307
FXUS66 KPQR 180428 AAA
AFDPQR
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PORTLAND OR
928 PM PDT WED JUN 17 2026
UPDATED AVIATION DISCUSSION.
SYNOPSIS
WARMER THAN NORMAL AND DRY CONDITIONS ARE EXPECTED
TO CONTINUE THROUGH THE MIDDLE OF NEXT WEEK. CONFIDENCE IS
INCREASING THAT HOT TEMPERATURES PEAKING MONDAY AND TUESDAY WILL
SUPPORT MODERATE TO MAJOR HEATRISK, HOWEVER THERE REMAINS
UNCERTAINTY IN THE TEMPERATURE FORECAST AT THIS LEAD TIME.
DISCUSSION...NOW THROUGH TUESDAY NIGHT
AN UPPER-LEVEL RIDGE
AXIS CURRENTLY CENTERED OVER THE NORTHEASTERN PACIFIC WILL SHIFT
EASTWARD AND INLAND THROUGH THE END OF THE WORKWEEK, BRINGING A
WARMING TREND WITH A TYPICAL SUMMERTIME NORTHERLY WIND PATTERN.
TEMPERATURES WILL PEAK ON THURSDAY AT THE COAST AND ON FRIDAY
INLAND AS TROUGHING ALOFT SUPPORTS A RETURN TO STRONGER ONSHORE
FLOW FRIDAY INTO SATURDAY. TEMPERATURES NEAR 70 DEGREES ON THE
COAST WILL YIELD MINOR HEATRISK ON THURSDAY, WHILE INLAND
TEMPERATURES CLIMB INTO THE 80S TO NEAR 90 DEGREES BOTH THURSDAY
AND FRIDAY, YIELDING WIDESPREAD MINOR HEATRISK AND LOCALLY
MODERATE HEATRISK FROM SALEM NORTH TO KELSO/LONGVIEW AND
PORTLAND EAST THROUGH THE COLUMBIA GORGE. THE CHANCES TO EXCEED
90 DEGREES ON FRIDAY 35-55% FROM PORTLAND/VANCOUVER SOUTH TO
NORTHERN MARION COUNTY, 15-25% IN THE CENTRAL WILLAMETTE VALLEY,
AND 5-15% ELSEWHERE ALONG THE I-5 CORRIDOR. AFOREMENTIONED
TROUGHING AND ONSHORE FLOW WILL YIELD COOLER TEMPERATURES NEAR
60 DEGREES STARTING FRIDAY ON THE COAST, AND UPPER 70S TO LOW
80S WITHIN INLAND VALLEYS ON SATURDAY.
ENSEMBLE GUIDANCE REMAINS IN GOOD AGREEMENT THAT RENEWED RIDGING
WILL DEVELOP FROM SUNDAY INTO EARLY NEXT WEEK, RAISING THE
CHANCES FOR ANOTHER PERIOD OF HOT TEMPERATURES PEAKING MONDAY
AND TUESDAY. UNCERTAINTY IN THE POSITION AND AMPLITUDE OF THE
RIDGE AXIS REMAIN GENERATES ATTENDANT UNCERTAINTY IN THE
TEMPERATURE FORECAST, BUT GIVEN THE MODEL CONSENSUS, THERE ARE
65-95% CHANCES FOR TEMPERATURES TO EXCEED 90 DEGREES THROUGHOUT
INLAND VALLEYS ON MONDAY, AND SLIGHTLY LOWER CHANCES, 55-85%, ON
TUESDAY. THE CHANCES TO EXCEED 95 DEGREES SIMILARLY PEAK AT
GENERALLY 30-60% EACH OF MONDAY AND TUESDAY AFTERNOON, WHILE THE
CHANCES TO REACH 100 DEGREES REACH 5-15% ONLY FROM SALEM NORTH
TO VANCOUVER. THESE DAYTIME TEMPERATURES COMBINED WITH OVERNIGHT
LOWS IN THE UPPER 50S TO LOW 60S SUPPORT WIDESPREAD MODERATE
