"Though southwest monsoon has become weak across the state, it is expected to gain momentum during the weekend. The fishermen have been warned against venturing into the sea, as strong offshore wind from northwest reaching 45 to 55 km per hour is likely to hit the coastal regions in the state, as well as Lakshadweep, during the next 24 hours," said K Santosh, director, Indian Meteorological Department (IMD) here on Wednesday.

IMD officials said rains are never uniform during the season. Many factors contribute to the distribution of showers. It could be change in wind pressure or seasonal changes in atmospheric circulation and precipitation associated with the asymmetric heating of land and sea. A rampant climate change with increasing deforestation, mining and other infrastructure development activities can also be a reason, the officials added.

IMD senior scientist B P Yadav said, "Rains may not continue to be vigorous every day. After a spell of heavy rains, it might weaken as it would advance for a northward shift to Karnataka and Goa."

Heavy showers can be expected in Kerala by the weekend," he added.