199
AUUS46 KPDT 221225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT TUE SEP 22 2026

*** AIR DISPERSION CATEGORIES:   GOOD, FAIR, POOR ***

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SW 6-16 MPH.        SW 9-17 MPH.
TRANSPORT WINDS               SW 9-16 MPH.        W 11-19 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5000 FT MSL.
DISPERSION CATEGORY           FAIR.               FAIR.
OUTLOOK FOR WED SEP 23        FAIR.
OUTLOOK FOR THU SEP 24        POOR.

VENTILATION INDEX (CATEGORY)  98 (POOR).          387 (FAIR).
OUTLOOK FOR WED SEP 23        253 (POOR).
OUTLOOK FOR THU SEP 24        108 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 W 2-9 MPH.          NW 2-6 MPH.
TRANSPORT WINDS               NW 6-12 MPH.        W 5-9 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR WED SEP 23        POOR.
OUTLOOK FOR THU SEP 24        POOR.

VENTILATION INDEX (CATEGORY)  47 (POOR).          234 (POOR).
OUTLOOK FOR WED SEP 23        157 (POOR).
OUTLOOK FOR THU SEP 24        63 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SW 0-3 MPH.         NW 7-10 MPH.
TRANSPORT WINDS               W 4-8 MPH.          NW 9-12 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR WED SEP 23        FAIR.
OUTLOOK FOR THU SEP 24        GOOD.

VENTILATION INDEX (CATEGORY)  37 (POOR).          267 (POOR).
OUTLOOK FOR WED SEP 23        158 (POOR).
OUTLOOK FOR THU SEP 24        542 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 4-13 MPH.         W 8-13 MPH.
TRANSPORT WINDS               SW 9-16 MPH.        W 12-17 MPH.
MIXING HEIGHT                 NEAR SURFACE.       4500 FT MSL.
DISPERSION CATEGORY           FAIR.               FAIR.
OUTLOOK FOR WED SEP 23        FAIR.
OUTLOOK FOR THU SEP 24        POOR.

VENTILATION INDEX (CATEGORY)  102 (POOR).         373 (FAIR).
OUTLOOK FOR WED SEP 23        226 (POOR).
OUTLOOK FOR THU SEP 24        106 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      462 (FAIR)
ELLENSBURG    574 (FAIR)
GOLDENDALE    440 (FAIR)
TRI-CITIES    325 (FAIR)
WALLA WALLA   410 (FAIR)
YAKIMA        353 (FAIR)
BEND          282 (POOR)
PRINEVILLE    306 (FAIR)
ENTERPRISE    288 (POOR)
HERMISTON     429 (FAIR)
JOHN DAY      387 (FAIR)
LA GRANDE     303 (FAIR)
MADRAS        253 (POOR)
MEACHAM       241 (POOR)
PENDLETON     449 (FAIR)
REDMOND       341 (FAIR)
SENECA        543 (FAIR)
THE DALLES    578 (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.
$$