939
FXUS66 KPQR 120600 AAA
AFDPQR
AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PORTLAND OR
1100 PM PDT SAT JUL 11 2026
UPDATED AVIATION DISCUSSION...
SYNOPSIS
LOW-LEVEL ONSHORE FLOW WILL PERSIST THIS WEEKEND INTO
NEXT WEEK, BUT WILL WEAKEN EARLY NEXT WEEK. MEANWHILE, DRY SOUTHWEST
FLOW ALOFT WILL CONTINUE. EXPECT NEAR NORMAL TEMPERATURES FOR THIS
TIME OF YEAR THIS WEEKEND, BEFORE WARMER TEMPERATURES ARRIVE EARLY
NEXT WEEK WITH HIGHS WELL INTO THE 80S FOR INLAND VALLEYS. THE
TEMPERATURE AND PRECIPITATION FORECAST BECOMES MORE UNCERTAIN
WEDNESDAY THROUGH FRIDAY, HOWEVER ODDS ARE LEANING TOWARDS WARMER
THAN NORMAL TEMPERATURES CONTINUING WITH MAINLY DRY CONDITIONS.
SHORT TERM...NOW THROUGH MONDAY NIGHT
THERE IS HIGH CONFIDENCE
LOW-LEVEL ONSHORE FLOW WILL PERSIST THROUGH MONDAY WITH DRY SOUTHWEST
FLOW ALOFT. FORECAST HIGH TEMPERATURES WILL REMAIN NEAR NORMAL FOR
THIS TIME OF YEAR ON SUNDAY WITH MOST INLAND VALLEY LOCATIONS WARMING
INTO THE LOWER 80S. THE HREF ENSEMBLE MEAN FOR CLOUD COVER SUGGESTS
CLOUDS WILL REDEVELOP ALONG THE CASCADES AND FOOTHILLS LATE TONIGHT
BEFORE BACKBUILDING INTO EASTERN PORTIONS OF THE WILLAMETTE VALLEY
AND PORTLAND METRO EARLY SUNDAY MORNING, MAINLY TO THE EAST OF THE
I-5 CORRIDOR. SKIES WILL TREND MOSTLY CLEAR WEST OF I-5, EXCEPT AT
THE COAST WHERE BROKEN CLOUD COVER IS EXPECTED. HOWEVER, DAYTIME
HEATING WILL BRING CLEARING SKIES FOR ALL LOCATIONS SUNDAY AFTERNOON.
CONDITIONS WILL TREND MOSTLY SUNNY THROUGH THE DAY ON MONDAY, ASIDE
FROM SOME MORNING LOW CLOUDS ALONG THE COAST. THE LACK OF MORNING
CLOUD COVER FOR INLAND AREAS ON MONDAY IS A RESULT OF WEAKENING
ONSHORE FLOW, AS THE SURFACE PRESSURE GRADIENT BETWEEN NORTH BEND, OR
AND SPOKANE, WA IS FORECAST TO WEAKEN TO +1 TO +2 MB. NOTE THAT A
PRESSURE GRADIENT OF +4 TO +7 MB OR STRONGER IS TYPICALLY THE
STRENGTH NEEDED BETWEEN THESE TWO LOCATIONS FOR LOW MARINE CLOUDS TO
FILL INTO THE WILLAMETTE VALLEY. DUE TO THE LACK OF MORNING CLOUDS
INLAND, TEMPERATURES WILL BE NOTICEABLY WARMER ON MONDAY WITH
AFTERNOON HIGHS AROUND 85-89 DEGREES FOR INLAND VALLEYS. MEANWHILE,
ONSHORE WINDS AT THE COAST WILL KEEP TEMPERATURES RELATIVELY COOLER
AT AROUND 65-70 DEGREES. TOTAL MODEL SPREAD FOR TEMPERATURES ON
MONDAY IS VERY SMALL, SUGGESTING CONFIDENCE IS HIGH THESE
TEMPERATURES WILL MATERIALIZE.
THE ONLY OTHER THING WORTH NOTING IS THE POTENTIAL FOR HAZY SKIES IN
THE CASCADES OF EASTERN LANE COUNTY SATURDAY AFTERNOON/EVENING AND
SUNDAY AFTERNOON/EVENING DUE TO SMOKE COMING FROM A WILDFIRE BURNING
IN NORTHWEST JACKSON COUNTY BETWEEN WIMER, OR AND SHADY GROVE, OR.
