783  
FXUS66 KPQR 250455 AAA  
AFDPQR  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE PORTLAND OR  
954 PM PDT SUN MAY 24 2026  
 
UPDATED AVIATION DISCUSSION.  
   
SYNOPSIS  
HIGH PRESSURE CONTINUES TO LINGER OVER THE REGION  
THROUGH THE EVENING, BUT CONFIDENCE REMAINS HIGH THAT A SIGNIFICANT  
PATTERN CHANGE IS ON DECK STARTING TONIGHT. THE CAUSE OF THIS  
COOLER AND WETTER PATTERN IS A GULF OF ALASKA LOW THAT LOOKS TO  
BRING WIDESPREAD RAIN, BREEZY WINDS, AND MUCH COOLER TEMPERATURES  
ACROSS THE AREA. SHOWERS LINGER INTO TUESDAY ALONG WITH A  
SLIGHT CHANCE (10-20%) FOR THUNDERSTORMS. CONDITIONS TREND  
WARMER AND DRIER THROUGH THE MIDDLE OF THE WEEK AND INTO NEXT  
WEEKEND.  
 
 
   
DISCUSSION...NOW THROUGH SATURDAY  
CLEAR SKIES THIS EVENING  
WILL SOON BE REPLACED BY WIDESPREAD CLOUD COVER STARTING  
TONIGHT. GOES FULL DISK, SATELLITE OBSERVATIONS SHOWS A BROAD  
UPPER LEVEL LOW COVERING A VAST AREA OF THE NORTHEASTERN  
PACIFIC OCEAN. PUTTING THE SATELLITE ON A LOOP, THIS LOW IS  
MOVING EASTWARD WHICH WILL RESULT IN A COLD FRONT BEING PUSHED  
ACROSS THE PAC NW. THIS FRONT WILL BRING WIDESPREAD RAIN AND  
THICK CLOUD COVER ACROSS OUR CWA. RAIN SHOULD BEGIN ALONG THE  
COAST AROUND 5AM-7AM MONDAY MORNING, WITH RAIN STARTING TO  
IMPACT INLAND LOCATIONS AROUND 12PM-2PM MONDAY. RECENT GUIDANCE  
SUPPORTS 24 HOUR RAINFALL TOTALS (ROUGHLY 5 AM MONDAY TO 5 AM  
TUESDAY) IN THE 0.15"-0.80", WITH THE GREATEST TOTALS ALONG THE  
COAST AND COAST RANGE. PROBABILITIES FOR AT LEAST 0.25 INCH ARE  
GENERALLY 35-75% FOR THE WILLAMETTE VALLEY AND 60-95% FOR THE  
COAST, COAST RANGE, AND CASCADES. PROBABILITIES FOR 0.50 INCH  
OR MORE ARE GENERALLY 5-30% FOR THE WILLAMETTE VALLEY AND 60-95%  
FOR THE COAST AND COAST RANGE, AND GENERALLY 15-45% FOR THE  
CASCADES. A CORRIDOR FROM FLORENCE OR NORTH TOWARD SEASIDE OR  
CONTINUES TO SHOW THE BEST CHANCES, AROUND 20-40% FOR 1.0" OR  
MORE.  
 
WINDS WILL ALSO PICK UP EARLY MONDAY AS THE FRONT MOVES  
THROUGH. CURRENTLY PROBABILITIES STRONGLY FAVOR GUSTS EXCEEDING  
25 MPH ACROSS MUCH OF THE AREA (AROUND 80-99%). GUSTS OVER 30  
MPH ARE MORE LIKELY ALONG THE COAST (60-90%) THAN INLAND  
(25-60%). HIGHER-END GUSTS AROUND 35 MPH OR GREATER REMAIN A  
LOWER-PROBABILITY OUTCOME FOR INLAND LOCATIONS (5-15%) BUT ARE  
MORE FAVORED ALONG THE COAST (30-50%). EVEN WITHOUT ADVISORY-  
LEVEL WINDS EXPECTED INLAND, THESE SPEEDS CAN STILL IMPACT  
TENTS, CANOPIES, AND OTHER UNSECURED ITEMS.  
 
