NBM Ag/Backyard Burn Bulletin Guidance
Model Run Time:  2026-08-25 15Z

Day/Date/TimePortlandSalemEugene
Tue Aug 25th 9:00 amNo BurnNo BurnNo Burn
Tue Aug 25th 10:00 amNo BurnNo BurnNo Burn
Tue Aug 25th 11:00 amNo BurnNo BurnNo Burn
Tue Aug 25th 12:00 pmNo BurnNo BurnNo Burn
Tue Aug 25th 1:00 pmBurnBurnBurn
Tue Aug 25th 2:00 pmBurnBurnBurn
Tue Aug 25th 3:00 pmBurnBurnBurn
Tue Aug 25th 4:00 pmBurnBurnBurn
Tue Aug 25th 5:00 pmBurnBurnNo Burn
Tue Aug 25th 6:00 pmBurnNo BurnNo Burn
Tue Aug 25th 7:00 pmNo BurnNo BurnNo Burn
Tue Aug 25th 8:00 pmNo BurnNo BurnNo Burn
Tue Aug 25th 9:00 pmNo BurnNo BurnNo Burn
Tue Aug 25th 10:00 pmNo BurnNo BurnNo Burn
Tue Aug 25th 11:00 pmNo BurnNo BurnNo Burn
Wed Aug 26th 12:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 1:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 2:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 3:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 4:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 5:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 6:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 7:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 8:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 9:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 11:00 amNo BurnNo BurnNo Burn
Wed Aug 26th 2:00 pmNo BurnBurnBurn
Wed Aug 26th 5:00 pmBurnBurnBurn
Wed Aug 26th 8:00 pmNo BurnNo BurnNo Burn
Wed Aug 26th 11:00 pmNo BurnNo BurnNo Burn
Thu Aug 27th 2:00 amNo BurnNo BurnNo Burn
Thu Aug 27th 5:00 amNo BurnNo BurnNo Burn
Thu Aug 27th 8:00 amNo BurnNo BurnNo Burn
Thu Aug 27th 11:00 amBurnBurnNo Burn
Thu Aug 27th 2:00 pmBurnBurnNo Burn
Thu Aug 27th 5:00 pmBurnBurnBurn
Thu Aug 27th 8:00 pmNo BurnNo BurnNo Burn
Thu Aug 27th 11:00 pmNo BurnNo BurnNo Burn
Fri Aug 28th 2:00 amNo BurnNo BurnNo Burn
Fri Aug 28th 5:00 amNo BurnNo BurnNo Burn
Fri Aug 28th 8:00 amNo BurnNo BurnNo Burn
Criteria:
Field-burning season (July 5 - September 30):
Mixing Height >= 3000 feet, with Surface Winds >= 5 mph and Transport Winds >= 7 mph.
Rest of year:
Mixing Height >= 2000 feet or Ventilation Index >= 20, with Surface Winds >= 5 mph and Transport Winds >= 7 mph.

In addition (both seasons):
Transport wind direction greater than 10 and less than 350 degrees.
Ventilation Index = Mixing Height (ft) x Transport Wind (mph) / 1000.