778
FXUS66 KPQR 200432 AAA
AFDPQR
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PORTLAND OR
ISSUED BY NATIONAL WEATHER SERVICE SEATTLE WA
930 PM PDT MON MAY 19 2025
..UPDATED AVIATION DISCUSSION
SYNOPSIS
SCATTERED SHOWERS CONTINUE THROUGH TUESDAY WITH
TEMPERATURES REMAINING BELOW NORMAL. TEMPERATURES WARM BACK TO
NEAR NORMAL WEDNESDAY INTO FRIDAY WITH AN UNSETTLED PATTERN
CONTINUING. THEN, THERE IS THE POTENTIAL FOR WARMER THAN NORMAL
TEMPERATURES THIS WEEKEND.
SHORT TERM...MONDAY AFTERNOON THROUGH WEDNESDAY
OBSERVATIONS
EARLY MONDAY AFTERNOON INDICATE THE SURFACE FRONT THAT PASSED
THROUGH THE REGION THIS MORNING IS NOW SITUATED EAST OF THE
CASCADES. SHOWERS HAVE BECOME MUST MORE ISOLATED IN NATURE AND
ARE MAINLY LIMITED TO THE MOUNTAINS AND SW WASHINGTON. A SLIGHT
CHANCE (10-15%) OF STRONGER SHOWERS OR THUNDERSTORMS REMAINS
OVER THE PACIFIC COUNTY AND CLATSOP COUNTY COASTS, THOUGH LITTLE
IMPACTS ARE EXPECTED EXCEPT FOR BRIEF PERIODS OF HEAVY RAIN AND
GUSTY AND ERRATIC WINDS. SATELLITE DATA SHOWS MOSTLY CLEAR
SKIES OVER THE WILLAMETTE VALLEY AND CLARK COUNTY LOWLANDS,
WHICH HAS ALLOWED TEMPERATURES TO ALREADY RISE INTO THE LOW TO
MID 60S AS OF 2PM PDT. WINDS HAVE INCREASED BEHIND THE FRONTAL
PASSAGE WITH GUSTS UP TO 20-25 MPH AT TIMES, DECREASING IN THE
OVERNIGHT HOURS TONIGHT. SCATTERED SHOWERS WILL CONTINUE ACROSS
ALL OF NW OREGON AND SW WASHINGTON THROUGH TOMORROW AFTERNOON AS
WEAK TROUGHING KEEPS UNSETTLED CONDITIONS OVER THE REGION.
TEMPERATURES WILL BE SIMILAR IF NOT A FEW DEGREES COOLER,
TOPPING OUT IN THE LOW 60S.
A WEAK TRANSIENT RIDGE WILL MOVE OVER THE REGION ON WEDNESDAY,
ALLOWING DRY CONDITIONS TO BRIEFLY RETURN. DAYTIME TEMPERATURES
ARE FORECAST TO RISE BACK TO NEAR NORMAL FOR MID- MAY, PEAKING
IN THE UPPER 60S TO RIGHT AROUND 70 DEGREES ACROSS THE INTERIOR
LOWLANDS AND UPPER 50S TO LOW 60S. NBM INDICATES A 40-60% CHANCE
OF TEMPERATURES EXCEEDING 70 DEGREES IN THE PORTLAND/VANCOUVER
METRO AREA, THOUGH ONLY A 30-40% CHANCE FOR THE REST OF THE
INTERIOR LOWLANDS. -HEC
LONG TERM...WEDNESDAY NIGHT TO SUNDAY
ENSEMBLE GUIDANCE IS IN
AGREEMENT THAT A WEAK UPPER TROUGH WILL PUSH INTO THE PACNW FROM THE
WEST LATE WEDNESDAY INTO THURSDAY MORNING. THIS WILL BRING ANOTHER
ROUND OF LIGHT SHOWERS TO THE REGION. HOWEVER, WITH LIMITED MOISTURE
AND FORCING ASSOCIATED WITH THIS SYSTEM, LOCATIONS WEST OF THE
CASCADES MAY SEE LITTLE TO NO RAINFALL. EVEN OVER THE CASCADES,
SHOWERS ARE EXPECTED TO BE SCATTERED WITH ONLY 0.01-0.2 INCHES OF
RAIN POSSIBLE, MAINLY IN THE OVERNIGHT WEDNESDAY AND EARLY MORNING
HOURS ON THURSDAY. DAYTIME TEMPERATURES THURSDAY ARE EXPECTED TO
BACK TO NEAR NORMAL AGAIN, WITH NBM INDICATING A 45-65% CHANCE OF
TEMPERATURES REACHING OR EXCEEDING 70 DEGREES.
