512
AUUS46 KPDT 181225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT WED JUN 18 2025

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SW 8-15 MPH.        W 16-22 MPH.
TRANSPORT WINDS               SW 10-17 MPH.       W 18-25 MPH.
MIXING HEIGHT                 NEAR SURFACE.       7500 FT MSL.
DISPERSION CATEGORY           FAIR.               GOOD.
OUTLOOK FOR THU JUN 19        FAIR.
OUTLOOK FOR FRI JUN 20        GOOD.

VENTILATION INDEX (CATEGORY)  221 (POOR).         886 (GOOD).
OUTLOOK FOR THU JUN 19        281 (POOR).
OUTLOOK FOR FRI JUN 20        1050 (GOOD).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 W 3-7 MPH.          W 15-21 MPH.
TRANSPORT WINDS               W 5-10 MPH.         W 18-25 MPH.
MIXING HEIGHT                 NEAR SURFACE.       8000 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR THU JUN 19        POOR.
OUTLOOK FOR FRI JUN 20        GOOD.

VENTILATION INDEX (CATEGORY)  155 (POOR).         1000 (GOOD).
OUTLOOK FOR THU JUN 19        178 (POOR).
OUTLOOK FOR FRI JUN 20        913 (GOOD).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 N 2-2 MPH.          NW 10-12 MPH.
TRANSPORT WINDS               W 3-6 MPH.          W 11-13 MPH.
MIXING HEIGHT                 4000 FT MSL.        10500 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR THU JUN 19        FAIR.
OUTLOOK FOR FRI JUN 20        GOOD.

VENTILATION INDEX (CATEGORY)  76 (POOR).          569 (FAIR).
OUTLOOK FOR THU JUN 19        337 (FAIR).
OUTLOOK FOR FRI JUN 20        559 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 6-16 MPH.         W 13-19 MPH.
TRANSPORT WINDS               SW 10-17 MPH.       W 14-20 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6500 FT MSL.
DISPERSION CATEGORY           FAIR.               FAIR.
OUTLOOK FOR THU JUN 19        FAIR.
OUTLOOK FOR FRI JUN 20        GOOD.

VENTILATION INDEX (CATEGORY)  198 (POOR).         638 (GOOD).
OUTLOOK FOR THU JUN 19        267 (POOR).
OUTLOOK FOR FRI JUN 20        999 (GOOD).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      843 (GOOD)
ELLENSBURG    978 (GOOD)
GOLDENDALE   1017 (GOOD)
TRI-CITIES   1050 (GOOD)
WALLA WALLA   667 (GOOD)
YAKIMA        785 (GOOD)
BEND          746 (GOOD)
PRINEVILLE    631 (GOOD)
ENTERPRISE    768 (GOOD)
HERMISTON     940 (GOOD)
JOHN DAY     1050 (GOOD)
LA GRANDE     624 (GOOD)
MADRAS        758 (GOOD)
MEACHAM       423 (FAIR)
PENDLETON     693 (GOOD)
REDMOND       597 (FAIR)
SENECA       1050 (GOOD)
THE DALLES   1025 (GOOD)

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.
$$