Science & Tech · Science & Environment · 2 hrs ago
Indonesia’s Rainy Season Delayed, With Peak Expected From December to February
Indonesia’s weather agency says the rainy season will arrive late because very strong El Niño conditions have prolonged dry weather.
The agency forecasts the season will begin between November and December 2026.
The rainy season is expected to peak from December through February, spanning the end of 2026 and start of 2027.
Rainfall is forecast to be around the 30-year average, but the rainy period will be shorter than usual.
The delay affects 529 seasonal zones, or 61.08% of Indonesia’s land area, according to the agency.
A shorter season followed by a concentrated peak raises the need to prepare for flooding and landslides.
The agency urges residents to clear drains and conserve water as conditions require.
Indonesia’s rainy season is expected to arrive later than usual, with the start forecast from November to December 2026.
The peak is expected in December 2026 and January and February 2027.
The weather agency BMKG attributes the delay to a very strong El Niño, alongside the Indian Ocean Dipole.
BMKG says rainfall is expected to be around the 30-year climatological average, but over a shorter period.
It has warned people to prepare for possible floods and landslides.
- Who
- Indonesia’s Meteorology, Climatology, and Geophysical Agency (BMKG), led by Teuku Faisal Fathani, issued the forecast.
- What
- The rainy season is expected to start later than usual, with its peak from December to February.
- When
- The start is forecast for November to December 2026; the peak is forecast for December 2026 to February 2027.
- Where
- Indonesia.
- Why
- BMKG says a very strong El Niño and the Indian Ocean Dipole have worsened and prolonged dry conditions.
This story does not have two clearly opposing sides.
BMKG said El Niño and the Indian Ocean Dipole were worsening and prolonging dry conditions, delaying the rainy season.
Faisal said the rainy season was arriving later and warned of extreme rain toward the end and start of the year.
BMKG forecast the start of the rainy season across Indonesia.
BMKG forecast the peak of the rainy season.
- Delayed start
- November–December 2026
- Expected peak
- December 2026–February 2027
- Affected seasonal zones
- 529 zones, or 61.08% of Indonesia’s land area
- Longest recorded dry spell
- 161 days in DI Yogyakarta, as of October 10, 2026
- Rainfall outlook
- Around the 30-year climatological average, over a shorter period
What people are saying
the peak of the rainy season will be in three months: December, January, and February
the rainy season is coming in somewhat later
the rainfall will be the same as the average over the last 30 years, but the period will be shorter