421
AUUS46 KPDT 281325
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PST FRI NOV 28 2025

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 4-10 MPH.        W 3-6 MPH.
TRANSPORT WINDS               NW 7-13 MPH.        W 4-7 MPH.
MIXING HEIGHT                 NEAR SURFACE.       3000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR SAT NOV 29        POOR.
OUTLOOK FOR SUN NOV 30        POOR.

VENTILATION INDEX (CATEGORY)  48 (POOR).          108 (POOR).
OUTLOOK FOR SAT NOV 29        64 (POOR).
OUTLOOK FOR SUN NOV 30        83 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 3-8 MPH.         N 2-5 MPH.
TRANSPORT WINDS               N 6-11 MPH.         NE 4-8 MPH.
MIXING HEIGHT                 NEAR SURFACE.       3000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR SAT NOV 29        POOR.
OUTLOOK FOR SUN NOV 30        POOR.

VENTILATION INDEX (CATEGORY)  54 (POOR).          115 (POOR).
OUTLOOK FOR SAT NOV 29        75 (POOR).
OUTLOOK FOR SUN NOV 30        41 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 2-4 MPH.         NW 5-9 MPH.
TRANSPORT WINDS               SW 6-9 MPH.         NW 11-15 MPH.
MIXING HEIGHT                 4000 FT MSL.        5500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR SAT NOV 29        GOOD.
OUTLOOK FOR SUN NOV 30        FAIR.

VENTILATION INDEX (CATEGORY)  80 (POOR).          290 (POOR).
OUTLOOK FOR SAT NOV 29        254 (POOR).
OUTLOOK FOR SUN NOV 30        179 (POOR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 W 3-7 MPH.          W 3-7 MPH.
TRANSPORT WINDS               W 5-9 MPH.          W 5-9 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2500 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR SAT NOV 29        POOR.
OUTLOOK FOR SUN NOV 30        POOR.

VENTILATION INDEX (CATEGORY)  56 (POOR).          96 (POOR).
OUTLOOK FOR SAT NOV 29        44 (POOR).
OUTLOOK FOR SUN NOV 30        107 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM       81 (POOR)
ELLENSBURG     46 (POOR)
GOLDENDALE     67 (POOR)
TRI-CITIES    126 (POOR)
WALLA WALLA    81 (POOR)
YAKIMA         70 (POOR)
BEND          153 (POOR)
PRINEVILLE     82 (POOR)
ENTERPRISE    369 (FAIR)
HERMISTON     101 (POOR)
JOHN DAY      312 (FAIR)
LA GRANDE     319 (FAIR)
MADRAS        100 (POOR)
MEACHAM        97 (POOR)
PENDLETON     110 (POOR)
REDMOND       119 (POOR)
SENECA        298 (POOR)
THE DALLES     67 (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.
$$