Chennai, Aug 20 : Heavy rains are likely in 17 districts of Tamil Nadu for the next two days due to a cyclonic circulation prevailing over the sea, the Regional Meteorological Centre here forecast on Sunday. The fishermen are also advised not to venture into the sea in the next two days due to the cyclonic circulation and squally winds are likely to prevail from 45 kmph to 55 kmph in the same period over the south Tamil Nadu coast, Gulf of Mannar and adjoining Comorin area, as well as the southwest Bay of Bengal. Heavy rains are expected in The Nilgiris, Tiruvarur, Thanjavur, Nagapattinam, Myladuthurai, Ariyalur,Cuddalore, Coimbatore, Tiruppur, Theni, Dindigul, Madurai, Sivaganga, Perambalur, Kallakurichi, Pudukottai, and Tiruchi districts. Chennai is also likely to receive rain for the next two days in the evenings with moderate spells. Thunderstorms are also likely to lash Chennai in the next few days. However, Chennai is expected to have bright daytime and maximum temperature at Nungambakkam and Meenambakkam weather stations are likely to be 36 degrees Celsius. /IANS