538
AUUS46 KPDT 051225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT SAT SEP  5 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 2-6 MPH.          N 3-6 MPH.
TRANSPORT WINDS               S 4-8 MPH.          N 3-6 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5500 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR SUN SEP 6         FAIR.
OUTLOOK FOR MON SEP 7         GOOD.

VENTILATION INDEX (CATEGORY)  35 (POOR).          166 (POOR).
OUTLOOK FOR SUN SEP 6         227 (POOR).
OUTLOOK FOR MON SEP 7         685 (GOOD).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 1-5 MPH.         E 3-6 MPH.
TRANSPORT WINDS               NW 3-6 MPH.         SE 5-6 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6500 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR SUN SEP 6         POOR.
OUTLOOK FOR MON SEP 7         FAIR.

VENTILATION INDEX (CATEGORY)  33 (POOR).          220 (POOR).
OUTLOOK FOR SUN SEP 6         215 (POOR).
OUTLOOK FOR MON SEP 7         505 (FAIR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 E 0-1 MPH.          W 2-5 MPH.
TRANSPORT WINDS               N 2-4 MPH.          SW 8-11 MPH.
MIXING HEIGHT                 NEAR SURFACE.       7500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR SUN SEP 6         FAIR.
OUTLOOK FOR MON SEP 7         GOOD.

VENTILATION INDEX (CATEGORY)  26 (POOR).          284 (POOR).
OUTLOOK FOR SUN SEP 6         297 (POOR).
OUTLOOK FOR MON SEP 7         489 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 2-6 MPH.          N 2-5 MPH.
TRANSPORT WINDS               S 4-7 MPH.          NE 4-8 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR SUN SEP 6         FAIR.
OUTLOOK FOR MON SEP 7         FAIR.

VENTILATION INDEX (CATEGORY)  33 (POOR).          149 (POOR).
OUTLOOK FOR SUN SEP 6         261 (POOR).
OUTLOOK FOR MON SEP 7         626 (GOOD).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      366 (FAIR)
ELLENSBURG    335 (FAIR)
GOLDENDALE    214 (POOR)
TRI-CITIES    187 (POOR)
WALLA WALLA   131 (POOR)
YAKIMA        272 (POOR)
BEND          333 (FAIR)
PRINEVILLE    312 (FAIR)
ENTERPRISE    416 (FAIR)
HERMISTON     145 (POOR)
JOHN DAY      445 (FAIR)
LA GRANDE     195 (POOR)
MADRAS        194 (POOR)
MEACHAM       132 (POOR)
PENDLETON     143 (POOR)
REDMOND       293 (POOR)
SENECA        745 (GOOD)
THE DALLES    161 (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.
$$