001
FXUS66 KPQR 050434 AAA
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
934 PM PDT TUE AUG 4 2026
UPDATED AVIATION DISCUSSION
SYNOPSIS
HOT, DRY, AND SMOKY CONDITIONS ARE ON TAP FOR
SOUTHWESTERN WASHINGTON AND NORTHWEST OREGON THROUGH MIDWEEK.
HIGH TEMPERATURES FOR MOST INLAND VALLEY LOCATIONS PEAK IN THE
LOW TO UPPER 90S THROUGH THURSDAY, THOUGH WILDFIRE SMOKE MAY
DAMPEN TEMPERATURES FROM RISING BY A FEW DEGREES. HOWEVER,
TEMPERATURES WILL STILL BE WARM ENOUGH FOR WIDESPREAD MODERATE
TO LOCALLY MAJOR HEATRISK IMPACTS. TEMPERATURES BEGIN TO TREND
TOUCH COOLER FRIDAY INTO THE WEEKEND WITH THE RETURN OF ONSHORE
FLOW WITH WINDS FROM THE WEST, WHICH WILL ALSO PUSH ANY
LINGERING WILDFIRE SMOKE AND HAZE BACK EAST OF THE CASCADE
CRESTS. FIRE WEATHER CONCERNS REMAIN IN THE FORECAST THROUGH
WEDNESDAY PRIMARILY FOCUSED IN THE COLUMBIA RIVER GORGE AND
CASCADES.
DISCUSSION...TUESDAY AFTERNOON THROUGH MONDAY
TEMPERATURE
OBSERVATIONS AT 3 PM PDT INDICATE TEMPERATURES ARE AROUND 6 TO
10 DEGREES WARMER THAN 24 HOURS PRIOR, REPORTING IN THE MID 80S
TO LOW 90S FOR ANY INLAND AREAS. DOWNSLOPING EASTERLY WINDS OFF
OF THE COAST RANGE HAVE WARMED SOME COASTAL LOCATIONS SUCH AS
ASTORIA, TILLAMOOK, AND PACIFIC CITY TO THE UPPER 70S TO 80
DEGREES. THIS WARMING TREND IS DUE TO AN AMPLIFYING UPPER LEVEL
RIDGE OF HIGH PRESSURE MOVING FROM THE EASTERN PACIFIC OVER THE
WEST COAST. HOWEVER, TEMPERATURES HAVE NOT WARMED QUITE AS MUCH
TODAY AS PREVIOUSLY FORECAST FOR MOST INLAND LOCATIONS DUE TO
THE INFLUX OF WILDFIRE SMOKE INTO NW OR AND SW WA FROM WILDFIRES
EAST OF THE CASCADES UNDER GENERALLY EASTERLY WIND FLOW.
THE HIGH PRESSURE PEAKS OVER THE REGION WEDNESDAY AND THURSDAY,
WHICH WILL ALLOW TEMPERATURES TO WARM EVEN MORE. CURRENT
FORECAST INDICATES HIGH TEMPERATURES COULD RISE INTO THE MID TO
UPPER 90S EACH DAY FOR THE INTERIOR LOWLANDS. HOWEVER, SMOKE IS
EXPECTED TO CONTINUE IMPACTING THE AREA THROUGH AT LEAST
WEDNESDAY AS THE OFFSHORE FLOW WITH WINDS FROM THE EAST
CONTINUES. THIS MEANS HIGH TEMPERATURES COULD ONCE AGAIN BE
IMPACTED BY THE SMOKE AND MIGHT NOT PEAK QUITE AS HIGH AS
FORECAST. ADDITIONALLY, AS THE UPPER LEVEL RIDGE SLOWLY MOVES
INTO EASTERN OR/WA LATE WEDNESDAY INTO THURSDAY, THE FLOW WILL
BEGIN SHIFTING ONSHORE OR FROM THE WEST. THERE IS SOME
UNCERTAINTY ON EXACTLY WHEN THIS SHIFT WILL HAPPEN, BUT IT WILL
BEGIN PUSHING SMOKE BACK EAST OF THE CASCADES. IF SMOKE CLEARS
OUT EARLIER ON THURSDAY, THEN TEMPERATURES COULD PEAK AT THE
FORECASTED WARMER TEMPERATURES. IF IT DOESN'T CLEAR OUT UNTIL
LATER THURSDAY, SMOKE COULD CONTINUE IMPACTING TEMPERATURES.
