The weather on Skyros island is the Mediterranean, which means mild winters and hot summers. November to February are the cold months and it is raining a lot. These rains provide the necessary conditions to grow so much greenery on the island. The winter blows a lot in winter and this leads to winter storms, which can be quite fierce.
Therefore, you are advised to stay indoors when winter storms blow in winter. The summer months offer very light rain and comfortable temperatures. June to September are the hottest months, with the temperature varying between 40°C in July to 28°C in September. Rains are few in summer, but northern winds blow frequently, so beaches should be avoided these days. Have in mind that beaches on the island are not organized and there are no lifeguards on windy days.