602
AUUS46 KPDT 151225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT MON SEP 15 2025

*** AIR DISPERSION CATEGORIES:   GOOD, FAIR, POOR ***

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 6-15 MPH.         NW 5-6 MPH.
TRANSPORT WINDS               SW 9-16 MPH.        E 5-6 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5500 FT MSL.
DISPERSION CATEGORY           FAIR.               POOR.
OUTLOOK FOR TUE SEP 16        POOR.
OUTLOOK FOR WED SEP 17        POOR.

VENTILATION INDEX (CATEGORY)  96 (POOR).          124 (POOR).
OUTLOOK FOR TUE SEP 16        115 (POOR).
OUTLOOK FOR WED SEP 17        86 (POOR).

FOR THE UPPER YAKIMA VALLEY INCLUDING YAKIMA...UNION GAP...
SELAH...AND NACHES AREA

                              7:00 AM             AFTERNOON
SURFACE WINDS                 W 3-7 MPH.          SE 3-7 MPH.
TRANSPORT WINDS               W 4-8 MPH.          E 5-7 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR TUE SEP 16        FAIR.
OUTLOOK FOR WED SEP 17        POOR.

VENTILATION INDEX (CATEGORY)  54 (POOR).          130 (POOR).
OUTLOOK FOR TUE SEP 16        248 (POOR).
OUTLOOK FOR WED SEP 17        116 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 1-3 MPH.         N 3-5 MPH.
TRANSPORT WINDS               W 3-6 MPH.          N 4-5 MPH.
MIXING HEIGHT                 4000 FT MSL.        8000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR TUE SEP 16        FAIR.
OUTLOOK FOR WED SEP 17        GOOD.

VENTILATION INDEX (CATEGORY)  60 (POOR).          162 (POOR).
OUTLOOK FOR TUE SEP 16        326 (FAIR).
OUTLOOK FOR WED SEP 17        349 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 5-15 MPH.         NW 5-7 MPH.
TRANSPORT WINDS               SW 9-17 MPH.        N 5-7 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5000 FT MSL.
DISPERSION CATEGORY           FAIR.               POOR.
OUTLOOK FOR TUE SEP 16        FAIR.
OUTLOOK FOR WED SEP 17        POOR.

VENTILATION INDEX (CATEGORY)  112 (POOR).         98 (POOR).
OUTLOOK FOR TUE SEP 16        167 (POOR).
OUTLOOK FOR WED SEP 17        109 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      217 (POOR)
ELLENSBURG    222 (POOR)
GOLDENDALE    165 (POOR)
TRI-CITIES    151 (POOR)
WALLA WALLA    65 (POOR)
YAKIMA        161 (POOR)
BEND          136 (POOR)
PRINEVILLE    117 (POOR)
ENTERPRISE    172 (POOR)
HERMISTON      59 (POOR)
JOHN DAY      142 (POOR)
LA GRANDE     168 (POOR)
MADRAS        118 (POOR)
MEACHAM        93 (POOR)
PENDLETON      93 (POOR)
REDMOND       132 (POOR)
SENECA        199 (POOR)
THE DALLES    117 (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:
HTTPS://WWW.WEATHER.GOV/PDT/DSSBRIEFING

IF YOU WOULD LIKE TO KNOW MORE ABOUT THIS PRODUCT...CONTACT THE
NATIONAL WEATHER SERVICE IN PENDLETON.
$$