOUTH WA CASCADES
THIS AFTERNOON AND EARLY EVENING...BUT IS NOW ON THE DECREASE.WHILE
THE LOW IS FURTHER INLAND THAN TUE A SHORTWAVE DROPPED INTO EASTERN
WA THIS AFTERNOON BRINING MORE NORTHERLY FLOW ALOFT COMPARED TO THE
NWLY FLOW TUE. MODEL SOUNDINGS IN THE AREA OF CONVECTION OVER
SKAMANIA COUNTY SHOWED THIN CAPE ABOVE THE MOIST LAYER AROUND 850 MB.
  MARGINAL INSTABILITY RETURNS OVER THE CASCADES THU AFTERNOON AND
EARLY EVENING. MOISTURE WILL BE MORE LIMITED THAN TODAY AND THE WEST
TO NORTHWEST WIND ALOFT SHOULD LIMIT CONVECTION NEAR AND EAST OF THE
CASCADE CREST.

A MILD EVENING WITH MOSTLY CLEAR SKIES AND TEMPERATURES IN THE UPPER
60S TO MID 70S INLAND. THE MARINE LAYER IS WORKING ITS WAY ONSHORE
WITH CLOUDY SKIES AT THE COAST AND TEMPERATURES DOWN INTO THE MID
50S.  SHOULD SEE STRATUS SEEP INLAND OVERNIGHT INTO THU
MORNING...PARTICULARLY ON THE LOWER COLUMBIA RIVER TO THE PORTLAND
AREA AND SOME IN THE  SOUTH WILLAMETTE VALLEY. HOWEVER WITH THE
SHALLOWER MARINE LAYER THERE WILL BE MORE SUNSHINE TOMORROW.
/26

PREVIOUS SHORT TERM DISCUSSION FOLLOWS...
SHORT TERM TONIGHT THROUGH SATURDAY...THE PERSISTENT CLOSED UPPER
LEVEL LOW THAT HAS BEEN OVER THE PAC NW FOR THE PAST SEVERAL DAYS IS
NOW CENTERED OVER WRN IDAHO THIS AFTERNOON. SIMILAR TO
YESTERDAY...AFTERNOON SHOWERS AND THUNDERSTORMS ARE DEVELOPING UNDER
THE COLD LOW OVER ERN WASHINGTON AND OREGON. A FEW SHOWERS ARE
DEVELOPING ALONG THE E SLOPES OF THE SOUTH WASHINGTON CASCADES...SO
WILL CONTINUE TO KEEP A SLIGHT CHANCE OF THUNDER ALONG THE CREST
THROUGH EARLY THIS EVENING. HOWEVER...MOST OF THE ACTIVITY SHOULD
AGAIN REMAIN EAST OF THE CREST. OTHERWISE...A VERY NICE DAY IS
UNDERWAY ACROSS THE FCST AREA. THE THINNER MARINE STRATUS LAYER TODAY
BURNED OFF QUITE A BIT SOONER THAN WE SAW THE PAST COUPLE OF
DAYS...ALTHOUGH SOME STRATOCUMULUS HAVE FORMED OVER THE PAST COUPLE
OF HOURS DUE TO DAYTIME LOW LEVEL MIXING. EXPECT AFTERNOON HIGHS TO
REACH INTO THE MID TO UPPER 70S FOR MOST EVERYONE IN THE INTERIOR
LOWLANDS...WHILE THE COAST WILL REMAIN IN THE 60S WITH NORTHWESTERLY
ONSHORE FLOW.

THE UPPER LOW WILL DRIFT FURTHER EAST TONIGHT AND THU. THIS WILL
ALLOW AN UPPER LEVEL RIDGE TO PUSH TOWARD THE PAC NW...BRINGING A
GRADUALLY WARMER AND DRIER AIR MASS TO THE REGION. EXPECT THE MARINE
STRATUS TO PUSH TO BE EVEN WEAKER TONIGHT...WITH THE MAJORITY OF
INLAND VALLEY LOCATIONS REMAINING CLOUD FREE. 850 MB TEMPS ARE
EXPECTED TO INCREASE TO 13 TO 15 C TOMORROW...WHICH SHOULD RESULT IN
AFTER HIGHS REACHING INTO THE 80S FOR MOST OF THE INTERIOR LOWLANDS.
THE COAST WILL AGAIN STAY COOLER WITH THE NW LOW LEVEL FLOW.

THE WARM WEATHER WILL CONTINUE FOR FRI AND SAT AS THE UPPER RIDGE
MOVES THROUGH THE REGION. HOWEVER...THE RIDGE WILL BE FLATTENED OUT
SOMEWHAT BY A LOW MOVING IN TO THE NORTH OVER B.C. A WEAK SHORTWAVE
ASSOCIATED WITH THE LOW MAY MOVE BRING SLIGHTLY MORE ONSHORE FLOW ON
FRI...BUT EXPECT MINIMAL IMPACT TO THE SENSIBLE WEATHER. TEMPS ON FRI
AND SAT SHOULD BE SIMILAR TO THU WITH INTERIOR HIGHS INTO THE LOW TO
MID 80S.

WILL CONTINUE TO KEEP A SLIGHT CHANCE OF THUNDER ALONG THE CASCADE
CREST EACH AFTERNOON AND EVENING FOR THE NEXT FEW DAYS...AS THE
MODELS CONTINUE TO ADVERTISE SOME LINGERING INSTABILITY. THE BEST
CHANCE APPEARS TO BE ON FRI AS THE WEAK UPPER LEVEL SHORTWAVE MOVES
THROUGH. PYLE

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEAK SHORTWAVE
RIDGING MOVES THROUGH THE AREA EARLY SAT NIGHT WITH AN APPROACHING
UPPER LEVEL LOW PRESSURE SYSTEM NEARING 130W BY EARLY SUN. AS THIS
LOW PRESSURE TRACKS INLAND...INCREASING CLOUDS AND MUCH COOLER
TEMPERATURES MOVE INTO THE REGION. SHOWERS WILL BEGIN BY LATE SUN
AFTERNOON OR EVENING AS THE SURFACE BOUNDARY SLIDES ONSHORE AND
ACROSS THE REGION...WITH A CHANCE FOR THUNDERSTORMS IN THE CASCADES
SOUTH OF AROUND MT HOOD. AS THIS UPPER LOW CONTINUES TO TRACK ALONG
A GENERALLY SOUTHWEST TO EAST-NORTHEAST PATH ACROSS THE REGION AND
THEN EAST OF THE CASCADES...EXPECT CONTINUED RAIN CHANCES AND COOLER
WEATHER TO CONTINUE THROUGH AROUND MIDWEEK. WHILE SOME MODEST
DIFFERENCES IN PATTERN EVOLUTION BETWEEN MODEL SOLUTIONS SUGGEST A
BIT OF UNCERTAINTY IN LOCATION AND TIMING OF RAINFALL AMOUNTS...THE
MODEL GUIDANCE REMAINS IN REMARKABLY DECENT AGREEMENT WITH RESPECT
TO THE SHOWERY PATTERN ALONG WITH TEMPERATURES AT OR A FEW DEGREES
BELOW SEASONAL NORMALS.
&&

.AVIATION...THE SUMMERTIME STRATUS PATTERN LOOKS TO CONTINUE FOR
THE NEXT SEVERAL DAYS. CIGS HAVE DROPPED MOSTLY TO IFR ALONG THE
COAST AND WILL CONTINUE THROUGH THE OVERNIGHT HOURS. VFR CIGS
PRESENT INLAND WITH CLEARING SKIES THIS EVENING. MVFR STRATUS
LOOKS TO PUSH INLAND THU MORNING WITH MORE SKY COVER IN THE NORTH
AND SOUTH VALLEY WITH LESS CHANCE OF CIGS AROUND SALEM.

KPDX AND APPROACHES...CLEAR SKIES THIS EVENING WITH SCT TO BKN CIG
AROUND 1000 FT DEVELOPING AFTER 09Z. CONFIDENCE IS LOW REGARDING
HOW MUCH MVFR SKY COVER THERE WILL BE. EITHER WAY...CONDITIONS
SHOULD RETURN TO VFR BY AROUND 18Z.

&&

.MARINE...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS. MILD
CONDITIONS CONTINUE THROUGH THE WEEKEND WITH HIGH PRES OFFSHORE
AND LOW PRES OVER THE INLAND PAC NW. EXPECT N TO NW WINDS TO
REMAIN GENERALLY BELOW SMALL CRAFT ADVISORY CRITERIA.
HOWEVER...BRIEF PERIODS OF ISOLATED GUSTS ABOVE 21 KT ARE POSSIBLE
SOUTH OF NEWPORT IN THE EVENING. MIXED SEAS BETWEEN 5 AND 7 FT
WILL CONTINUE THROUGH THE WEEKEND AND COULD BECOME CHOPPY AT TIMES
DUE TO THE FRESH NW SWELL BEING GENERATED OFF OF BC. THE SW SWELL
IS EXPECTED TO BECOME THE DOMINATE SWELL ON FRI. /64

&&

.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 280343 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
837 PM PDT WED MAY 27 2015


.SYNOPSIS...THE UPPER LEVEL CLOSED LOW THAT HAS BEEN OVER THE PAC NW
FOR THE PAST FEW DAYS IS NOW CENTERED OVER WRN IDAHO. THE LOW WILL
CONTINUE TO PUSH GRADUALLY EASTWARD INTO THE NRN ROCKIES TONIGHT AND
THU. AN UPPER LEVEL RIDGE WILL BUILD IN BEHIND...BRINGING A WARMER
AND DRIER AIR MASS FOR THE REST OF THE WEEK AND MUCH OF THE WEEKEND.
ANOTHER UPPER LEVEL LOW WILL APPROACH FROM THE SW LATE LATE SUN INTO
MON...BRINGING COOLER TEMPS AND A THREAT FOR SHOWERS AND
THUNDERSTORMS FOR EARLY NEXT WEEK.

&&

.UPDATE...SOME THUNDERSTORMS FIRED UP OVER THE SOUTH WA CASCADES
THIS AFTERNOON AND EARLY EVENING...BUT IS NOW ON THE DECREASE.WHILE
THE LOW IS FURTHER INLAND THAN TUE A SHORTWAVE DROPPED INTO EASTERN
WA THIS AFTERNOON BRINING MORE NORTHERLY FLOW ALOFT COMPARED TO THE
NWLY FLOW TUE. MODEL SOUNDINGS IN THE AREA OF CONVECTION OVER
SKAMANIA COUNTY SHOWED THIN CAPE ABOVE THE MOIST LAYER AROUND 850 MB.
  MARGINAL INSTABILITY RETURNS OVER THE CASCADES THU AFTERNOON AND
EARLY EVENING. MOISTURE WILL BE MORE LIMITED THAN TODAY AND THE WEST
TO NORTHWEST WIND ALOFT SHOULD LIMIT CONVECTION NEAR AND EAST OF THE
CASCADE CREST.

A MILD EVENING WITH MOSTLY CLEAR SKIES AND TEMPERATURES IN THE UPPER
60S TO MID 70S INLAND. THE MARINE LAYER IS WORKING ITS WAY ONSHORE
WITH CLOUDY SKIES AT THE COAST AND TEMPERATURES DOWN INTO THE MID
50S.  SHOULD SEE STRATUS SEEP INLAND OVERNIGHT INTO THU
MORNING...PARTICULARLY ON THE LOWER COLUMBIA RIVER TO THE PORTLAND
AREA AND SOME IN THE  SOUTH WILLAMETTE VALLEY. HOWEVER WITH THE
SHALLOWER MARINE LAYER THERE WILL BE MORE SUNSHINE TOMORROW.
/26

PREVIOUS SHORT TERM DISCUSSION FOLLOWS...
SHORT TERM TONIGHT THROUGH SATURDAY...THE PERSISTENT CLOSED UPPER
LEVEL LOW THAT HAS BEEN OVER THE PAC NW FOR THE PAST SEVERAL DAYS IS
NOW CENTERED OVER WRN IDAHO THIS AFTERNOON. SIMILAR TO
YESTERDAY...AFTERNOON SHOWERS AND THUNDERSTORMS ARE DEVELOPING UNDER
THE COLD LOW OVER ERN WASHINGTON AND OREGON. A FEW SHOWERS ARE
DEVELOPING ALONG THE E SLOPES OF THE SOUTH WASHINGTON CASCADES...SO
WILL CONTINUE TO KEEP A SLIGHT CHANCE OF THUNDER ALONG THE CREST
THROUGH EARLY THIS EVENING. HOWEVER...MOST OF THE ACTIVITY SHOULD
AGAIN REMAIN EAST OF THE CREST. OTHERWISE...A VERY NICE DAY IS
UNDERWAY ACROSS THE FCST AREA. THE THINNER MARINE STRATUS LAYER TODAY
BURNED OFF QUITE A BIT SOONER THAN WE SAW THE PAST COUPLE OF
DAYS...ALTHOUGH SOME STRATOCUMULUS HAVE FORMED OVER THE PAST COUPLE
OF HOURS DUE TO DAYTIME LOW LEVEL MIXING. EXPECT AFTERNOON HIGHS TO
REACH INTO THE MID TO UPPER 70S FOR MOST EVERYONE IN THE INTERIOR
LOWLANDS...WHILE THE COAST WILL REMAIN IN THE 60S WITH NORTHWESTERLY
ONSHORE FLOW.

