538
AUUS46 KPDT 291325
DDOPDT
DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PST MON DEC 29 2025
*** AIR DISPERSION CATEGORIES: GOOD, FAIR, POOR ***
FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO
7:00 AM AFTERNOON
SURFACE WINDS NW 1-5 MPH. N 3-7 MPH.
TRANSPORT WINDS N 3-8 MPH. N 4-8 MPH.
MIXING HEIGHT NEAR SURFACE. NEAR SURFACE.
DISPERSION CATEGORY POOR. POOR.
OUTLOOK FOR TUE DEC 30 POOR.
OUTLOOK FOR WED DEC 31 POOR.
VENTILATION INDEX (CATEGORY) 27 (POOR). 44 (POOR).
OUTLOOK FOR TUE DEC 30 31 (POOR).
OUTLOOK FOR WED DEC 31 28 (POOR).
FOR THE UPPER YAKIMA VALLEY INCLUDING YAKIMA...UNION GAP...
SELAH...AND NACHES AREA
7:00 AM AFTERNOON
SURFACE WINDS NW 1-4 MPH. NW 1-4 MPH.
TRANSPORT WINDS NW 2-5 MPH. NW 2-5 MPH.
MIXING HEIGHT NEAR SURFACE. 2000 FT MSL.
DISPERSION CATEGORY POOR. POOR.
OUTLOOK FOR TUE DEC 30 POOR.
OUTLOOK FOR WED DEC 31 POOR.
VENTILATION INDEX (CATEGORY) 27 (POOR). 35 (POOR).
OUTLOOK FOR TUE DEC 30 30 (POOR).
OUTLOOK FOR WED DEC 31 26 (POOR).
FOR THE GRANDE RONDE RIVER VALLEY
7:00 AM AFTERNOON
SURFACE WINDS SE 5-10 MPH. S 9-15 MPH.
TRANSPORT WINDS S 8-14 MPH. S 15-20 MPH.
MIXING HEIGHT 4000 FT MSL. 4500 FT MSL.
DISPERSION CATEGORY POOR. FAIR.
OUTLOOK FOR TUE DEC 30 GOOD.
OUTLOOK FOR WED DEC 31 GOOD.
VENTILATION INDEX (CATEGORY) 114 (POOR). 282 (POOR).
OUTLOOK FOR TUE DEC 30 307 (FAIR).
OUTLOOK FOR WED DEC 31 249 (POOR).
FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS
7:00 AM AFTERNOON
SURFACE WINDS SE 2-5 MPH. NW 2-5 MPH.
TRANSPORT WINDS SE 3-7 MPH. NE 2-5 MPH.
MIXING HEIGHT NEAR SURFACE. NEAR SURFACE.
DISPERSION CATEGORY POOR. POOR.
OUTLOOK FOR TUE DEC 30 POOR.
OUTLOOK FOR WED DEC 31 POOR.
VENTILATION INDEX (CATEGORY) 30 (POOR). 32 (POOR).
OUTLOOK FOR TUE DEC 30 33 (POOR).
OUTLOOK FOR WED DEC 31 36 (POOR).
SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM 95 (POOR)
ELLENSBURG 25 (POOR)
GOLDENDALE 83 (POOR)
TRI-CITIES 70 (POOR)
WALLA WALLA 25 (POOR)
YAKIMA 29 (POOR)
BEND 54 (POOR)
PRINEVILLE 158 (POOR)
ENTERPRISE 25 (POOR)
HERMISTON 51 (POOR)
JOHN DAY 137 (POOR)
LA GRANDE 265 (POOR)
MADRAS 32 (POOR)
MEACHAM 63 (POOR)
PENDLETON 42 (POOR)
REDMOND 78 (POOR)
SENECA 135 (POOR)
THE DALLES 167 (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.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page