BY A STAFF REPORTER: Due to cyclone 'Ashni', a yellow alert has been issued in four districts of Kerala till Sunday. According to the India Meteorological Department, a yellow alert has been issued in Idukki, Kottayam, Ernakulam and Malappuram districts on Thursday. A similar alert will be issued in Alappuzha, Ernakulam and Idukki on Friday. On the other hand, Kollam, Pathanamthitta, Alappuzha, Kottayam and Idukki will receive heavy to very heavy rainfall on Saturday and Thiruvananthapuram, Kollam, Alappuzha, Kottayam, Ernakulam and Idukki on Sunday.