THE UPPER LOW WILL DRIFT FURTHER EAST TONIGHT AND THU. THIS WILL
ALLOW AN UPPER LEVEL RIDGE TO PUSH TOWARD THE PAC NW...BRINGING A
GRADUALLY WARMER AND DRIER AIR MASS TO THE REGION. EXPECT THE MARINE
STRATUS TO PUSH TO BE EVEN WEAKER TONIGHT...WITH THE MAJORITY OF
INLAND VALLEY LOCATIONS REMAINING CLOUD FREE. 850 MB TEMPS ARE
EXPECTED TO INCREASE TO 13 TO 15 C TOMORROW...WHICH SHOULD RESULT IN
AFTER HIGHS REACHING INTO THE 80S FOR MOST OF THE INTERIOR LOWLANDS.
THE COAST WILL AGAIN STAY COOLER WITH THE NW LOW LEVEL FLOW.

THE WARM WEATHER WILL CONTINUE FOR FRI AND SAT AS THE UPPER RIDGE
MOVES THROUGH THE REGION. HOWEVER...THE RIDGE WILL BE FLATTENED OUT
SOMEWHAT BY A LOW MOVING IN TO THE NORTH OVER B.C. A WEAK SHORTWAVE
ASSOCIATED WITH THE LOW MAY MOVE BRING SLIGHTLY MORE ONSHORE FLOW ON
FRI...BUT EXPECT MINIMAL IMPACT TO THE SENSIBLE WEATHER. TEMPS ON FRI
AND SAT SHOULD BE SIMILAR TO THU WITH INTERIOR HIGHS INTO THE LOW TO
MID 80S.

WILL CONTINUE TO KEEP A SLIGHT CHANCE OF THUNDER ALONG THE CASCADE
CREST EACH AFTERNOON AND EVENING FOR THE NEXT FEW DAYS...AS THE
MODELS CONTINUE TO ADVERTISE SOME LINGERING INSTABILITY. THE BEST
CHANCE APPEARS TO BE ON FRI AS THE WEAK UPPER LEVEL SHORTWAVE MOVES
THROUGH. PYLE

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEAK SHORTWAVE
RIDGING MOVES THROUGH THE AREA EARLY SAT NIGHT WITH AN APPROACHING
UPPER LEVEL LOW PRESSURE SYSTEM NEARING 130W BY EARLY SUN. AS THIS
LOW PRESSURE TRACKS INLAND...INCREASING CLOUDS AND MUCH COOLER
TEMPERATURES MOVE INTO THE REGION. SHOWERS WILL BEGIN BY LATE SUN
AFTERNOON OR EVENING AS THE SURFACE BOUNDARY SLIDES ONSHORE AND
ACROSS THE REGION...WITH A CHANCE FOR THUNDERSTORMS IN THE CASCADES
SOUTH OF AROUND MT HOOD. AS THIS UPPER LOW CONTINUES TO TRACK ALONG
A GENERALLY SOUTHWEST TO EAST-NORTHEAST PATH ACROSS THE REGION AND
THEN EAST OF THE CASCADES...EXPECT CONTINUED RAIN CHANCES AND COOLER
WEATHER TO CONTINUE THROUGH AROUND MIDWEEK. WHILE SOME MODEST
DIFFERENCES IN PATTERN EVOLUTION BETWEEN MODEL SOLUTIONS SUGGEST A
BIT OF UNCERTAINTY IN LOCATION AND TIMING OF RAINFALL AMOUNTS...THE
MODEL GUIDANCE REMAINS IN REMARKABLY DECENT AGREEMENT WITH RESPECT
TO THE SHOWERY PATTERN ALONG WITH TEMPERATURES AT OR A FEW DEGREES
BELOW SEASONAL NORMALS.
&&

.AVIATION...THE SUMMERTIME STRATUS PATTERN LOOKS TO CONTINUE FOR
THE NEXT SEVERAL DAYS. CIGS HAVE DROPPED MOSTLY TO IFR ALONG THE
COAST AND WILL CONTINUE THROUGH THE OVERNIGHT HOURS. VFR CIGS
PRESENT INLAND WITH CLEARING SKIES THIS EVENING. MVFR STRATUS
LOOKS TO PUSH INLAND THU MORNING WITH MORE SKY COVER IN THE NORTH
AND SOUTH VALLEY WITH LESS CHANCE OF CIGS AROUND SALEM.

KPDX AND APPROACHES...CLEAR SKIES THIS EVENING WITH SCT TO BKN CIG
AROUND 1000 FT DEVELOPING AFTER 09Z. CONFIDENCE IS LOW REGARDING
HOW MUCH MVFR SKY COVER THERE WILL BE. EITHER WAY...CONDITIONS
SHOULD RETURN TO VFR BY AROUND 18Z.

&&

.MARINE...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS. MILD
CONDITIONS CONTINUE THROUGH THE WEEKEND WITH HIGH PRES OFFSHORE
AND LOW PRES OVER THE INLAND PAC NW. EXPECT N TO NW WINDS TO
REMAIN GENERALLY BELOW SMALL CRAFT ADVISORY CRITERIA.
HOWEVER...BRIEF PERIODS OF ISOLATED GUSTS ABOVE 21 KT ARE POSSIBLE
SOUTH OF NEWPORT IN THE EVENING. MIXED SEAS BETWEEN 5 AND 7 FT
WILL CONTINUE THROUGH THE WEEKEND AND COULD BECOME CHOPPY AT TIMES
DUE TO THE FRESH NW SWELL BEING GENERATED OFF OF BC. THE SW SWELL
IS EXPECTED TO BECOME THE DOMINATE SWELL ON FRI. /64

&&

.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 280343 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
837 PM PDT WED MAY 27 2015


.SYNOPSIS...THE UPPER LEVEL CLOSED LOW THAT HAS BEEN OVER THE PAC NW
FOR THE PAST FEW DAYS IS NOW CENTERED OVER WRN IDAHO. THE LOW WILL
CONTINUE TO PUSH GRADUALLY EASTWARD INTO THE NRN ROCKIES TONIGHT AND
THU. AN UPPER LEVEL RIDGE WILL BUILD IN BEHIND...BRINGING A WARMER
AND DRIER AIR MASS FOR THE REST OF THE WEEK AND MUCH OF THE WEEKEND.
ANOTHER UPPER LEVEL LOW WILL APPROACH FROM THE SW LATE LATE SUN INTO
MON...BRINGING COOLER TEMPS AND A THREAT FOR SHOWERS AND
THUNDERSTORMS FOR EARLY NEXT WEEK.

&&

.UPDATE...SOME THUNDERSTORMS FIRED UP OVER THE SOUTH WA CASCADES
THIS AFTERNOON AND EARLY EVENING...BUT IS NOW ON THE DECREASE.WHILE
THE LOW IS FURTHER INLAND THAN TUE A SHORTWAVE DROPPED INTO EASTERN
WA THIS AFTERNOON BRINING MORE NORTHERLY FLOW ALOFT COMPARED TO THE
NWLY FLOW TUE. MODEL SOUNDINGS IN THE AREA OF CONVECTION OVER
SKAMANIA COUNTY SHOWED THIN CAPE ABOVE THE MOIST LAYER AROUND 850 MB.
  MARGINAL INSTABILITY RETURNS OVER THE CASCADES THU AFTERNOON AND
EARLY EVENING. MOISTURE WILL BE MORE LIMITED THAN TODAY AND THE WEST
TO NORTHWEST WIND ALOFT SHOULD LIMIT CONVECTION NEAR AND EAST OF THE
CASCADE CREST.

A MILD EVENING WITH MOSTLY CLEAR SKIES AND TEMPERATURES IN THE UPPER
60S TO MID 70S INLAND. THE MARINE LAYER IS WORKING ITS WAY ONSHORE
WITH CLOUDY SKIES AT THE COAST AND TEMPERATURES DOWN INTO THE MID
50S.  SHOULD SEE STRATUS SEEP INLAND OVERNIGHT INTO THU
MORNING...PARTICULARLY ON THE LOWER COLUMBIA RIVER TO THE PORTLAND
AREA AND SOME IN THE  SOUTH WILLAMETTE VALLEY. HOWEVER WITH THE
SHALLOWER MARINE LAYER THERE WILL BE MORE SUNSHINE TOMORROW.
/26

PREVIOUS SHORT TERM DISCUSSION FOLLOWS...
SHORT TERM TONIGHT THROUGH SATURDAY...THE PERSISTENT CLOSED UPPER
LEVEL LOW THAT HAS BEEN OVER THE PAC NW FOR THE PAST SEVERAL DAYS IS
NOW CENTERED OVER WRN IDAHO THIS AFTERNOON. SIMILAR TO
YESTERDAY...AFTERNOON SHOWERS AND THUNDERSTORMS ARE DEVELOPING UNDER
THE COLD LOW OVER ERN WASHINGTON AND OREGON. A FEW SHOWERS ARE
DEVELOPING ALONG THE E SLOPES OF THE SOUTH WASHINGTON CASCADES...SO
WILL CONTINUE TO KEEP A SLIGHT CHANCE OF THUNDER ALONG THE CREST
THROUGH EARLY THIS EVENING. HOWEVER...MOST OF THE ACTIVITY SHOULD
AGAIN REMAIN EAST OF THE CREST. OTHERWISE...A VERY NICE DAY IS
UNDERWAY ACROSS THE FCST AREA. THE THINNER MARINE STRATUS LAYER TODAY
BURNED OFF QUITE A BIT SOONER THAN WE SAW THE PAST COUPLE OF
DAYS...ALTHOUGH SOME STRATOCUMULUS HAVE FORMED OVER THE PAST COUPLE
OF HOURS DUE TO DAYTIME LOW LEVEL MIXING. EXPECT AFTERNOON HIGHS TO
REACH INTO THE MID TO UPPER 70S FOR MOST EVERYONE IN THE INTERIOR
LOWLANDS...WHILE THE COAST WILL REMAIN IN THE 60S WITH NORTHWESTERLY
ONSHORE FLOW.

THE UPPER LOW WILL DRIFT FURTHER EAST TONIGHT AND THU. THIS WILL
ALLOW AN UPPER LEVEL RIDGE TO PUSH TOWARD THE PAC NW...BRINGING A
GRADUALLY WARMER AND DRIER AIR MASS TO THE REGION. EXPECT THE MARINE
STRATUS TO PUSH TO BE EVEN WEAKER TONIGHT...WITH THE MAJORITY OF
INLAND VALLEY LOCATIONS REMAINING CLOUD FREE. 850 MB TEMPS ARE
EXPECTED TO INCREASE TO 13 TO 15 C TOMORROW...WHICH SHOULD RESULT IN
AFTER HIGHS REACHING INTO THE 80S FOR MOST OF THE INTERIOR LOWLANDS.
THE COAST WILL AGAIN STAY COOLER WITH THE NW LOW LEVEL FLOW.

THE WARM WEATHER WILL CONTINUE FOR FRI AND SAT AS THE UPPER RIDGE
MOVES THROUGH THE REGION. HOWEVER...THE RIDGE WILL BE FLATTENED OUT
SOMEWHAT BY A LOW MOVING IN TO THE NORTH OVER B.C. A WEAK SHORTWAVE
ASSOCIATED WITH THE LOW MAY MOVE BRING SLIGHTLY MORE ONSHORE FLOW ON
FRI...BUT EXPECT MINIMAL IMPACT TO THE SENSIBLE WEATHER. TEMPS ON FRI
AND SAT SHOULD BE SIMILAR TO THU WITH INTERIOR HIGHS INTO THE LOW TO
MID 80S.