REGARDLESS OF THE EXACT OUTCOME OF THE TEMPERATURES, CONDITIONS
WILL BE WARM ENOUGH TO BRING AN INCREASED RISK OF HEAT-RELATED
ILLNESSES. AS SUCH, VARIOUS HEAT ADVISORIES REMAIN IN EFFECT FOR
MOST INLAND VALLEYS THROUGH WEDNESDAY. IN AREAS WITH AIR
QUALITY ADVISORIES IN EFFECT, IT IS RECOMMENDED TO KEEP WINDOWS
AND DOOR SHUT TO PREVENT SMOKE FROM GOING INDOORS. HOWEVER,
THOSE WITHOUT AIR CONDITIONING WHO ARE COUNTING ON OPENING THEIR
WINDOWS AT NIGHT TO HELP COOL DOWN WILL HAVE LESS OPTIONS. IN
THIS SCENARIO, SOMETHING AS SIMPLE AS A LARGE BOX FAN WITH A
DAMP TOWEL DRAPED OVER THE FRONT OF IT CAN BE SURPRISINGLY
EFFECTIVE GIVEN THE DRY AIRMASS IN PLACE. THIS COULD ALSO CAUSE
AN IMPACT EVEN WITH SLIGHTLY LOWER DAYTIME TEMPERATURES AS
HOUSES MAY RETAIN MORE HEAT IF WINDOWS CAN'T BE OPENED TO
ADEQUATELY COOL OFF.
HEADING INTO FRIDAY THE AXIS OF THE BROAD UPPER-LEVEL RIDGE
FEATURE MOVES EAST OF OR/WA, HELPING TO INCREASE ONSHORE FLOW.
THAT SAID, THERE WILL LIKELY BE ENOUGH INFLUENCE FROM THE HIGH
PRESSURE RIDGE ALOFT TO KEEP HIGH TEMPERATURES IN THE LOW 90S
ACROSS THE INLAND VALLEYS INTO SATURDAY. AT LEAST AT THIS POINT
ANY LINGERING WILDFIRE SMOKE SHOULD BE FLUSHED FROM WEST OF THE
CASCADE CRESTS. ONSHORE FLOW IS EXPECTED TO STRENGTHEN FURTHER
OVER THE WEEKEND INTO EARLY NEXT WEEK, ALLOWING TEMPERATURES TO
COOL BACK TO NEAR NORMAL WITH MODERATE TO HIGH CONFIDENCE FOR
MAXIMUM TEMPERATURES RETURNING TO THE LOW TO MID 80S BY
SUNDAY/MONDAY. -03
AVIATION...THROUGH 06Z THU
SMOKY SKIES CONTINUES TO BE THE MAIN
CONCERN ACROSS THE AREA TONIGHT THROUGH WEDNESDAY. AN UPPER LEVEL
RIDGE OF HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE REGION
MAINTAINING WESTERLY FLOW ALOFT. MEANWHILE, EAST TO NORTHEASTERLY
FLOW IN THE LOWER LEVELS WILL CONTINUE TO DRAW WILDFIRE SMOKE
WEST OF THE CASCADES THROUGH AT LEAST WEDNESDAY MORNING. AS OF 04Z
WED, SURFACE OBSERVATIONS CONTINUE TO SHOW REDUCED VIS TO 4-6SM
DUE TO THE SMOKE AND HAZE ACROSS MUCH OF THE WILLAMETTE VALLEY.
