514
FXUS66 KPQR 031154
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
354 AM PST TUE FEB 3 2026
SYNOPSIS
HIGH PRESSURE CONTINUES TO BUILD OVER THE PACIFIC NORTHWEST
TODAY, ESTABLISHING A DRY AND MILD PATTERN THAT IS EXPECTED TO
PERSIST THROUGH AT LEAST FRIDAY. CLEAR SKIES, LIGHT WINDS, AND
PERSISTENT LOW-LEVEL INVERSIONS WILL SUPPORT AREAS OF FOG AND
FROST ACROSS INTERIOR LOWLAND VALLEYS THROUGH MUCH OF THE WEEK.
IN ADDITION, STAGNANT AIR CONDITIONS MAY DEVELOP IN SOME
INTERIOR VALLEYS. BREEZY EASTERLY WINDS THROUGH THE COLUMBIA
RIVER GORGE WILL HELP LIMIT AIR STAGNATION IMPACTS ACROSS THE
PORTLAND AND VANCOUVER METRO AREA AND PORTIONS OF THE WEST-
CENTRAL WILLAMETTE VALLEY.
DISCUSSION...NOW THROUGH SUNDAY
UPPER-LEVEL RIDGING BECOMES
FIRMLY ESTABLISHED OVER THE REGION TODAY, MARKING THE START OF
AN EXTENDED PERIOD OF DRY WEATHER AND ABOVE-NORMAL TEMPERATURES.
MID TO HIGH-LEVEL CLOUD COVER MAY LINGER THROUGH PORTIONS OF THE
DAY AS A PACIFIC SYSTEM TRACKS WELL NORTH INTO BRITISH COLUMBIA
ALONG THE NORTHERN PERIPHERY OF THE RIDGE. HOWEVER, CLOUDS ARE
EXPECTED TO GRADUALLY THIN AND CLEAR, WITH SUNNIER CONDITIONS
BECOMING MORE WIDESPREAD WEDNESDAY AND THURSDAY. AFTERNOON HIGH
TEMPERATURES THROUGH THE END OF THE WORK WEEK ARE FORECAST TO
REACH THE UPPER 50S TO LOWER 60S, ROUGHLY 10 DEGREES ABOVE
CLIMATOLOGICAL AVERAGE FOR EARLY JANUARY. WEDNESDAY LOOKING TO
BE THE WARMEST DAY OF THE WORK WEEK BY A DEGREE OR TWO.
DESPITE THE MILD DAYTIME TEMPERATURES, CLEAR NIGHTS AND LIGHT
WINDS WILL PROMOTE STRONG NOCTURNAL INVERSIONS ACROSS INTERIOR
VALLEYS. THESE INVERSIONS WILL FAVOR THE DEVELOPMENT OF FOG AND
LOW STRATUS DURING THE OVERNIGHT AND MORNING HOURS, PARTICULARLY
WITHIN THE WILLAMETTE VALLEY AND OTHER SHELTERED LOWLAND
LOCATIONS. THERE REMAINS SOME UNCERTAINTY REGARDING THE LOW-
LEVEL MOISTURE, AS MODEL SOUNDINGS INDICATE EASTERLY TO EAST-
SOUTHEASTERLY FLOW AROUND 1000 TO 2000 FEET ABOVE GROUND LEVEL
MAY INHIBIT STRATUS FORMATION IN SOME AREAS WHILE SURFACE WINDS
REMAIN CALM. THIS SCENARIO WOULD RESULT IN A FAVORED FOG PATTERN
RATHER THAN STRATUS, ESPECIALLY IN LOCATIONS REMOVED FROM THE
INFLUENCE OF THE COLUMBIA RIVER GORGE OUTFLOW. PATCHY FROST
WILL ALSO BE POSSIBLE DURING THE OVERNIGHT AND EARLY MORNING
HOURS WHERE SKIES REMAIN CLEAR AND WINDS DECOUPLE.
