334
FXUS66 KPQR 250530 AAA
AFDPQR
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PORTLAND OR
930 PM PST TUE FEB 24 2026
UPDATED AVIATION DISCUSSION.
SYNOPSIS
SCATTERED SHOWERS CONTINUE ACROSS THE REGION TODAY,
BECOMING ISOLATED AND LIMITED MAINLY TO FAR NORTHERN OREGON AND
SW WASHINGTON WEDNESDAY THROUGH FRIDAY. RAIN CHANCES THEN SHIFT
TO CENTRAL OREGON SATURDAY INTO SUNDAY AS A WEATHER SYSTEM
MOVING INTO NORTHERN CALIFORNIA BRUSHES CENTRAL OREGON, BUT
CONFIDENCE IS LOW IN DETAILS. DRY WEATHER THEN RETURNS EARLY
NEXT WEEK. CONDITIONS LIKELY REMAIN WITHIN TYPICAL
CLIMATOLOGICAL NORMALS THROUGH THE FORECAST PERIOD WITH NO
SIGNIFICANT WEATHER IMPACTS ON THE HORIZON.
DISCUSSION...TUESDAY AFTERNOON THROUGH MONDAY
THE
ATMOSPHERIC RIVER THAT IMPACTED NW OREGON AND SW WASHINGTON
THROUGH LAST NIGHT SHIFTED INTO S OREGON AND N CALIFORNIA THIS
MORNING AS THE SURFACE FRONT SHIFTED JUST SOUTH OF LANE COUNTY,
LEAVING SCATTERED SHOWERS ACROSS THE AREA IN THE WAKE OF THE
FRONT. SATELLITE IMAGERY TUESDAY AFTERNOON SHOWS THE UPPER
TROUGH THAT FUNNELED THE ATMOSPHERIC RIVER INTO THE PACNW HAS
PINCHED OFF INTO A CUT OFF LOW IN THE EASTERN PACIFIC WEST OF
CALIFORNIA, AND ENSEMBLE GUIDANCE INDICATES THIS LOW WILL
RETROGRADE WEST BEFORE PUSHING BACK EAST TOWARDS THE WEST COAST
LATER THIS WEEK. IN THE MEANTIME, SCATTERED SHOWERS CONTINUE
ACROSS THE REGION THROUGH WEDNESDAY AS A WEAK SHORTWAVE MOVES
FROM THE NORTH THROUGH WASHINGTON AND OREGON. SNOW LEVELS WILL
LOWER TONIGHT WITH THE INCOMING SHORTWAVE, FALLING TO 2500-3500
FT NORTH OF LANE COUNTY AND 3500-4500 FT IN LANE COUNTY BY EARLY
WEDNESDAY MORNING. HOWEVER, WITH SHOWERS BEING SCATTERED AND
LIMITED IN PRECIPITATION, NOT MUCH SNOW IS EXPECTED OVER THE
CASCADES, MAYBE UP TO 2 INCHES IN THE EARLY MORNING HOURS
WEDNESDAY AT WILLAMETTE PASS.
