665
AUUS46 KPDT 301225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT SUN AUG 30 2026

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 5-13 MPH.         W 7-10 MPH.
TRANSPORT WINDS               SW 8-15 MPH.        W 8-11 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR MON AUG 31        FAIR.
OUTLOOK FOR TUE SEP 1         FAIR.

VENTILATION INDEX (CATEGORY)  128 (POOR).         416 (FAIR).
OUTLOOK FOR MON AUG 31        249 (POOR).
OUTLOOK FOR TUE SEP 1         273 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 W 0-5 MPH.          SE 2-6 MPH.
TRANSPORT WINDS               W 3-7 MPH.          W 4-7 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5500 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR MON AUG 31        FAIR.
OUTLOOK FOR TUE SEP 1         FAIR.

VENTILATION INDEX (CATEGORY)  33 (POOR).          184 (POOR).
OUTLOOK FOR MON AUG 31        221 (POOR).
OUTLOOK FOR TUE SEP 1         264 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 1-3 MPH.         W 1-4 MPH.
TRANSPORT WINDS               SW 3-6 MPH.         W 7-9 MPH.
MIXING HEIGHT                 NEAR SURFACE.       8500 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR MON AUG 31        GOOD.
OUTLOOK FOR TUE SEP 1         GOOD.

VENTILATION INDEX (CATEGORY)  41 (POOR).          305 (FAIR).
OUTLOOK FOR MON AUG 31        557 (FAIR).
OUTLOOK FOR TUE SEP 1         564 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 5-13 MPH.         W 5-9 MPH.
TRANSPORT WINDS               S 8-14 MPH.         W 7-12 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR MON AUG 31        FAIR.
OUTLOOK FOR TUE SEP 1         FAIR.

VENTILATION INDEX (CATEGORY)  136 (POOR).         381 (FAIR).
OUTLOOK FOR MON AUG 31        199 (POOR).
OUTLOOK FOR TUE SEP 1         256 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      367 (FAIR)
ELLENSBURG    536 (FAIR)
GOLDENDALE    238 (POOR)
TRI-CITIES    407 (FAIR)
WALLA WALLA   443 (FAIR)
YAKIMA        169 (POOR)
BEND          137 (POOR)
PRINEVILLE    146 (POOR)
ENTERPRISE    381 (FAIR)
HERMISTON     420 (FAIR)
JOHN DAY      327 (FAIR)
LA GRANDE     319 (FAIR)
MADRAS        137 (POOR)
MEACHAM       318 (FAIR)
PENDLETON     339 (FAIR)
REDMOND        93 (POOR)
SENECA        335 (FAIR)
THE DALLES    305 (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.
$$