862
AUUS46 KPDT 231225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT SAT AUG 23 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.         N 8-11 MPH.
TRANSPORT WINDS               SW 4-8 MPH.         NE 8-11 MPH.
MIXING HEIGHT                 NEAR SURFACE.       4500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR SUN AUG 24        FAIR.
OUTLOOK FOR MON AUG 25        FAIR.

VENTILATION INDEX (CATEGORY)  32 (POOR).          210 (POOR).
OUTLOOK FOR SUN AUG 24        184 (POOR).
OUTLOOK FOR MON AUG 25        218 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 4-8 MPH.         NE 6-10 MPH.
TRANSPORT WINDS               NW 6-11 MPH.        NE 6-10 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR SUN AUG 24        FAIR.
OUTLOOK FOR MON AUG 25        POOR.

VENTILATION INDEX (CATEGORY)  77 (POOR).          341 (FAIR).
OUTLOOK FOR SUN AUG 24        311 (FAIR).
OUTLOOK FOR MON AUG 25        208 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 N 2-4 MPH.          N 3-4 MPH.
TRANSPORT WINDS               N 3-6 MPH.          N 6-8 MPH.
MIXING HEIGHT                 4000 FT MSL.        10500 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR SUN AUG 24        GOOD.
OUTLOOK FOR MON AUG 25        GOOD.

VENTILATION INDEX (CATEGORY)  42 (POOR).          298 (POOR).
OUTLOOK FOR SUN AUG 24        323 (FAIR).
OUTLOOK FOR MON AUG 25        430 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 4-8 MPH.         N 7-9 MPH.
TRANSPORT WINDS               S 6-8 MPH.          N 8-10 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR SUN AUG 24        FAIR.
OUTLOOK FOR MON AUG 25        FAIR.

VENTILATION INDEX (CATEGORY)  30 (POOR).          231 (POOR).
OUTLOOK FOR SUN AUG 24        176 (POOR).
OUTLOOK FOR MON AUG 25        296 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      434 (FAIR)
ELLENSBURG    403 (FAIR)
GOLDENDALE    452 (FAIR)
TRI-CITIES    211 (POOR)
WALLA WALLA   172 (POOR)
YAKIMA        349 (FAIR)
BEND          135 (POOR)
PRINEVILLE    296 (POOR)
ENTERPRISE    452 (FAIR)
HERMISTON     229 (POOR)
JOHN DAY      660 (GOOD)
LA GRANDE     305 (FAIR)
MADRAS        278 (POOR)
MEACHAM       217 (POOR)
PENDLETON     271 (POOR)
REDMOND       143 (POOR)
SENECA        843 (GOOD)
THE DALLES    453 (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.
$$