BY TUESDAY, THE LOW SHIFTS SOUTHEASTWARD WITH SHOWERS LINGERING  
AND A MORE SOUTHERLY FLOW DEVELOPING. THAT SETUP IS MORE  
SUPPORTIVE OF THUNDERSTORMS, WHICH IS RESULTING IN A 10-20%  
CHANCE FOR THE WILLAMETTE VALLEY AND CASCADES BY LATE TUESDAY  
MORNING THROUGH LATE TUESDAY EVENING.  
 
FROM MIDWEEK THROUGH NEXT WEEKEND, GUIDANCE TRENDS TOWARD A  
WARMING AND DRYING PATTERN AS WEAKER HIGH PRESSURE/ZONAL FLOW  
RETURNING. FOR REFERENCE, DAYTIME HIGHS WILL LIKELY (70-85%)  
REMAIN SLIGHTLY COOLER THAN THIS WEEKEND. WHILE CONFIDENCE  
REMAINS LOW, ENSEMBLE GUIDANCE SUGGESTS THAT THE WEAK HIGH  
PRESSURE RIDGE WILL WEAKEN FRIDAY AS A BROAD TROUGH OVER THE  
NORTHEAST PACIFIC NEARS THE PACIFIC NORTHWEST. /42~12  
 
ON A SLIGHTLY PERSONAL NOTE, WITH MONDAY BEING MEMORIAL DAY, IT  
IS TIME TO REMEMBER THOSE WHO SERVED THAT ARE NO LONGER WITH  
US. I WANT TO REMIND EVERYONE THAT IF YOU ARE A FELLOW VETERAN  
OR KNOW A VETERAN THAT NEEDS HELP, YOU CAN ALWAYS CALL THE VA  
CRISIS LINE BY DIALING 988 AND PRESSING 1 OR TEXT 838255  
24/7/365. WE MUST TAKE CARE OF AND LOOK OUT THOSE WHO STOOD  
BESIDES US, WHO CAME BEFORE US AND WHO WILL FOLLOW IN OUR  
FOOTSTEPS. SEMPER FI. /42  
 
 
   
AVIATION  
A FRONTAL SYSTEM REMAINS JUST OFFSHORE THIS EVENING  
WHICH WILL BE THE WEATHER MAKER OVER THE NEXT 24 HOURS. MOST  
LOCATIONS REMAIN VFR EXCEPT A FEW ISOLATED AREAS ALONG THE CENTRAL  
OREGON COAST. A LAYER OF MARINE STRATUS IS WORKING IT'S WAY  
NORTHWARD AND SHOULD IMPACT KONP IN THE NEXT FEW HOURS. 50% CHANCE  
OF IFR CONDITIONS AND GREATER THAN AN 80% CHANCE OF MVFR ALONG  
COASTAL TERMINALS. THE NORTH COAST THOUGH WILL LIKELY STAY OUT OF  
A BULK OF THAT STRATUS DUE TO MIXING FROM THE FRONTAL PASSAGE  
AFTER 12Z MON. WINDS WILL CONTINUE TO SHIFT THROUGH THE PERIOD  
BECOMING SOUTHWESTERLY IN THE AFTERNOON WITH THE FRONT. AS THEY  
DO, EXPECT GUSTY WINDS WITH MANY AIRPORTS SEEING GUSTS IN EXCESS  
OF 20 KT. SOME AREAS WITHIN THE COLUMBIA RIVER GORGE WILL BE EVEN  
WINDIER WITH SOME MODELS SUGGESTING AS HIGH AS 30 KT AT 3000 FT.  
 
RAIN EXPECTED OVER THE REGION WITH A 15-30% CHANCE OF  
THUNDERSTORMS AFTER 18Z MON. TRENDING ON THE LOWER END OF THAT  
RANGE, BUT CANNOT RULE OUT AN ISOLATED THUNDERSTORM OR TWO -  
THOUGH CONFIDENCE IS MUCH LOWER THAN IN PREVIOUS FORECASTS. HAVE  
INCLUDED PROB30 IN THE TAF FOR KAST, KONP, KHIO, KPDX, AND KTTD.  
THIS IS NOT LOOKING LIKE A WIDESPREAD THUNDERSTORM SYSTEM BUT  
RATHER A FEW ONE-HIT-WONDERS.  
 
