129  
FXUS66 KPDT 241057  
AFDPDT  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PENDLETON OR  
357 AM PDT SUN MAY 24 2026  
   
KEY MESSAGES
 
 
- WARM, DRY CONDITIONS TODAY  
 
- A LOW-PRESSURE SYSTEM AND COLD FRONT ARE SLATED TO ARRIVE  
MONDAY AFTERNOON AND EVENING, USHERING IN WIDESPREAD BREEZY TO  
WINDY WESTERLY WINDS AND A SLIGHT CHANCE OF THUNDERSTORMS  
 
- SHOWER AND THUNDERSTORM CHANCES CONTINUE TUESDAY THROUGH THE  
WEEK, BUT UNCERTAINTY REMAINS IN FORECAST DETAILS  
 

 
   
DISCUSSION
 
ABOVE-NORMAL TEMPERATURES AND DRY CONDITIONS WILL  
CONTINUE TODAY AS THE REGION REMAINS UNDER ZONAL FLOW ALOFT.  
LOCALLY BREEZY WINDS COUPLED WITH WIDESPREAD LOW AFTERNOON  
RELATIVE HUMIDITY WILL LEAD TO LOCALLY ELEVATED FIRE WEATHER  
CONCERNS, BUT NO HEADLINES ARE IN EFFECT.  
 
THE NEXT FEATURE THAT WILL DRIVE OUR WEATHER MONDAY THROUGH THE  
REMAINDER OF THE WEEK, A DEEPENING CLOSED LOW, IS VISIBLE IN  
WATER VAPOR IMAGERY, LOCATED OFFSHORE IN THE VICINITY OF THE  
GULF OF ALASKA. ENSEMBLE NWP GUIDANCE IS UNANIMOUS IN TAKING THE  
CLOSED LOW SOUTHEAST ALONG THE PACIFIC COAST INTO MONDAY.  
ENSEMBLE SOLUTIONS EXHIBIT SOME SUBTLE DIFFERENCES WITH REGARD  
TO TIMING AND LOCATION/TRACK AS IT BEGINS TO MOVE ONSHORE  
MONDAY, BUT CONFIDENCE IN THE LOW AND ITS ATTENDANT SURFACE COLD  
FRONT PROVIDING A PATTERN CHANGE LATE MONDAY IS VERY HIGH (99  
PERCENT).  
 
MONDAY, FLOW ALOFT WILL TURN SOUTHWESTERLY, AND WIDESPREAD  
BREEZY WINDS COUPLED WITH LOW RELATIVE HUMIDITY ARE FORECAST  
ACROSS CENTRAL OREGON AND THE EASTERN MOUNTAINS PRIOR TO THE  
ARRIVAL OF THE COLD FRONT MENTIONED IN THE PREVIOUS PARAGRAPH.  
THIS WILL LEAD TO SOME ELEVATED FIRE WEATHER CONCERNS, BUT NONE  
OF OUR FIRE WEATHER ZONES HAVE BEEN DECLARED READY FOR RED FLAG  
WARNINGS YET SO NO HEADLINES ARE CURRENTLY PLANNED. TEMPERATURES  
WILL BE WELL ABOVE NORMAL FOR THE AFOREMENTIONED REGION AS WELL  
AS PORTIONS OF THE COLUMBIA BASIN AND BLUE MOUNTAIN FOOTHILLS.  
 
BY LATE MONDAY, THE UPPER LOW AND ATTENDANT SURFACE COLD FRONT  
ARE SLATED TO ARRIVE, WITH THE FRONT SWEEPING FROM WEST TO EAST  
FROM AFTERNOON THROUGH LATE EVENING. NBM PROBABILITIES OF  
EXCEEDANCE SUGGEST MEDIUM-HIGH CHANCES (40-85 PERCENT) OF  
REACHING OR EXCEEDING ADVISORY-LEVEL WIND GUSTS ACROSS ALL OF  
OUR NON-MOUNTAIN ZONES. MOREOVER, THE NBM IS ADVERTISING A CHANCE  
(LOCALLY 30-60 PERCENT) OF EXCEEDING WARNING-LEVEL GUSTS (58 MPH  
OR GREATER) ACROSS WIND-PRONE PORTIONS OF THE BLUE MOUNTAIN  
FOOTHILLS AS WELL AS CENTRAL OREGON, THE SIMCOE HIGHLANDS, THE  
YAKIMA VALLEY, AND THE EASTERN COLUMBIA RIVER GORGE. THINK THE  
LATTER PROBABILITIES ARE TOO HIGH RELATIVE TO WHAT RAW GUIDANCE  
IS SHOWING; NONETHELESS, WIND HEADLINES MAY BE NEEDED.  
 
