Kanuma is the third day of the festival, Sankranti. According to Hindu mythology, on this day Lord Sri Krsihna lifted the Govardhana Hill (Govardhana Giri – Govardhana Giridhari is one of Krishnas names). Kanuma 2016 or Kanumu 2016 date is January 16.
Once Lord Indra, with his headstrong poured a heavy rain on Gokulam (Sri Krishnas place). People of Gokulam prayed to Krishna to save them from the cyclone. At that time Sri Krishna was just about 10 years. But without any fear, the Lord lifted the hill with his small finger.
Thus Indra realized that Sri Krishna is non other than Lord Sri Maha Vishnu and bowed on the Lords his feet.