Air Pollution Forecasts

Air pollution (PM₁₀) forecasts are issued from 1 May to 31 August for Christchurch, Timaru, Rangiora, Kaiapoi and Ashburton. As this type of air pollution is mainly caused by home heating by wood and coal, high air pollution nights (days over 50 μg/m³) very rarely happen outside this period.

In winter, air pollution levels can get high when smoke from chimneys doesn’t get blown away and is trapped under an inversion layer. This happens during still, cold and often frosty nights. This dependence on weather conditions makes air pollution forecasts possible.