051  
FNUS76 KPDT 212235  
FWSPDT  
 
SPOT FORECAST FOR BOWMAN CREEK RX...WASHINGTON DNR  
NATIONAL WEATHER SERVICE PENDLETON OR  
335 PM PDT MON SEP 21 2026  
 
FORECAST IS BASED ON IGNITION TIME OF 1800 PDT ON SEPTEMBER 21.  
***THUNDERSTORMS IMPLY GUSTY AND ERRATIC WINDS ***  
***WINDS ARE 20 FOOT 10-MINUTE AVERAGES ***  
***CWR: CHANCE OF WETTING RAIN 0.10 OR GREATER ***  
***VENTILATION INDEX IS DERIVED FROM TRANSPORT WIND  
MULTIPLIED BY THE MIXING HEIGHT IN 100'S OF FT.  
CATEGORIES ARE A GENERALIZED INDICATOR ONLY:  
LOW (< 200), MODERATE (200-500), HIGH (500-700),  
AND VERY HIGH (> 700). ***  
 
IF YOU HAVE QUESTIONS OR CONCERNS WITH THIS FORECAST, PLEASE  
CONTACT OUR OFFICE AT (541) 276-8134.  
   
DISCUSSION
 
 
MAXIMUM HUMIDITY OVERNIGHT WILL REACH AROUND 95 PERCENT  
AS WINDS REMAIN STEADY AROUND 10 MPH. WARMING TEMPERATURES  
TUESDAY WILL DRIVE RH BACK DOWN TO AROUND 40 PERCENT IN THE  
AFTERNOON. THERE IS NO PROBABILITY FOR THUNDERSTORMS DURING  
PERIOD. BREEZY TO GUSTY CONDITIONS ARE EXPECTED TUESDAY AFTERNOON.  
 
   
TONIGHT
 
 
SKY/WEATHER.........MOSTLY CLOUDY (45-55 PERCENT) THEN BECOMING.  
CWR.................0 PERCENT.  
CHANCE OF LIGHTNING.0 PERCENT.  
MIN TEMPERATURE.....AROUND 50.  
MAX HUMIDITY........93-98 PERCENT.  
WIND (20 FT)........WEST WINDS 5 TO 10 MPH.  
RIDGETOP WIND.......WEST WINDS 7 TO 14 MPH.  
MIXING HEIGHT.......500 FT AGL IN THE EVENING AND OVERNIGHT.  
TRANSPORT WINDS.....WEST 10 TO 13 MPH.  
VENTILATION INDEX...LOW (100) DECREASING TO LOW (40) OVERNIGHT.  
 
TIME (PDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
CHC OF LTNG (%).0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............78 74 66 63 61 59 57 55 53 52 49 49  
RH..............43 52 61 64 68 71 76 81 84 87 92 93  
20 FT WIND DIR..W W W W W W W W W W W W  
20 FT WIND SPD..12 10 8 8 8 10 8 8 8 7 7 8  
20 FT WIND GUST.14 13 11 11 11 12 11 11 10 10 10 10  
   
TUESDAY
 
 
SKY/WEATHER.........MOSTLY SUNNY (40-50 PERCENT) THEN BECOMING  
MOSTLY SUNNY (35-45 PERCENT).  
CWR.................0 PERCENT.  
CHANCE OF LIGHTNING.0 PERCENT.  
MAX TEMPERATURE.....73-76.  
MIN HUMIDITY........37-42 PERCENT.  
WIND (20 FT)........WEST WINDS 10 TO 20 MPH.  
RIDGETOP WIND.......WEST WINDS 20 TO 30 MPH.  
MIXING HEIGHT.......3200 FT AGL EARLY IN THE MORNING.  
TRANSPORT WINDS.....WEST 10 TO 16 MPH INCREASING TO 18 TO 20 MPH  
LATE IN THE AFTERNOON.  
VENTILATION INDEX...LOW (80) INCREASING TO MODERATE (460) IN THE  
AFTERNOON.  
   
TUESDAY NIGHT
 
 
SKY/WEATHER.........MOSTLY CLEAR (15-25 PERCENT) THEN BECOMING  
MOSTLY CLOUDY (50-60 PERCENT).  
CWR.................0 PERCENT.  
CHANCE OF LIGHTNING.0 PERCENT.  
MIN TEMPERATURE.....44-47.  
MAX HUMIDITY........83-88 PERCENT.  
WIND (20 FT)........WEST WINDS 5 TO 15 MPH WITH GUSTS TO AROUND 20  
MPH DECREASING TO 5 TO 7 MPH LATE IN THE  
EVENING.  
RIDGETOP WIND.......WEST WINDS 8 TO 18 MPH WITH GUSTS TO AROUND 23  
MPH DECREASING TO 5 TO 7 MPH LATE IN THE  
EVENING.  
MIXING HEIGHT.......500 FT AGL IN THE EVENING.  
TRANSPORT WINDS.....WEST 12 TO 18 MPH SHIFTING TO THE NORTHWEST 6  
TO 8 MPH LATE IN THE EVENING.  
VENTILATION INDEX...LOW (180) DECREASING TO LOW (30) OVERNIGHT.  
   
WEDNESDAY
 
 
SKY/WEATHER.........MOSTLY SUNNY (35-45 PERCENT).  
CWR.................0 PERCENT.  
CHANCE OF LIGHTNING.0 PERCENT.  
MAX TEMPERATURE.....74-77.  
MIN HUMIDITY........28-33 PERCENT.  
WIND (20 FT)........WEST WINDS 4 TO 8 MPH INCREASING TO 5 TO 9 MPH  
LATE IN THE AFTERNOON.  
RIDGETOP WIND.......WEST WINDS 6 TO 9 MPH INCREASING TO 9 TO 10 MPH  
LATE IN THE AFTERNOON.  
MIXING HEIGHT.......4500 FT AGL LATE IN THE MORNING.  
TRANSPORT WINDS.....WEST 5 TO 8 MPH INCREASING TO 9 TO 10 MPH LATE  
IN THE AFTERNOON.  
VENTILATION INDEX...LOW (30) INCREASING TO MODERATE (250) IN THE  
AFTERNOON.  
 

 
FORECASTER...RUSSELL  
REQUESTED BY...ADAM LIEBERG  
TYPE OF REQUEST...PRESCRIBED  
.TAG 2622141.2/PDT  
.DELDT 09/21/26  
.FORMATTERVERSION 2.0.0  
.EMAIL ALIEBERG@COLUMBIALANDTRUST.ORG  
 
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