Shukla Paksha Panchami during Sawan month is observed as Nag Panchami. Usually Nag Panchami day falls two days after Hariyali Teej. Currently Nag Panchami falls in month of July and August in English calendar. Women worship Nag Devta and offer milk to snakes on this day. Women also pray for the wellness of their brothers and family.
Nag Panchami is a traditional worship of serpent Gods observed by Hindus throughout India.
In Hindu calendar, some days are considered significant to worship serpent Gods and Panchami Tithi especially during Shravan month is considered highly auspicious to worship serpent Gods. Nag Panchami is one of those significant days and it observed on Shukla Paksha Panchami during Shravana month.
It is believed that any Puja offered to snakes would reach to the serpent Gods. Hence people worship live snakes on the day as representative of serpents Gods who are revered and worshipped in Hinduism.