679
AUUS46 KPDT 051325
DDOPDT

DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PST FRI DEC  5 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 3-7 MPH.         SW 20-28 MPH.
TRANSPORT WINDS               S 3-7 MPH.          SW 20-29 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2000 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR SAT DEC 6         GOOD.
OUTLOOK FOR SUN DEC 7         FAIR.

VENTILATION INDEX (CATEGORY)  29 (POOR).          184 (POOR).
OUTLOOK FOR SAT DEC 6         778 (GOOD).
OUTLOOK FOR SUN DEC 7         148 (POOR).

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

                              7:00 AM             AFTERNOON
SURFACE WINDS                 SE 1-4 MPH.         W 11-23 MPH.
TRANSPORT WINDS               E 2-4 MPH.          W 11-22 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2000 FT MSL.
DISPERSION CATEGORY           POOR.               FAIR.
OUTLOOK FOR SAT DEC 6         GOOD.
OUTLOOK FOR SUN DEC 7         POOR.

VENTILATION INDEX (CATEGORY)  27 (POOR).          85 (POOR).
OUTLOOK FOR SAT DEC 6         561 (FAIR).
OUTLOOK FOR SUN DEC 7         140 (POOR).

FOR THE GRANDE RONDE RIVER VALLEY

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 4-6 MPH.          S 10-14 MPH.
TRANSPORT WINDS               S 6-8 MPH.          S 13-18 MPH.
MIXING HEIGHT                 4000 FT MSL.        4000 FT MSL.
DISPERSION CATEGORY           POOR.               POOR.
OUTLOOK FOR SAT DEC 6         GOOD.
OUTLOOK FOR SUN DEC 7         FAIR.

VENTILATION INDEX (CATEGORY)  78 (POOR).          152 (POOR).
OUTLOOK FOR SAT DEC 6         592 (FAIR).
OUTLOOK FOR SUN DEC 7         264 (POOR).

FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS

                              7:00 AM             AFTERNOON
SURFACE WINDS                 S 4-8 MPH.          SW 21-31 MPH.
TRANSPORT WINDS               SW 7-10 MPH.        SW 22-29 MPH.
MIXING HEIGHT                 NEAR SURFACE.       2500 FT MSL.
DISPERSION CATEGORY           POOR.               GOOD.
OUTLOOK FOR SAT DEC 6         GOOD.
OUTLOOK FOR SUN DEC 7         FAIR.

VENTILATION INDEX (CATEGORY)  53 (POOR).          252 (POOR).
OUTLOOK FOR SAT DEC 6         805 (GOOD).
OUTLOOK FOR SUN DEC 7         193 (POOR).

SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM      134 (POOR)
ELLENSBURG     50 (POOR)
GOLDENDALE    256 (POOR)
TRI-CITIES     92 (POOR)
WALLA WALLA   179 (POOR)
YAKIMA         31 (POOR)
BEND          330 (FAIR)
PRINEVILLE     97 (POOR)
ENTERPRISE    160 (POOR)
HERMISTON     155 (POOR)
JOHN DAY      215 (POOR)
LA GRANDE     114 (POOR)
MADRAS        355 (FAIR)
MEACHAM       206 (POOR)
PENDLETON     266 (POOR)
REDMOND       132 (POOR)
SENECA        356 (FAIR)
THE DALLES    189 (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.
$$