909
AUUS46 KPDT 151225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT TUE SEP 15 2026

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 0-5 MPH.          N 4-8 MPH.
TRANSPORT WINDS               S 3-6 MPH.          N 6-8 MPH.
MIXING HEIGHT                 NEAR SURFACE.       4500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR WED SEP 16        FAIR.
OUTLOOK FOR THU SEP 17        FAIR.

VENTILATION INDEX (CATEGORY)  26 (POOR).          131 (POOR).
OUTLOOK FOR WED SEP 16        313 (FAIR).
OUTLOOK FOR THU SEP 17        127 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 0-3 MPH.         NE 3-7 MPH.
TRANSPORT WINDS               NW 3-6 MPH.         NE 5-7 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR WED SEP 16        FAIR.
OUTLOOK FOR THU SEP 17        POOR.

VENTILATION INDEX (CATEGORY)  26 (POOR).          131 (POOR).
OUTLOOK FOR WED SEP 16        415 (FAIR).
OUTLOOK FOR THU SEP 17        150 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 1-4 MPH.          NW 2-5 MPH.
TRANSPORT WINDS               S 4-5 MPH.          SW 4-8 MPH.
MIXING HEIGHT                 NEAR SURFACE.       7500 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR WED SEP 16        FAIR.
OUTLOOK FOR THU SEP 17        FAIR.

VENTILATION INDEX (CATEGORY)  30 (POOR).          235 (POOR).
OUTLOOK FOR WED SEP 16        496 (FAIR).
OUTLOOK FOR THU SEP 17        191 (POOR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 2-6 MPH.         N 4-8 MPH.
TRANSPORT WINDS               S 5-7 MPH.          N 6-8 MPH.
MIXING HEIGHT                 NEAR SURFACE.       4000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR WED SEP 16        FAIR.
OUTLOOK FOR THU SEP 17        POOR.

VENTILATION INDEX (CATEGORY)  27 (POOR).          123 (POOR).
OUTLOOK FOR WED SEP 16        239 (POOR).
OUTLOOK FOR THU SEP 17        141 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM       96 (POOR)
ELLENSBURG     89 (POOR)
GOLDENDALE    114 (POOR)
TRI-CITIES    139 (POOR)
WALLA WALLA   124 (POOR)
YAKIMA        169 (POOR)
BEND          312 (FAIR)
PRINEVILLE    339 (FAIR)
ENTERPRISE    207 (POOR)
HERMISTON     101 (POOR)
JOHN DAY      451 (FAIR)
LA GRANDE     217 (POOR)
MADRAS        260 (POOR)
MEACHAM       107 (POOR)
PENDLETON     159 (POOR)
REDMOND       367 (FAIR)
SENECA        541 (FAIR)
THE DALLES    217 (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.
$$