893
AUUS46 KPDT 301225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT WED JUL 30 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 3-7 MPH.          N 6-10 MPH.
TRANSPORT WINDS               SW 5-9 MPH.         N 7-10 MPH.
MIXING HEIGHT                 NEAR SURFACE.       10500 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR THU JUL 31        FAIR.
OUTLOOK FOR FRI AUG 1         FAIR.

VENTILATION INDEX (CATEGORY)  54 (POOR).          468 (FAIR).
OUTLOOK FOR THU JUL 31        514 (FAIR).
OUTLOOK FOR FRI AUG 1         687 (GOOD).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 3-7 MPH.         E 6-9 MPH.
TRANSPORT WINDS               NW 6-11 MPH.        NE 5-9 MPH.
MIXING HEIGHT                 NEAR SURFACE.       13500 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR THU JUL 31        GOOD.
OUTLOOK FOR FRI AUG 1         FAIR.

VENTILATION INDEX (CATEGORY)  82 (POOR).          579 (FAIR).
OUTLOOK FOR THU JUL 31        447 (FAIR).
OUTLOOK FOR FRI AUG 1         334 (FAIR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 2-5 MPH.         N 7-9 MPH.
TRANSPORT WINDS               NW 4-7 MPH.         N 8-10 MPH.
MIXING HEIGHT                 4000 FT MSL.        15000 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR THU JUL 31        GOOD.
OUTLOOK FOR FRI AUG 1         GOOD.

VENTILATION INDEX (CATEGORY)  82 (POOR).          895 (GOOD).
OUTLOOK FOR THU JUL 31        313 (FAIR).
OUTLOOK FOR FRI AUG 1         467 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 3-7 MPH.          N 7-9 MPH.
TRANSPORT WINDS               S 6-10 MPH.         N 8-10 MPH.
MIXING HEIGHT                 NEAR SURFACE.       10000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR THU JUL 31        FAIR.
OUTLOOK FOR FRI AUG 1         GOOD.

VENTILATION INDEX (CATEGORY)  57 (POOR).          517 (FAIR).
OUTLOOK FOR THU JUL 31        455 (FAIR).
OUTLOOK FOR FRI AUG 1         707 (GOOD).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      337 (FAIR)
ELLENSBURG    553 (FAIR)
GOLDENDALE    369 (FAIR)
TRI-CITIES    427 (FAIR)
WALLA WALLA   374 (FAIR)
YAKIMA        667 (GOOD)
BEND          637 (GOOD)
PRINEVILLE    688 (GOOD)
ENTERPRISE    657 (GOOD)
HERMISTON     439 (FAIR)
JOHN DAY      615 (GOOD)
LA GRANDE     904 (GOOD)
MADRAS        695 (GOOD)
MEACHAM       629 (GOOD)
PENDLETON     518 (FAIR)
REDMOND       704 (GOOD)
SENECA        594 (FAIR)
THE DALLES    430 (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.
$$