649  
FXUS66 KPDT 102322  
AFDPDT  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PENDLETON OR  
422 PM PDT SUN MAY 10 2026  
   
KEY MESSAGES  
 
- CONDITIONS WILL REMAIN DRY AND WARM INTO THE MIDWEEK  
 
- BREEZY CONDITIONS TODAY, WITH STRONGEST WINDS IN THE CASCADE  
GAPS  
 
- MOUNTAIN RAIN SHOWER AND ISOLATED THUNDERSTORM CHANCES RETURN  
MIDWEEK  
 
 
   
UPDATE  
 
WINDS HAVE TOUCHED ADVISORY CRITERIA THROUGH THE KITTITAS VALLEY  
THIS AFTERNOON, AND AM ANTICIPATING (80 PERCENT CONFIDENCE) THEM  
TO REMAIN IN THE 25-35 MPH RANGE WITH GUSTS UP TO 45 MPH THROUGH  
EVENING AS A SHORTWAVE TROUGH PASSES OVER THE REGION AND CROSS-  
CASCADE PRESSURE GRADIENTS REMAIN TIGHT (5-7 MB DIFFERENCE  
BETWEEN SEA AND ELN). THUS, HAVE OPTED TO ISSUE A SHORT-  
DURATION WIND ADVISORY, VALID UNTIL 8 PM THIS EVENING.  
 
 
   
DISCUSSION  
 
TONIGHT THROUGH MONDAY: SATELLITE IMAGERY THIS AFTERNOON SHOWS  
A SHORTWAVE FLATTENING A RIDGE OVER THE PACNW, WITH MOSTLY  
CLOUDY CONDITIONS ACROSS THE FORECAST AREA. BREEZY WINDS ARE  
DEVELOPING THROUGH THE CASCADE GAPS AND ALONG THE CASCADE EAST  
SLOPES, WITH WINDS BEGINNING TO PUSH FURTHER EAST INTO THE BASIN  
AND ADJACENT VALLEYS.  
 
THE UPPER RIDGE WILL CONTINUE TO INFLUENCE THE REGION INTO  
TUESDAY, KEEPING CONDITIONS DRY AND WARM ACROSS THE FORECAST  
AREA. THE SHORTWAVE PASSAGE TODAY WILL CONTINUE TO PRODUCE  
BREEZY WINDS LATE INTO THIS EVENING, WITH WINDS GENERALLY  
15-25 MPH AND GUSTS UP TO 40 MPH. TOMORROW, WINDS WILL BECOME  
LIGHT AGAIN WITH CLEAR SKIES.  
 
TUESDAY THROUGH SATURDAY: ENSEMBLE CLUSTER GUIDANCE REMAINS IN  
GOOD AGREEMENT IN THE BREAKDOWN OF UPPER LEVEL RIDGING OVER THE  
REGION TUESDAY, WITH A DEEPER SOUTH TO SOUTHWEST FLOW DEVELOPING  
AS WELL AS A SIGNAL FOR THERMAL TROUGHING TO DEVELOP INTO  
EASTERN AND CENTRAL OR. THIS WILL PROMOTE A MODEST INCREASE IN  
HIGH TEMPERATURES OVER THE REGION, WITH UPPER 80S TO MID 90S IN  
THE LOWER ELEVATIONS, AND MID 70S TO MID 80S IN MOUNTAIN  
VALLEYS. IN ADDITION TO WARMING TEMPERATURES, INSTABILITY ACROSS  
CENTRAL OR AND THE EASTERN MOUNTAINS WILL RESULT IN AN INCREASED  
CUMULUS FIELD ACROSS THE OR CASCADES AND EASTERN MOUNTAINS, WITH  
A VERY LOW CHANCE (<10%) OF AN ISOLATED SHOWER/THUNDERSTORM.  
 
