Thunderstorms, heavy rains, strong winds and possible flooding are forecast for much of Indonesia through at least October 7. As of October 5, the Indonesian Agency for Meteorology, Climatology and Geophysics (BMKG) has issued orange (medium level on a three-level scale) flood warnings for Aceh and West Kalimantan provinces and the Jakarta metropolitan area for October 5-6 as well for West Java Province from October 5th to 7th. Yellow thunderstorm, strong wind and heavy rain warnings were issued across much of Indonesia from October 5 to 7. Authorities are likely to issue new warnings or update/remove existing advice if weather conditions change in the coming days.
Heavy rains late on October 4 caused flooding in parts of Greater Jakarta due to overflowing rivers. The floods have submerged a number of homes in parts of South, Central, West and East Jakarta, and at least six streets in the region have been engulfed by flood waters. However, authorities have reported that the floodwaters had largely subsided by the afternoon of October 5. The floods also affected around 1,250 households on October 4 and caused traffic congestion in South Tangerang and surrounding areas of Banten province. Heavy rains in Bone Bolango Regency, Gorontalo Province on October 2 triggered flash flooding in parts of North Bulango District. Around 375 homes were inundated by floodwaters and authorities evacuated at least 25 families from the affected area. Heavy rains in Sintang Regency, West Kalimantan province on October 2 caused the Serawai River to overflow. Subsequent flooding affected around 5,000 people and 1,000 homes and other buildings.
Continued heavy rains could trigger more flooding in low-lying communities near rivers, streams and streams. Coastal flooding is also possible at high tide. Urban flooding is also possible in built-up areas with easily overburdened stormwater drainage systems. Sites located downstream of large reservoirs or rivers may experience flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rains have saturated the ground. Power outages may occur throughout the affected area.
Floods and debris flows can make some bridges, rail networks or roads impassable and affect overland traffic in and around the affected areas. Waterlogging on road surfaces can also create hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes swamped by flood waters.
The disruptive weather may cause delays and cancellations at airports across the affected area. Authorities may temporarily halt port operations if strong winds create dangerous sea conditions and affect cargo and passenger ship traffic. Flooding could block regional rail lines; Delays and cancellations of freight and passenger trains are possible in areas with heavy rainfall and track closures.
Disruptions triggered by inclement weather and resulting hazards like flooding could linger long after conditions improve – it could take days for flood waters to recede and/or officials to clear debris. In the case of severe damage to the infrastructure, repair or reconstruction measures can lead to residual disruptions.
Before driving or directing broadcasts through areas where severe weather is forecast, find up-to-date information about weather and related disruptions, including road conditions. Accordingly, plan for possible delays in cargo delivery when routing shipments by truck through the affected area. Do not attempt to drive through flooded areas. Charge battery-powered devices during extended power outages.
Indonesian Agency for Meteorology, Climatology and Geophysics
Indonesian Agency for Meteorology, Climatology and Geophysics (Twitter)
Indonesian National Council for Disaster Management