The 'orange alert' was issued for Ernakulam, Idukki, Thrissur, Palakkad, Malappuram, Kozhikode, Wayanad, Kannur, and Kasaragod.
A 'yellow alert' was issued for the remaining five districts.
An 'orange alert' indicates "very heavy rainfall" between 11 cm and 20 cm, while a 'yellow alert' denotes "heavy rainfall" between 6 cm and 11 cm.
The IMD also forecast moderate rainfall across the state, with strong surface winds occasionally gusting up to 40 kmph in one or two places.
In Palakkad, rising water levels in several dams prompted authorities to open shutters to release excess water.
According to the district administration, the affected dams include Malampuzha, Mangalam, Siruvani, Meenkara, and Pothundi.
Meanwhile, the Irrigation Design and Research Board (IDRB) issued 'danger alerts' for the Manimala and Mogral rivers in Pathanamthitta and Kasaragod districts, respectively, as water levels rose significantly.
Residents living along the riverbanks were advised to stay alert and be prepared to move to safer locations as instructed by the authorities.
Additionally, the IMD cautioned against fishing along the Kerala-Karnataka coast till July 23 due to expected rough weather and strong winds ranging between 40 and 60 kmph.
It also forecast winds between 40 and 50 kmph at isolated places across Kerala till July 24 and advised the public to remain cautious.
Fisherfolk and coastal residents were advised to remain vigilant.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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