na-adjective
Describes something that occurs, changes, or is typical of a particular season. Often used with nouns like 変化 (change), 商品 (product), 仕事 (work), or 傾向 (trend).
この仕事は季節的なものなので、冬は忙しいです。
This work is seasonal, so it's busy in winter.
季節的な気温の変化に注意してください。
Please be careful of seasonal temperature changes.