714
AUUS46 KPDT 041225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT THU SEP  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                 S 4-11 MPH.         NW 7-10 MPH.
TRANSPORT WINDS               SW 8-14 MPH.        NW 7-10 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR FRI SEP 5         FAIR.
OUTLOOK FOR SAT SEP 6         FAIR.

VENTILATION INDEX (CATEGORY)  71 (POOR).          312 (FAIR).
OUTLOOK FOR FRI SEP 5         196 (POOR).
OUTLOOK FOR SAT SEP 6         207 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 3-7 MPH.         E 4-7 MPH.
TRANSPORT WINDS               NW 5-9 MPH.         NE 4-7 MPH.
MIXING HEIGHT                 NEAR SURFACE.       8000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR FRI SEP 5         FAIR.
OUTLOOK FOR SAT SEP 6         FAIR.

VENTILATION INDEX (CATEGORY)  46 (POOR).          236 (POOR).
OUTLOOK FOR FRI SEP 5         241 (POOR).
OUTLOOK FOR SAT SEP 6         284 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 2-5 MPH.          N 8-10 MPH.
TRANSPORT WINDS               W 4-7 MPH.          N 8-10 MPH.
MIXING HEIGHT                 4000 FT MSL.        12000 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR FRI SEP 5         GOOD.
OUTLOOK FOR SAT SEP 6         GOOD.

VENTILATION INDEX (CATEGORY)  61 (POOR).          555 (FAIR).
OUTLOOK FOR FRI SEP 5         388 (FAIR).
OUTLOOK FOR SAT SEP 6         331 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 5-10 MPH.         NW 7-9 MPH.
TRANSPORT WINDS               S 10-14 MPH.        NW 7-9 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6500 FT MSL.
DISPERSION CATEGORY           FAIR.               FAIR.
OUTLOOK FOR FRI SEP 5         FAIR.
OUTLOOK FOR SAT SEP 6         FAIR.

VENTILATION INDEX (CATEGORY)  107 (POOR).         357 (FAIR).
OUTLOOK FOR FRI SEP 5         209 (POOR).
OUTLOOK FOR SAT SEP 6         224 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      304 (FAIR)
ELLENSBURG    338 (FAIR)
GOLDENDALE    383 (FAIR)
TRI-CITIES    189 (POOR)
WALLA WALLA   311 (FAIR)
YAKIMA        259 (POOR)
BEND          395 (FAIR)
PRINEVILLE    549 (FAIR)
ENTERPRISE    523 (FAIR)
HERMISTON     295 (POOR)
JOHN DAY      225 (POOR)
LA GRANDE     594 (FAIR)
MADRAS        530 (FAIR)
MEACHAM       336 (FAIR)
PENDLETON     401 (FAIR)
REDMOND       572 (FAIR)
SENECA        255 (POOR)
THE DALLES    244 (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.
$$