WILL CONTINUE TO KEEP A SLIGHT CHANCE OF THUNDER ALONG THE CASCADE
CREST EACH AFTERNOON AND EVENING FOR THE NEXT FEW DAYS...AS THE
MODELS CONTINUE TO ADVERTISE SOME LINGERING INSTABILITY. THE BEST
CHANCE APPEARS TO BE ON FRI AS THE WEAK UPPER LEVEL SHORTWAVE MOVES
THROUGH. PYLE

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEAK SHORTWAVE
RIDGING MOVES THROUGH THE AREA EARLY SAT NIGHT WITH AN APPROACHING
UPPER LEVEL LOW PRESSURE SYSTEM NEARING 130W BY EARLY SUN. AS THIS
LOW PRESSURE TRACKS INLAND...INCREASING CLOUDS AND MUCH COOLER
TEMPERATURES MOVE INTO THE REGION. SHOWERS WILL BEGIN BY LATE SUN
AFTERNOON OR EVENING AS THE SURFACE BOUNDARY SLIDES ONSHORE AND
ACROSS THE REGION...WITH A CHANCE FOR THUNDERSTORMS IN THE CASCADES
SOUTH OF AROUND MT HOOD. AS THIS UPPER LOW CONTINUES TO TRACK ALONG
A GENERALLY SOUTHWEST TO EAST-NORTHEAST PATH ACROSS THE REGION AND
THEN EAST OF THE CASCADES...EXPECT CONTINUED RAIN CHANCES AND COOLER
WEATHER TO CONTINUE THROUGH AROUND MIDWEEK. WHILE SOME MODEST
DIFFERENCES IN PATTERN EVOLUTION BETWEEN MODEL SOLUTIONS SUGGEST A
BIT OF UNCERTAINTY IN LOCATION AND TIMING OF RAINFALL AMOUNTS...THE
MODEL GUIDANCE REMAINS IN REMARKABLY DECENT AGREEMENT WITH RESPECT
TO THE SHOWERY PATTERN ALONG WITH TEMPERATURES AT OR A FEW DEGREES
BELOW SEASONAL NORMALS.
&&

.AVIATION...THE SUMMERTIME STRATUS PATTERN LOOKS TO CONTINUE FOR
THE NEXT SEVERAL DAYS. CIGS HAVE DROPPED MOSTLY TO IFR ALONG THE
COAST AND WILL CONTINUE THROUGH THE OVERNIGHT HOURS. VFR CIGS
PRESENT INLAND WITH CLEARING SKIES THIS EVENING. MVFR STRATUS
LOOKS TO PUSH INLAND THU MORNING WITH MORE SKY COVER IN THE NORTH
AND SOUTH VALLEY WITH LESS CHANCE OF CIGS AROUND SALEM.

KPDX AND APPROACHES...CLEAR SKIES THIS EVENING WITH SCT TO BKN CIG
AROUND 1000 FT DEVELOPING AFTER 09Z. CONFIDENCE IS LOW REGARDING
HOW MUCH MVFR SKY COVER THERE WILL BE. EITHER WAY...CONDITIONS
SHOULD RETURN TO VFR BY AROUND 18Z.

&&

.MARINE...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS. MILD
CONDITIONS CONTINUE THROUGH THE WEEKEND WITH HIGH PRES OFFSHORE
AND LOW PRES OVER THE INLAND PAC NW. EXPECT N TO NW WINDS TO
REMAIN GENERALLY BELOW SMALL CRAFT ADVISORY CRITERIA.
HOWEVER...BRIEF PERIODS OF ISOLATED GUSTS ABOVE 21 KT ARE POSSIBLE
SOUTH OF NEWPORT IN THE EVENING. MIXED SEAS BETWEEN 5 AND 7 FT
WILL CONTINUE THROUGH THE WEEKEND AND COULD BECOME CHOPPY AT TIMES
DUE TO THE FRESH NW SWELL BEING GENERATED OFF OF BC. THE SW SWELL
IS EXPECTED TO BECOME THE DOMINATE SWELL ON FRI. /64

&&

.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 272158 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
258 PM PDT WED MAY 27 2015


.SYNOPSIS...THE UPPER LEVEL CLOSED LOW THAT HAS BEEN OVER THE PAC NW
FOR THE PAST FEW DAYS IS NOW CENTERED OVER WRN IDAHO. THE LOW WILL
CONTINUE TO PUSH GRADUALLY EASTWARD INTO THE NRN ROCKIES TONIGHT AND
THU. AN UPPER LEVEL RIDGE WILL BUILD IN BEHIND...BRINGING A WARMER
AND DRIER AIR MASS FOR THE REST OF THE WEEK AND MUCH OF THE WEEKEND.
ANOTHER UPPER LEVEL LOW WILL APPROACH FROM THE SW LATE LATE SUN INTO
MON...BRINGING COOLER TEMPS AND A THREAT FOR SHOWERS AND
THUNDERSTORMS FOR EARLY NEXT WEEK.

&&

.SHORT TERM...TONIGHT THROUGH SATURDAY...THE PERSISTENT CLOSED UPPER
LEVEL LOW THAT HAS BEEN OVER THE PAC NW FOR THE PAST SEVERAL DAYS IS
NOW CENTERED OVER WRN IDAHO THIS AFTERNOON. SIMILAR TO
YESTERDAY...AFTERNOON SHOWERS AND THUNDERSTORMS ARE DEVELOPING UNDER
THE COLD LOW OVER ERN WASHINGTON AND OREGON. A FEW SHOWERS ARE
DEVELOPING ALONG THE E SLOPES OF THE SOUTH WASHINGTON CASCADES...SO
WILL CONTINUE TO KEEP A SLIGHT CHANCE OF THUNDER ALONG THE CREST
THROUGH EARLY THIS EVENING. HOWEVER...MOST OF THE ACTIVITY SHOULD
AGAIN REMAIN EAST OF THE CREST. OTHERWISE...A VERY NICE DAY IS
UNDERWAY ACROSS THE FCST AREA. THE THINNER MARINE STRATUS LAYER TODAY
BURNED OFF QUITE A BIT SOONER THAN WE SAW THE PAST COUPLE OF
DAYS...ALTHOUGH SOME STRATOCUMULUS HAVE FORMED OVER THE PAST COUPLE
OF HOURS DUE TO DAYTIME LOW LEVEL MIXING. EXPECT AFTERNOON HIGHS TO
REACH INTO THE MID TO UPPER 70S FOR MOST EVERYONE IN THE INTERIOR
LOWLANDS...WHILE THE COAST WILL REMAIN IN THE 60S WITH NORTHWESTERLY
ONSHORE FLOW.

THE UPPER LOW WILL DRIFT FURTHER EAST TONIGHT AND THU. THIS WILL
ALLOW AN UPPER LEVEL RIDGE TO PUSH TOWARD THE PAC NW...BRINGING A
GRADUALLY WARMER AND DRIER AIR MASS TO THE REGION. EXPECT THE MARINE
STRATUS TO PUSH TO BE EVEN WEAKER TONIGHT...WITH THE MAJORITY OF
INLAND VALLEY LOCATIONS REMAINING CLOUD FREE. 850 MB TEMPS ARE
EXPECTED TO INCREASE TO 13 TO 15 C TOMORROW...WHICH SHOULD RESULT IN
AFTER HIGHS REACHING INTO THE 80S FOR MOST OF THE INTERIOR LOWLANDS.
THE COAST WILL AGAIN STAY COOLER WITH THE NW LOW LEVEL FLOW.

THE WARM WEATHER WILL CONTINUE FOR FRI AND SAT AS THE UPPER RIDGE
MOVES THROUGH THE REGION. HOWEVER...THE RIDGE WILL BE FLATTENED OUT
SOMEWHAT BY A LOW MOVING IN TO THE NORTH OVER B.C. A WEAK SHORTWAVE
ASSOCIATED WITH THE LOW MAY MOVE BRING SLIGHTLY MORE ONSHORE FLOW ON
FRI...BUT EXPECT MINIMAL IMPACT TO THE SENSIBLE WEATHER. TEMPS ON FRI
AND SAT SHOULD BE SIMILAR TO THU WITH INTERIOR HIGHS INTO THE LOW TO
MID 80S.

WILL CONTINUE TO KEEP A SLIGHT CHANCE OF THUNDER ALONG THE CASCADE
CREST EACH AFTERNOON AND EVENING FOR THE NEXT FEW DAYS...AS THE
MODELS CONTINUE TO ADVERTISE SOME LINGERING INSTABILITY. THE BEST
CHANCE APPEARS TO BE ON FRI AS THE WEAK UPPER LEVEL SHORTWAVE MOVES
THROUGH. PYLE

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEAK SHORTWAVE
RIDGING MOVES THROUGH THE AREA EARLY SAT NIGHT WITH AN APPROACHING
UPPER LEVEL LOW PRESSURE SYSTEM NEARING 130W BY EARLY SUN. AS THIS
LOW PRESSURE TRACKS INLAND...INCREASING CLOUDS AND MUCH COOLER
TEMPERATURES MOVE INTO THE REGION. SHOWERS WILL BEGIN BY LATE SUN
AFTERNOON OR EVENING AS THE SURFACE BOUNDARY SLIDES ONSHORE AND
ACROSS THE REGION...WITH A CHANCE FOR THUNDERSTORMS IN THE CASCADES
SOUTH OF AROUND MT HOOD. AS THIS UPPER LOW CONTINUES TO TRACK ALONG
A GENERALLY SOUTHWEST TO EAST-NORTHEAST PATH ACROSS THE REGION AND
THEN EAST OF THE CASCADES...EXPECT CONTINUED RAIN CHANCES AND COOLER
WEATHER TO CONTINUE THROUGH AROUND MIDWEEK. WHILE SOME MODEST
DIFFERENCES IN PATTERN EVOLUTION BETWEEN MODEL SOLUTIONS SUGGEST A
BIT OF UNCERTAINTY IN LOCATION AND TIMING OF RAINFALL AMOUNTS...THE
MODEL GUIDANCE REMAINS IN REMARKABLY DECENT AGREEMENT WITH RESPECT
TO THE SHOWERY PATTERN ALONG WITH TEMPERATURES AT OR A FEW DEGREES
BELOW SEASONAL NORMALS.
&&

.AVIATION...THE SUMMERTIME STRATUS PATTERN LOOKS TO CONTINUE FOR
THE NEXT SEVERAL DAYS. A MIXTURE OF CIGS CURRENTLY EXISTS ALONG
THE COAST. EXPECT THESE CIGS TO CONTINUE TO THIN AND LIFT THIS
AFTERNOON WITH MOSTLY VFR CIGS THROUGH AROUND 03Z. VFR CIGS
CONTINUE INLAND WITH SCATTERED CUMULUS DEVELOPING OVER THE HIGHER
TERRAIN. EXPECT VFR CONDITIONS TO CONTINUE INTO TONIGHT WITH
SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE ALONG THE CASCADES.
MVFR STRATUS LIKELY RETURNS TO THE COAST THIS EVENING...WITH IFR
CIGS AND VSBY POSSIBLE EARLY THU MORNING. MVFR STRATUS LOOKS TO
PUSH INLAND THU MORNING. CONDITIONS THU LOOK TO BE A CARBON COPY
OF TODAY.

KPDX AND APPROACHES...EXPECT VFR CONDITIONS WITH SCATTERED SHOWERS
AND THUNDERSTORMS POSSIBLE ALONG THE CASCADES THROUGH 04Z. MVFR
STRATUS LOOKS TO RETURN AFTER 14Z THU MORNING. /64

&&

.MARINE...MILD CONDITIONS CONTINUE THROUGH THE WEEKEND WITH HIGH
PRES OFFSHORE AND LOW PRES OVER THE INLAND PAC NW. EXPECT NW WINDS
TO REMAIN GENERALLY BELOW SMALL CRAFT ADVISORY CRITERIA.
HOWEVER...BRIEF PERIODS OF ISOLATED GUSTS ABOVE 21 KT ARE POSSIBLE
SOUTH OF NEWPORT IN THE AFTERNOON/EVENING. MIXED SEAS BETWEEN 5
AND 7 FT WILL CONTINUE THROUGH THE WEEKEND AND COULD BECOME CHOPPY
AT TIMES DUE TO THE FRESH NW SWELL BEING GENERATED OFF OF B.C. THE
SW SWELL IS EXPECTED TO BECOME THE DOMINATE SWELL ON FRI. /64

&&

.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 272158 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
258 PM PDT WED MAY 27 2015


.SYNOPSIS...THE UPPER LEVEL CLOSED LOW THAT HAS BEEN OVER THE PAC NW
FOR THE PAST FEW DAYS IS NOW CENTERED OVER WRN IDAHO. THE LOW WILL
CONTINUE TO PUSH GRADUALLY EASTWARD INTO THE NRN ROCKIES TONIGHT AND
THU. AN UPPER LEVEL RIDGE WILL BUILD IN BEHIND...BRINGING A WARMER
AND DRIER AIR MASS FOR THE REST OF THE WEEK AND MUCH OF THE WEEKEND.
ANOTHER UPPER LEVEL LOW WILL APPROACH FROM THE SW LATE LATE SUN INTO
MON...BRINGING COOLER TEMPS AND A THREAT FOR SHOWERS AND
THUNDERSTORMS FOR EARLY NEXT WEEK.

&&

.SHORT TERM...TONIGHT THROUGH SATURDAY...THE PERSISTENT CLOSED UPPER
LEVEL LOW THAT HAS BEEN OVER THE PAC NW FOR THE PAST SEVERAL DAYS IS
NOW CENTERED OVER WRN IDAHO THIS AFTERNOON. SIMILAR TO
YESTERDAY...AFTERNOON SHOWERS AND THUNDERSTORMS ARE DEVELOPING UNDER
THE COLD LOW OVER ERN WASHINGTON AND OREGON. A FEW SHOWERS ARE
DEVELOPING ALONG THE E SLOPES OF THE SOUTH WASHINGTON CASCADES...SO
WILL CONTINUE TO KEEP A SLIGHT CHANCE OF THUNDER ALONG THE CREST
THROUGH EARLY THIS EVENING. HOWEVER...MOST OF THE ACTIVITY SHOULD
AGAIN REMAIN EAST OF THE CREST. OTHERWISE...A VERY NICE DAY IS
UNDERWAY ACROSS THE FCST AREA. THE THINNER MARINE STRATUS LAYER TODAY
BURNED OFF QUITE A BIT SOONER THAN WE SAW THE PAST COUPLE OF
DAYS...ALTHOUGH SOME STRATOCUMULUS HAVE FORMED OVER THE PAST COUPLE
OF HOURS DUE TO DAYTIME LOW LEVEL MIXING. EXPECT AFTERNOON HIGHS TO
REACH INTO THE MID TO UPPER 70S FOR MOST EVERYONE IN THE INTERIOR
LOWLANDS...WHILE THE COAST WILL REMAIN IN THE 60S WITH NORTHWESTERLY
ONSHORE FLOW.

