976
FXUS66 KPQR 201121
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
321 AM PST MON JAN 20 2025
SYNOPSIS
HIGH PRESSURE OVER THE AREA WILL PERSIST THROUGH AT
LEAST THURSDAY AFTERNOON. COLD OVERNIGHT TEMPERATURES EXPECTED
EACH NIGHT WITH BREEZY EASTERLY WINDS. THE COMBINATION OF THESE
TWO FACTORS WILL LEAD TO DANGEROUS WIND CHILL TEMPERATURES WEST
OF THE CASCADES THROUGH MONDAY MORNING. ON THURSDAY, A WEAK
FRONT WILL MOVE OVER THE AREA INCREASING CHANCES FOR LIGHT
PRECIPITATION. AT THIS POINT, NO WINTER WEATHER CONCERNS.
SHORT TERM...NOW THROUGH WEDNESDAY
HIGH PRESSURE OVER THE
AREA WILL KEEP CONDITIONS FAIRLY PERSISTENT OVER THE NEXT
SEVERAL DAYS. OVERNIGHT TEMPERATURES CONTINUE TO DROP WITH
EASTERLY WINDS AND CLEAR SKIES. THE EASTERLY WINDS TO THE NORTH,
AROUND MULTNOMAH COUNTY AND THE COLUMBIA RIVER GORGE, ARE
TRENDING WARMER DUE TO MIXING DOWN WARMER AIR ALOFT.
TEMPERATURES IN THE GREATER PORTLAND/VANCOUVER-METRO AREA ARE
HOVERING AROUND 35-40 DEGREES F. SHIFTING SOUTHWARD,
TEMPERATURES ARE MUCH COOLER WITH LOWS IN THE LOWER 20S. THE
COMBINATION OF COLD OVERNIGHT TEMPERATURES AND GUSTY WINDS IS
CAUSING THE AMBIENT AIR TEMPERATURE (WHAT IT "FEELS LIKE"), TO
DROP TO THE TEENS. WITH THESE WIND CHILLS, HAVE CONTINUED THE
COLD WEATHER ADVISORY THROUGH THE REMAINDER OF THE MORNING. AS
THE SUN RISES, WILL SEE STEADY WARMING.
MINIMAL CHANGE IN THE COMING DAYS ASIDE FROM SOME CLOUD COVER
WHICH WILL MOVE IN ON TUESDAY. SOME HIGH CLOUDS WILL KEEP
TEMPERATURES SLIGHTLY WARMER AND WINDS WILL EASE OUTSIDE OF THE
GORGE. WITH LESS WIND, APPARENT TEMPERATURES WILL SIT JUST ABOVE
CRITICAL THRESHOLDS FOR ANY ADVISORIES. WILL CONTINUE TO MONITOR
THOUGH IF WINDS INCREASE FURTHER. -MUESSLE
LONG TERM...THURSDAY THROUGH SUNDAY
THE FIRST PATTERN SHIFT
OF THE WEEK ARRIVES ON THURSDAY AFTERNOON. A FRONT FROM THE GULF
OF ALASKA WILL SHIFT SOUTHWARD THROUGH THE DAY. THERE ARE
INCREASED CHANCES FOR PRECIPITATION BUT THE HIGHEST
ACCUMULATIONS WILL BE OBSERVED ALONG THE MOUNTAINS. COLD AIR
WILL STILL BE IN PLACE AT THE SURFACE WITH 850 MB TEMPERATURES
AROUND -4 DEG C. WHILE PRECIPITATION WILL BE FAIRLY LIGHT, IF A
STRONGER BAND OF PRECIPITATION SETS UP, COULD SEE COLDER AIR MIX
DOWN FROM ALOFT AND BRING A BIT OF SNOWFALL TO THE COLUMBIA
RIVER GORGE. AT THIS POINT, NO CONCERNS FOR SIGNIFICANT WINTER
WEATHER ON THURSDAY INTO FRIDAY. MOVING INTO THE WEEKEND, THE
500 MB HEIGHTS SHOW A CONSISTENT TROUGHING PATTERN. SENSIBLE
WEATHER WISE THOUGH, IT IS A MIXED BAG OF DRY OR WETTER
OUTCOMES. -MUESSLE
AVIATION
HIGH PRESSURE REMAINS IN CONTROL OF THE AREA AND WILL
SUPPORT VFR CONDITIONS THROUGH THE TAF PERIOD. OFFSHORE WINDS FOR
MOST OF THE AREA EXCEPT THE CENTRAL/SOUTHERN WILLAMETTE VALLEY
WHICH WILL SEE LIGHT NORTHERLY WINDS. EASTERLY WINDS WILL BE
STRONGEST THROUGH THE COLUMBIA RIVER GORGE AND AROUND THE METRO
WITH GUSTS THROUGH THE GORGE TO 30-35 KT EXPECTED TODAY. SURFACE
CONDITIONS WILL CONTINUE TO DRY UNDER HIGH PRESSURE, KEEPING FOG
AND STRATUS AT BAY.
COLD TEMPS AND CLEAR SKIES WILL SUPPORT FROSTY CONDITIONS ON THE
GROUND.
PDX AND APPROACHES...CLEAR SKIES AND VFR CONDITIONS EXPECTED
THROUGH THE TAF PERIOD AT PDX, EASTERLY WINDS 10-15 KT WITH GUSTS
TO AROUND 20 KTS EXPECTED THROUGH MUCH OF TODAY. GUSTY EAST WINDS
WITH GUSTS UP TO 25 KT AT KTTD. -BATZ
MARINE
HIGHER PRESSURE OVER LAND VS THE WATERS WILL LEAD TO AN
OFFSHORE PRESSURE GRADIENT WITH EASTERLY WINDS OVER THE WATERS
THROUGH TODAY. THE SURFACE PRESSURE GRADIENT WEAKENS TONIGHT AND
TUESDAY AS A WEAK DISTURBANCE MOVES OVER THE AREA FOR A PERIOD OF
LIGHT AND VARIABLE WINDS. HIGH PRESSURE REBUILDS OVER THE NE
PACIFIC WEDNESDAY RETURNING NORTH WINDS THROUGH AT LEAST FRIDAY.
THERE IS A GOOD CHANCE (40-80%) THAT WIND GUSTS OF 21 KT RETURN TO
THE WATERS LATE THURSDAY THROUGH FRIDAY BUT STILL TOO FAR OUT TO
ISSUE ANY SORT OF HEADLINE.
A SERIES OF NW SWELLS WILL MAINTAIN 6-8 FT SEAS THROUGH THURSDAY
NIGHT. A LARGER SWELL IS EXPECTED FRIDAY WHEN THERE IS A 40-60%
CHANCE OF SEAS BUILDING BETWEEN 9 AND 12 FEET. -BATZ/TJ
PQR WATCHES/WARNINGS/ADVISORIES
OR...COLD WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR
ORZ101>125.
WA...COLD WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR
WAZ201>210.
PZ...NONE.
WWW.WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA:
WWW.FACEBOOK.COM/NWSPORTLAND
X.COM/NWSPORTLAND
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