Read about the “annual miracles which takes place at Mount Tabor, especially about the Holy Cloud, which just about every year after the Vigil it occurs by covering Mount Tabor. Specifically it usually comes from Nazareth, an all-white cloud at a very low height, and it stays above the Church of the Transfiguration covering all the people, and it often descends to the earth.
This only happens when the Orthodox Christian pilgrims chant. When they don’t chant, nothing comes….”
on John Sanidopoulos’ blog MYSTAGOGY (here)