127
FXUS66 KPQR 092356
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
0456 PM PDT THU JUL 9 2026
SYNOPSIS
PERSISTENT ONSHORE FLOW WILL CONTINUE TO YIELD DRY
AND SEASONABLE WEATHER THROUGH THIS WEEKEND. TEMPERATURES TREND
WARMER EARLY NEXT WEEK AS HIGH PRESSURE BUILDS OVER THE PLAINS.
BEYOND MIDWEEK, FORECAST UNCERTAINTY INCREASES BUT DRY AND
HOTTER WEATHER IS FAVORED.
DISCUSSION...NOW THROUGH WEDNESDAY
PLEASANT, SEASONABLE, AND
BENIGN WEATHER IS EXPECTED TO CONTINUE THROUGH THIS WEEKEND AS
ZONAL FLOW ALOFT TURNS SOUTHWESTERLY AHEAD OF AN UPPER-LEVEL
TROUGH MOVING ONSHORE INTO BRITISH COLUMBIA ON SATURDAY.
TEMPERATURES WILL REMAIN NEAR SEASONAL NORMS, REACHING AFTERNOON
HIGHS IN THE UPPER 70S TO LOW 80S IN INTERIOR VALLEYS AND LOW TO
MID 60S ALONG THE COAST EACH AFTERNOON. INLAND INTRUSIONS OF LOW
MARINE STRATUS CLOUDS OVERNIGHT WILL LARGELY CLEAR TO SUNNY
SKIES EACH DAY, ASIDE FROM MORE PERSISTENT COASTAL CLOUDS
FRIDAY AND A DEEPER INLAND INTRUSION SATURDAY MORNING AS THE
TROUGH MAKES ITS CLOSEST APPROACH. THESE CLOUDS WILL HELP KEEP
FRIDAY AND SATURDAY A FEW DEGREES COOLER.
BY THE BEGINNING OF NEXT WEEK, A BROAD UPPER-LEVEL RIDGE OVER
THE CENTRAL PLAINS WILL AMPLIFY, PUSHING HEIGHTS ALOFT UPWARD
LOCALLY. THIS WILL RESULT IN WARMER TEMPERATURES MONDAY AND
TUESDAY, WITH AFTERNOON HIGHS MOST LIKELY IN THE MID 80S TO
AROUND 90 DEGREES WITHIN INLAND VALLEYS AND MID 60S TO NEAR 70
DEGREES ON THE COAST. TEMPERATURES LOOK TO PEAK ON TUESDAY, WITH
THE CHANCES TO EXCEED 90 DEGREES REACHING 25-40% ALONG THE I-5
CORRIDOR FROM PORTLAND SOUTHWARD. THE CHANCES FOR MODERATE
HEATRISK REACH 25-45%, HIGHEST IN THE LOWER TUALATIN VALLEY
(BEAVERTON, TIGARD, TUALATIN) AND ADJACENT PORTIONS OF MULTNOMAH
AND CLACKAMAS COUNTIES (PORTLAND, WILSONVILLE, CANBY), WHILE THE
CHANCES OF MAJOR HEATRISK REMAIN LESS THAN 5%. WHILE FORECAST
UNCERTAINTY INCREASES, THE ENSEMBLE CONSENSUS IS THAT ANOTHER
TROUGH WILL MOVE INTO WESTERN CANADA MIDWEEK, PUSHING
TEMPERATURES BACK DOWN A FEW DEGREES ON WEDNESDAY, RESULTING IN
WIDESPREAD MINOR HEATRISK.
LOOKING SLIGHTLY BEYOND THE 7-DAY FORECAST PERIOD, THE ENSEMBLE
CONSENSUS SUGGESTS THE ROBUST INLAND RIDGE MAY RETROGRADE TO
THE WEST, RESULTING IN INCREASED CHANCES FOR MORE HAZARDOUS
HEAT TOWARD THE END OF NEXT WEEK. AT THIS LEAD TIME, THE CHANCES
FOR MAJOR HEATRISK REACH 10-25% FROM SALEM NORTH TO THE LOWER
COWLITZ VALLEY AND PORTLAND EAST THROUGH THE COLUMBIA GORGE FROM
NEXT THURSDAY INTO THE FOLLOWING WEEKEND. -36
AVIATION
ZONAL FLOW ALOFT WILL GIVE WAY TO A WEAK UPPER LEVEL
TROUGH APPROACHING THE REGION. THIS WILL PRODUCE A TYPICAL
SUMMERTIME WIND PATTERN ACROSS THE REGION WITH BREEZY NORTHWEST
WINDS THIS EVENING SUBSIDING OVERNIGHT. THERE IS A HIGH
PROBABILITY (>80% CHANCE) THAT MVFR TO HIGH END IFR CEILINGS WILL
PUSH ONTO THE COAST BETWEEN 03-06Z FRIDAY AND THEN PERSIST THROUGH
AT LEAST 18-21Z SATURDAY. INLAND PENETRATION OF MARINE CLOUDS SHOULD
BE LIMITED, BUT THERE IS A 20-30% CHANCE OF MVFR CEILINGS AT ANY
GIVEN HOUR BETWEEN 14-16Z FRIDAY MATERIALIZING AT KPDX AND KTTD.
KPDX AND APPROACHES...ZONAL FLOW ALOFT WILL GIVE WAY TO A WEAK
UPPER LEVEL TROUGH APPROACHING THE REGION. THIS WILL PRODUCE A
TYPICAL SUMMERTIME NORTHWESTERLY WIND PATTERN WITH AN INCREASE
IN WINDS THIS EVENING AND VFR CONDITIONS THROUGH AT LEAST 12Z
FRIDAY. THERE IS A 20-30% CHANCE OF MVFR CEILINGS PUSHING
UP THE COLUMBIA RIVER AND REACHING THE TERMINAL AROUND 14-16Z
FRIDAY.
MARINE
HIGH PRESSURE OVER THE WATERS TODAY WILL MAINTAIN
BREEZY NORTH TO NORTHWEST WINDS THROUGH THIS EVENING. GUSTS UP
TO 20 KT WILL BE POSSIBLE SOUTH OF CAPE FOULWEATHER. A WEAK
COLD FRONT WILL MOVE ACROSS THE WATERS ON FRIDAY, ULTIMATELY
DISRUPTING THE HIGH PRESSURE AND DECREASING WINDS ACROSS THE
WATERS. HIGH PRESSURE EFFETELY REBUILDS OVER THE COASTAL WATERS
THROUGH THE WEEKEND, RETURNING NORTHERLY WINDS LATER SATURDAY
AND INCREASING PRESSURE GRADIENTS ON SUNDAY, RETURNING CHANCES
FOR GUSTS UP TO 25 KT. SEAS ARE EXPECTED TO REMAIN AROUND 4 TO 6
FT AS RELATIVELY BENIGN CONDITIONS PERSIST THROUGH THE WEEKEND
AND INTO THE START OF NEXT WEEK. /DH
PQR WATCHES/WARNINGS/ADVISORIES
OR...NONE.
WA...NONE.
PZ...NONE.
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