WINDS DURING THE RIDGING PERIOD WILL GENERALLY BE LIGHT ACROSS
MOST OF THE FORECAST AREA, THOUGH NOTABLE EXCEPTIONS ARE
EXPECTED IN AND NEAR THE COLUMBIA RIVER GORGE. STRENGTHENING
EAST-WEST PRESSURE GRADIENTS WILL LEAD TO BREEZY EASTERLY GAP
WINDS, PARTICULARLY ON WEDNESDAY AND THURSDAY. DETERMINISTIC AND
ENSEMBLE GUIDANCE SUGGESTS PRESSURE GRADIENTS BETWEEN TROUTDALE
AND THE DALLES WILL RANGE FROM APPROXIMATELY -5 TO -6 MB ON
WEDNESDAY AND INCREASING OVERNIGHT TO AROUND -7 TO -8 MB BY
THURSDAY MORNING. FEW MEMBERS INDICATE GRADIENTS AS STRONG AS
-9 MB DURING THURSDAY MORNING. PROBABILITIES FOR WIND GUSTS
EXCEEDING 35 MPH ARE AROUND 15 TO 25 PERCENT IN THE FAR EASTERN
PORTLAND AND VANCOUVER METRO AREA ON WEDNESDAY AND 25 TO 35
PERCENT ON THURSDAY. ADDITIONALLY, THERE IS A 70 TO 90 PERCENT
CHANCE FOR GUSTS TO EXCEED 35 MPH WITHIN THE WESTERN GORGE AND
ADJACENT TERRAIN. EXPOSED RIDGETOPS SUCH AS CROWN POINT AND
THREE CORNER ROCK HAVE A 30 TO 50% CHANCE OF EXPERIENCING GUSTS
EXCEEDING 50 MPH.
AWAY FROM THE GORGE, PERSISTENT RIDGING, LIGHT WINDS, AND LOW
MIXING HEIGHTS WILL CONTRIBUTE TO STAGNANT AIR CONDITIONS. AN
AIR STAGNATION ADVISORY REMAINS IN EFFECT FROM EARLY TUESDAY
MORNING THROUGH FRIDAY AFTERNOON FOR THE SOUTHERN WILLAMETTE
VALLEY, EAST-CENTRAL WILLAMETTE VALLEY, NORTH AND CENTRAL OREGON
CASCADE FOOTHILLS, NORTH CLARK COUNTY LOWLANDS, AND THE LOWER
COLUMBIA AND COWLITZ RIVER VALLEYS. THE PORTLAND AND VANCOUVER
METRO AREA AND THE WEST-CENTRAL WILLAMETTE VALLEY WERE EXCLUDED
FROM THE ADVISORY DUE TO BETTER LOW-LEVEL MIXING ASSOCIATED WITH
EASTERLY GORGE WINDS, WHICH GRADUALLY VEER MORE NORTHERLY
FARTHER SOUTH INTO THE WEST-CENTRAL VALLEY. IN ADDITION TO AIR
QUALITY CONCERN, THE STAGNANT PATTERN WILL CONTINUE TO SUPPORT
FOG AND FROST POTENTIAL ACROSS INTERIOR VALLEYS THROUGHOUT THE
WEEK, WITH FRONT POTENTIAL MOST NOTABLE ON THURSDAY AND FRIDAY.
ATTENTION THEN TURNS TO THE WEEKEND, WHEN CONFIDENCE DECREASES
REGARDING THE TIMING OF THE NEXT PRECIPITATION EVENT. ENSEMBLE
GUIDANCE INDICATES A RETURN TO WETTER CONDITIONS IS LIKELY,
THOUGH TIMING VARIES. APPROXIMATELY 75 PERCENT OF ENSEMBLE
MEMBERS BRING PRECIPITATION BACK INTO THE REGION BY SATURDAY
AFTERNOON, WHILE OTHERS DELAY THE ONSET UNTIL SUNDAY MORNING.
MOST ENSEMBLE GUIDANCE ALSO SUGGEST A TRANSITION TOWARD COOLER
TEMPERATURES THROUGH THE WEEKEND AND INTO NEXT WEEK. WHILE
DETAILS REMAIN UNCERTAIN, THE OVERALL PATTERN SUGGESTS A COOLER
AND WETTER REGIME DEVELOPING LATE THIS WEEKEND INTO EARLY NEXT
WEEK. ~12
AVIATION
SATELLITE SHOWS A FEW HIGH CLOUDS OVER THE REGION BUT
CONDITIONS REMAIN VFR. HIGH PRESSURE IS BEGINNING TO DEVELOP OVER
THE REGION WHICH IS LEADING TO STABLE CONDITIONS. THE CLEAR SKIES
AND HIGH THIN CLOUDS FROM EARLIER IN THE EVENING HAVE ALLOWED FOR
RADIATIONAL COOLING AND THUS FOG HAS BEGUN TO FORM. FOG IS
DENSEST AROUND KHIO, KKLS, AND WITHIN PORTIONS OF THE WILLAMETTE
VALLEY. HOWEVER, AREAS OF ELEVATED WINDS HAVE REMAINED FOG FREE.
SCATTERED LIFR STRATUS IS PRESENT THOUGH IN AREAS WITHOUT FOG IN
THE WILLAMETTE VALLEY. EASTERLY OFFSHORE WINDS ALONG THE COAST
WILL KEEP THOSE AREAS FOG- FREE. FOG WILL LIKELY BE SPOTTY
DEVELOPING THEN DISSIPATING THROUGH THE NIGHT.