THIS WILDFIRE IS NAMED THE EAST EVANS CREEK FIRE. THE RRFS SMOKE
MODEL BACKS UP THIS EXPECTATION, WITH VERTICALLY INTEGRATED SMOKE
VALUES INCREASING TO NEAR 100 MG/M^2 NEAR THE CASCADE CREST.
FORTUNATELY, SMOKE ALOFT IS NOT EXPECTED TO MIX DOWN TO THE SURFACE
IN EASTERN LANE COUNTY. -23
LONG TERM...TUESDAY THROUGH FRIDAY NIGHT
THERE IS HIGH CONFIDENCE
FOR MOSTLY SUNNY SKIES ON TUESDAY WITH HIGH TEMPERATURES RANGING
BETWEEN 85-90 DEGREES FOR INLAND VALLEYS AND 65-70 DEGREES AT THE
COAST. THE ONLY FEATURE WORTH NOTING ON TUESDAY IS A POTENTIAL WEAK
UPPER LEVEL IMPULSE THAT IS SET TO MOVE SOUTHWEST TO NORTHEAST ALONG
AND EAST OF THE OREGON CASCADE CREST. THIS WILL BRING A 15-25% CHANCE
OF SHOWERS AND THUNDERSTORMS IN FAR EASTERN LANE COUNTY NEAR THE
CASCADE CREST TUESDAY AFTERNOON AND EVENING, WITH RELATIVELY HIGHER
CHANCES EAST OF THE CREST. GIVEN CLOUD LAYER WINDS WILL BE
SOUTHWESTERLY, ANY CONVECTION THAT DOES DEVELOP NEAR THE CREST WOULD
MOVE EAST OF THE CREST.
THE OVERALL WEATHER PATTERN BECOMES MORE UNCERTAIN WEDNESDAY THROUGH
FRIDAY, ESPECIALLY IN REGARDS TO THE TEMPERATURE AND PRECIPITATION
FORECAST. THIS STEMS FROM DIFFERENCES AMONGST MODEL ENSEMBLE GUIDANCE
REGARDING THE STRENGTH, TRACK, AND EVOLUTION OF A CLOSED UPPER LOW
OVER THE FAR NORTHEAST PACIFIC. THIS UNCERTAINTY CAN BE VISUALIZED
WELL VIA THE LREF 90TH-10TH PERCENTILE FOR 500 MB HEIGHTS, WHICH
SHOWS A LARGE AREA OF HEIGHT DIFFERENCES AROUND 15 DAM, FOCUSED OVER
THE NORTHEAST PACIFIC AND COASTAL WATERS. THE LARGEST DEGREE OF
UNCERTAINTY IN THE UPPER AIR PATTERN BEGINS WEDNESDAY AND LINGERS
THROUGH THURSDAY. IF THIS UPPER LEVEL LOW MOVES TO OUR NORTH AND IS
FOCUSED OVER B.C. AND/OR NORTHWEST WASHINGTON, CONDITIONS WILL TREND
DRY WITH NEAR AVERAGE TO WARMER THAN AVERAGE TEMPERATURES OVER
NORTHWEST OR AND SOUTHWEST WA. IF THIS LOW MOVES DIRECTLY OVER
WESTERN OR AND SOUTHWEST WA, TEMPERATURES WILL TREND SLIGHTLY BELOW
AVERAGE WITH INCREASING CHANCES FOR RAIN SHOWERS.
ENSEMBLE GUIDANCE CURRENTLY FAVORS AN UPPER LOW TRACK THAT IS FURTHER
TO THE NORTH, RESULTING IN FORECAST TEMPERATURES IN THE MID TO UPPER
80S ON WEDNESDAY AND THURSDAY WITH ONLY A 5-15% CHANCE OF SHOWERS.