THE UPPER LOW WILL DRIFT FURTHER EAST TONIGHT AND THU. THIS WILL
ALLOW AN UPPER LEVEL RIDGE TO PUSH TOWARD THE PAC NW...BRINGING A
GRADUALLY WARMER AND DRIER AIR MASS TO THE REGION. EXPECT THE MARINE
STRATUS TO PUSH TO BE EVEN WEAKER TONIGHT...WITH THE MAJORITY OF
INLAND VALLEY LOCATIONS REMAINING CLOUD FREE. 850 MB TEMPS ARE
EXPECTED TO INCREASE TO 13 TO 15 C TOMORROW...WHICH SHOULD RESULT IN
AFTER HIGHS REACHING INTO THE 80S FOR MOST OF THE INTERIOR LOWLANDS.
THE COAST WILL AGAIN STAY COOLER WITH THE NW LOW LEVEL FLOW.

THE WARM WEATHER WILL CONTINUE FOR FRI AND SAT AS THE UPPER RIDGE
MOVES THROUGH THE REGION. HOWEVER...THE RIDGE WILL BE FLATTENED OUT
SOMEWHAT BY A LOW MOVING IN TO THE NORTH OVER B.C. A WEAK SHORTWAVE
ASSOCIATED WITH THE LOW MAY MOVE BRING SLIGHTLY MORE ONSHORE FLOW ON
FRI...BUT EXPECT MINIMAL IMPACT TO THE SENSIBLE WEATHER. TEMPS ON FRI
AND SAT SHOULD BE SIMILAR TO THU WITH INTERIOR HIGHS INTO THE LOW TO
MID 80S.

WILL CONTINUE TO KEEP A SLIGHT CHANCE OF THUNDER ALONG THE CASCADE
CREST EACH AFTERNOON AND EVENING FOR THE NEXT FEW DAYS...AS THE
MODELS CONTINUE TO ADVERTISE SOME LINGERING INSTABILITY. THE BEST
CHANCE APPEARS TO BE ON FRI AS THE WEAK UPPER LEVEL SHORTWAVE MOVES
THROUGH. PYLE

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...WEAK SHORTWAVE
RIDGING MOVES THROUGH THE AREA EARLY SAT NIGHT WITH AN APPROACHING
UPPER LEVEL LOW PRESSURE SYSTEM NEARING 130W BY EARLY SUN. AS THIS
LOW PRESSURE TRACKS INLAND...INCREASING CLOUDS AND MUCH COOLER
TEMPERATURES MOVE INTO THE REGION. SHOWERS WILL BEGIN BY LATE SUN
AFTERNOON OR EVENING AS THE SURFACE BOUNDARY SLIDES ONSHORE AND
ACROSS THE REGION...WITH A CHANCE FOR THUNDERSTORMS IN THE CASCADES
SOUTH OF AROUND MT HOOD. AS THIS UPPER LOW CONTINUES TO TRACK ALONG
A GENERALLY SOUTHWEST TO EAST-NORTHEAST PATH ACROSS THE REGION AND
THEN EAST OF THE CASCADES...EXPECT CONTINUED RAIN CHANCES AND COOLER
WEATHER TO CONTINUE THROUGH AROUND MIDWEEK. WHILE SOME MODEST
DIFFERENCES IN PATTERN EVOLUTION BETWEEN MODEL SOLUTIONS SUGGEST A
BIT OF UNCERTAINTY IN LOCATION AND TIMING OF RAINFALL AMOUNTS...THE
MODEL GUIDANCE REMAINS IN REMARKABLY DECENT AGREEMENT WITH RESPECT
TO THE SHOWERY PATTERN ALONG WITH TEMPERATURES AT OR A FEW DEGREES
BELOW SEASONAL NORMALS.
&&

.AVIATION...THE SUMMERTIME STRATUS PATTERN LOOKS TO CONTINUE FOR
THE NEXT SEVERAL DAYS. A MIXTURE OF CIGS CURRENTLY EXISTS ALONG
THE COAST. EXPECT THESE CIGS TO CONTINUE TO THIN AND LIFT THIS
AFTERNOON WITH MOSTLY VFR CIGS THROUGH AROUND 03Z. VFR CIGS
CONTINUE INLAND WITH SCATTERED CUMULUS DEVELOPING OVER THE HIGHER
TERRAIN. EXPECT VFR CONDITIONS TO CONTINUE INTO TONIGHT WITH
SCATTERED SHOWERS AND THUNDERSTORMS POSSIBLE ALONG THE CASCADES.
MVFR STRATUS LIKELY RETURNS TO THE COAST THIS EVENING...WITH IFR
CIGS AND VSBY POSSIBLE EARLY THU MORNING. MVFR STRATUS LOOKS TO
PUSH INLAND THU MORNING. CONDITIONS THU LOOK TO BE A CARBON COPY
OF TODAY.

KPDX AND APPROACHES...EXPECT VFR CONDITIONS WITH SCATTERED SHOWERS
AND THUNDERSTORMS POSSIBLE ALONG THE CASCADES THROUGH 04Z. MVFR
STRATUS LOOKS TO RETURN AFTER 14Z THU MORNING. /64

&&

.MARINE...MILD CONDITIONS CONTINUE THROUGH THE WEEKEND WITH HIGH
PRES OFFSHORE AND LOW PRES OVER THE INLAND PAC NW. EXPECT NW WINDS
TO REMAIN GENERALLY BELOW SMALL CRAFT ADVISORY CRITERIA.
HOWEVER...BRIEF PERIODS OF ISOLATED GUSTS ABOVE 21 KT ARE POSSIBLE
SOUTH OF NEWPORT IN THE AFTERNOON/EVENING. MIXED SEAS BETWEEN 5
AND 7 FT WILL CONTINUE THROUGH THE WEEKEND AND COULD BECOME CHOPPY
AT TIMES DUE TO THE FRESH NW SWELL BEING GENERATED OFF OF B.C. THE
SW SWELL IS EXPECTED TO BECOME THE DOMINATE SWELL ON FRI. /64

&&

.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 271636 RRA
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
936 AM PDT WED MAY 27 2015


.SYNOPSIS...PESKY UPPER LOW CENTERED OVER THE OR/WA/ID BORDER TODAY
WILL SLOWLY PUSH EAST INTO THE NRN ROCKIES LATER TODAY AND THU. THIS
WILL USHER IN A WARMER AND DRIER AIR MASS. ANOTHER UPPER LOW WILL
APPROACH LATER THIS WEEKEND...BRING INCREASING ONSHORE FLOW AND
CLOUDS WITH COOLER TEMPERATURES...AND A THREAT OF SHOWERS...FOR EARLY
NEXT WEEK.

&&

.MORNING UPDATE...BASED ON THE VISIBLE SATELLITE IMAGERY THIS
MORNING...CUT BACK THE FCST SKY COVER FOR THE LATE MORNING AND EARLY
AFTERNOON. THERE WAS A MARINE STRATUS PUSH...BUT IT WAS PRETTY WEAK
WITH CLOUDS PUSHING INTO THE COASTAL GAPS AND UP THE LOWER COLUMBIA
INTO THE PORTLAND/VANCOUVER METRO AREA. THERE HAS ALSO BEEN SOME
PATCHY FOG OBSERVED DOWN IN THE SOUTHERN WILLAMETTE VALLEY. GIVEN THE
SHALLOWER MARINE LAYER AND THE DECREASED CLOUD COVER TO START...IT
LOOKS LIKE MOST OF THE INTERIOR WILL HAVE FULL SUNSHINE FOR THE
AFTERNOON. SO HIGHS IN THE UPPER 70S FOR MOST LOCATIONS SEEMS LIKE A
GOOD BET. PYLE

.SHORT TERM...TONIGHT THROUGH FRIDAY...
THE PESKY PATTERN WITH THE SLOW MOVING UPPER LOW OVER THE NORTHERN
ROCKIES AND EASTERN WASHINGTON WILL SLOWLY PUSH ON TO THE EAST OVER
THE NEXT 24 HOURS. STILL HAVE ENOUGH MOISTURE ROTATING AROUND THE
BACKSIDE OF THE LOW THAT WITH THE AFTERNOON HEATING AND THE UPSLOPE
COMPONENT...WILL SEE A FEW SHOWERS AND MAYBE A THUNDERSTORMS POP OVER
THE SOUTH WASHINGTON CASCADES...AND PERHAPS A BIT FURTHER TO THE
SOUTH OVER THE FAR NORTH OREGON CASCADES. NOT ALL THAT CONFIDENT THAT
WILL SEE MUCH OF ANY SHOWERS TO SOUTH OF MT HOOD AS FLOW BECOMES LESS
FAVORABLE.  BUT WILL KEEP A 20 PERCENT CHANCE THERE WITH BEST THREAT
OVER THE SOUTH WASHINGTON CASCADES. ALL SHOWERS WILL END SOON AFTER
SUNSET THIS EVENING.

OTHERWISE...AFTER MORNING CLOUDS...SHOULD HAVE AN ABUNDANCE OF
SUNSHINE OVER MUCH OF THE REGION TODAY. COAST WILL BE LAST TO LOSE
THE CLOUDS. SHOULD GET INTO THE MID TO UPPER 70S FOR THE INTERIOR
LOWLANDS...BUT COAST WILL HOLD IN THE LOWER TO MID 60S.

ONSHORE FLOW WEAKENS FURTHER ON THU AND FRI...SO SUSPECT THAT THE
MARINE LAYER CLOUDS WILL BE CONFINED TO THE COASTAL AREAS.  THIS LACK
OF CLOUDS INLAND WILL ALLOW TEMPERATURES TO CLIMB INTO THE LOWER TO
MID 80S.  EVEN THOUGH THE UPPER LOW HAS PUSHED OFF TO THE EAST...WILL
STILL HAVE VERY WEAK INSTABILITY OVER AREAS TO EAST OF THE CASCADES
EXTENDING WESTWARD TO THE CASCADES CREST. SO WILL KEEP A VERY MINOR
THREAT OF A SHOWER OVER THE HIGH CASCADES IN THE AFTERNOON AND
EVENINGS.THAT SAID...MY CONFIDENCE IS RATHER LOW THAT WILL ANYTHING
OTHER THAN SOME SCRAWNY AFTERNOON CUMULUS.  ROCKEY.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...WEAK RIDGING OVER THE
PACNW FRIDAY NIGHT INTO SATURDAY IS PUSHED OFF TO THE EAST AS A
TROUGH OF LOW PRESSURE MOVES ONSHORE SUNDAY NIGHT. SATURDAY WILL BE
A LOT LIKE FRIDAY WITH CLOUDY SKIES EARLY CLEARING TO PARTLY CLOUDY
SKIES IN THE AFTERNOON. THERE WILL ALSO BE A SLIGHT CHANCE FOR SOME
AFTERNOON/EVENING SHOWERS OR THUNDERSTORMS NEAR THE CASCADE CREST.
WITH THE APPROACH OF THE LOW PRESSURE SYSTEM FROM THE
SOUTHWEST...EXPECT SKIES TO REMAIN MOSTLY CLOUDY TO PARTLY SUNNY ON
SUNDAY KEEPING TEMPERATURES A BIT COOLER...TOO. UNDER WESTERLY FLOW
MODELS STILL SUGGEST A SLIGHT CHANCE FOR SHOWERS OR THUNDERSTORMS IN
THE CASCADES SUNDAY AFTERNOON/EVENING. WHETHER THESE
SHOWERS/THUNDERSTORMS OCCUR WILL DEPEND ON HOW MUCH CLOUD COVER
CLEARS OUT OVER THE CASCADES BY THE AFTERNOON. SUNDAY NIGHT OR EARLY
MONDAY AS THE FRONT MOVES THROUGH ASSOCIATED WITH THE UPPER-LEVEL
LOW PRESSURE SYSTEM...MODELS SUGGEST SHOWERS WILL SPREAD ACROSS THE
AREA THROUGH THE DAY MONDAY. A CHANCE FOR SOME SCATTERED SHOWERS
BEHIND THE FRONT WILL CONTINUE THROUGH TUESDAY. -MCCOY

&&

.AVIATION...THE SUMMERTIME STRATUS PATTERN LOOKS TO CONTINUE FOR
THE NEXT SEVERAL DAYS. IFR/MVFR STRATUS WILL LINGER ALONG THE
COAST FOR THE NEXT SEVERAL HOURS. COASTAL STRATUS LOOKS TO CLEAR
THIS AFTERNOON BETWEEN 21-03Z. A DEVELOPING SEA BREEZE WILL ALLOW
STRATUS TO RETURN INLAND THIS EVENING WITH IFR/MVFR CONDITIONS
THROUGH THU MORNING. INLAND TERMINALS LOOK TO REMAIN MOSTLY VFR
TODAY WITH SCATTERED SHOWERS POSSIBLE ALONG THE CASCADES THIS
AFTERNOON. HOWEVER...THE METRO TERMINALS WILL CONTINUE TO SEE
IFR/MVFR STRATUS THROUGH AROUND 18Z BEFORE THE DECK SCATTERS OUT.
MVFR STRATUS LIKELY RETURNS INLAND THU MORNING. CONDITIONS THU
LOOK TO BE A CARBON COPY OF TODAY.

