The Meteorology, Climatology and Geophysics Agency (BMKG) has warned residents of 13 provinces over the potential for heavy rainfall in the next seven to 10 days.

BMKG head Dwikorita Karnawati said a weather phenomenon called Madden Julian Oscillation (MJO) was occurring in the air surrounding the archipelago, bringing extra water vapor to form clouds in the sky of the western and central part of the country.

“Although some parts of Indonesia have entered the dry season, other parts are still in transition from the rainy season to the dry season,” said Dwikorita in Jakarta on Sunday as reported by kompas.com.

She has warned people in Aceh, North Sumatra, West Sumatra, Central Kalimantan, Central Java, Yogyakarta, North Sulawesi, Southeast Sulawesi, West Sulawesi, North Maluku, Maluku, West Papua and Papua to stay alert concerning this forecast.

Besides rainfall, she also warned of lightning and thunder in the next two days in Central Sumatra, east coast of Sumatra, Banten and northern West Java.

Strong winds and tornadoes may also knock down trees and billboards.

She also said tropical cyclone Flamboyan may also cause high tide in the next two to three days.

“We suggest postponing fishing activities until the waves subside,” she said.

She said 4-meter waves would be seen in waters to the south of Java and to the west of Lampung. (gis/swd)