159
AUUS46 KPDT 131225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT MON OCT 13 2025

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 N 5-15 MPH.         N 12-20 MPH.
TRANSPORT WINDS               NE 6-15 MPH.        N 12-20 MPH.
MIXING HEIGHT                 NEAR SURFACE.       4500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR TUE OCT 14        POOR.
OUTLOOK FOR WED OCT 15        FAIR.

VENTILATION INDEX (CATEGORY)  71 (POOR).          359 (FAIR).
OUTLOOK FOR TUE OCT 14        157 (POOR).
OUTLOOK FOR WED OCT 15        191 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 N 12-20 MPH.        N 16-20 MPH.
TRANSPORT WINDS               NE 14-22 MPH.       N 17-25 MPH.
MIXING HEIGHT                 2000 FT MSL.        4500 FT MSL.
DISPERSION CATEGORY           GOOD.               GOOD.
OUTLOOK FOR TUE OCT 14        FAIR.
OUTLOOK FOR WED OCT 15        POOR.

VENTILATION INDEX (CATEGORY)  252 (POOR).         485 (FAIR).
OUTLOOK FOR TUE OCT 14        379 (FAIR).
OUTLOOK FOR WED OCT 15        113 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 N 5-9 MPH.          N 7-9 MPH.
TRANSPORT WINDS               NE 5-9 MPH.         N 7-9 MPH.
MIXING HEIGHT                 4000 FT MSL.        6500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR TUE OCT 14        FAIR.
OUTLOOK FOR WED OCT 15        FAIR.

VENTILATION INDEX (CATEGORY)  69 (POOR).          162 (POOR).
OUTLOOK FOR TUE OCT 14        213 (POOR).
OUTLOOK FOR WED OCT 15        342 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NE 3-10 MPH.        N 8-15 MPH.
TRANSPORT WINDS               NE 5-10 MPH.        N 8-15 MPH.
MIXING HEIGHT                 NEAR SURFACE.       4000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR TUE OCT 14        POOR.
OUTLOOK FOR WED OCT 15        FAIR.

VENTILATION INDEX (CATEGORY)  52 (POOR).          218 (POOR).
OUTLOOK FOR TUE OCT 14        113 (POOR).
OUTLOOK FOR WED OCT 15        233 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      657 (GOOD)
ELLENSBURG    561 (FAIR)
GOLDENDALE    393 (FAIR)
TRI-CITIES    641 (GOOD)
WALLA WALLA   164 (POOR)
YAKIMA        544 (FAIR)
BEND          279 (POOR)
PRINEVILLE    407 (FAIR)
ENTERPRISE     69 (POOR)
HERMISTON     345 (FAIR)
JOHN DAY      243 (POOR)
LA GRANDE     167 (POOR)
MADRAS        510 (FAIR)
MEACHAM       101 (POOR)
PENDLETON     268 (POOR)
REDMOND       390 (FAIR)
SENECA        245 (POOR)
THE DALLES    411 (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.
$$