KPDX AND APPROACHES...IFR/MVFR STRATUS LOOKS TO SCATTER OUT AROUND
18Z. EXPECT VFR CONDITIONS THIS AFTERNOON WITH SCATTERED SHOWERS
AND THUNDERSTORMS POSSIBLE ALONG THE CASCADES BETWEEN 20-04Z. MVFR
STRATUS LIKELY RETURNS EARLY THU MORNING. /64

&&

.MARINE...NO SIGNIFICANT CHANGES. PREVIOUS DISCUSSION FOLLOWS...
BROKEN RECORD CONTINUES WITH FAIRLY BENIGN CONDITIONS THROUGH THE
WEEKEND. A PAIR OF DOMINANT SWELL TRAINS HAVE ARRIVED TO THE
WATERS AND WILL REMAIN IN SOME FORM FOR THE NEXT SEVERAL DAYS.
STILL HAVE SOME FRESH SWELL FROM NORTHWEST WINDS OFF THE WESTERN
BC COAST COMBINING WITH THE SWELLS TO PRODUCE SOMEWHAT CHOPPY
SEAS. COMBINED SEAS WILL HOVER BETWEEN 6 AND 7 FT THE NEXT COUPLE
DAYS BEFORE EASING TO AROUND 5 FT THROUGH THE WEEKEND. WINDS WILL
STAY FROM THE WEST OR NORTHWEST WITH ONLY BRIEF AND LOCALIZED
GUSTS PUSHING TO 20 KTS OVER THE FAR SOUTHERN EXTENT OF THE
CENTRAL OREGON WATERS. /JBONK

&&

.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 271153 AAA
AFDPQR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PORTLAND
453 AM PDT WED MAY 27 2015

UPDATED AVIATION FOR LOWER CLOUD DECKS THIS MORNING

.SYNOPSIS...PESKY UPPER LOW OVER NRN ROCKIES WILL SLOWLY PUSH
FURTHER EAST. THIS WILL USHER IN DRIER AIR MASS...WITH TEMPERATURES
GRADUALLY WARMING. ANOTHER UPPER LOW WILL APPROACH LATER THIS
WEEKEND...BRING INCREASING ONSHORE FLOW AND CLOUDS WITH COOLER
TEMPERATURES...AND A THREAT OF SHOWERS...FOR EARLY NEXT WEEK.
&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...
THE PESKY PATTERN WITH THE SLOW MOVING UPPER LOW OVER THE NORTHERN
ROCKIES AND EASTERN WASHINGTON WILL SLOWLY PUSH ON TO THE EAST OVER
THE NEXT 24 HOURS. STILL HAVE ENOUGH MOISTURE ROTATING AROUND THE
BACKSIDE OF THE LOW THAT WITH THE AFTERNOON HEATING AND THE UPSLOPE
COMPONENT...WILL SEE A FEW SHOWERS AND MAYBE A THUNDERSTORMS POP OVER
THE SOUTH WASHINGTON CASCADES...AND PERHAPS A BIT FURTHER TO THE
SOUTH OVER THE FAR NORTH OREGON CASCADES. NOT ALL THAT CONFIDENT THAT
WILL SEE MUCH OF ANY SHOWERS TO SOUTH OF MT HOOD AS FLOW BECOMES LESS
FAVORABLE.  BUT WILL KEEP A 20 PERCENT CHANCE THERE WITH BEST THREAT
OVER THE SOUTH WASHINGTON CASCADES. ALL SHOWERS WILL END SOON AFTER
SUNSET THIS EVENING.

OTHERWISE...AFTER MORNING CLOUDS...SHOULD HAVE AN ABUNDANCE OF
SUNSHINE OVER MUCH OF THE REGION TODAY. COAST WILL BE LAST TO LOSE
THE CLOUDS. SHOULD GET INTO THE MID TO UPPER 70S FOR THE INTERIOR
LOWLANDS...BUT COAST WILL HOLD IN THE LOWER TO MID 60S.

ONSHORE FLOW WEAKENS FURTHER ON THU AND FRI...SO SUSPECT THAT THE
MARINE LAYER CLOUDS WILL BE CONFINED TO THE COASTAL AREAS.  THIS LACK
OF CLOUDS INLAND WILL ALLOW TEMPERATURES TO CLIMB INTO THE LOWER TO
MID 80S.  EVEN THOUGH THE UPPER LOW HAS PUSHED OFF TO THE EAST...WILL
STILL HAVE VERY WEAK INSTABILITY OVER AREAS TO EAST OF THE CASCADES
EXTENDING WESTWARD TO THE CASCADES CREST. SO WILL KEEP A VERY MINOR
THREAT OF A SHOWER OVER THE HIGH CASCADES IN THE AFTERNOON AND
EVENINGS.THAT SAID...MY CONFIDENCE IS RATHER LOW THAT WILL ANYTHING
OTHER THAN SOME SCRAWNY AFTERNOON CUMULUS.  ROCKEY.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...WEAK RIDGING OVER THE
PACNW FRIDAY NIGHT INTO SATURDAY IS PUSHED OFF TO THE EAST AS A
TROUGH OF LOW PRESSURE MOVES ONSHORE SUNDAY NIGHT. SATURDAY WILL BE
A LOT LIKE FRIDAY WITH CLOUDY SKIES EARLY CLEARING TO PARTLY CLOUDY
SKIES IN THE AFTERNOON. THERE WILL ALSO BE A SLIGHT CHANCE FOR SOME
AFTERNOON/EVENING SHOWERS OR THUNDERSTORMS NEAR THE CASCADE CREST.
WITH THE APPROACH OF THE LOW PRESSURE SYSTEM FROM THE
SOUTHWEST...EXPECT SKIES TO REMAIN MOSTLY CLOUDY TO PARTLY SUNNY ON
SUNDAY KEEPING TEMPERATURES A BIT COOLER...TOO. UNDER WESTERLY FLOW
MODELS STILL SUGGEST A SLIGHT CHANCE FOR SHOWERS OR THUNDERSTORMS IN
THE CASCADES SUNDAY AFTERNOON/EVENING. WHETHER THESE
SHOWERS/THUNDERSTORMS OCCUR WILL DEPEND ON HOW MUCH CLOUD COVER
CLEARS OUT OVER THE CASCADES BY THE AFTERNOON. SUNDAY NIGHT OR EARLY
MONDAY AS THE FRONT MOVES THROUGH ASSOCIATED WITH THE UPPER-LEVEL
LOW PRESSURE SYSTEM...MODELS SUGGEST SHOWERS WILL SPREAD ACROSS THE
AREA THROUGH THE DAY MONDAY. A CHANCE FOR SOME SCATTERED SHOWERS
BEHIND THE FRONT WILL CONTINUE THROUGH TUESDAY. -MCCOY

&&

.AVIATION...HEADING INTO SOMEWHAT OF A SUMMERTIME STRATUS PATTERN
FOR THE NEXT COUPLE DAYS. HIGH END IFR/LOW END MVFR STRATUS WILL
LINGER NEAR THE COASTLINE WITH PERHAPS SEVERAL HOURS OF CLEARING
ROUGHLY 21-03Z BEFORE THE SEA BREEZE PULLS IT BACK OVER LAND FOR THE
LATE EVENING THROUGH THE MORNING. INLAND TERMINALS WILL ALSO LIKELY
SEE A HIGH END IFR/LOW END MVFR STRATUS DECK 008-015 AGL GENERALLY
DURING A 12Z TO 18Z PERIOD WITH OTHERWISE MAINLY SCT CLOUDS.
MODERATE CUMULUS AND SHOWERS POSSIBLE 18-04Z TODAY MAINLY NEAR THE
CASCADE CREST.

KPDX AND APPROACHES...IFR CIGS HAVE MOVED OVER THE FIELD AND WILL
REMAIN THROUGH AROUND 17Z OR SO AS THEY SHOULD BE FAIRLY THIN.
THEREAFTER...EXPECT SCATTERED SHALLOW CUMULUS MAINLY OVER THE
EASTERN APPROACHES AND THUNDERSTORMS POSSIBLE ALONG THE CASCADE
CREST AND EAST SLOPES. CLOUDS WILL DISSIPATE AROUND SUNSET. ANOTHER
SET OF LOW STRATUS PROBABLY WILL RETURN LATE OVERNIGHT. /JBONK

&&

.MARINE...BROKEN RECORD CONTINUES WITH FAIRLY BENIGN CONDITIONS
THROUGH THE WEEKEND. A PAIR OF DOMINANT SWELL TRAINS HAVE ARRIVED
TO THE WATERS AND WILL REMAIN IN SOME FORM FOR THE NEXT SEVERAL
DAYS. STILL HAVE SOME FRESH SWELL FROM NORTHWEST WINDS OFF THE
WESTERN BC COAST COMBINING WITH THE SWELLS TO PRODUCE SOMEWHAT
CHOPPY SEAS. COMBINED SEAS WILL HOVER BETWEEN 6 AND 7 FT THE NEXT
COUPLE DAYS BEFORE EASING TO AROUND 5 FT THROUGH THE WEEKEND.
WINDS WILL STAY FROM THE WEST OR NORTHWEST WITH ONLY BRIEF AND
LOCALIZED GUSTS PUSHING TO 20 KTS OVER THE FAR SOUTHERN EXTENT OF
THE CENTRAL OREGON WATERS. /JBONK
&&

.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 271153 AAA
AFDPQR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PORTLAND
453 AM PDT WED MAY 27 2015

UPDATED AVIATION FOR LOWER CLOUD DECKS THIS MORNING

.SYNOPSIS...PESKY UPPER LOW OVER NRN ROCKIES WILL SLOWLY PUSH
FURTHER EAST. THIS WILL USHER IN DRIER AIR MASS...WITH TEMPERATURES
GRADUALLY WARMING. ANOTHER UPPER LOW WILL APPROACH LATER THIS
WEEKEND...BRING INCREASING ONSHORE FLOW AND CLOUDS WITH COOLER
TEMPERATURES...AND A THREAT OF SHOWERS...FOR EARLY NEXT WEEK.
&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...
THE PESKY PATTERN WITH THE SLOW MOVING UPPER LOW OVER THE NORTHERN
ROCKIES AND EASTERN WASHINGTON WILL SLOWLY PUSH ON TO THE EAST OVER
THE NEXT 24 HOURS. STILL HAVE ENOUGH MOISTURE ROTATING AROUND THE
BACKSIDE OF THE LOW THAT WITH THE AFTERNOON HEATING AND THE UPSLOPE
COMPONENT...WILL SEE A FEW SHOWERS AND MAYBE A THUNDERSTORMS POP OVER
THE SOUTH WASHINGTON CASCADES...AND PERHAPS A BIT FURTHER TO THE
SOUTH OVER THE FAR NORTH OREGON CASCADES. NOT ALL THAT CONFIDENT THAT
WILL SEE MUCH OF ANY SHOWERS TO SOUTH OF MT HOOD AS FLOW BECOMES LESS
FAVORABLE.  BUT WILL KEEP A 20 PERCENT CHANCE THERE WITH BEST THREAT
OVER THE SOUTH WASHINGTON CASCADES. ALL SHOWERS WILL END SOON AFTER
SUNSET THIS EVENING.

OTHERWISE...AFTER MORNING CLOUDS...SHOULD HAVE AN ABUNDANCE OF
SUNSHINE OVER MUCH OF THE REGION TODAY. COAST WILL BE LAST TO LOSE
THE CLOUDS. SHOULD GET INTO THE MID TO UPPER 70S FOR THE INTERIOR
LOWLANDS...BUT COAST WILL HOLD IN THE LOWER TO MID 60S.

