322
FXUS66 KPDT 190506
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
906 PM PST SUN JAN 18 2026
UPDATED AVIATION
PREV DISCUSSION
/ISSUED 211 PM PST SUN JAN 18 2026/
DISCUSSION...SATELLITE SHOWS THE STRATUS ENCOMPASSING THE LOWER
ELEVATIONS OF THE PDT REGION CONTINUING THROUGH TODAY AND MORE
THAN LIKELY (70-80 PERCENT CHANCE) TO PERSIST UNTIL MONDAY. AS WE
CONTINUE TO BE DOMINATED BY HIGH PRESSURE IN THE SYNOPTIC SCALE,
WE'LL CONTINUE TO SEE FREEZING FOG FORMATION ACROSS THE LOWER
VALLEYS (ESPECIALLY IN SHELTERED REGIONS). CURRENTLY, THERE'S
STILL AN AREA OF DENSE FOG AROUND CABBAGE HILL, POVERTY FLATS, AND
DEADMAN PASS WITH LESS THAN A QUARTER OF A MILE VISIBILITY
READINGS. THIS WILL PERSIST THROUGH THE EARLY TO MID AFTERNOON
HOURS, BUT WE'LL LIKELY (70-90 PERCENT CHANCE) SEE ANOTHER
FORMATION OF FREEZING FOG DEVELOP IN AREAS BELOW 2500-3000 FEET
OVERNIGHT. ANOTHER (FREEZING) DENSE FOG ADVISORY IS LIKELY TONIGHT
(60-80 PERCENT CHANCE) FOR THE FOOTHILLS OF THE BLUES, KITTITAS
VALLEY, CENTRAL OREGON, AND NORTH CENTRAL OREGON. AIR STAGNATION
IS ANOTHER HIGHLIGHT THAT WILL CONTINUE THROUGH 4PM TUESDAY, WITH
POOR AIR QUALITY CONDITIONS AND VERY LIGHT WINDS THROUGH THE LOWER
ELEVATIONS.
WE'LL GET BETTER MIXING HEADING INTO MID-WEEK WITH THE RIDGE
WEAKENING AND A SHORTWAVE PASSING THROUGH CALIFORNIA, THE STRATUS
IS PROBABLY (50-70 PERCENT CHANCE) GOING TO BE EATEN UP WITH THE
SUBSIDENCE FADING AWAY. WITH THAT, WE'LL SEE OUR POP CHANCES GO UP
TO 20-40 PERCENT CHANCES HEADING INTO FRIDAY AND THROUGH THE
WEEKEND AS A COLD FRONT APPROACHES FROM WASHINGTON AND CANADA
BEFORE STALLING OVER THE AREA. SNOW LEVELS WILL BE MUCH LOWER IN
THIS PERIOD, DROPPING TO AROUND 2000-3000 FEET (AND AS LOW AS
1500 FEET IN PARTS OF THE WASHINGTON COLUMBIA BASIN). THIS WILL BE
A MAINLY SNOW DOMINATED SYSTEM, WITH THE HEAVIEST AREAS IN THE
MOUNTAIN REGION RECEIVING UP TO 3 TO 5 INCHES THROUGH THE WEEKEND
(30-50 PERCENT CONFIDENCE) AND PARTS OF THE FOOTHILLS OF THE BLUE
MOUNTAINS (AND SOME PARTS OF THE BASIN CLOSE TO THE FOOTHILLS)
GETTING UP TO A QUARTER INCH OF SNOW (20-40 PERCENT CONFIDENCE).
OF COURSE, THIS IS ALL THROUGH DAY 5-7 CURRENTLY AND GUIDANCE
COULD CHANGE, BUT THE OVERALL TONE AFTER THE CURRENT RIDGE
DEPARTS, IS THAT WE'LL AT LEAST SEE SOME AREAS OF LIGHT TO
MODERATE MOUNTAIN SNOW (MOSTLY LIGHT) AND SLIGHT CHANCES OF A
DUSTING IN PARTS OF THE FOOTHILLS.
AVIATION...06Z TAFS...CONDITIONS CONTINUE TO RANGE FROM MVFR TO
LIFR ACROSS THE REGION. AS THE HIGH PRESSURE LINGERS OVERHEAD AND
WINDS REMAIN LIGHT, THERE ARE NO CHANCES OF MIXING WHICH IS WHAT
IS KEEPING THE STRATUS AND FOG. EXPECT ALL SITES TO REMAIN MVFR
OR WORSE THROUGH THE FORECAST PERIOD. HOWEVER, MODELS ARE
SUGGESTING SLIGHT CLEAR OUT TOMORROW AFTERNOON, BUT SHOWS THE
CLOUD DECKS TO REFORM AGAIN OVERNIGHT.
PRELIMINARY POINT TEMPS/POPS
PDT 24 36 23 36 / 0 0 0 0
ALW 26 36 25 35 / 0 0 0 0
PSC 25 38 24 38 / 0 0 0 0
YKM 23 39 23 40 / 0 0 0 0
HRI 25 37 24 37 / 0 0 0 0
ELN 21 36 22 37 / 0 0 0 0
RDM 18 43 20 49 / 0 0 0 0
LGD 22 48 25 45 / 0 0 0 0
GCD 26 53 27 51 / 0 0 0 0
DLS 27 41 26 40 / 0 0 0 0
PDT WATCHES/WARNINGS/ADVISORIES
OR...AIR STAGNATION ADVISORY UNTIL 4 PM PST TUESDAY FOR ORZ041-044-
507-508-510-511.
WA...AIR STAGNATION ADVISORY UNTIL 4 PM PST TUESDAY FOR WAZ024-
026>029-521.
SHORT TERM...95
LONG TERM....95
AVIATION...90
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page