When the temperature fluctuates drastically this can set off an asthma attack. For a lot of people this can occur when they go from a warm indoor environment to a much colder outdoor environment, this can lead to them experiencing wheezing and difficulty breathing. This can be disconcerting to an asthmatic as it may not immediately be apparent what’s set off a condition they thought they understood so well! In these cases they might not react quickly enough and a slightly reaction could turn severe putting their health in jeopardy.
Unfortunately for asthmatics, there are some parts of the world where the temperature fluctuates so much and so drastically through a short period of time that it might trigger a reaction. In these cases there may be very little that a sufferer can do as they may be stuck outdoors or simply in the environment in general with no way of countering the temperature change.
As I say, the best way of dealing with this possibility it to be as prepared as you can be all the time. Have an inhaler, be aware of weather forecast, know what to do in an emergency and know where the nearest hospital is. Better to be safe than sorry, after all.