IN ADDITION TO THE STRONG, GUSTY WINDS MONDAY AFTERNOON AND  
EVENING, THERE IS A LOW (5-15 PERCENT) CHANCE OF HIGH-BASED  
SHOWERS AND THUNDERSTORMS ACROSS THE COLUMBIA BASIN, BLUE  
MOUNTAIN FOOTHILLS, AND BLUE MOUNTAINS (MAINLY THE NORTHERN  
BLUES). ALL DETERMINISTIC GUIDANCE IS HIGHLIGHTING SOME ELEVATED  
INSTABILITY, AND SYNOPTIC-SCALE FORCING APPEARS TO BE SUPPORTIVE  
OF KICKING OFF SOME SHOWERS OR THUNDERSTORMS GIVEN A SUFFICIENT  
MID-LEVEL MOISTURE FIELD. THE NBM HAS YET TO INCLUDE A MENTION  
OF THESE SHOWERS AND THUNDERSTORMS IN THE FORECAST PRIOR TO 5PM  
PDT MONDAY, BUT DOES INCLUDE SHOWERS ACROSS THE REGION AFTER 5PM  
AS THE FRONT MOVES THROUGH.  
 
TUESDAY THROUGH THE REMAINDER OF THE WEEK, SHOWER AND  
THUNDERSTORM CHANCES WILL CONTINUE, TIED TO THE LOCATION OF THE  
UPPER-LEVEL LOW AS IT TRACKS INLAND ACROSS THE GREAT BASIN  
(LIKELY TUESDAY THROUGH THURSDAY) AND EVENTUALLY EJECTS NORTH-  
NORTHEAST ACROSS THE GREAT BASIN, PACIFIC NORTHWEST, OR ROCKIES  
BY FRIDAY AND SATURDAY. ENSEMBLE CLUSTER ANALYSIS SUGGESTS A  
PRETTY EVEN SPLIT (40-60 PERCENT, VARYING BY DAY) REGARDING THE  
LOW BEING IN A LOCATION SUPPORTIVE (OR ALONG A SUPPORTIVE TRACK)  
FOR SHOWERS, THUNDERSTORMS, AND NOTABLE SPRING PRECIPITATION  
FOR THE FORECAST AREA.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z MONDAY/
 
VFR CONDITIONS ARE  
FORECAST FOR THE NEXT 24 HOURS, WITH SKY COVER RANGING FROM SKC  
TO BKN CIRRUS. WINDS WILL BE DIURNALLY DRIVEN, STRONGEST DURING  
THE LATE MORNING THROUGH EVENING HOURS.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
PDT 82 51 83 44 / 0 0 0 50  
ALW 82 57 84 48 / 0 0 0 40  
PSC 86 54 86 46 / 0 0 0 40  
YKM 85 53 78 44 / 0 0 0 10  
HRI 84 54 83 45 / 0 0 0 40  
ELN 77 49 73 40 / 0 0 0 10  
RDM 84 46 81 34 / 0 0 0 20  
LGD 82 48 87 43 / 0 0 10 60  
GCD 84 46 87 40 / 0 0 0 70  
DLS 83 54 77 46 / 0 0 0 10  
 

 
   
PDT WATCHES/WARNINGS/ADVISORIES
 
 
WA...NONE.  
OR...NONE.  
 

 
 

 
 
DISCUSSION...86  
AVIATION...86  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab OR Page
The Nexlab WA Page Main Text Page