Hello,,, yes in allergic rhinitis you see seasonal variation, it's mainly because pollens from trees during summer and pollen from grass during rainy season usually acts as allergens and triggers allergic reactions like,, rhinitis, itching in throat, sneezing, even weezing (seasonal asthma) if a person is sensitive to these. Even though it has no cure It's better avoided by avoiding these allergens (not going to these places) antihistamines like cetrizine will help you to prevent attack.