831
AUUS46 KPDT 281225
DDOPDT
DAILY DISPERSION OUTLOOK
NATIONAL WEATHER SERVICE PENDLETON OR
525 AM PDT THU MAY 28 2026
*** AIR DISPERSION CATEGORIES: GOOD, FAIR, POOR ***
FOR THE COLUMBIA BASIN FROM PENDLETON TO WALLA WALLA AND PASCO
7:00 AM AFTERNOON
SURFACE WINDS S 3-7 MPH. NE 4-7 MPH.
TRANSPORT WINDS S 3-7 MPH. NE 8-11 MPH.
MIXING HEIGHT NEAR SURFACE. 6000 FT MSL.
DISPERSION CATEGORY POOR. FAIR.
OUTLOOK FOR FRI MAY 29 GOOD.
OUTLOOK FOR SAT MAY 30 FAIR.
VENTILATION INDEX (CATEGORY) 36 (POOR). 354 (FAIR).
OUTLOOK FOR FRI MAY 29 878 (GOOD).
OUTLOOK FOR SAT MAY 30 656 (GOOD).
FOR THE UPPER YAKIMA VALLEY INCLUDING YAKIMA...UNION GAP...
SELAH...AND NACHES AREA
7:00 AM AFTERNOON
SURFACE WINDS NW 2-5 MPH. NE 3-6 MPH.
TRANSPORT WINDS NW 4-7 MPH. NE 7-9 MPH.
MIXING HEIGHT NEAR SURFACE. 7500 FT MSL.
DISPERSION CATEGORY POOR. FAIR.
OUTLOOK FOR FRI MAY 29 GOOD.
OUTLOOK FOR SAT MAY 30 FAIR.
VENTILATION INDEX (CATEGORY) 64 (POOR). 404 (FAIR).
OUTLOOK FOR FRI MAY 29 584 (FAIR).
OUTLOOK FOR SAT MAY 30 405 (FAIR).
FOR THE GRANDE RONDE RIVER VALLEY
7:00 AM AFTERNOON
SURFACE WINDS NW 2-5 MPH. S 5-7 MPH.
TRANSPORT WINDS N 7-9 MPH. SE 8-12 MPH.
MIXING HEIGHT NEAR SURFACE. 8000 FT MSL.
DISPERSION CATEGORY POOR. FAIR.
OUTLOOK FOR FRI MAY 29 GOOD.
OUTLOOK FOR SAT MAY 30 FAIR.
VENTILATION INDEX (CATEGORY) 88 (POOR). 207 (POOR).
OUTLOOK FOR FRI MAY 29 487 (FAIR).
OUTLOOK FOR SAT MAY 30 441 (FAIR).
FOR THE BASE OF THE NORTHERN BLUE MOUNTAINS
7:00 AM AFTERNOON
SURFACE WINDS S 2-6 MPH. N 4-8 MPH.
TRANSPORT WINDS S 5-7 MPH. NE 8-11 MPH.
MIXING HEIGHT NEAR SURFACE. 4500 FT MSL.
DISPERSION CATEGORY POOR. FAIR.
OUTLOOK FOR FRI MAY 29 GOOD.
OUTLOOK FOR SAT MAY 30 FAIR.
VENTILATION INDEX (CATEGORY) 31 (POOR). 261 (POOR).
OUTLOOK FOR FRI MAY 29 721 (GOOD).
OUTLOOK FOR SAT MAY 30 559 (FAIR).
SELECT AFTERNOON FORECAST VENTILATION INDICES FOR SOME CITIES
CLE ELUM 221 (POOR)
ELLENSBURG 229 (POOR)
GOLDENDALE 529 (FAIR)
TRI-CITIES 430 (FAIR)
WALLA WALLA 210 (POOR)
YAKIMA 414 (FAIR)
BEND 659 (GOOD)
PRINEVILLE 700 (GOOD)
ENTERPRISE 426 (FAIR)
HERMISTON 391 (FAIR)
JOHN DAY 1002 (GOOD)
LA GRANDE 305 (FAIR)
MADRAS 751 (GOOD)
MEACHAM 253 (POOR)
PENDLETON 366 (FAIR)
REDMOND 773 (GOOD)
SENECA 1050 (GOOD)
THE DALLES 585 (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.
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