ONSHORE FLOW WEAKENS FURTHER ON THU AND FRI...SO SUSPECT THAT THE
MARINE LAYER CLOUDS WILL BE CONFINED TO THE COASTAL AREAS.  THIS LACK
OF CLOUDS INLAND WILL ALLOW TEMPERATURES TO CLIMB INTO THE LOWER TO
MID 80S.  EVEN THOUGH THE UPPER LOW HAS PUSHED OFF TO THE EAST...WILL
STILL HAVE VERY WEAK INSTABILITY OVER AREAS TO EAST OF THE CASCADES
EXTENDING WESTWARD TO THE CASCADES CREST. SO WILL KEEP A VERY MINOR
THREAT OF A SHOWER OVER THE HIGH CASCADES IN THE AFTERNOON AND
EVENINGS.THAT SAID...MY CONFIDENCE IS RATHER LOW THAT WILL ANYTHING
OTHER THAN SOME SCRAWNY AFTERNOON CUMULUS.  ROCKEY.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...WEAK RIDGING OVER THE
PACNW FRIDAY NIGHT INTO SATURDAY IS PUSHED OFF TO THE EAST AS A
TROUGH OF LOW PRESSURE MOVES ONSHORE SUNDAY NIGHT. SATURDAY WILL BE
A LOT LIKE FRIDAY WITH CLOUDY SKIES EARLY CLEARING TO PARTLY CLOUDY
SKIES IN THE AFTERNOON. THERE WILL ALSO BE A SLIGHT CHANCE FOR SOME
AFTERNOON/EVENING SHOWERS OR THUNDERSTORMS NEAR THE CASCADE CREST.
WITH THE APPROACH OF THE LOW PRESSURE SYSTEM FROM THE
SOUTHWEST...EXPECT SKIES TO REMAIN MOSTLY CLOUDY TO PARTLY SUNNY ON
SUNDAY KEEPING TEMPERATURES A BIT COOLER...TOO. UNDER WESTERLY FLOW
MODELS STILL SUGGEST A SLIGHT CHANCE FOR SHOWERS OR THUNDERSTORMS IN
THE CASCADES SUNDAY AFTERNOON/EVENING. WHETHER THESE
SHOWERS/THUNDERSTORMS OCCUR WILL DEPEND ON HOW MUCH CLOUD COVER
CLEARS OUT OVER THE CASCADES BY THE AFTERNOON. SUNDAY NIGHT OR EARLY
MONDAY AS THE FRONT MOVES THROUGH ASSOCIATED WITH THE UPPER-LEVEL
LOW PRESSURE SYSTEM...MODELS SUGGEST SHOWERS WILL SPREAD ACROSS THE
AREA THROUGH THE DAY MONDAY. A CHANCE FOR SOME SCATTERED SHOWERS
BEHIND THE FRONT WILL CONTINUE THROUGH TUESDAY. -MCCOY

&&

.AVIATION...HEADING INTO SOMEWHAT OF A SUMMERTIME STRATUS PATTERN
FOR THE NEXT COUPLE DAYS. HIGH END IFR/LOW END MVFR STRATUS WILL
LINGER NEAR THE COASTLINE WITH PERHAPS SEVERAL HOURS OF CLEARING
ROUGHLY 21-03Z BEFORE THE SEA BREEZE PULLS IT BACK OVER LAND FOR THE
LATE EVENING THROUGH THE MORNING. INLAND TERMINALS WILL ALSO LIKELY
SEE A HIGH END IFR/LOW END MVFR STRATUS DECK 008-015 AGL GENERALLY
DURING A 12Z TO 18Z PERIOD WITH OTHERWISE MAINLY SCT CLOUDS.
MODERATE CUMULUS AND SHOWERS POSSIBLE 18-04Z TODAY MAINLY NEAR THE
CASCADE CREST.

KPDX AND APPROACHES...IFR CIGS HAVE MOVED OVER THE FIELD AND WILL
REMAIN THROUGH AROUND 17Z OR SO AS THEY SHOULD BE FAIRLY THIN.
THEREAFTER...EXPECT SCATTERED SHALLOW CUMULUS MAINLY OVER THE
EASTERN APPROACHES AND THUNDERSTORMS POSSIBLE ALONG THE CASCADE
CREST AND EAST SLOPES. CLOUDS WILL DISSIPATE AROUND SUNSET. ANOTHER
SET OF LOW STRATUS PROBABLY WILL RETURN LATE OVERNIGHT. /JBONK

&&

.MARINE...BROKEN RECORD CONTINUES WITH FAIRLY BENIGN CONDITIONS
THROUGH THE WEEKEND. A PAIR OF DOMINANT SWELL TRAINS HAVE ARRIVED
TO THE WATERS AND WILL REMAIN IN SOME FORM FOR THE NEXT SEVERAL
DAYS. STILL HAVE SOME FRESH SWELL FROM NORTHWEST WINDS OFF THE
WESTERN BC COAST COMBINING WITH THE SWELLS TO PRODUCE SOMEWHAT
CHOPPY SEAS. COMBINED SEAS WILL HOVER BETWEEN 6 AND 7 FT THE NEXT
COUPLE DAYS BEFORE EASING TO AROUND 5 FT THROUGH THE WEEKEND.
WINDS WILL STAY FROM THE WEST OR NORTHWEST WITH ONLY BRIEF AND
LOCALIZED GUSTS PUSHING TO 20 KTS OVER THE FAR SOUTHERN EXTENT OF
THE CENTRAL OREGON WATERS. /JBONK
&&

.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 270946
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
245 AM PDT WED MAY 27 2015

.SYNOPSIS...PESKY UPPER LOW OVER NRN ROCKIES WILL SLOWLY PUSH
FURTHER EAST. THIS WILL USHER IN DRIER AIR MASS...WITH TEMPERATURES
GRADUALLY WARMING. ANOTHER UPPER LOW WILL APPROACH LATER THIS
WEEKEND...BRING INCREASING ONSHORE FLOW AND CLOUDS WITH COOLER
TEMPERATURES...AND A THREAT OF SHOWERS...FOR EARLY NEXT WEEK.
&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...
THE PESKY PATTERN WITH THE SLOW MOVING UPPER LOW OVER THE NORTHERN
ROCKIES AND EASTERN WASHINGTON WILL SLOWLY PUSH ON TO THE EAST OVER
THE NEXT 24 HOURS. STILL HAVE ENOUGH MOISTURE ROTATING AROUND THE
BACKSIDE OF THE LOW THAT WITH THE AFTERNOON HEATING AND THE UPSLOPE
COMPONENT...WILL SEE A FEW SHOWERS AND MAYBE A THUNDERSTORMS POP OVER
THE SOUTH WASHINGTON CASCADES...AND PERHAPS A BIT FURTHER TO THE
SOUTH OVER THE FAR NORTH OREGON CASCADES. NOT ALL THAT CONFIDENT THAT
WILL SEE MUCH OF ANY SHOWERS TO SOUTH OF MT HOOD AS FLOW BECOMES LESS
FAVORABLE.  BUT WILL KEEP A 20 PERCENT CHANCE THERE WITH BEST THREAT
OVER THE SOUTH WASHINGTON CASCADES. ALL SHOWERS WILL END SOON AFTER
SUNSET THIS EVENING.

OTHERWISE...AFTER MORNING CLOUDS...SHOULD HAVE AN ABUNDANCE OF
SUNSHINE OVER MUCH OF THE REGION TODAY. COAST WILL BE LAST TO LOSE
THE CLOUDS. SHOULD GET INTO THE MID TO UPPER 70S FOR THE INTERIOR
LOWLANDS...BUT COAST WILL HOLD IN THE LOWER TO MID 60S.

ONSHORE FLOW WEAKENS FURTHER ON THU AND FRI...SO SUSPECT THAT THE
MARINE LAYER CLOUDS WILL BE CONFINED TO THE COASTAL AREAS.  THIS LACK
OF CLOUDS INLAND WILL ALLOW TEMPERATURES TO CLIMB INTO THE LOWER TO
MID 80S.  EVEN THOUGH THE UPPER LOW HAS PUSHED OFF TO THE EAST...WILL
STILL HAVE VERY WEAK INSTABILITY OVER AREAS TO EAST OF THE CASCADES
EXTENDING WESTWARD TO THE CASCADES CREST. SO WILL KEEP A VERY MINOR
THREAT OF A SHOWER OVER THE HIGH CASCADES IN THE AFTERNOON AND
EVENINGS.THAT SAID...MY CONFIDENCE IS RATHER LOW THAT WILL ANYTHING
OTHER THAN SOME SCRAWNY AFTERNOON CUMULUS.  ROCKEY.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...WEAK RIDGING OVER THE
PACNW FRIDAY NIGHT INTO SATURDAY IS PUSHED OFF TO THE EAST AS A
TROUGH OF LOW PRESSURE MOVES ONSHORE SUNDAY NIGHT. SATURDAY WILL BE
A LOT LIKE FRIDAY WITH CLOUDY SKIES EARLY CLEARING TO PARTLY CLOUDY
SKIES IN THE AFTERNOON. THERE WILL ALSO BE A SLIGHT CHANCE FOR SOME
AFTERNOON/EVENING SHOWERS OR THUNDERSTORMS NEAR THE CASCADE CREST.
WITH THE APPROACH OF THE LOW PRESSURE SYSTEM FROM THE
SOUTHWEST...EXPECT SKIES TO REMAIN MOSTLY CLOUDY TO PARTLY SUNNY ON
SUNDAY KEEPING TEMPERATURES A BIT COOLER...TOO. UNDER WESTERLY FLOW
MODELS STILL SUGGEST A SLIGHT CHANCE FOR SHOWERS OR THUNDERSTORMS IN
THE CASCADES SUNDAY AFTERNOON/EVENING. WHETHER THESE
SHOWERS/THUNDERSTORMS OCCUR WILL DEPEND ON HOW MUCH CLOUD COVER
CLEARS OUT OVER THE CASCADES BY THE AFTERNOON. SUNDAY NIGHT OR EARLY
MONDAY AS THE FRONT MOVES THROUGH ASSOCIATED WITH THE UPPER-LEVEL
LOW PRESSURE SYSTEM...MODELS SUGGEST SHOWERS WILL SPREAD ACROSS THE
AREA THROUGH THE DAY MONDAY. A CHANCE FOR SOME SCATTERED SHOWERS
BEHIND THE FRONT WILL CONTINUE THROUGH TUESDAY. -MCCOY

&&

.AVIATION...HEADING INTO SOMEWHAT OF A SUMMERTIME STRATUS PATTERN
FOR THE NEXT COUPLE DAYS. HIGH END IFR/LOW END MVFR STRATUS WILL
LINGER NEAR THE COASTLINE WITH PERHAPS SEVERAL HOURS OF CLEARING
ROUGHLY 21-03Z BEFORE THE SEA BREEZE PULLS IT BACK OVER LAND FOR
THE LATE EVENING THROUGH THE MORNING. INLAND TERMINALS WILL LIKELY
SEE A LOWER END MVFR STRATUS DECK 010-015 AGL GENERALLY DURING A
12Z TO 18Z PERIOD WITH OTHERWISE MAINLY SCT CLOUDS. MODERATE
CUMULUS AND SHOWERS POSSIBLE 18-04Z TODAY MAINLY NEAR THE CASCADE
CREST.

KPDX AND APPROACHES...VFR CONDS THROUGH ABOUT 14Z WHEN CIGS AT
ROUGHLY 012 POSSIBLY DRIFT OVER THE FIELD FROM THE NORTHWEST. IF
SO...THEY SHOULD BE RELATIVELY SHALLOW AND BURN OFF BY 17Z OR SO.
EXPECT SCATTERED SHALLOW CUMULUS MAINLY OVER THE EASTERN
APPROACHES WITH THUNDERSTORMS POSSIBLE ALONG THE CASCADE CREST AND
EAST SLOPES. CLOUDS WILL DISSIPATE AROUND SUNSET. /JBONK
&&

.MARINE...BROKEN RECORD CONTINUES WITH FAIRLY BENIGN CONDITIONS
THROUGH THE WEEKEND. A PAIR OF DOMINANT SWELL TRAINS HAVE ARRIVED
TO THE WATERS AND WILL REMAIN IN SOME FORM FOR THE NEXT SEVERAL
DAYS. STILL HAVE SOME FRESH SWELL FROM NORTHWEST WINDS OFF THE
WESTERN BC COAST COMBINING WITH THE SWELLS TO PRODUCE SOMEWHAT
CHOPPY SEAS. COMBINED SEAS WILL HOVER BETWEEN 6 AND 7 FT THE NEXT
COUPLE DAYS BEFORE EASING TO AROUND 5 FT THROUGH THE WEEKEND.
WINDS WILL STAY FROM THE WEST OR NORTHWEST WITH ONLY BRIEF AND
LOCALIZED GUSTS PUSHING TO 20 KTS OVER THE FAR SOUTHERN EXTENT OF
THE CENTRAL OREGON WATERS. /JBONK
&&

.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 270343
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
842 PM PDT TUE MAY 26 2015

