602
AUUS46 KPDT 251325
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PST TUE NOV 25 2025

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 3-7 MPH.         NW 3-5 MPH.
TRANSPORT WINDS               SE 3-6 MPH.         SW 5-9 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR WED NOV 26        POOR.
OUTLOOK FOR THU NOV 27        POOR.

VENTILATION INDEX (CATEGORY)  27 (POOR).          28 (POOR).
OUTLOOK FOR WED NOV 26        46 (POOR).
OUTLOOK FOR THU NOV 27        46 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 N 1-3 MPH.          E 2-5 MPH.
TRANSPORT WINDS               N 2-4 MPH.          SE 4-8 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2500 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR WED NOV 26        POOR.
OUTLOOK FOR THU NOV 27        POOR.

VENTILATION INDEX (CATEGORY)  25 (POOR).          37 (POOR).
OUTLOOK FOR WED NOV 26        39 (POOR).
OUTLOOK FOR THU NOV 27        69 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 2-4 MPH.         S 9-11 MPH.
TRANSPORT WINDS               S 5-9 MPH.          S 15-17 MPH.
MIXING HEIGHT                 4000 FT MSL.        5500 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR WED NOV 26        POOR.
OUTLOOK FOR THU NOV 27        GOOD.

VENTILATION INDEX (CATEGORY)  98 (POOR).          355 (FAIR).
OUTLOOK FOR WED NOV 26        242 (POOR).
OUTLOOK FOR THU NOV 27        191 (POOR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 4-8 MPH.         SW 4-6 MPH.
TRANSPORT WINDS               S 6-11 MPH.         SW 8-11 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2500 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR WED NOV 26        POOR.
OUTLOOK FOR THU NOV 27        POOR.

VENTILATION INDEX (CATEGORY)  48 (POOR).          76 (POOR).
OUTLOOK FOR WED NOV 26        58 (POOR).
OUTLOOK FOR THU NOV 27        80 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      186 (POOR)
ELLENSBURG     62 (POOR)
GOLDENDALE     49 (POOR)
TRI-CITIES     25 (POOR)
WALLA WALLA    35 (POOR)
YAKIMA         41 (POOR)
BEND          159 (POOR)
PRINEVILLE     96 (POOR)
ENTERPRISE     76 (POOR)
HERMISTON      25 (POOR)
JOHN DAY      213 (POOR)
LA GRANDE     305 (FAIR)
MADRAS         88 (POOR)
MEACHAM       100 (POOR)
PENDLETON      32 (POOR)
REDMOND       109 (POOR)
SENECA        230 (POOR)
THE DALLES     53 (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.
$$