By HIMANI CHANDEL The Municipal Corporation of Delhi (MCD) is facing tough time with the arrival of early arrival of monsoon this year as the weather has become conducive for mosquito breeding. According to health officials of the civic body, the rains have cooled off the summer heat but are also serving as a catalyst for mosquito breeding. "This year, we did not experience much heat in the summer which has disturbed the ecological balance and the natural eradication of mosquitoes," municipal health officer (MHO) N.K. Yadav said.