HEATRISK INLAND BOTH MONDAY AND TUESDAY, WITH THE COVERAGE OF
MAJOR HEATRISK LARGELY DEPENDENT ON THE OCCURRENCE OF OVERNIGHT
TEMPERATURES FALLING TO LOWS ONLY IN THE MID 60S. THE CHANCES OF
MAJOR HEATRISK VERY NEARLY MIRROR THOSE OF NIGHTTIME LOWS OF 65
DEGREES OR WARMER MONDAY NIGHT: 20% NEAR ALBANY/CORVALLIS,
INCREASING NORTHWARD TO 50% IN THE INNER PORTLAND/VANCOUVER
METRO, THEN DECREASING TO 20% NEAR KELSO/LONGVIEW. LONG-RANGE
GUIDANCE FAVORS A COOLING TREND LATER NEXT WEEK, BUT THERE ARE
STILL LOW CHANCES, 10-20%, FOR THE HEAT TO PERSIST INTO A THIRD
DAY NEXT WEDNESDAY. -36
AVIATION
VFR AND DRY OVER THE NEXT 24 HOURS WITH WEAK ONSHORE
FLOW. OVERNIGHT COOLING WITH ONSHORE FLOW WILL LEAD TO MARINE
STRATUS ALONG THE COAST. GREATER THAN A 40% CHANCE OF MVFR CIGS
AROUND KAST AND OTHER COASTAL TERMINALS, DISSIPATING BY 16Z THU.
ELSEWHERE, CHANCES ARE FAR LOWER AROUND 20-30%. SKIES CLEAR ONCE
AGAIN AFTER 17Z THU. ANOTHER BREEZY DAY WITH NORTHERLY TO
NORTHWESTERLY WINDS. HIGHEST WIND SPEEDS WILL BE ALONG THE CENTRAL
OREGON COAST AROUND KONP. GUSTY CONDITIONS THROUGH THE WILLAMETTE
VALLEY BETWEEN 20Z THU AND 02Z FRI, THOUGH CONFIDENCE IN THE
DURATION IS A LITTLE LESS CERTAIN.
KPDX AND APPROACHES...VFR THROUGH THE NEXT 24 HRS WITH A 20%
CHANCE OF BRIEF MVFR STRATUS AROUND SUNRISE THU. NORTHWEST WINDS
INCREASE THIS AFTERNOON TO 8-11 KT WITH GUSTS UP TO 18-20 KT,
EASING AGAIN BY 07Z THU. -27/DH
MARINE
HIGH PRESSURE OFFSHORE WILL MAINTAIN A SUMMERTIME
PATTERN THROUGH THIS WEEK. DIURNALLY DRIVEN NORTHERLIES ARE
EXPECTED TO PEAK EACH AFTERNOON AND EVENING THROUGH AT LEAST
FRIDAY. WINDS ARE EXPECTED TO PEAK EACH AFTERNOON AND EVENING
WITH GUSTS TO 25-30 KTS, DECREASING A BIT IN THE LATE OVERNIGHT
TO MORNING HOURS. WINDS WILL LIKELY EASE OVER THE WEEKEND AS
HIGH PRESSURE WEAKENS AND LOW PRESSURE MOVES INTO NORTHWEST WA,
TURNING WINDS MORE NORTHWESTERLY ON SATURDAY. SEAS AROUND 7 TO 9
FT AT 8-9 SECONDS ARE EXPECTED TO BUILD TO 9 TO 11 FT AT 9-10
SECONDS LATER THURSDAY INTO FRIDAY AS A FRESH NORTHWESTERLY
SWELL PERSISTS ACROSS THE COASTAL WATERS. SEAS ARE EXPECTED TO
SUBSIDE OVER THE WEEKEND. -DH
PQR WATCHES/WARNINGS/ADVISORIES
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FROM 5 AM TO 10 AM PDT THURSDAY FOR
PZZ210.
SMALL CRAFT ADVISORY UNTIL 5 AM PDT FRIDAY 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