The missing fishermen had put out to sea from Vizhinjam and Shaktikulnagara in Kollam. (Representational)

Seven fishermen are missing and relief camps have been opened in two districts as heavy rains lashed several parts of Kerala for the second day on Friday under the influence of the southwest monsoon.

A Red alert (extremely heavy rains) was issued in Idukki, Kozhikode, Wayanad, Malappuram and Kannur districts with over 20 cm rains being forecast from July 19-22, while the northernmost Kasaragod district will come under the alert on Saturday, according to IMD.

The weathermen are hopeful that the second spell of the monsoon, which started Wednesday, will bring in heavy rains to the state, which had recorded 46 per cent deficiency till July 15.

The latest Met Department update said that while Peermede in Idukki and Kozhikode each recorded 15 cm of rainfall, Ponnani in Malappuram recorded 14 cm.

Trees were uprooted in many places, some of them falling on homes and damaging the dwellings.

The missing fishermen had put out to sea from nearby Vizhinjam and Shaktikulnagara in Kollam in separate boats.

While Coastal police sources said a search had been launched, local people protested, saying no efforts were being taken to trace them.

Coastal police told PTI that the rough sea was making it difficult to conduct search operations, but that their boats had already been deployed.

Thiruvananthapuram District Collector K Gopalakrishnan met them, assured all help to bring back safely the four fishers from Vizhinjam and said helicopters were being used to trace them.

In Kollam, three fishermen went missing after their boat overturned in the choppy waters.

Two others in the boat, who swam to safety, were rescued and have been hospitalised.

Many low lying areas in Kozhikode were waterlogged with the busy Mavoor road remaining underwater for over six hours and water entering some hotels and nearby buildings.

In Kannur, people were shifted to relief camps as water entered nearly 30 houses at Thavakkara near the railway station.

A well caved in at Malappuram, while in Chellanam area in Kochi, water entered several homes in the low lying areas. Some places in Malappuram, Thrissur, Ernakulam and Kottayam districts received rainfall of over 12 cm.

In the high range Idukki district, landslips in some places affected vehicular movement on the Ettumanoor-Peerumedu Road for an hour.

Idukki District Collector H Dineshan told PTI that all precautions have been taken to deal with any situation.

Pilgrims visiting the famous Lord Ayyappa temple in Sabarimala in Pathanamthitta district, which has been opened for the five-day monthly pooja, were put to difficulties due to incessant rain.

"Due to heavy rain since yesterday, the Pamba area was flooded. But now the water is receding," said a top official in-charge of Disaster Management Authority in Pathanamthita district.

Kasargod District Collector has declared a holiday tomorrow for all educational institutions, including professional colleges in the district in the wake of heavy rains and red alert.

With the southwest monsoon intensifying, the IMD has issued orange and yellow alerts across various districts. Yellow alert has been issued for Thiruvananthapuram, Kollam, Pathanamthitta, Alappuzha, Kottayam, Ernakulam, Thrissur, Palakkad and Kasargod districts.

The State Disaster Management Authority has asked all the departments to open control rooms at Taluk headquarters. The Monsoon had set in over the state on June 8, after a week long delay.