492
AUUS46 KPDT 051225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT SUN OCT  5 2025

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 3-10 MPH.        N 6-10 MPH.
TRANSPORT WINDS               NW 6-12 MPH.        N 9-13 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR MON OCT 6         FAIR.
OUTLOOK FOR TUE OCT 7         FAIR.

VENTILATION INDEX (CATEGORY)  61 (POOR).          341 (FAIR).
OUTLOOK FOR MON OCT 6         129 (POOR).
OUTLOOK FOR TUE OCT 7         113 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 5-11 MPH.        NE 8-11 MPH.
TRANSPORT WINDS               NW 6-14 MPH.        NE 10-14 MPH.
MIXING HEIGHT                 NEAR SURFACE.       7000 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR MON OCT 6         FAIR.
OUTLOOK FOR TUE OCT 7         FAIR.

VENTILATION INDEX (CATEGORY)  115 (POOR).         595 (FAIR).
OUTLOOK FOR MON OCT 6         158 (POOR).
OUTLOOK FOR TUE OCT 7         128 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 2-6 MPH.         N 10-13 MPH.
TRANSPORT WINDS               NW 4-8 MPH.         N 11-13 MPH.
MIXING HEIGHT                 4000 FT MSL.        9500 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR MON OCT 6         POOR.
OUTLOOK FOR TUE OCT 7         GOOD.

VENTILATION INDEX (CATEGORY)  87 (POOR).          635 (GOOD).
OUTLOOK FOR MON OCT 6         134 (POOR).
OUTLOOK FOR TUE OCT 7         724 (GOOD).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SW 2-5 MPH.         N 6-8 MPH.
TRANSPORT WINDS               SW 4-7 MPH.         N 7-9 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR MON OCT 6         FAIR.
OUTLOOK FOR TUE OCT 7         FAIR.

VENTILATION INDEX (CATEGORY)  55 (POOR).          270 (POOR).
OUTLOOK FOR MON OCT 6         152 (POOR).
OUTLOOK FOR TUE OCT 7         322 (FAIR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      426 (FAIR)
ELLENSBURG    442 (FAIR)
GOLDENDALE    635 (GOOD)
TRI-CITIES    508 (FAIR)
WALLA WALLA   193 (POOR)
YAKIMA        600 (FAIR)
BEND          466 (FAIR)
PRINEVILLE    450 (FAIR)
ENTERPRISE    415 (FAIR)
HERMISTON     382 (FAIR)
JOHN DAY      582 (FAIR)
LA GRANDE     596 (FAIR)
MADRAS        602 (GOOD)
MEACHAM       317 (FAIR)
PENDLETON     348 (FAIR)
REDMOND       482 (FAIR)
SENECA        523 (FAIR)
THE DALLES    587 (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.
$$