.SYNOPSIS...AN UPPER LEVEL LOW PRES SYSTEM CENTERED OVER EASTERN WA
WILL MOVE SLOWLY SE INTO IDAHO TONIGHT AND WED. THE LOW WILL THEN
MOVE OFF TO THE E AS A RIDGE OF HIGH PRES BUILDS INTO THE REGION FROM
OFF THE PACIFIC. LOW LEVEL ONSHORE FLOW WILL GRADUALLY WEAKEN DURING
THE COURSE OF THE WEEK...RESULTING IN PROGRESSIVELY FEWER CLOUDS AND
WARMING TEMPS HEADING INTO THE WEEKEND. UPPER LEVEL LOW PRES WILL
LIKELY BRING COOLER TEMPERATURES...MORE CLOUDS...AND INCREASING
SHOWERS LATE IN THE WEEKEND AND EARLY NEXT WEEK.
&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...EVENING UPDATE...HAVE HAD A
FEW CLOSE CALLS LATE THIS AFTERNOON AND EARLIER THIS EVENING WITH
ISOLATED THUNDERSTORMS TRYING TO SNEAK OVER THE SW WASHINGTON
CASCADES. MUCH OF THE ACTIVITY STAYED EAST OF THE CASCADES...BUT MOST
LIKELY SAW BRIEF HEAVY RAIN EARLIER THIS AFTERNOON. THE UPPER LEVEL
LOW CONTINUES TO SLOWLY ROTATE OVER FAR EASTERN WASHINGTON THIS
EVENING AND THROUGH TONIGHT...WITH THUNDERSTORMS DRIFTING FURTHER
AWAY FROM OUR FORECAST AREA BORDER. MARINE STRATUS DISSIPATED QUITE A
BIT TODAY...WITH MOST LOCATIONS SEEING SUN THROUGH EARLY THIS
EVENING. MARINE STRATUS HAS ALREADY RETURNED TO THE CENTRAL OREGON
COAST...AND WILL GRADUALLY SPREAD NORTH ALONG THE COAST AND THROUGH
THE COASTAL GAPS OVERNIGHT. THE REMAINDER OF THE FORECAST REMAINS
VALID.../27

THE CLOSED LOW WILL CONTINUE TO DRIFT EASTWARD INTO IDAHO TONIGHT AND
WED. THIS WILL ALLOW HEIGHTS TO GRADUALLY RISE AS AN UPPER LEVEL
RIDGE BEGINS TO PUSH TOWARD THE PAC NW. THE ONSHORE FLOW WILL WEAKEN
AS THE LOW LEVEL FLOW TURNS MORE NORTHERLY OVER THE NEXT COUPLE OF
DAYS. THE MARINE LAYER WILL ALSO BECOME INCREASINGLY SHALLOW AS THE
HIGH PRES BUILDS IN. SO EXPECT LESS AND LESS OVERNIGHT MARINE STRATUS
INTRUSION AS WE GET LATER IN THE WEEK. IT STILL LOOKS LIKE CLOUDS
WILL FILL IN OVER A GOOD PORTION OF THE VALLEY TONIGHT AND WED
MORNING...BUT THE CLOUDS WILL BE THINNER AND THINK THAT CLOUD BURN
OFF
WILL BE QUITE A BIT SOONER THAN WE HAVE SEEN OVER THE PAST COUPLE OF
DAYS. THE INLAND PUSH LOOKS EVEN WEAKER FOR THU AND FRI
MORNINGS...AND IT CURRENTLY LOOKS LIKE MANY VALLEY LOCATIONS WILL
REMAIN STRATUS FREE. THE COMBINATION OF DECREASING CLOUD COVER AND A
GRADUALLY WARMING AIR MASS WILL RESULT IN TEMPERATURES CLIMBING
THROUGH THE REST OF THE WEEK. HIGHS SHOULD REACH WELL INTO THE 70S ON
WED AND INTO THE LOW TO MID 80S THU AND FRI. NW FLOW SHOULD KEEP
TEMPS AT THE COAST CAPPED IN THE 60S.

WILL CONTINUE WITH A SLIGHT CHANCE OF THUNDERSTORMS ALONG THE CASCADE
CREST EACH AFTERNOON AND EVENING THROUGH THE END OF THE WEEK. IT
APPEARS THAT WRAP AROUND FLOW ON THE BACK SIDE OF THE DEPARTING LOW
WILL KEEP SOME WEAK INSTABILITY OVER THE CASCADES THROUGH THU. THE
MODELS CONTINUE TO INDICATE SOME WEAK INSTABILITY FRI AS WE DEVELOP
W/SW FLOW ALOFT. PYLE

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...WEAK RIDGING OVER THE
PACNW FRIDAY NIGHT INTO SATURDAY IS PUSHED OFF TO THE EAST AS A
TROUGH OF LOW PRESSURE MOVES ONSHORE SUNDAY NIGHT. SATURDAY WILL BE
A LOT LIKE FRIDAY WITH CLOUDY SKIES EARLY CLEARING TO PARTLY CLOUDY
SKIES IN THE AFTERNOON. THERE WILL ALSO BE A SLIGHT CHANCE FOR SOME
AFTERNOON/EVENING SHOWERS OR THUNDERSTORMS NEAR THE CASCADE CREST.
WITH THE APPROACH OF THE LOW PRESSURE SYSTEM FROM THE
SOUTHWEST...EXPECT SKIES TO REMAIN MOSTLY CLOUDY TO PARTLY SUNNY ON
SUNDAY KEEPING TEMPERATURES A BIT COOLER...TOO. UNDER WESTERLY FLOW
MODELS STILL SUGGEST A SLIGHT CHANCE FOR SHOWERS OR THUNDERSTORMS IN
THE CASCADES SUNDAY AFTERNOON/EVENING. WHETHER THESE
SHOWERS/THUNDERSTORMS OCCUR WILL DEPEND ON HOW MUCH CLOUD COVER
CLEARS OUT OVER THE CASCADES BY THE AFTERNOON. SUNDAY NIGHT OR EARLY
MONDAY AS THE FRONT MOVES THROUGH ASSOCIATED WITH THE UPPER-LEVEL
LOW PRESSURE SYSTEM...MODELS SUGGEST SHOWERS WILL SPREAD ACROSS THE
AREA THROUGH THE DAY MONDAY. A CHANCE FOR SOME SCATTERED SHOWERS
BEHIND THE FRONT WILL CONTINUE THROUGH TUESDAY. -MCCOY

&&

.AVIATION...MARINE CLOUDS WORKING ITS WAY BACK TO THE COAST THIS
EVENING WITH WIDESPREAD MVFR CIGS EXPECTED. STRATUS AROUND
5000-7000 FEET ACROSS WESTERN WASHINGTON ADVANCING INTO THE
INTERIOR OF NW OREGON. BKN TO OVC CIGS GENERALLY NORTH OF KUAO.
MODELS ALL SHOW ENOUGH LOW LEVEL RELATIVE HUMIDITY TO INDICATE
MORE MARINE CLOUDS OVER MUCH OF OUR AREA TONIGHT AND WEDNESDAY
MORNING...BUT SHOULD BE SHALLOWER THAN TODAY. SO CIGS WILL BE MORE
LIKELY MVFR EXCEPT FOR POSSIBLE IFR ALONG THE COAST AND POSSIBLY
NEAR KEUG. THE LOWER INVERSION SHOULD LEAD TO EARLIER CLEARING ON
WEDNESDAY...POSSIBLY BY NOON.

KPDX AND APPROACHES...VFR CONDITIONS WITH CIGS AROUND 5000 FEET
THROUGH ABOUT 12Z WED. THEN A LOWER LAYER SHOULD FORM PROVIDED
ENOUGH CLEARING FROM THE HIGHER LAYER. ANY MVFR CIGS THAT FORM IS
EXPECTED TO DISSIPATE IN THE 18Z TO 20Z WED TIME FRAME. /MH

&&

.MARINE...NOT MUCH IN THE WAY OF SIGNIFICANT CHANGES. WILL BEGIN
TO SEE A MORE DOMINANT PAIR OF SWELL TRAINS ARRIVE FROM WELL OFF
TO THE WEST AND THE DISTANT SOUTH. ADDITIONALLY STILL HAVE SOME
FRESH SWELL FROM WINDS OFF THE WESTERN BC COAST TO COMBINE AND
PRODUCE SOMEWHAT CHOPPY AND CONFUSED SEAS. ON THE UP SIDE...
DOMINANT SEAS WILL ONLY BRIEFLY COMBINE TO AROUND 7 FT MAXIMUM AT
TIMES OVER THE NEXT COUPLE DAYS AND THUS REMAIN BELOW SMALL CRAFT
CRITERIA. OVERALL WINDS WILL STAY FROM THE WEST NORTHWEST WITH
ONLY BRIEF AND LOCALIZED GUSTS PUSHING OVER 20 KTS OVER THE FAR
SOUTHERN EXTENT OF THE WATERS. /JBONK/PT

&&

.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 270343
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
842 PM PDT TUE MAY 26 2015

.SYNOPSIS...AN UPPER LEVEL LOW PRES SYSTEM CENTERED OVER EASTERN WA
WILL MOVE SLOWLY SE INTO IDAHO TONIGHT AND WED. THE LOW WILL THEN
MOVE OFF TO THE E AS A RIDGE OF HIGH PRES BUILDS INTO THE REGION FROM
OFF THE PACIFIC. LOW LEVEL ONSHORE FLOW WILL GRADUALLY WEAKEN DURING
THE COURSE OF THE WEEK...RESULTING IN PROGRESSIVELY FEWER CLOUDS AND
WARMING TEMPS HEADING INTO THE WEEKEND. UPPER LEVEL LOW PRES WILL
LIKELY BRING COOLER TEMPERATURES...MORE CLOUDS...AND INCREASING
SHOWERS LATE IN THE WEEKEND AND EARLY NEXT WEEK.
&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...EVENING UPDATE...HAVE HAD A
FEW CLOSE CALLS LATE THIS AFTERNOON AND EARLIER THIS EVENING WITH
ISOLATED THUNDERSTORMS TRYING TO SNEAK OVER THE SW WASHINGTON
CASCADES. MUCH OF THE ACTIVITY STAYED EAST OF THE CASCADES...BUT MOST
LIKELY SAW BRIEF HEAVY RAIN EARLIER THIS AFTERNOON. THE UPPER LEVEL
LOW CONTINUES TO SLOWLY ROTATE OVER FAR EASTERN WASHINGTON THIS
EVENING AND THROUGH TONIGHT...WITH THUNDERSTORMS DRIFTING FURTHER
AWAY FROM OUR FORECAST AREA BORDER. MARINE STRATUS DISSIPATED QUITE A
BIT TODAY...WITH MOST LOCATIONS SEEING SUN THROUGH EARLY THIS
EVENING. MARINE STRATUS HAS ALREADY RETURNED TO THE CENTRAL OREGON
COAST...AND WILL GRADUALLY SPREAD NORTH ALONG THE COAST AND THROUGH
THE COASTAL GAPS OVERNIGHT. THE REMAINDER OF THE FORECAST REMAINS
VALID.../27

THE CLOSED LOW WILL CONTINUE TO DRIFT EASTWARD INTO IDAHO TONIGHT AND
WED. THIS WILL ALLOW HEIGHTS TO GRADUALLY RISE AS AN UPPER LEVEL
RIDGE BEGINS TO PUSH TOWARD THE PAC NW. THE ONSHORE FLOW WILL WEAKEN
AS THE LOW LEVEL FLOW TURNS MORE NORTHERLY OVER THE NEXT COUPLE OF
DAYS. THE MARINE LAYER WILL ALSO BECOME INCREASINGLY SHALLOW AS THE
HIGH PRES BUILDS IN. SO EXPECT LESS AND LESS OVERNIGHT MARINE STRATUS
INTRUSION AS WE GET LATER IN THE WEEK. IT STILL LOOKS LIKE CLOUDS
WILL FILL IN OVER A GOOD PORTION OF THE VALLEY TONIGHT AND WED
MORNING...BUT THE CLOUDS WILL BE THINNER AND THINK THAT CLOUD BURN
OFF
WILL BE QUITE A BIT SOONER THAN WE HAVE SEEN OVER THE PAST COUPLE OF
DAYS. THE INLAND PUSH LOOKS EVEN WEAKER FOR THU AND FRI
MORNINGS...AND IT CURRENTLY LOOKS LIKE MANY VALLEY LOCATIONS WILL
REMAIN STRATUS FREE. THE COMBINATION OF DECREASING CLOUD COVER AND A
GRADUALLY WARMING AIR MASS WILL RESULT IN TEMPERATURES CLIMBING
THROUGH THE REST OF THE WEEK. HIGHS SHOULD REACH WELL INTO THE 70S ON
WED AND INTO THE LOW TO MID 80S THU AND FRI. NW FLOW SHOULD KEEP
TEMPS AT THE COAST CAPPED IN THE 60S.

