Shimada, Japan experiences a temperate climate with distinct seasonal variations. Winters are cool and occasionally cold, with temperatures ranging from around freezing to the mid-teens in January and December. As spring approaches, temperatures gradually warm up, reaching averages of around 15°C by April and May. Summers are hot and humid, with highs often above 30°C from June to August. Autumn brings a return to milder conditions, with temperatures dropping back down into the cool range by November.