ENSEMBLE GUIDANCE INDICATES FLOW BECOMES ZONAL THURSDAY INTO
FRIDAY THROUGH THE WEEKEND. LOW PRECIPITATION CHANCES CONTINUE
ACROSS THE AREA THROUGH FRIDAY MORNING, MAINLY LIMITED TO THE
NORTH OREGON COAST AND COAST RANGE NORTH OF LINCOLN CITY, FAR
NORTHERN OREGON CASCADES, AND SW WASHINGTON. LIMITED
ACCUMULATION IS EXPECTED. COLDER AIR IS EXPECTED TO BE FUNNELED
INTO THE PACNW BEHIND WEDNESDAY'S SHORTWAVE. THIS ALONG WITH
CLEARING SKIES ACROSS THE MAJORITY OF THE INTERIOR LOWLANDS WILL
LEAD TO COLDER OVERNIGHT TEMPERATURES WEDNESDAY NIGHT WITH A
60-90% CHANCE OF LOW TEMPERATURES THURSDAY MORNING FALLING BELOW
FREEZING IN THE CENTRAL AND SOUTHERN WILLAMETTE VALLEY AND A
40-60% CHANCE FOR THE SW WASHINGTON LOWLANDS. HOWEVER, IF SKIES
DON'T CLEAR AS EXPECTED, LOCATIONS WITH REMAINING CLOUD COVER
WILL NOT COOL QUITE AS MUCH. THERE'S AN OFF CHANCE (~5-10%) AN
ISOLATED SHOWER WANDERS OFF THE COAST RANGE OR WILLAPA HILLS
INTO THE SOUTHWEST WASHINGTON LOWLANDS DURING THIS PERIOD, WHICH
WOULD HAVE THE POTENTIAL TO BE A RAIN/SNOW MIX IF TEMPERATURES
DO LOWER NEAR OR BELOW FREEZING. HOWEVER, A LOT OF VARIABLES
WOULD HAVE TO PERFECTLY ALIGN FOR THIS TO OCCUR. SO WHILE THE
FORECAST MAY INTRODUCE A MENTION OF A SLIGHT CHANCE (15%) FOR
RAIN/SNOW LATE WEDNESDAY NIGHT INTO THURSDAY MORNING, IT IS
EXTREMELY UNLIKELY YOU'LL SEE ANY IMPACTS BELOW 1500-2000FT - IN
FACT YOU'LL BE LUCKY TO SEE ANYTHING AT ALL.
MOSTLY DRY CONDITIONS RETURN FRIDAY AFTERNOON THROUGH SATURDAY
WITH INLAND HIGH TEMPERATURES IN THE 50S AND LOW TEMPERATURES IN
THE MID 30S. UNCERTAINTY INCREASES IN THE FORECAST LATE SATURDAY
INTO LATE SUNDAY. ENSEMBLE GUIDANCE IS IN HIGH AGREEMENT THAT
THE CLOSED LOW REMNANT FROM THE CURRENT LONGWAVE TROUGH IS
SLATED TO MOVE INLAND ALONG THE CALIFORNIA DURING THIS
TIMEFRAME. HOWEVER, UNCERTAINTY REMAINS IN HOW FAR NORTH ALONG
THE CALIFORNIA COAST THIS WILL OCCUR. A TRACK FURTHER NORTH
WOULD YIELD BETTER CHANCES FOR PRECIPITATION. LATEST FORECASTS
INDICATE PRECIPITATION CHANCES LIMITED TO SOUTH OF HIGHWAY 20 IN
OREGON. ADDITIONALLY, PROBABILITIES FOR OVERNIGHT TEMPERATURES
FALLING BELOW FREEZING IN THE INTERIOR LOWLANDS REMAIN LOW TO
MODERATE, MAINLY AROUND 30-60%, DUE TO THE UNCERTAINTY OF THIS
CLOSED LOW. A BIT MORE OF A NORTHERN TRACK WILL LIKELY KEEP LOW
TEMPERATURES ABOVE FREEZING DUE TO CLOUD COVER, BUT A MORE
SOUTHERN TRACK COULD KEEP THE AREA FROM BEING IMPACTED BY THE
CLOSED LOW AND ALLOW FOR THE JET STREAM TO DIP INTO OREGON AND
BRING COLDER TEMPERATURES. EITHER WAY, THE CLOSED LOW IS
EXPECTED TO MOVE EAST BY MONDAY, LEADING TO INCREASING CONFIDENCE
OF DRY WEATHER LATER MONDAY INTO TUESDAY. -03/99
AVIATION
AT 05Z WEDNESDAY, A NEARLY STATIONARY FRONTAL BOUNDARY
WAS DRAPED OVER SOUTHWEST OREGON, WITH LIGHT RAIN SHOWERS
LINGERING OVER NORTHWEST OREGON AND SOUTHWEST WASHINGTON TO THE
NORTH OF THIS BOUNDARY. THESE SHOWERS SHOULD GRADUALLY TAPER OFF
FROM NORTH TO SOUTH BETWEEN 09-15Z WEDNESDAY AS THE AFOREMENTIONED
FRONTAL BOUNDARY FINALLY SAGS SOUTHWARD.