WILL CONTINUE WITH A SLIGHT CHANCE OF THUNDERSTORMS ALONG THE CASCADE
CREST EACH AFTERNOON AND EVENING THROUGH THE END OF THE WEEK. IT
APPEARS THAT WRAP AROUND FLOW ON THE BACK SIDE OF THE DEPARTING LOW
WILL KEEP SOME WEAK INSTABILITY OVER THE CASCADES THROUGH THU. THE
MODELS CONTINUE TO INDICATE SOME WEAK INSTABILITY FRI AS WE DEVELOP
W/SW FLOW ALOFT. PYLE

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...WEAK RIDGING OVER THE
PACNW FRIDAY NIGHT INTO SATURDAY IS PUSHED OFF TO THE EAST AS A
TROUGH OF LOW PRESSURE MOVES ONSHORE SUNDAY NIGHT. SATURDAY WILL BE
A LOT LIKE FRIDAY WITH CLOUDY SKIES EARLY CLEARING TO PARTLY CLOUDY
SKIES IN THE AFTERNOON. THERE WILL ALSO BE A SLIGHT CHANCE FOR SOME
AFTERNOON/EVENING SHOWERS OR THUNDERSTORMS NEAR THE CASCADE CREST.
WITH THE APPROACH OF THE LOW PRESSURE SYSTEM FROM THE
SOUTHWEST...EXPECT SKIES TO REMAIN MOSTLY CLOUDY TO PARTLY SUNNY ON
SUNDAY KEEPING TEMPERATURES A BIT COOLER...TOO. UNDER WESTERLY FLOW
MODELS STILL SUGGEST A SLIGHT CHANCE FOR SHOWERS OR THUNDERSTORMS IN
THE CASCADES SUNDAY AFTERNOON/EVENING. WHETHER THESE
SHOWERS/THUNDERSTORMS OCCUR WILL DEPEND ON HOW MUCH CLOUD COVER
CLEARS OUT OVER THE CASCADES BY THE AFTERNOON. SUNDAY NIGHT OR EARLY
MONDAY AS THE FRONT MOVES THROUGH ASSOCIATED WITH THE UPPER-LEVEL
LOW PRESSURE SYSTEM...MODELS SUGGEST SHOWERS WILL SPREAD ACROSS THE
AREA THROUGH THE DAY MONDAY. A CHANCE FOR SOME SCATTERED SHOWERS
BEHIND THE FRONT WILL CONTINUE THROUGH TUESDAY. -MCCOY

&&

.AVIATION...MARINE CLOUDS WORKING ITS WAY BACK TO THE COAST THIS
EVENING WITH WIDESPREAD MVFR CIGS EXPECTED. STRATUS AROUND
5000-7000 FEET ACROSS WESTERN WASHINGTON ADVANCING INTO THE
INTERIOR OF NW OREGON. BKN TO OVC CIGS GENERALLY NORTH OF KUAO.
MODELS ALL SHOW ENOUGH LOW LEVEL RELATIVE HUMIDITY TO INDICATE
MORE MARINE CLOUDS OVER MUCH OF OUR AREA TONIGHT AND WEDNESDAY
MORNING...BUT SHOULD BE SHALLOWER THAN TODAY. SO CIGS WILL BE MORE
LIKELY MVFR EXCEPT FOR POSSIBLE IFR ALONG THE COAST AND POSSIBLY
NEAR KEUG. THE LOWER INVERSION SHOULD LEAD TO EARLIER CLEARING ON
WEDNESDAY...POSSIBLY BY NOON.

KPDX AND APPROACHES...VFR CONDITIONS WITH CIGS AROUND 5000 FEET
THROUGH ABOUT 12Z WED. THEN A LOWER LAYER SHOULD FORM PROVIDED
ENOUGH CLEARING FROM THE HIGHER LAYER. ANY MVFR CIGS THAT FORM IS
EXPECTED TO DISSIPATE IN THE 18Z TO 20Z WED TIME FRAME. /MH

&&

.MARINE...NOT MUCH IN THE WAY OF SIGNIFICANT CHANGES. WILL BEGIN
TO SEE A MORE DOMINANT PAIR OF SWELL TRAINS ARRIVE FROM WELL OFF
TO THE WEST AND THE DISTANT SOUTH. ADDITIONALLY STILL HAVE SOME
FRESH SWELL FROM WINDS OFF THE WESTERN BC COAST TO COMBINE AND
PRODUCE SOMEWHAT CHOPPY AND CONFUSED SEAS. ON THE UP SIDE...
DOMINANT SEAS WILL ONLY BRIEFLY COMBINE TO AROUND 7 FT MAXIMUM AT
TIMES OVER THE NEXT COUPLE DAYS AND THUS REMAIN BELOW SMALL CRAFT
CRITERIA. OVERALL WINDS WILL STAY FROM THE WEST NORTHWEST WITH
ONLY BRIEF AND LOCALIZED GUSTS PUSHING OVER 20 KTS OVER THE FAR
SOUTHERN EXTENT OF THE WATERS. /JBONK/PT

&&

.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 262136
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND
236 PM PDT TUE MAY 26 2015

.SYNOPSIS...AN UPPER LEVEL LOW PRES SYSTEM CENTERED OVER EASTERN WA
TODAY WILL MOVE SLOWLY SE INTO IDAHO TONIGHT AND WED. THE LOW WILL
THEN MOVE OFF TO THE E AS A RIDGE OF HIGH PRES BUILDS INTO THE
REGION FROM OFF THE PACIFIC. LOW LEVEL ONSHORE FLOW WILL GRADUALLY
WEAKEN DURING THE COURSE OF THE WEEK...RESULTING IN PROGRESSIVELY
FEWER CLOUDS AND WARMING TEMPS HEADING INTO THE WEEKEND. UPPER LEVEL
LOW PRES WILL LIKELY BRING COOLER TEMPERATURES...MORE CLOUDS...AND
INCREASING SHOWERS LATE IN THE WEEKEND AND EARLY NEXT WEEK.
&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...A SLOW MOVING CLOSED UPPER
LEVEL LOW IS CENTERED NEAR SPOKANE WASHINGTON THIS AFTERNOON.
NUMEROUS SHOWERS AND THUNDERSTORMS HAVE DEVELOPED TODAY UNDER THE
ASSOCIATED COLD POOL ALOFT OVER E WASHINGTON AND FAR NW OREGON. BASED
ON THE LATEST NWS DOPPLER RADAR IMAGERY...THERE ARE NOW
SOME SHOWERS FORMING ALONG THE EASTERN SLOPES OF THE S WASHINGTON
CASCADES. WILL HOLD ON TO A SLIGHT CHANCE FOR THUNDER ALONG THE S
WASH CASCADE CREST IN OUR FCST AREA...ALTHOUGH THINK THAT MOST
OF THE ACTIVITY WILL CONTINUE TO REMAIN ON THE E SLOPES.
ELSEWHERE...MARINE STRATUS CLOUDS HAVE STEADILY DISSIPATED THROUGH
THE DAY. THIS TREND SHOULD CONTINUE THROUGH THE REST OF THE
AFTERNOON...WITH MOST EVERYONE SEEING SOME SUNSHINE BY THE TIME THE
DAY IS OVER.

THE CLOSED LOW WILL CONTINUE TO DRIFT EASTWARD INTO IDAHO TONIGHT AND
WED. THIS WILL ALLOW HEIGHTS TO GRADUALLY RISE AS AN UPPER LEVEL
RIDGE BEGINS TO PUSH TOWARD THE PAC NW. THE ONSHORE FLOW WILL WEAKEN
AS THE LOW LEVEL FLOW TURNS MORE NORTHERLY OVER THE NEXT COUPLE OF
DAYS. THE MARINE LAYER WILL ALSO BECOME INCREASINGLY SHALLOW AS THE
HIGH PRES BUILDS IN. SO EXPECT LESS AND LESS OVERNIGHT MARINE STRATUS
INTRUSION AS WE GET LATER IN THE WEEK. IT STILL LOOKS LIKE CLOUDS
WILL FILL IN OVER A GOOD PORTION OF THE VALLEY TONIGHT AND WED
MORNING...BUT THE CLOUDS WILL BE THINNER AND THINK THAT CLOUD BURN OFF
WILL BE QUITE A BIT SOONER THAN WE HAVE SEEN OVER THE PAST COUPLE OF
DAYS. THE INLAND PUSH LOOKS EVEN WEAKER FOR THU AND FRI
MORNINGS...AND IT CURRENTLY LOOKS LIKE MANY VALLEY LOCATIONS WILL
REMAIN STRATUS FREE. THE COMBINATION OF DECREASING CLOUD COVER AND A
GRADUALLY WARMING AIR MASS WILL RESULT IN TEMPERATURES CLIMBING
THROUGH THE REST OF THE WEEK. HIGHS SHOULD REACH WELL INTO THE 70S ON
WED AND INTO THE LOW TO MID 80S THU AND FRI. NW FLOW SHOULD KEEP
TEMPS AT THE COAST CAPPED IN THE 60S.

WILL CONTINUE WITH A SLIGHT CHANCE OF THUNDERSTORMS ALONG THE CASCADE
CREST EACH AFTERNOON AND EVENING THROUGH THE END OF THE WEEK. IT
APPEARS THAT WRAP AROUND FLOW ON THE BACK SIDE OF THE DEPARTING LOW
WILL KEEP SOME WEAK INSTABILITY OVER THE CASCADES THROUGH THU. THE
MODELS CONTINUE TO INDICATE SOME WEAK INSTABILITY FRI AS WE DEVELOP
W/SW FLOW ALOFT. PYLE

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...WEAK RIDGING OVER THE
PACNW FRIDAY NIGHT INTO SATURDAY IS PUSHED OFF TO THE EAST AS A
TROUGH OF LOW PRESSURE MOVES ONSHORE SUNDAY NIGHT. SATURDAY WILL BE
A LOT LIKE FRIDAY WITH CLOUDY SKIES EARLY CLEARING TO PARTLY CLOUDY
SKIES IN THE AFTERNOON. THERE WILL ALSO BE A SLIGHT CHANCE FOR SOME
AFTERNOON/EVENING SHOWERS OR THUNDERSTORMS NEAR THE CASCADE CREST.
WITH THE APPROACH OF THE LOW PRESSURE SYSTEM FROM THE
SOUTHWEST...EXPECT SKIES TO REMAIN MOSTLY CLOUDY TO PARTLY SUNNY ON
SUNDAY KEEPING TEMPERATURES A BIT COOLER...TOO. UNDER WESTERLY FLOW
MODELS STILL SUGGEST A SLIGHT CHANCE FOR SHOWERS OR THUNDERSTORMS IN
THE CASCADES SUNDAY AFTERNOON/EVENING. WHETHER THESE
SHOWERS/THUNDERSTORMS OCCUR WILL DEPEND ON HOW MUCH CLOUD COVER
CLEARS OUT OVER THE CASCADES BY THE AFTERNOON. SUNDAY NIGHT OR EARLY
MONDAY AS THE FRONT MOVES THROUGH ASSOCIATED WITH THE UPPER-LEVEL
LOW PRESSURE SYSTEM...MODELS SUGGEST SHOWERS WILL SPREAD ACROSS THE
AREA THROUGH THE DAY MONDAY. A CHANCE FOR SOME SCATTERED SHOWERS
BEHIND THE FRONT WILL CONTINUE THROUGH TUESDAY. -MCCOY

&&

.AVIATION...MARINE CLOUDS ARE TRYING TO THIN EARLY THIS AFTERNOON
BUT STILL HANGING TOUGH...ESPECIALLY IN THE EASTERN VALLEYS AND
WEST SLOPES OF THE CASCADES. EXPECT THE CLOUDS TO CONTINUE TO THIN
AND CLEAR TO A LARGE DEGREE THROUGH THE LATTER HALF OF THE AFTERNOON
AND EARLY EVENING. STILL QUITE A BIT OF CLOUDS TO THE NORTH AROUND
PUGET SOUND SO STILL MORE CLOUDS TO ADVECT SOUTH INTO OUR AREA
OVERNIGHT AND WEDNESDAY MORNING. THE MODELS ALL SHOW ENOUGH LOW
LEVEL RELATIVE HUMIDITY TO INDICATE MORE MARINE CLOUDS OVER MUCH
OF OUR AREA TONIGHT AND WEDNESDAY MORNING. THE MODELS ALSO
SUGGEST THAT THE MARINE INVERSION WILL BE LOWERING DURING THE NEXT
24 HOURS...SO CIGS WILL BE MORE LIKELY MVFR EXCEPT FOR POSSIBLE
IFR ALONG THE COAST AND POSSIBLY NEAR KEUG. THE LOWER INVERSION
SHOULD LEAD TO EARLIER CLEARING ON WEDNESDAY...POSSIBLY BY NOON.

KPDX AND APPROACHES...CIGS AROUND 040 SHOULD BECOME SCATTERED
IN THE 2 TO 4 PM TIME FRAME. EXPECT CIGS TO RETURN LATE EVENING
OR AROUND MIDNIGHT...BECOMING MAINLY MVFR CIGS THROUGH MOST OF
WEDNESDAY MORNING. EARLIER CLEARING EXPECTED WEDNESDAY...POSSIBLY
BY NOON. PT

&&

.MARINE...NOT MUCH IN THE WAY OF SIGNIFICANT CHANGES. WILL BEGIN
TO SEE A MORE DOMINANT PAIR OF SWELL TRAINS ARRIVE FROM WELL OFF
TO THE WEST AND THE DISTANT SOUTH. ADDITIONALLY STILL HAVE SOME
FRESH SWELL FROM WINDS OFF THE WESTERN BC COAST TO COMBINE AND
PRODUCE SOMEWHAT CHOPPY AND CONFUSED SEAS. ON THE UP SIDE...
DOMINANT SEAS WILL ONLY BRIEFLY COMBINE TO AROUND 7 FT MAXIMUM AT
TIMES OVER THE NEXT COUPLE DAYS AND THUS REMAIN BELOW SMALL CRAFT
CRITERIA. OVERALL WINDS WILL STAY FROM THE WEST NORTHWEST WITH
ONLY BRIEF AND LOCALIZED GUSTS PUSHING OVER 20 KTS OVER THE FAR
SOUTHERN EXTENT OF THE WATERS. /JBONK/PT

&&

.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.





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