677
AUUS46 KPDT 221325
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PST SAT NOV 22 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 2-6 MPH.         NW 2-4 MPH.
TRANSPORT WINDS               S 3-7 MPH.          SW 2-5 MPH.
MIXING HEIGHT                 NEAR SURFACE.       NEAR SURFACE.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR SUN NOV 23        FAIR.
OUTLOOK FOR MON NOV 24        FAIR.

VENTILATION INDEX (CATEGORY)  26 (POOR).          30 (POOR).
OUTLOOK FOR SUN NOV 23        92 (POOR).
OUTLOOK FOR MON NOV 24        504 (FAIR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 1-3 MPH.         SE 2-3 MPH.
TRANSPORT WINDS               NW 1-3 MPH.         S 2-5 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR SUN NOV 23        FAIR.
OUTLOOK FOR MON NOV 24        FAIR.

VENTILATION INDEX (CATEGORY)  25 (POOR).          33 (POOR).
OUTLOOK FOR SUN NOV 23        114 (POOR).
OUTLOOK FOR MON NOV 24        354 (FAIR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 5-9 MPH.          S 12-16 MPH.
TRANSPORT WINDS               S 9-12 MPH.         S 19-21 MPH.
MIXING HEIGHT                 4000 FT MSL.        5000 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR SUN NOV 23        GOOD.
OUTLOOK FOR MON NOV 24        GOOD.

VENTILATION INDEX (CATEGORY)  115 (POOR).         389 (FAIR).
OUTLOOK FOR SUN NOV 23        405 (FAIR).
OUTLOOK FOR MON NOV 24        634 (GOOD).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 4-8 MPH.         W 3-6 MPH.
TRANSPORT WINDS               S 6-11 MPH.         S 4-9 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2500 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR SUN NOV 23        FAIR.
OUTLOOK FOR MON NOV 24        GOOD.

VENTILATION INDEX (CATEGORY)  50 (POOR).          67 (POOR).
OUTLOOK FOR SUN NOV 23        126 (POOR).
OUTLOOK FOR MON NOV 24        606 (GOOD).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM       99 (POOR)
ELLENSBURG     38 (POOR)
GOLDENDALE     50 (POOR)
TRI-CITIES     25 (POOR)
WALLA WALLA    41 (POOR)
YAKIMA         26 (POOR)
BEND          170 (POOR)
PRINEVILLE    135 (POOR)
ENTERPRISE     84 (POOR)
HERMISTON      25 (POOR)
JOHN DAY      216 (POOR)
LA GRANDE     357 (FAIR)
MADRAS        121 (POOR)
MEACHAM       113 (POOR)
PENDLETON      37 (POOR)
REDMOND       130 (POOR)
SENECA        214 (POOR)
THE DALLES     42 (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.
$$