898  
AUUS46 KPDT 171121  
DDOPDT  
 
DAILY DISPERSION OUTLOOK  
NATIONAL WEATHER SERVICE PENDLETON OR  
421 AM PDT SUN OCT 17 2021  
 
*** AIR DISPERSION CATEGORIES: GOOD, FAIR, POOR ***  
 
FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO  
 
7:00 AM AFTERNOON  
SURFACE WINDS S 2-8 MPH. NW 7-10 MPH.  
TRANSPORT WINDS S 2-8 MPH. NW 2-8 MPH.  
MIXING HEIGHT NEAR SURFACE. 3500 FT MSL.  
DISPERSION CATEGORY POOR. POOR.  
OUTLOOK FOR MON OCT 18 FAIR.  
 
VENTILATION INDEX (CATEGORY) 40 (POOR). 56 (POOR).  
OUTLOOK FOR MON OCT 18 415 (FAIR).  
 
FOR THE UPPER YAKIMA VALLEY INCLUDING YAKIMA...UNION GAP...  
SELAH...AND NACHES AREA  
 
7:00 AM AFTERNOON  
SURFACE WINDS W 3-6 MPH. W 2-8 MPH.  
TRANSPORT WINDS W 3-6 MPH. W 5-10 MPH.  
MIXING HEIGHT NEAR SURFACE. 4000 FT MSL.  
DISPERSION CATEGORY POOR. FAIR.  
OUTLOOK FOR MON OCT 18 FAIR.  
 
VENTILATION INDEX (CATEGORY) 27 (POOR). 109 (POOR).  
OUTLOOK FOR MON OCT 18 299 (POOR).  
 
FOR THE GRANDE RONDE RIVER VALLEY  
 
7:00 AM AFTERNOON  
SURFACE WINDS S 15-20 MPH. S 12-16 MPH.  
TRANSPORT WINDS S 20-25 MPH. S 20-25 MPH.  
MIXING HEIGHT 4000 FT MSL. 7000 FT MSL.  
DISPERSION CATEGORY FAIR. GOOD.  
OUTLOOK FOR MON OCT 18 FAIR.  
 
VENTILATION INDEX (CATEGORY) 408 (FAIR). 689 (GOOD).  
OUTLOOK FOR MON OCT 18 285 (POOR).  
 
SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES  
CLE ELUM 177 (POOR)  
ELLENSBURG 185 (POOR)  
GOLDENDALE 171 (POOR)  
TRI-CITIES 40 (POOR)  
WALLA WALLA 60 (POOR)  
YAKIMA 202 (POOR)  
BEND 1050 (GOOD)  
PRINEVILLE 1050 (GOOD)  
ENTERPRISE 922 (GOOD)  
HERMISTON 52 (POOR)  
JOHN DAY 1050 (GOOD)  
LA GRANDE 676 (GOOD)  
MADRAS 305 (FAIR)  
MEACHAM 1050 (GOOD)  
PENDLETON 87 (POOR)  
REDMOND 1050 (GOOD)  
SENECA 1050 (GOOD)  
THE DALLES 148 (POOR)  
 
METEOROLOGICAL INFORMATION PROVIDED IN THIS PRODUCT REPRESENTS ONLY  
SOME OF THE FACTORS USED IN BURN DECISIONS. BURN DECISIONS ARE  
OUTSIDE THE PURVIEW OF THE NATIONAL WEATHER SERVICE.  
 
THE VENTILATION INDEX IS A TOOL TO ASSIST SMOKE MANAGEMENT  
AGENCIES IN DETERMINING BURN OR NO BURN DECISIONS. A VENTILATION  
INDEX GRAPHIC IS ON THE PENDLETON WEBSITE AT THE FOLLOWING ADDRESS:  
HTTP://WWW.WRH.NOAA.GOV/PDT/GFORECAST/GINDEX.PHP?FCST=MIXHGT,VENTCAT,TRANSWIND,VENTINDX&VT=0,72  
 
IF YOU WOULD LIKE TO KNOW MORE ABOUT THIS PRODUCT...CONTACT THE  
NATIONAL WEATHER SERVICE IN PENDLETON.  
 

 
 
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