Weather

A sudden change in temperature, cold air, windy days, poor air quality and hot, humid days are all known triggers for asthma.
Take your usual dose of reliever inhaler before going out on cold, dry days. If it is cold and windy, wearing a scarf over your face will help to warm up the air before you breathe it in. Try to avoid going out in the middle of the day on hot, smoggy days.
Cloudy sky

Thunderstorms

Thunderstorms can release large quantities of pollen, in very small particles, into the air. This can trigger asthma attacks for many people. It is best to stay inside with the windows closed during thunderstorms.