SATELLITE AND SURFACE WEATHER OBSERVATIONS AT 05Z WEDNESDAY DEPICTED
A MESSY MIX OF IFR/MVFR/VFR CIGS AND VISIBILITIES. WHILE
VISIBILITIES ARE GENERALLY STARTING TO IMPROVE AT MOST TERMINALS,
EXPECT CIGS TO FLUCTUATE BETWEEN FLIGHT CATEGORIES TONIGHT BEFORE
TRENDING TOWARDS MAINLY MVFR TOWARDS 15Z WEDNESDAY AND THEN
TOWARDS MAINLY VFR TOWARDS 21Z WEDNESDAY TO 00Z THURSDAY. PATCHY
FOG IS ALSO POSSIBLE TONIGHT WHERE CLOUD COVER SCATTERS OUT,
HOWEVER PROBABILITIES FOR VISIBILITIES BELOW 1 SM ONLY PEAK
BETWEEN 10-25% FOR THE INLAND TERMINALS AND LESS THAN 10% FOR
COASTAL TERMINALS. VARIOUS TEMPO GROUPS WERE USED BETWEEN 06-10Z
WEDNESDAY TO REFLECT CIGS FLUCTUATING BETWEEN FLIGHT CATEGORIES.
KPDX AND APPROACHES...EXPECT LIGHT RAIN SHOWERS TO CONTINUE
THROUGH AT LEAST 09Z WEDNESDAY WITH FLUCTUATING CIGS. ALTHOUGH
CIGS HAVE IMPROVED TO VFR AT THE KPDX TERMINAL, THERE IS A 20-40%
CHANCE CIGS WILL LOWER BACK TO MVFR THRESHOLDS OR LOWER AT ANY
TIME BETWEEN 06-12Z WEDNESDAY, INCREASING TO A 50-60% CHANCE
BETWEEN 12-15Z. CIGS SHOULD SCATTER OUT AND GIVE WAY TO
PREDOMINATELY VFR FLIGHT CONDITIONS BY 00Z THURSDAY (70-75%
CHANCE). THERE IS ALSO A 15-25% CHANCE FOR SURFACE VISIBILITIES
BELOW 1 SM BETWEEN 12-17Z WEDNESDAY, HOWEVER CONFIDENCE IS NOT
HIGH ENOUGH TO INCLUDE THIS IN THE TAF AT THIS TIME. -23
MARINE
SEAS AND WINDS HAVE EASED AS THE MAIN FRONTAL BAND HAS
SHIFTED SOUTHWARD. NORTHERLY WINDS PERSIST AROUND 8-13 KT WITH
ISOLATED GUSTS UP TO 20 KT. SEAS REMAIN BELOW 8 FT FOR MOST BUOYS
WITH MOST SITTING IN THE 5-7 FT RANGE WITH WAVE PERIODS AROUND 8
TO 10 SECONDS. THESE CONDITIONS WILL PERSIST THROUGH FRIDAY.
LOCAL GUIDANCE SHOWS A MIXED BAG OF SWELLS WITH A PRIMARY
NORTHWESTERLY SWELL AND A SOUTHERLY FRESH SWELL THAT THEN
TRANSITIONS INTO A TRUE SECONDARY SWELL. WHILE A COMPLICATED SWELL
ORGANIZATION, WILL SEE WIDESPREAD SEAS RISE TO OR ABOVE 10 FT BUT
THERE IS A LOW PROBABILITY OF SEAS EXCEEDING THAT 10 FT MARK. -27
PQR WATCHES/WARNINGS/ADVISORIES
OR...NONE.
WA...NONE.
PZ...NONE.
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