Chennai, July 21 : A second flood warning in southern districts of Tamil Nadu, including Madurai district is expected following incessant rains increasing the water levels in Vaiga dam. A statement from the state water resources minister's office said that the department will issue the second flood alert only if the water level in Vaiga touches 68.5 ft. The southern districts of the state have been experiencing intermittent rains for the past few days and weather has been cloudy. The water levels in the catchment areas of prominent dams have received good water flow. The water level of Vaigai dam crossed 66 ft on July 9 and this led to the issuing of the first flood warning. On Tuesday, the water level of Vaigai dam touched 68.29 ft against its maximum of 71 ft. The third warning is expected if it breaches 69 ft. The inflow has reduced and hence the water level has not yet touched the 68.5 ft mark to issue the second flood warning. The catchment area of Mullaperiyar dam has also been receiving heavy rains for the past couple of days and the inflow in the dam has also increased. However, no flood alert has been issued for Mullaperiyar dam. /IANS