FOR FRIDAY INTO SATURDAY, ENSEMBLE SOLUTIONS ARE COMING INTO
BETTER AGREEMENT OF ANOTHER WEAK TROUGH PUSHING WEST INTO THE
PACNW ON FRIDAY, THOUGH UNCERTAINTY REMAINS ON TIMING. ABOUT
HALF OF THE WPC 500MB CLUSTERS SUGGEST THE TROUGH WILL MOVE
THROUGH THE AREA QUICKLY WITH RIDGING RETURNING BY SATURDAY. THE
OTHER HALF INDICATE TROUGHING WILL CONTINUE INTO SATURDAY. THIS
IS LEADING TO A FORECAST TEMPERATURE SPREAD FOR INLAND AREAS OF
ANYWHERE FROM THE UPPER 60S TO MID 70S ON SATURDAY. AT THIS
POINT, NBM INDICATES A 55-65% CHANCE OF TEMPERATURES EXCEEDING
70 DEGREES. THIS PROBABILITY INCREASES TO 70-85% FOR SUNDAY WITH
A 30-55% CHANCE OF TEMPERATURES EXCEEDING 80 DEGREES AS AROUND
75% OF CLUSTERS SHOW RIDGING FORMING SOMEWHERE OVER THE WESTERN
US AND IMPACTING THE PACNW, THOUGH SIGNIFICANT DIFFERENCES
REMAIN IN LOCATION AND INTENSITY OF THE RIDGING. -HEC
AVIATION
RADAR IMAGERY AND SURFACE OBSERVATIONS AS OF MONDAY
EVENING DEPICT LIGHT SHOWER ACTIVITY ACROSS SOUTHWEST WASHINGTON AND
THE NORTH OREGON COAST AS A WEAK UPPER LEVEL SYSTEM MOVES OVERHEAD.
SHOWERS ARE EXPECTED TO REMAIN LIGHT TONIGHT INTO TUESDAY MORNING,
WITH PREDOMINATELY LOW-END VFR CIGS ACROSS ALL TERMINALS. THE COAST
COULD HAVE INTERMITTENT MVFR CIGS, WITH GUIDANCE SUGGESTING A 30-50%
CHANCE FOR CIGS BELOW 3 KFT ALONG THE COAST THROUGH TUESDAY
AFTERNOON. MEANWHILE, PROBABILITIES REMAIN AROUND 15-30% FOR MVFR
CIGS ACROSS THE WILLAMETTE VALLEY THROUGH 18Z TUE. EXPECT MORE CLOUD
BREAKS FOR INLAND TERMINALS TUESDAY AFTERNOON/EVENING AS THE WEAK
SYSTEM EXITS THE AREA. WINDS GENERALLY SOUTHWESTERLY ACROSS THE
REGION AROUND 10 KT OR LESS.
PDX AND APPROACHES...PREDOMINATELY VFR THROUGH THE TAF PERIOD WITH A
20-30% CHANCE FOR INTERMITTENT MVFR CIGS. ANY LINGERING SHOWERS ARE
EXPECTED TO BE LIGHT AND NOT CAUSE VIS IMPACTS. WEST SOUTHWESTERLY
WINDS UNDER 10 KT EXPECTED. -ALVIZ
MARINE
CURRENTLY AS OF 2 PM, RATHER GUSTY WESTERLY WINDS IN
THE WAKE OF A FRONT, MOST COMMONLY IN THE 15-20 KT RANGE. SEAS WILL
ALSO REMAIN LOCALLY STEEP AND CHAOTIC IN THE 6-8 FT RANGE DUE TO
LINGERING SHORT PERIOD WAVE ENERGY AND A PERSISTENT WESTERLY SWELL.
AN ACTIVE SMALL CRAFT ADVISORY HAS COME TO AN END AS CONDITIONS
DIMINISH THIS AFTERNOON. EXPECT SOMEWHAT OF A LULL IN CONDITIONS
THIS EVENING AS WINDS AND SHORT PERIOD SEAS GRADUALLY DIMINISH, BUT
THE BREAK WILL BE SHORT LIVED AS A FRESH ARRIVING MID PERIOD
WESTERLY SWELL BUILDS TO AROUND 10-12 FT LATE TONIGHT THROUGH
TUESDAY, WARRANTING ANOTHER ROUND OF SMALL CRAFT ADVISORIES. AS A
RESULT, A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR ALL WATERS FROM
11 PM MONDAY TO 8 PM TUESDAY. ADDITIONALLY, A SMALL CRAFT ADVISORY
HAS BEEN ISSUED FOR THE COLUMBIA BAR FROM 5 AM TO 2 PM TUESDAY.
SEAS SUBSIDE BACK TO 5-7 FEET ON WEDNESDAY, USHERING A PERIOD OF
RELATIVELY CALMER CONDITIONS THROUGH THE END OF THE WEEK. WEAK HIGH
PRESSURE LOOKS TO BRING A ROUND OF LIGHT TO MODERATE NORTHERLY
BREEZES TO THE WATERS WEDNESDAY AND THURSDAY, WITH BENIGN ONSHORE
FLOW THEN TAKING OVER FRIDAY INTO NEXT WEEKEND. ~HALL/CB
PQR WATCHES/WARNINGS/ADVISORIES
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FROM 5 AM TO 2 PM PDT TUESDAY FOR PZZ210.
SMALL CRAFT ADVISORY UNTIL 8 PM PDT TUESDAY FOR PZZ251>253-
271>273.
WWW.WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA:
WWW.FACEBOOK.COM/NWSPORTLAND
X.COM/NWSPORTLAND
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page