097
AUUS46 KPDT 041225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT SAT OCT  4 2025

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SW 5-13 MPH.        W 8-10 MPH.
TRANSPORT WINDS               SW 8-14 MPH.        W 9-12 MPH.
MIXING HEIGHT                 NEAR SURFACE.       7500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR SUN OCT 5         FAIR.
OUTLOOK FOR MON OCT 6         FAIR.

VENTILATION INDEX (CATEGORY)  84 (POOR).          510 (FAIR).
OUTLOOK FOR SUN OCT 5         215 (POOR).
OUTLOOK FOR MON OCT 6         150 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 W 4-8 MPH.          NW 7-10 MPH.
TRANSPORT WINDS               NW 6-11 MPH.        NW 9-13 MPH.
MIXING HEIGHT                 NEAR SURFACE.       8000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR SUN OCT 5         FAIR.
OUTLOOK FOR MON OCT 6         FAIR.

VENTILATION INDEX (CATEGORY)  81 (POOR).          564 (FAIR).
OUTLOOK FOR SUN OCT 5         629 (GOOD).
OUTLOOK FOR MON OCT 6         172 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 N 4-9 MPH.          NW 11-16 MPH.
TRANSPORT WINDS               W 5-9 MPH.          NW 12-15 MPH.
MIXING HEIGHT                 4000 FT MSL.        8000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR SUN OCT 5         GOOD.
OUTLOOK FOR MON OCT 6         POOR.

VENTILATION INDEX (CATEGORY)  129 (POOR).         608 (GOOD).
OUTLOOK FOR SUN OCT 5         548 (FAIR).
OUTLOOK FOR MON OCT 6         159 (POOR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SW 6-13 MPH.        W 8-12 MPH.
TRANSPORT WINDS               SW 9-15 MPH.        W 11-14 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6000 FT MSL.
DISPERSION CATEGORY           FAIR.               FAIR.
OUTLOOK FOR SUN OCT 5         FAIR.
OUTLOOK FOR MON OCT 6         FAIR.

VENTILATION INDEX (CATEGORY)  121 (POOR).         529 (FAIR).
OUTLOOK FOR SUN OCT 5         157 (POOR).
OUTLOOK FOR MON OCT 6         176 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      664 (GOOD)
ELLENSBURG    752 (GOOD)
GOLDENDALE    556 (FAIR)
TRI-CITIES    461 (FAIR)
WALLA WALLA   490 (FAIR)
YAKIMA        770 (GOOD)
BEND          365 (FAIR)
PRINEVILLE    315 (FAIR)
ENTERPRISE    664 (GOOD)
HERMISTON     493 (FAIR)
JOHN DAY      530 (FAIR)
LA GRANDE     693 (GOOD)
MADRAS        474 (FAIR)
MEACHAM       440 (FAIR)
PENDLETON     628 (GOOD)
REDMOND       346 (FAIR)
SENECA        583 (FAIR)
THE DALLES    798 (GOOD)

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.
$$