182
AUUS46 KPDT 311225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT MON AUG 31 2026

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 E 1-5 MPH.          N 6-11 MPH.
TRANSPORT WINDS               E 3-6 MPH.          NE 7-12 MPH.
MIXING HEIGHT                 NEAR SURFACE.       4500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR TUE SEP 1         FAIR.
OUTLOOK FOR WED SEP 2         GOOD.

VENTILATION INDEX (CATEGORY)  31 (POOR).          239 (POOR).
OUTLOOK FOR TUE SEP 1         304 (FAIR).
OUTLOOK FOR WED SEP 2         671 (GOOD).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 0-3 MPH.         E 3-7 MPH.
TRANSPORT WINDS               NW 3-6 MPH.         E 4-7 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5500 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR TUE SEP 1         FAIR.
OUTLOOK FOR WED SEP 2         GOOD.

VENTILATION INDEX (CATEGORY)  29 (POOR).          206 (POOR).
OUTLOOK FOR TUE SEP 1         378 (FAIR).
OUTLOOK FOR WED SEP 2         911 (GOOD).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SW 3-8 MPH.         S 7-12 MPH.
TRANSPORT WINDS               SE 4-8 MPH.         S 11-14 MPH.
MIXING HEIGHT                 NEAR SURFACE.       10000 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR TUE SEP 1         GOOD.
OUTLOOK FOR WED SEP 2         FAIR.

VENTILATION INDEX (CATEGORY)  42 (POOR).          633 (GOOD).
OUTLOOK FOR TUE SEP 1         712 (GOOD).
OUTLOOK FOR WED SEP 2         384 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 4-9 MPH.         N 6-11 MPH.
TRANSPORT WINDS               SE 5-10 MPH.        N 7-12 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR TUE SEP 1         FAIR.
OUTLOOK FOR WED SEP 2         GOOD.

VENTILATION INDEX (CATEGORY)  42 (POOR).          208 (POOR).
OUTLOOK FOR TUE SEP 1         241 (POOR).
OUTLOOK FOR WED SEP 2         554 (FAIR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      397 (FAIR)
ELLENSBURG    334 (FAIR)
GOLDENDALE    341 (FAIR)
TRI-CITIES    208 (POOR)
WALLA WALLA   182 (POOR)
YAKIMA        219 (POOR)
BEND          409 (FAIR)
PRINEVILLE    720 (GOOD)
ENTERPRISE    469 (FAIR)
HERMISTON     269 (POOR)
JOHN DAY     1050 (GOOD)
LA GRANDE     640 (GOOD)
MADRAS        245 (POOR)
MEACHAM       487 (FAIR)
PENDLETON     281 (POOR)
REDMOND       482 (FAIR)
SENECA       1050 (GOOD)
THE DALLES    370 (FAIR)

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.
$$