India: Disruptions due to flooding ongoing across parts of Andhra Pradesh, Karnataka, Kerala, and Tamil Nadu states as of early Oct. 16

Disruptions due to flooding are ongoing across parts of Andhra Pradesh, Karnataka, Kerala, and Tamil Nadu states as of early Oct. 16. Heavy rainfall in recent days amid the current monsoon season has triggered widespread flooding.

Residents of AGS colony in Velacherry in Chennai City, Tamil Nadu State, were evacuated from their homes due to flooding. Bus services across the state were canceled or diverted on Oct. 15. Several trains were also canceled, including eight express trains at Chennai Central Station, due to flooding between Basin Bridge and Vyasarpadi stations. At least 12 flights were canceled, and around 23 flights were delayed at Chennai International Airport (MAA). Authorities have advised companies to function with the least number of employees or advise employees to work from home through at least Oct. 18.

Authorities in Karnataka State have advised companies in Bengaluru City to allow employees to work from home on Oct. 16 as the heavy rain will likely cause traffic congestion across the city and hamper the commute to work. The Hebbal Flyover and Okkalipura Underpass already saw major slowdowns. All schools and colleges in Bengaluru City in Karnataka State, as well as Chennai, Chengalpattu, Kancheepuram, and Tiruvallur districts in Tamil Nadu State, are closed Oct. 16, while some schools in parts of Andhra Pradesh State are closed through Oct. 18.

Further adverse weather is forecast across the region over the coming days, and additional downpours will likely exacerbate the flood situation. The India Meteorological Department has issued red heavy thunderstorm warnings (the highest level on a three-tier scale) across Andhra Pradesh and Tamil Nadu state Oct. 16 and orange warnings across the rest of southern India Oct. 16-17. Yellow thunderstorm warnings are forecast to persist over Tamil Nadu State Oct. 18-19. Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.

Further sustained heavy rainfall could trigger additional flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where the soil has become saturated by heavy rainfall.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.

Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters. Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas that see heavy rainfall and potential track inundation. Severe weather will also probably trigger flight delays and cancellations at airports in the region.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.

Flooding could heighten the threat of disease outbreaks. Backflow from drains mixed with floodwaters can become trapped in open areas when inundations recede. These stagnant pools often become a breeding ground for mosquitoes and bacteria, increasing the incidence of insect- and water-borne diseases. Exposure to contaminated water from inundated industrial sites, sewer systems, and septic tanks also poses a significant health threat.