KPDX AND APPROACHES...PREDOMINATELY VFR CONDITIONS THROUGH THE  
TAF PERIOD WITH INCREASING SCT/BKN HIGH CLOUDS AHEAD OF THE NEXT  
SYSTEM. AFTER 13-15Z MON, SOUTHERLY WINDS INCREASE WITH GUSTS UP  
TO 20 KT AS THE FRONT APPROACHES. CIGS ALSO GRADUALLY FALL TO LOW-  
END VFR AFTER 19Z MON WITH AROUND A 15% CHANCE OF MVFR CIGS.  
RAIN IN THE AREA WITH GUSTY WINDS MAY TEMPORARILY REDUCE VIS AT  
TIMES. PROB30 INCLUDED LATE IN THE FORECAST FOR THUNDERSTORMS BUT  
CONFIDENCE IS LOW. AT THIS POINT, THERE IS A HIGH LEVEL OF  
UNCERTAINTY IN REGARDS TO WHETHER OR NOT WE WILL SEE ANY KIND OF  
THUNDERSTORM ACTIVITY SO THOSE PROBS COULD BE REMOVED IN LATER  
FORECASTS. -27  
 
 
   
MARINE  
NORTHERLY WINDS WILL GRADUALLY TURN MORE SOUTHERLY THIS  
AFTERNOON AND EVENING AHEAD OF THE NEXT FRONTAL SYSTEM. TONIGHT,  
SOUTHERLY WINDS INCREASE WITH WIDESPREAD GUSTS UP TO 30 KT ACROSS  
ALL WATERS AS THE NEXT FRONT MOVES THROUGH. PEAK WINDS ARE  
EXPECTED BETWEEN 5-11 AM MONDAY WITH A 50-70% CHANCE FOR ISOLATED  
GALE FORCE GUSTS UP TO 35 KT FOR THE INNER WATERS (FROM SHORE TO  
10 NM OUT) NORTH OF CAPE FOULWEATHER. AFTER 11 AM MONDAY, WINDS  
TURN MORE WEST-SOUTHWESTERLY BEHIND THE FRONT WITH GUSTS UP TO 25  
KT. SMALL CRAFT ADVISORIES ARE IN EFFECT FROM 11 PM SUNDAY  
THROUGH 5 PM MONDAY FOR ALL WATERS INCLUDING THE COLUMBIA RIVER  
BAR. SEAS AROUND 6 TO 8 FT THROUGH EARLY MONDAY MORNING.  
 
FOLLOWING THE FRONTAL PASSAGE, A WESTERLY SWELL WILL MOVE IN A  
BUILD SEAS ABOVE 13 FT (>90% CHANCE). THERE IS ALSO A 5-10% CHANCE  
FOR SEAS EXCEEDING 20 FT MONDAY NIGHT INTO TUESDAY MORNING, WITH  
THE HIGHEST CHANCES FOR THE OUTER WATERS BEYOND 30 NM OFFSHORE.  
GIVEN THE POTENTIAL FOR SEAS BETWEEN 15-20 FT, THERE REMAINS A  
HAZARDOUS SEAS WATCH FOR ALL WATERS INCLUDING THE COLUMBIA RIVER  
BAR BETWEEN 5 PM MONDAY TO 11 AM TUESDAY. SEAS SUBSIDE TO 10-12  
FT BY TUESDAY EVENING AND GRADUALLY SUBSIDE INTO WEDNESDAY. WILL  
ALSO NOTE THAT THERE IS A 10-20% CHANCE FOR THUNDERSTORMS ACROSS  
THE WATERS MONDAY NIGHT. ANY PASSING THUNDERSTORMS MAY PRODUCE  
LIGHTNING, BRIEF HEAVY DOWNPOURS THAT REDUCE VISIBILITY, ERRATIC  
WINDS, AND/OR SMALL HAIL. -10  
 
 
   
PQR WATCHES/WARNINGS/ADVISORIES  
 
OR...NONE.  
WA...NONE.  
PZ...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING TO 5 PM PDT MONDAY  
FOR PZZ210-251>253-271>273.  
 
HAZARDOUS SEAS WATCH FROM MONDAY AFTERNOON THROUGH TUESDAY  
MORNING FOR PZZ210-251>253-271>273.  
 
 
 
 
 
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