766
FXUS66 KPDT 201013
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
313 AM PDT FRI MAR 20 2026
KEY MESSAGES
1. CASCADE RAIN WILL PERSIST THROUGH TODAY (FRIDAY)
2. ABOVE SEASONAL AVERAGE TEMPERATURES REMAIN FRIDAY
3. A SYSTEM WILL BRING TEMPERATURES BACK TO SEASONAL AVERAGE
SATURDAY WITH MOUNTAIN PRECIPITATION CONTINUING
DISCUSSION
CURRENT RADAR SHOWS A FEW RETURNS OVER THE WA
CASCADES AS THE REMNANTS OF THE ATMOSPHERIC RIVER REMAIN OVER
THE AREA. CURRENT GROUND OBSERVATIONS SHOW THAT THE LAST HOUR
THESE RETURNS HAVE ONLY PUT DOWN BETWEEN 0.10-0.12 INCHES OF
RAIN. RAIN IS EXPECTED TO CONTINUE OVER THE MOUNTAINS THROUGH
TODAY (FRIDAY) WITH RAIN ACCUMULATIONS NEARING 0.4-0.8 INCHES
THROUGH 5 AM (70-90% CONFIDENCE). SATURDAY SNOW LEVELS WILL
BEGIN TO DROP STEADILY THROUGH FRIDAY AND SATURDAY BOTTOMING OUT
AT AROUND 2500 FEET. THIS FRONT WILL ALSO BE BRINGING COOLER
TEMPERATURES BACK TO THE MOUNTAINS WITH LIGHT HIGH ELEVATION
MOUNTAIN SNOW WITH ACCUMULATIONS OF 0.10-0.30 INCHES ABOVE 4000
FEET (70-90% CONFIDENCE).
MODELS SHOW AN UPPER LEVEL RIDGE STILL OVER THE REGION. THIS IS WHAT
IS BRINGING THE ABOVE AVERAGE SEASONAL TEMPERATURES. IN HOUSE
COMPARISONS FOR TEMPERATURES SHOWS THAT TEMPERATURES FRIDAY REMAIN
ANYWHERE BETWEEN 20-25 DEGREES ABOVE NORMAL WITH EVEN THE HIGHER
ELEVATIONS SEEING ABOVE AVERAGE TEMPERATURES. MODELS SHOW THE RIDGE
TO REMAIN IN PLACE THROUGH AT LEAST FRIDAY NIGHT AHEAD OF A PATTERN
CHANGE. TEMPERATURES WILL REMAIN ABOVE SEASONAL AVERAGE THROUGH
FRIDAY WITH TEMPERATURES REMAINING IN THE LOW TO MID 70S ACROSS THE
REGION WITH 90-100% OF THE NBM RAW ENSEMBLES IN AGREEMENT. FRIDAY
TEMPERATURES WILL REMAIN IN THE MID 70S FOR MUCH OF THE REGION WITH
AGAIN 90-100% OF THE RAW ENSEMBLES IN AGREEMENT.
FRIDAY NIGHT INTO SATURDAY MODELS ARE IN FIRM AGREEMENT WITH A WEAK
UPPER LEVEL TROUGH SWEEPING INTO THE REGION FOLLOWED BY ZONAL FLOW.
NBM SHOWS SNOW LEVELS TO BEGIN TO DECREASE AS THE SYSTEM MOVES
ACROSS AND TEMPERATURES WILL DECREASE TO NEAR SEASONAL AVERAGE.
MOUNTAIN PRECIPITATION IS EXPECTED WITH THIS SYSTEM WITH VERY LIGHT
(0.01-0.03 INCHES) SNOW ACCUMULATIONS EXPECTED (80-90% CONFIDENCE)
ALONG THE CRESTS OF THE CASCADES WHILE LOWER ELEVATIONS ALONG THE
EAST SLOPES WILL SEE A RAIN/SNOW MIX. MODELS SHOW MUCH OF THE
PRECIPITATION TO PRIMARILY ALONG THE OR CASCADES AND THE FOOTHILLS
OF THE BLUES AND THE BLUE MOUNTAINS SATURDAY WITH RAIN AMOUNTS OF
0.05-0.10 INCHES (60-80% CONFIDENCE). TEMPERATURES WILL DECREASE BY
NEARLY 20 DEGREES SATURDAY WITH LOCALIZED HIGHS IN THE LOW 60S IN
THE BASIN AND MID TO UPPER 50S ELSEWHERE (70-80% CONFIDENCE).
AVIATION /12Z TAFS THROUGH 12Z SATURDAY/
VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD. HIGH
PRESSURE REMAINS OVERHEAD SO CIGS WILL BE MOSTLY 10KFT AND
HIGHER.
WINDS WILL BE THE PRIMARY CONCERN THROUGH THE PERIOD AS ALL
SITES WILL SEE SUSTAINED WINDS OF 10-20 KTS SUSTAINED WITH
GUSTS 20-30 KTS AFTER 17-20Z. WINDS WILL EASE FRIDAY NIGHT TO
LESS THAN 12 KTS. 90
FIRE WEATHER
AN SPS IS OUT FOR ELEVATED FIRE WEATHER
CONDITIONS FOR OCHOCO-JOHN DAY HIGHLANDS AND CENTRAL OR. A
STRONG RIDGE OF HIGH PRESSURE HAS LEAD TO WELL ABOVE AVERAGE
SEASONAL TEMPERATURES AS WELL AS VERY LOW RELATIVE HUMIDITIES
(80-90% CONFIDENCE)FOR PORTIONS OF CENTRAL OR AND THE EASTERN
MOUNTAINS. ADDITIONALLY, DIURNAL WINDS HAVE THE CAPABILITIES OF
REACHING 20 TO 30 MPH GUSTS (50-70% CONFIDENCE). THE COMBINATION
OF DRY CONDITIONS AND ELEVATED WINDS CAN LEAD TO RAPID FIRE
SPREAD. 90
PRELIMINARY POINT TEMPS/POPS
PDT 75 46 58 31 / 10 40 40 0
ALW 74 48 59 35 / 10 50 60 0
PSC 76 47 64 34 / 10 30 20 0
YKM 71 41 59 30 / 30 20 0 0
HRI 76 48 63 32 / 10 30 20 0
ELN 60 37 51 29 / 50 20 0 0
RDM 76 43 58 24 / 0 10 10 0
LGD 78 45 56 29 / 0 30 70 10
GCD 77 46 56 29 / 0 10 50 0
DLS 70 46 60 34 / 20 30 10 0
PDT WATCHES/WARNINGS/ADVISORIES
WA...NONE.
OR...NONE.
DISCUSSION...90
AVIATION...90
FIRE WEATHER...90
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