IMPROVEMENT TO VFR CONDITIONS IS EXPECTED AS THE SURFACE INVERSION
DEVELOPS AND SMOKE REMAINS MORE ALOFT OVERNIGHT AFTER 06Z. BY LATE
WED MORNING INTO THE AFTERNOON, TEMPERATURES ARE AGAIN EXPECTED
TO WARM INTO THE UPPER 80S TO LOWER 90S, ALLOWING FOR MORE MIXING
OF THE ATMOSPHERE WHICH WOULD LIKELY INCREASE SMOKE TOWARD THE
SURFACE, REDUCING VIS AGAIN TO AROUND 5SM. THE NEAREST MAJOR
WILDFIRE IS THE GRASSHOPPER FIRE EAST OF MT. HOOD, AND AREAS IN
THE VICINITY AND TO THE WEST OF THIS FIRE WILL EXPERIENCE THE
DENSEST SMOKE WITH THE GREATEST VIS IMPACTS. WINDS ARE EXPECTED
TO BECOME MORE WESTERLY IN THE LOWER LEVELS LATER WED AFTERNOON
AND EVENING, WHICH COULD HELP CONDITIONS IMPROVE SLIGHTLY AFTER
00Z THU.
KPDX AND APPROACHES...PREDOMINATELY VFR CONDITIONS ARE EXPECTED
EXCEPT FOR PERIODS OF REDUCED VIS TO 5-6SM DUE TO WILDFIRE SMOKE
IN THE AREA. NORTHWEST WINDS AROUND 3-7 KT EXPECTED, STRONGEST IN
THE AFTERNOON AND EVENING. /DH
MARINE
HIGH PRESSURE OVER THE WATERS WILL MAINTAIN NORTHERLY
WINDS THROUGH THE WEEKEND. SMALL CRAFT ADVISORIES REMAIN IN EFFECT
THROUGH 5 AM WEDNESDAY FOR THE COLUMBIA RIVER BAR AND INNER
WATERS UP TO 10 NM OFFSHORE, AND THROUGH 5 PM WEDNESDAY FOR THE
OUTER WATERS BETWEEN 10-60 NM OFFSHORE. EXPECT NORTHERLY WINDS
WITH GUSTS UP TO 25 KT ACROSS THE WATERS THROUGH LATE TONIGHT, AND
WEAKENING BELOW 20 KT BY LATE WEDNESDAY MORNING. SEAS REMAIN
MOSTLY WIND-DRIVEN AND AROUND 7-9 FT THROUGH TONIGHT, WITH THE
STEEPEST SEAS SOUTH OF CAPE FOULWEATHER. TOMORROW, SEAS IN THE
OUTER WATERS REMAIN STEEP AND CHOPPY AROUND 6-7 FT AT 7-8 SECONDS,
WHICH IS WHY THE SMALL CRAFT ADVISORY EXTENDS INTO WEDNESDAY
AFTERNOON FOR THESE AREAS. WINDS AND SEAS SUBSIDE AFTER TOMORROW,
WITH THE TYPICAL SUMMERTIME PATTERN CONTINUING INTO NEXT WEEK. -10
PQR WATCHES/WARNINGS/ADVISORIES
OR...HEAT ADVISORY UNTIL 11 PM PDT WEDNESDAY FOR ORZ104-105-108>118.
WA...HEAT ADVISORY UNTIL 11 PM PDT WEDNESDAY FOR WAZ204>208.
RED FLAG WARNING UNTIL 8 PM PDT WEDNESDAY FOR WAZ636.
PZ...SMALL CRAFT ADVISORY UNTIL 5 AM PDT WEDNESDAY FOR PZZ210-251>253.
SMALL CRAFT ADVISORY UNTIL 5 PM PDT WEDNESDAY FOR PZZ271>273.
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