The first Friday (July 22) in the Tamil month of Aadi (July 17 – Aug 16) is celebrated as Aadi Velli (Aadi Friday) to glorify the Mother Goddess or Amman and seek her blessings.
The month of Aadi is the start of the Sun’s southern journey and onset of monsoon season. The six months starting with Aadi are the night of the Devas (celestial gods).
The subsequent four Fridays are also celebrated in glory of Amman. In fact throughout the Aadi month are a string of temple festivals.
And Hindus avoid carrying out auspicious events like weddings, starting businesses, moving house etc in this month.
It is a month dedicated to serious worship and seeking Divine blessings.