TEMPO.CO, Jakarta - The Meteorology, Climatology and Geophysics Agency (BMKG) warns the people to be aware of heavy rains with lightning and strong wind in a number of regions in Indonesia on Saturday, Nov. 20.

Based on the weather early warning system, BMKG predicted that it will occur in Aceh, Bali, Bangka Belitung, Banten, Bengkulu, Jakarta, Gorontalo, Jambi, West Java, East Java, most of Kalimantan provinces, and Lampung. As well as in West Nusa Tenggara, East Nusa Tenggara, Papua, Riau, West Sulawesi, South Sulawesi, Central Sulawesi, Southeast Sulawesi, West Sumatra and South Sumatra.

Earlier, BMKG chief Dwikorita Karnawati reminded the public of La Nina phenomenon at the end of this year. Based on last year's La Nina, BMKG study shows there will be an increase of rainfall from November to January, specially in South Sumatra, Java, Bali, NTT, South Kalimantan, and South Sulawesi.

Based on that, this year's La Nina will be predictably similar and affect the increase of monthly rainfall at around 20-70 percent above normal. "Due to the potential increase of rainfall in this rainy season period, it is important to increase the alertness and readiness as the high rainfall will be potential to trigger hydrometeorological disasters," said Dwikorita.

In addition, BMKG issues an early warning of tidal flooding in the northern coast area in Java Island on November 18-25, while the heavy rain will occur on November 19-23 in the noon and afternoon.

Based on the data of water level montoring, there are several areas that must be watched out for the tidal prediction in the economic buffer zones of the north coast of Java. Those include Tangerang, Jakarta, Bekasi, Karawang, Subang, Indramayu, Cirebon, Brebes, Pemalang, Pekalongan, Batang, Kendal, Semarang, Demak, Jepara, and Gresik.

BMKG stated that tidal flooding is a common phenomenon that often occurs, especially on the north coast of Java. However, the presence of maximum tidal conditions during the full moon phase, along with rainfalls will cause a more significant increase in tidal flood.

Read: BNPB Warns About La Nina Impact in Indonesia

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