Most people with asthma
have several allergic triggers which result in asthma flares. These allergic triggers are many, but include dust mites, cockroaches, mice, pollen, pet
dander, and fungal spores. Whenever the concentration of of these agents is increased in the air that the asthmatic is breathing, this could trigger a flare.
In your case, where you have specifically noted an association between humid weather and asthma flares, what is likely going on is that the humidity and wet air allows dust mites and fungi to proliferate, leading to higher concentrations of these contaminants in the air and causing a flair. To support this hypothesis is the observation that many asthmatics get better if they have air conditioning in their homes, presumably because the cooler, drier air inhibits dust mite proliferation.
If these symptoms are particularly bothersome to you, you should talk to your primary care doctor
or your allergist. This is because you may need to think about increasing your dose of or adding a maintenance medication during this period of the year. Maintenance medications have the advantage of preventing flares and keeping your symptoms under control without having to use your rescue inhaler or limit your physical activity as you currently are doing.