Heavy downpour is likely in most parts of Odisha in the next few days, as a low pressure area is set to form over the Bay of Bengal, the Met office said here on Thursday. The low pressure area, likely to form over northeast Bay of Bengal by August 4, will trigger rainfall in districts like Kalahandi, Nabarangpur, Koraput, Malkangiri and Mayurbhanj and the intensity will increase from Friday, it said. On August 3 and 4, heavy rainfall is also expected in Bhadrak, Keonjhar, Kendrapara, Jagatsinghpur, Ganjam, Puri, Kalahandi, Kandhamal, Balasore and Bhadrak districts. Thereafter, several parts of Jajpur, Mayurbhanj, Bhadrak, Kendrapara, Kalahandi, Keonjhar, Dhenkanal, Balasore, Nabarangpur, Jagatsinghpur, Khurda, Sambalpur, Deogarh and Sonepur districts will experience heavy to very heavy rainfall till August 6, the MeT office said. Under the influence of the system, high velocity winds are likely to sweep coastal and adjoining districts of Odisha. Fishermen have been advised not to venture into the sea along and off the coast and adjoining central Bay of Bengal on August 4 and 5, it said.The catchment areas of rivers like Mahanadi, Brahmani, Baitarani, Budhabalanga and Subarnarekha may receive heavy precipitation between August 3 and 6. As most parts of Odisha received rainfall in the last few days, the quantum of rainfall deficit in the state has come down to 17.7% from around 32% recorded on July 24, officials said, expressing hope that the deficit will further reduce in the next few days.