BMKG Predicts Early Rainy Season In November

JAKARTA - The Meteorology, Climatology and Geophysics Agency (BMKG) predicts that the start of the rainy season in Indonesia will occur in November 2023 or later than usual.

"The start of the rainy season is predicted to occur in November 2023. However, due to the high climate diversity in Indonesia, the start of the rainy season does not occur simultaneously in all regions," said BMKG Head Dwikorita Karnawati in a press conference reported by ANTARA, Friday, September 8.

Dwikorita said that currently most parts of Indonesia are still experiencing the dry season. This condition is influenced by the El Nino phenomenon in the Pacific Ocean, mainly influenced by the Australian Mosun wind.

El Nino's position is in a moderate phase since the end of June 2023 and currently the El Nino index is at +1.54. El Nino's condition is moderately predicted to last until early 2024.

Meanwhile, in the Indian Ocean, anomalous monitoring of sea level temperatures shows a positive Indian Ocean Dipole (IOD) condition with a value of +1.527 and is predicted to remain positive until the end of 2023.

According to him, the meaning of the positive IOD and moderate El Nino has an effect on reducing rainfall in the Indonesian archipelago.

"So the dryness of the dry season today is in accordance with the predictions of last February, due to the influence of both, El Nino in the Pacific Ocean and the positive IOD from the Indian Ocean which strengthens each other. The super position of the phenomenon of El Nino and the positive IOD has caused the growth of rain clouds in Indonesia to be far less than normal," he said.

According to him, the transition from the dry season to rain is generally closely related to the shift of the easterly wind/Australian monsoon which has turned into westerly winds/Asian monsoons from the direction of the Asian continent.

"Finally, it is hoped that if the wind comes from the Asian continent which brings water vapor from the Pacific Ocean around Asia, it is hoped that it will immediately provide rain clouds and bring rain seasons in the Indonesian Archipelago," he said.

From the results of the BMKG analysis, the east wind originating from Australia is predicted to remain active until November 2023, especially in southern Indonesia which is closest to Australia. Meanwhile, the westerly wind is predicted to come slower than normal.

Several areas close to the Asian continent have already received the rainy season, namely most of Aceh which is close to Asia, mostly North Sumatra, central West Sumatra, and a small part of the Riau Islands.

"Furthermore, the rainy season will occur in central and southern Sumatra and then almost sequentially followed in Kalimantan, Java, then gradually will dominate all parts of Indonesia in the period March to April 2024," he said.