The ancient Akrotiri extends under modern Akrotiri, and therefore to the caldera wall. The pyroclastic flow and blast are very erratic. Wood can be vaporized only metres away from a place where paper is unburned. And that can occur many miles from the source, even for a small explosion like Mt St Helens or Pelee. The sun is covered and does not shine to the sight of men.
Life is no longer possible when the sun is concealed behind the clouds.
Ra has turned his face from mankind. No one knows when iot is midday. One's shadow is not discernible. The Sun in the heavens resembles the moon. After the ashfall, Minoan art took on a hybrid Grecianised style.