135
AUUS46 KPDT 101225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT THU SEP 10 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 4-12 MPH.         W 11-23 MPH.
TRANSPORT WINDS               SW 7-13 MPH.        W 14-24 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6500 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR FRI SEP 11        FAIR.
OUTLOOK FOR SAT SEP 12        FAIR.

VENTILATION INDEX (CATEGORY)  83 (POOR).          656 (GOOD).
OUTLOOK FOR FRI SEP 11        311 (FAIR).
OUTLOOK FOR SAT SEP 12        208 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 W 0-6 MPH.          W 7-14 MPH.
TRANSPORT WINDS               NW 4-8 MPH.         W 12-16 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR FRI SEP 11        POOR.
OUTLOOK FOR SAT SEP 12        FAIR.

VENTILATION INDEX (CATEGORY)  34 (POOR).          461 (FAIR).
OUTLOOK FOR FRI SEP 11        183 (POOR).
OUTLOOK FOR SAT SEP 12        270 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 5-12 MPH.         NW 7-13 MPH.
TRANSPORT WINDS               S 8-15 MPH.         W 16-19 MPH.
MIXING HEIGHT                 NEAR SURFACE.       9000 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR FRI SEP 11        FAIR.
OUTLOOK FOR SAT SEP 12        FAIR.

VENTILATION INDEX (CATEGORY)  59 (POOR).          764 (GOOD).
OUTLOOK FOR FRI SEP 11        316 (FAIR).
OUTLOOK FOR SAT SEP 12        146 (POOR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 6-12 MPH.         W 14-20 MPH.
TRANSPORT WINDS               S 9-15 MPH.         W 18-20 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6500 FT MSL.
DISPERSION CATEGORY           FAIR.               GOOD.
OUTLOOK FOR FRI SEP 11        FAIR.
OUTLOOK FOR SAT SEP 12        FAIR.

VENTILATION INDEX (CATEGORY)  111 (POOR).         771 (GOOD).
OUTLOOK FOR FRI SEP 11        359 (FAIR).
OUTLOOK FOR SAT SEP 12        165 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      536 (FAIR)
ELLENSBURG    644 (GOOD)
GOLDENDALE    609 (GOOD)
TRI-CITIES    442 (FAIR)
WALLA WALLA   709 (GOOD)
YAKIMA        485 (FAIR)
BEND          571 (FAIR)
PRINEVILLE    617 (GOOD)
ENTERPRISE    850 (GOOD)
HERMISTON     688 (GOOD)
JOHN DAY      770 (GOOD)
LA GRANDE     853 (GOOD)
MADRAS        435 (FAIR)
MEACHAM       721 (GOOD)
PENDLETON     840 (GOOD)
REDMOND       637 (GOOD)
SENECA        907 (GOOD)
THE DALLES    652 (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.
$$