935
AUUS46 KPDT 011225
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT WED OCT  1 2025

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 4-9 MPH.          W 7-10 MPH.
TRANSPORT WINDS               S 5-10 MPH.         SW 9-12 MPH.
MIXING HEIGHT                 NEAR SURFACE.       5000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR THU OCT 2         FAIR.
OUTLOOK FOR FRI OCT 3         FAIR.

VENTILATION INDEX (CATEGORY)  47 (POOR).          345 (FAIR).
OUTLOOK FOR THU OCT 2         122 (POOR).
OUTLOOK FOR FRI OCT 3         314 (FAIR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 4-8 MPH.          SW 9-13 MPH.
TRANSPORT WINDS               S 6-9 MPH.          SW 15-20 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR THU OCT 2         FAIR.
OUTLOOK FOR FRI OCT 3         FAIR.

VENTILATION INDEX (CATEGORY)  68 (POOR).          720 (GOOD).
OUTLOOK FOR THU OCT 2         220 (POOR).
OUTLOOK FOR FRI OCT 3         254 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 7-12 MPH.         S 12-16 MPH.
TRANSPORT WINDS               S 9-13 MPH.         S 21-26 MPH.
MIXING HEIGHT                 4000 FT MSL.        9000 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR THU OCT 2         FAIR.
OUTLOOK FOR FRI OCT 3         FAIR.

VENTILATION INDEX (CATEGORY)  199 (POOR).         1050 (GOOD).
OUTLOOK FOR THU OCT 2         218 (POOR).
OUTLOOK FOR FRI OCT 3         457 (FAIR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 5-10 MPH.         W 7-9 MPH.
TRANSPORT WINDS               S 7-13 MPH.         SW 9-15 MPH.
MIXING HEIGHT                 NEAR SURFACE.       6000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR THU OCT 2         POOR.
OUTLOOK FOR FRI OCT 3         FAIR.

VENTILATION INDEX (CATEGORY)  126 (POOR).         557 (FAIR).
OUTLOOK FOR THU OCT 2         115 (POOR).
OUTLOOK FOR FRI OCT 3         327 (FAIR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      455 (FAIR)
ELLENSBURG    681 (GOOD)
GOLDENDALE    543 (FAIR)
TRI-CITIES    364 (FAIR)
WALLA WALLA   513 (FAIR)
YAKIMA        779 (GOOD)
BEND         1050 (GOOD)
PRINEVILLE   1028 (GOOD)
ENTERPRISE   1050 (GOOD)
HERMISTON     220 (POOR)
JOHN DAY     1050 (GOOD)
LA GRANDE    1050 (GOOD)
MADRAS       1000 (GOOD)
MEACHAM       846 (GOOD)
PENDLETON     425 (FAIR)
REDMOND      1050 (GOOD)
SENECA       1050 (GOOD)
THE DALLES    430 (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.
$$