Most areas of Java forecast to experience such weather include Banten, West Java, Central Java, Yogyakarta, and East Java.
Based on forecasts from the BMKG website quoted here on Friday, the cyclonic circulation in the Karimata Strait and the Pacific Ocean in northern Papua forms a convergence zone or area where prevailing winds meet.
Such condition extends from North Kalimantan to West Kalimantan, from the Malay Peninsula to West Sumatra, and from the Sulawesi Sea to Central Sulawesi and northern Papua to the northern waters of Halmahera.
The convergence is able to increase the potential of rain clouds forming around the cyclonic circulation area and along the convergence area.
According to the BMKG forecast, areas likely to experience heavy rain accompanied by lightning or strong winds today are Aceh, North Sumatra, West Sumatra, Riau, Bengkulu, Jambi, South Sumatra, and Lampung.
In addition, the same condition is forecast to occur in Bali, West Nusa Tenggara, West Kalimantan, Central Kalimantan, North Kalimantan, East Kalimantan, North Sulawesi, Gorontalo, Central Sulawesi, West Sulawesi, Southeast Sulawesi, North Maluku, Maluku, West Papua, and Papua.
Moreover, the BMKG has issued a warning that heavy rains of the alert category could lash from today to Saturday morning in several areas, in Aceh, North Sumatra, West Sumatra, Jambi, South Sumatra, DKI Jakarta, West Java, Central Java, Yogyakarta, East Java, West Nusa Tenggara, and North Kalimantan.
North Sulawesi, West Sulawesi, Central Sulawesi, and North Sulawesi are also included in the alert category for the risk of flooding owing to heavy rains.
Related news: Several provinces to enter dry season in April, BMKG forecasts
Related news: BMKG forecasts heavy rainfall in parts of Indonesia's regions