The sun is present and warm. While this sentence may seems obvious, in some region, the sun and warmth even in the summer is not guaranteed for a week straight. While in Santorini, it generally seems always a perfect sunny weather condition. On the counterpart, I would not be surprise if the island has a challenge with water despite being surrounded by the sea. Many sections of the island has very low profile bushes and little tall trees, this typically confirms the island faces very little precipitation period in the summer. Bring sunscreen my friend.
Santorini is also a good place to see beautiful sunsets. Many will go to Oia, other will go the lighthouse but other options are available in between on the west side of the island to admire the sun going down in the horizon.