NTB poised to experience nine-month drought

Mataram — Indonesia’s Meteorology, Climatology and Geophysics Agency (BMKG) forecasts that the 2026 dry season in West Nusa Tenggara (NTB) will last considerably longer than normal, with a duration spanning eight to nine months.

“We estimate the dominant duration will range between 25 to 27 ten-day periods, or approximately eight to nine months. The drought duration is quite extended, so it must be anticipated collectively,” said Nuga Putrantijo, head of the BMKG’s Climatology Station in NTB, during a press conference in Mataram on Monday.

Putrantijo stated that approximately 84 per cent of West Nusa Tenggara will enter the dry season period beginning in April 2026.

The peak of the dry season is expected to occur in August 2026 and is predicted to affect nearly the entire region, with a percentage ranging between 89 and 90 per cent.

Putrantijo explained that three main factors are driving the drier conditions and extended duration: the El Niño Southern Oscillation (ENSO) phenomenon, which is currently in a neutral phase and is forecast to persist until mid-2026. This factor, which is expected to emerge in the second half of 2026, could intensify drought conditions in West Nusa Tenggara.

“The second triggering factor is the Australian monsoon, dominated by easterly winds that transport dry air from Australia. We predict this monsoon to be active in the Indonesian region beginning in April 2026,” he said.

The third triggering factor involves sea surface temperature conditions, which also influence cloud formation and rainfall development across Indonesia, particularly in West Nusa Tenggara.

Putrantijo revealed that sea surface temperature anomalies around western and southern Indonesian waters are currently monitored as normal to cooler than average, thereby restricting the growth of rain clouds.

“These are the three main factors causing NTB to experience drier conditions and a more extended dry season duration,” he concluded.