083
AUUS46 KPDT 261225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT WED AUG 26 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 11-16 MPH.
TRANSPORT WINDS               SW 7-13 MPH.        W 14-18 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR THU AUG 27        FAIR.
OUTLOOK FOR FRI AUG 28        FAIR.

VENTILATION INDEX (CATEGORY)  85 (POOR).          525 (FAIR).
OUTLOOK FOR THU AUG 27        583 (FAIR).
OUTLOOK FOR FRI AUG 28        355 (FAIR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 W 0-5 MPH.          SW 7-17 MPH.
TRANSPORT WINDS               W 4-8 MPH.          SW 11-18 MPH.
MIXING HEIGHT                 NEAR SURFACE.       8500 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR THU AUG 27        GOOD.
OUTLOOK FOR FRI AUG 28        FAIR.

VENTILATION INDEX (CATEGORY)  33 (POOR).          585 (FAIR).
OUTLOOK FOR THU AUG 27        772 (GOOD).
OUTLOOK FOR FRI AUG 28        203 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 1-3 MPH.          SW 8-14 MPH.
TRANSPORT WINDS               S 4-5 MPH.          SW 17-21 MPH.
MIXING HEIGHT                 NEAR SURFACE.       13000 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR THU AUG 27        GOOD.
OUTLOOK FOR FRI AUG 28        FAIR.

VENTILATION INDEX (CATEGORY)  35 (POOR).          1048 (GOOD).
OUTLOOK FOR THU AUG 27        443 (FAIR).
OUTLOOK FOR FRI AUG 28        257 (POOR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 3-8 MPH.          W 8-11 MPH.
TRANSPORT WINDS               S 6-11 MPH.         W 10-16 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR THU AUG 27        FAIR.
OUTLOOK FOR FRI AUG 28        FAIR.

VENTILATION INDEX (CATEGORY)  72 (POOR).          432 (FAIR).
OUTLOOK FOR THU AUG 27        417 (FAIR).
OUTLOOK FOR FRI AUG 28        304 (FAIR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      323 (FAIR)
ELLENSBURG    454 (FAIR)
GOLDENDALE    606 (GOOD)
TRI-CITIES    570 (FAIR)
WALLA WALLA   435 (FAIR)
YAKIMA        638 (GOOD)
BEND         1050 (GOOD)
PRINEVILLE    864 (GOOD)
ENTERPRISE   1050 (GOOD)
HERMISTON     609 (GOOD)
JOHN DAY     1050 (GOOD)
LA GRANDE    1050 (GOOD)
MADRAS        572 (FAIR)
MEACHAM       504 (FAIR)
PENDLETON     461 (FAIR)
REDMOND       786 (GOOD)
SENECA       1050 (GOOD)
THE DALLES    476 (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.
$$