Indonesia Weather Warning Update June 23-25, 2026: BMKG on Alert for Heavy Rain in 3 Provinces
Indonesia weather warning update for June 23-25, 2026: BMKG warns of heavy rain in three provinces and urges residents to stay alert.
JAKARTA — Indonesia Weather Warning Update June 23-25, 2026: BMKG on Alert for Heavy Rain in 3 Provinces, with North Sumatra, the Bangka Belitung Islands and West Java facing the highest risk from Monday through Wednesday. The state weather agency said more than 20 other provinces also face rain that could slow travel, disrupt work and raise the risk of local flooding.
The warning matters fast for people on the move. Roads near hillsides, riverbanks and low-lying neighborhoods could become dangerous in a matter of hours, while commuters and freight operators may need to plan around afternoon downpours.
Three provinces under Alert status
BMKG’s Alert status means the chance of heavy to very heavy rain is high enough to raise the threat of hydrometeorological disasters. For this period, the agency placed North Sumatra, Bangka Belitung Islands and West Java in that category.
| Region | Status | Potential |
|---|---|---|
| North Sumatra | Alert | Heavy to very heavy rain |
| Bangka Belitung Islands | Alert | Heavy to very heavy rain |
| West Java | Alert | Heavy to very heavy rain |
BMKG did not issue a broad strong-wind warning for this period, but it warned that heavy rain can still arrive with lightning and sudden gusts in localized areas. That combination is enough to snap tree branches, reduce visibility and make roads slick in minutes.
More than 20 provinces still face rain
Outside the three Alert provinces, BMKG said moderate to heavy rain could affect a wide stretch of the archipelago. The list includes Aceh, West Sumatra, Riau, the Riau Islands, Jambi, South Sumatra and Bengkulu.
Central Java, East Java, Banten and West Nusa Tenggara are also in the forecast. So are East Kalimantan, North Kalimantan, Central Sulawesi, West Sulawesi, South Sulawesi, Southeast Sulawesi, North Maluku, Maluku, and all Papua provinces from Southwest Papua to South Papua.
The pattern shows Indonesia is not entering the dry season in the same way everywhere. Some regions are drying out, but large parts of the country still have enough moisture in the atmosphere to produce meaningful rain, especially later in the day.
Why the warning hits daily life
For families, the warning affects far more than weekend plans. A heavy shower can flood market roads, delay school pickups and cut off short routes that people rely on every day. In rural areas, landslide-prone slopes and river crossings are the bigger fear.
That is why BMKG is urging people in the three Alert provinces to stay away from flood channels, unstable hillsides and riverbanks when rain starts to build. Residents were also told to prepare emergency supplies if they live in an area that has flooded before.
BMKG said weather updates are available every six hours through its InfoBMKG app, a tool many Indonesians use before traveling by road, sea or air. The agency’s advice is especially relevant for farmers, fishers and transport workers whose schedules often depend on short windows of dry weather.
Hot mornings, wet afternoons
BMKG said the next three days should follow a familiar pattern across much of Indonesia: hot and clear from morning to midday, then clouds, thunderstorms and rain later in the day. That means exposure to strong ultraviolet light before the rain arrives.
Data from Palembang, which BMKG used as a South Sumatra reference, shows temperatures of 32-33°C with UV Index readings of 8, or Very High, on June 23 and 11, or Extreme, on June 25. Humidity is expected to run between 62 and 72 percent, with southeast winds at 8-14 kph.
The chance of rain in Palembang on June 25 is listed at 10 percent, a relatively low figure. But BMKG stressed that conditions differ by province, and the three Alert areas face a much higher threat than that reference forecast suggests.
People heading outdoors were advised to use sunscreen with a high SPF, wear hats and cover exposed skin, especially between 10 a.m. and 2 p.m. WIB. That is the window when UV exposure can be strongest, even before clouds build.
Forecast extends to June 29
BMKG also issued an outlook for June 26-29, 2026. Moderate rain could still hit Aceh, North Sumatra, West Sumatra, the Riau Islands, Jambi, South Sumatra, Bangka Belitung, Bengkulu, West Java, Central Java, East Java, West Nusa Tenggara, Kalimantan, Sulawesi, Maluku and Papua.
The Alert zone changes in that longer forecast. Papua Highlands moves into Alert status for heavy to very heavy rain, while the current Alert provinces — North Sumatra, Bangka Belitung Islands and West Java — still need close monitoring because atmospheric conditions can shift within 24 hours.
BMKG said residents should not rely on one weather source alone. The agency remains Indonesia’s official reference for weather warnings, and its six-hour updates are meant to help people make faster decisions before they travel or work outdoors.
"Check the forecast before leaving home," a BMKG official said in the advisory, adding that the warning is especially important for communities in flood-prone and landslide-prone areas."}
