THIRUVANANTHAPURAM: Yellow alert has been announced in eight districts today due to the possibility of rise in temperature. According to the Indian Meteorological Department, the temperature may rise up to 38 degrees in Palakkad, Kollam and Pathanamthitta districts, 37 degrees in Thrissur and 36 degrees in Kottayam, Malappuram, Kozhikode and Kasaragod districts.