HOWEVER, TOTAL MODEL SPREAD FOR HIGH TEMPERATURES ON BOTH DAYS IS
OVER 20 DEGREES, WITH HIGHS RANGING ANYWHERE FROM THE MID 70S TO MID
90S. THEREFORE, IT IS CLEAR THE FORECAST IS QUITE UNCERTAIN MID TO
LATE IN THE WEEK. CONFIDENCE INCREASES FOR DRY WEATHER ON FRIDAY,
HOWEVER THE TEMPERATURE FORECAST REMAINS UNCERTAIN WITH THE NBM
10TH-90TH PERCENTILE FOR HIGHS RANGING FROM THE LOWER 80S TO UPPER
90S FOR INLAND VALLEYS. -23
AVIATION
A WEAK TROUGH CONTINUES TO MOVE NORTHEAST AWAY FROM
THE AIRSPACE, CONTINUING SOUTHWESTERLY FLOW ALOFT. WHILE SOME
STRATUS MAY BACK BUILD ALONG THE CASCADES TONIGHT, EXPECT VFR
CONDITIONS AT ALL INLAND TERMINALS THROUGH THE TAF PERIOD (LESS
THAN 20% CHANCE OF MVFR CIGS BETWEEN 08-15Z SUN). AS FOR THE
COAST, THERE IS LOW CONFIDENCE FOR CEILING CONDITIONS BETWEEN 07Z
AND 18Z SUN, WITH A 40-50% CHANCE OF MVFR CIGS AT ALL COASTAL
TERMINALS. WHILE MOST COASTAL TERMINALS ARE CURRENTLY VFR, LOW
SCATTERED CLOUDS HAVE STARTED TO DEVELOP SO MVFR CIGS MAY DEVELOP
BY 07-08Z SUN. BY 15-18Z SUN, COASTAL TERMINALS WILL RETURN TO VFR
AND REMAIN SO THROUGH THE REMAINDER OF THE TAF PERIOD. EXPECT
WINDS TO REMAIN GENERALLY LIGHT AND VARIABLE OVERNIGHT, THEN
INCREASE TO AROUND 5-10 KT AND SHIFT NORTHWESTERLY AROUND 18Z SUN.
COASTAL TERMINALS WILL SEE A BIT STRONGER WINDS, GENERALLY 12-17
KT WITH GUSTS UP TO 25 KT BETWEEN 18Z SUN AND 04Z MON.
KPDX AND APPROACHES...VFR WITH NORTHWESTERLY WINDS, LIGHT
OVERNIGHT THEN INCREASING TO AROUND 10 KT BY 18-21Z SUN. 10-20%
CHANCE OF MVFR CIGS BETWEEN 08-14Z SUN. ~12
MARINE
A WEAK AREA OF LOW PRESSURE SITS OFFSHORE AND WILL
SLOWLY MOVE INLAND OVERNIGHT. THE LOW PRESSURE CENTER IS ENHANCING
THE ALREADY PRESENT NORTHWESTERLY SWELL, AND WINDS ARE INCREASING
AROUND BUOY 46029 WHERE GUSTS UP TO 17 KT HAVE BEEN REPORTED.
THESE CONDITIONS ARE NOT NECESSARILY GOING TO AMPLIFY
SIGNIFICANTLY TONIGHT BUT WE WILL SEE A RESPONSE ON SUNDAY.
THE LOW WILL SHIFT INLAND CAUSING SEAS TO SLOWLY BUILD TO 7-9 FT
AT 8-9 SECONDS, AND WINDS WILL BEGIN TO AMPLIFY. WILL SEE SMALL
CRAFT ADVISORY LEVEL WINDS IN THE CENTRAL AND SOUTHERN WATERS AS
EARLY AS LATE SUNDAY MORNING, AND THEN THOSE SPEEDS WILL MOVE
NORTH INCORPORATING THE NORTHERN WATERS. OVERALL, THEY ARE GOING
TO BE HOVERING RIGHT ALONG THE THRESHOLD OF 15 TO 20 KT WITH GUSTS
UP TO 25 KT SO WINDS MAY NOT BE AS WIDESPREAD. HOWEVER, GIVEN THE
INCOMING PATTERN AND THE HIGH PRESSURE DEVELOPING COMBINED WITH
THE DIURNAL COMPONENT TO OUR WIND, THERE IS ENOUGH CONFIDENCE FOR
AT LEAST THIS ADVISORY.
WINDS WILL EASE TO BELOW THRESHOLDS ON MONDAY BUT SEAS WILL REMAIN
AROUND 7-8 FT AT 8 SECONDS THUS LEAVING CHOPPIER CONDITIONS.
BECAUSE OF THIS, COULD SEE THE ADVISORY EXTENDED, BUT AT THIS TIME
CONFIDENCE IS TOO LOW TO PROJECT TOO FAR INTO THE FUTURE GIVEN
ITS MARGINAL NATURE. -27
PQR WATCHES/WARNINGS/ADVISORIES
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FROM 11 AM SUNDAY TO 2 AM PDT MONDAY FOR
PZZ251-271.
SMALL CRAFT ADVISORY FROM 11 AM SUNDAY TO 11 AM PDT MONDAY FOR
PZZ252-253-272-273.
WWW.WEATHER.GOV/PORTLAND
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