697
AUUS46 KPDT 191325
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PST WED NOV 19 2025

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

FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO

                              7:00 AM             AFTERNOON
SURFACE WINDS                 E 1-3 MPH.          N 4-8 MPH.
TRANSPORT WINDS               SE 3-4 MPH.         NE 5-10 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2500 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR THU NOV 20        POOR.
OUTLOOK FOR FRI NOV 21        POOR.

VENTILATION INDEX (CATEGORY)  25 (POOR).          97 (POOR).
OUTLOOK FOR THU NOV 20        68 (POOR).
OUTLOOK FOR FRI NOV 21        119 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 NW 1-3 MPH.         E 3-7 MPH.
TRANSPORT WINDS               NW 3-6 MPH.         E 4-8 MPH.
MIXING HEIGHT                 NEAR SURFACE.       3000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR THU NOV 20        POOR.
OUTLOOK FOR FRI NOV 21        POOR.

VENTILATION INDEX (CATEGORY)  27 (POOR).          89 (POOR).
OUTLOOK FOR THU NOV 20        51 (POOR).
OUTLOOK FOR FRI NOV 21        45 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 N 1-3 MPH.          E 2-5 MPH.
TRANSPORT WINDS               N 3-5 MPH.          S 8-11 MPH.
MIXING HEIGHT                 4000 FT MSL.        5000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR THU NOV 20        FAIR.
OUTLOOK FOR FRI NOV 21        FAIR.

VENTILATION INDEX (CATEGORY)  40 (POOR).          139 (POOR).
OUTLOOK FOR THU NOV 20        96 (POOR).
OUTLOOK FOR FRI NOV 21        89 (POOR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 E 1-4 MPH.          N 3-6 MPH.
TRANSPORT WINDS               SE 3-5 MPH.         NE 4-8 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2500 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR THU NOV 20        POOR.
OUTLOOK FOR FRI NOV 21        POOR.

VENTILATION INDEX (CATEGORY)  29 (POOR).          88 (POOR).
OUTLOOK FOR THU NOV 20        60 (POOR).
OUTLOOK FOR FRI NOV 21        151 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      418 (FAIR)
ELLENSBURG    221 (POOR)
GOLDENDALE    271 (POOR)
TRI-CITIES     97 (POOR)
WALLA WALLA    68 (POOR)
YAKIMA         86 (POOR)
BEND          183 (POOR)
PRINEVILLE    261 (POOR)
ENTERPRISE    141 (POOR)
HERMISTON     108 (POOR)
JOHN DAY      258 (POOR)
LA GRANDE     163 (POOR)
MADRAS         54 (POOR)
MEACHAM       123 (POOR)
PENDLETON     119 (POOR)
REDMOND       104 (POOR)
SENECA        340 (FAIR)
THE DALLES    314 (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.
$$