AS THE SUN RISES, SUN WILL BURN OFF MOST AREAS OF FOG LEADING TO
CLEAR AND DRY CONDITIONS WITH VFR VIS/CIGS. WINDS WILL REMAIN
EASTERLY THROUGH THE COLUMBIA RIVER GORGE WITH GUSTS AROUND KTTD
REACHING AROUND 20 KT. WITHIN THE WILLAMETTE VALLEY, WINDS ABOVE
1000 FT AGL WILL BE SOUTHERLY WHILE AT THE SURFACE WINDS WILL BE
VARIABLE. 30-40% CHANCE OF IFR CONDITIONS REFORMING FROM KUAO
SOUTH AFTER 09Z WED.
KPDX AND APPROACHES...QUITE VARIABLE CONDITIONS WITH A FEW/SCT
LAYER AT 100 FT AGL. FOG IS BEGINNING TO FORM, BUT WILL BE PATCHY
AND WILL SURGE IN AND OUT. DUE TO VERY HIGH CLOUDS, THERE MAY BE
ENOUGH INSULATION FOR DENSE FOG TO FORM. THERE IS LESS THAN A 10%
CHANCE OF DENSE FOG FORMATION (1/2 SM OR LESS) SO HAVE TRENDED
TOWARDS MVFR VIS TO ACCOUNT FOR THE PATCHY FOG. WINDS WILL BECOME
EASTERLY AROUND 18Z TUE CAUSING THE LOWER ATMOSPHERE TO DRY AND
CONDITIONS TO IMPROVE. AFTER 06Z WED, IF CONDITIONS REMAIN
EASTERLY THEN THERE IS A LOW PROBABILITY OF FOG REFORMATION.
-27
MARINE
VARIABLE WINDS WITH GUSTS UP TO 15 KT WILL BE THE TREND
OVER THE NEXT 24-HOURS. WIND WAVES WILL BE MINIMAL THROUGH AT
LEAST THURSDAY. THE SMALL CRAFT ADVISORY IS BEING PRIMARILY DRIVEN
BY THE OVERALL COMBINED SEAS. CURRENTLY, BUOYS SHOW OBSERVATIONS
HOVERING RIGHT AROUND THE 10 FT AT 11 SECONDS MARK WITH A FEW
OBSERVATIONS SHOWING SLIGHTLY BELOW THRESHOLD CONDITIONS. THIS
WILL BE THE TREND FOR AT LEAST THE NEXT SEVERAL HOURS SO HAVE
EXTENDED THE SCA THROUGH 7 AM TODAY. HOWEVER, IF CONDITIONS
PERSIST THAT ADVISORY MAY HAVE TO BE EXTENDED. MINIMAL THREAT FOR
ANY MARINE RELATED HAZARDS, BUT SMALL CRAFT ADVISORY LEVEL SEAS
RETURN AS EARLY AS 2200 TONIGHT. SEAS AGAIN HOVER RIGHT ALONG THE
THRESHOLD SO HAVE NOT ISSUED ANOTHER HAZARD AT THIS TIME. HOWEVER,
AS NEWER MODEL DATA COMES IN THAT WILL BE REEVALUATED. WILL SEE
MORE PERSISTENT CONDITIONS OF SEAS AROUND 9-11 FT AT 12 SECONDS
THROUGH AT LEAST THURSDAY. -27
BEACH HAZARDS
WHILE A BEACH HAZARD STATEMENT IS NO LONGER IN
EFFECT FOR SNEAKER WAVES, THERE REMAINS A MARGINAL THREAT FOR
SNEAKER WAVES TODAY. PERIODS WILL HOVER AROUND 11-12 SECONDS WHICH
IS PROMPTING THE END OF THE STATEMENT. HOWEVER THE RISK REMAINS.
CONTINUE TO BE VIGILANT FOR THE INCREASED POTENTIAL, ESPECIALLY
FOR THOSE WHO MAY BE CLAMMING ON BEACHES TODAY. MARGINAL RISK
PROMPTING CONDITIONS PERSIST THROUGH MUCH OF THE WEEK.-27
PQR WATCHES/WARNINGS/ADVISORIES
OR...AIR STAGNATION ADVISORY UNTIL 4 PM PST FRIDAY FOR ORZ108-115>118-
123>125.
WA...AIR STAGNATION ADVISORY UNTIL 4 PM PST FRIDAY FOR WAZ204-205.
PZ...SMALL CRAFT ADVISORY UNTIL 7 AM PST THIS MORNING FOR PZZ210-
251>253-271>273.
WWW.WEATHER.GOV/PORTLAND
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X.COM/NWSPORTLAND
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