TUESDAY NIGHT THROUGH THURSDAY, UNCERTAINTY REMAINS AROUND THE  
EVOLUTION OF AN UPPER LOW/TROUGH THAT WILL SHIFT INLAND AND  
ACROSS THE PACNW. WHILE THERE IS GOOD AGREEMENT THAT LOW WILL  
KICK INLAND SOMETIME WEDNESDAY, ENSEMBLE MEMBERS ARE SPLIT ON  
THE TRACK OF THE TROUGH AND TIMING OF ITS PASSAGE OVERHEAD.  
SOLUTIONS RANGE FROM A TRACK OVER THE PACNW, WHICH WOULD RESULT  
IN SHOWER CHANCES AND ISOLATED THUNDERSTORM CHANCES ACROSS OUR  
MOUNTAIN ZONES AND ALONG FOOTHILL LOCATIONS, WHILE A SOUTHERN  
TRACK WOULD LIMIT SHOWERS AND THUNDERSTORMS TO CENTRAL AND  
EASTERN OR. TIMING OF THE TROUGH PASSAGE WILL ALSO IMPACT TIMING  
OF SHOWERS/THUNDERSTORMS ACROSS THE AREA, WITH MEMBERS SPLIT ON  
HAVING THE TROUGH OUT OF THE REGION BY THURSDAY EVENING, OR THE  
TROUGH STILL IMPACTING THE AREA THROUGH THURSDAY NIGHT.  
FORECAST CONFIDENCE IN SHOWER/THUNDERSTORM EXTENT IS MODERATE  
(45-55%) WHILE TIMING IS LOW-MODERATE (30-40%).  
 
FRIDAY INTO SATURDAY, ENSEMBLE MEMBERS ARE IN GENERALLY GOOD  
AGREEMENT OF UPPER LEVEL TROUGHING DEVELOPING OFFSHORE FRIDAY,  
THEN KICKING INLAND THROUGH SATURDAY, THOUGH THERE IS  
UNCERTAINTY IN EXACT TIMING THIS FAR OUT. AS THE NEXT TROUGH  
KICKS INLAND, EXPECT ANOTHER ROUND OF MOUNTAIN RAIN SHOWERS TO  
DEVELOP INTO THE WEEKEND. LAWHORN/82  
 
 
   
AVIATION /00Z TAFS THROUGH 00Z TUESDAY/  
 
VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD. WINDS WILL  
INCREASE TO 12-18KTS WITH GUSTS 20-30KTS AT SITES  
DLS/PDT/RDM/BDN/YKM THROUGH THIS MORNING AND AFTERNOON AND  
PERSIST INTO THE MID TO LATE EVENING HOURS. WINDS AT SITES  
ALW/PSC ARE EXPECTED TO INCREASE TO AROUND 12KTS, BUT GUSTS ARE  
EXPECTED TO BE LESS THAN 18KTS AND PERIODIC. OTHERWISE, WINDS  
WILL BECOME LIGHT TONIGHT THROUGH TOMORROW. LAWHORN/82  
 
 
   
FIRE WEATHER  
 
HIGH PRESSURE REMAINS OVER THE REGION WITH DRY AND WARMING  
CONDITIONS INTO LATE TUESDAY. BREEZY WEST TO NORTHWEST WINDS  
WILL CONTINUE TO IMPACT THE REGION TODAY, WITH STRONGEST WINDS  
IN THE CASCADE GAPS. THERE WILL BE INCREASING UNSTABLE  
CONDITIONS ACROSS CENTRAL OR AND THE EASTERN MOUNTAINS TUESDAY.  
MIN RHS TUESDAY WILL GENERALLY BE IN THE TEENS TO MID 20S, WITH  
SINGLE DIGITS IN CENTRAL OR. ISOLATED TO SCATTERED MOUNTAIN  
SHOWERS AND THUNDERSTORMS DEVELOP WEDNESDAY INTO THE WEEKEND.  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
PDT 45 76 47 85 / 0 0 0 0  
ALW 49 76 51 88 / 0 0 0 0  
PSC 49 80 50 91 / 0 0 0 0  
YKM 46 79 49 88 / 0 0 0 0  
HRI 47 79 48 88 / 0 0 0 0  
ELN 43 75 45 83 / 0 0 0 0  
RDM 37 82 45 91 / 0 0 0 0  
LGD 42 77 45 91 / 0 0 0 0  
GCD 42 83 46 95 / 0 0 0 0  
DLS 48 82 52 89 / 0 0 0 0  
 
 
   
PDT WATCHES/WARNINGS/ADVISORIES  
 
WA...WIND ADVISORY UNTIL 8 PM PDT THIS EVENING FOR WAZ026.  
OR...NONE.  
 
 
 
 
 
UPDATE...86  
DISCUSSION...82  
AVIATION...82  
FIRE WEATHER...82  
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