Bengaluru, Karnataka – May 20, 2025: Intense pre-monsoon rains lashed Bengaluru over the weekend, triggering widespread urban flooding. The India Meteorological Department (IMD) reported very heavy rainfall across coastal and interior Karnataka and issued a yellow alert for Bengaluru and several neighboring districts. Overnight downpours on May 18–19 led to severe waterlogging in low-lying neighborhoods. Local authorities say teams have been clearing drains, removing debris and fallen trees to restore normalcy. (Meteorological data and forecasts below are from IMD and state disaster agencies.)

Rainfall and IMD Warnings

The IMD's May 18 press release warned of heavy to very heavy rainfall over Karnataka during May 18–24. In particular, its impact-based bulletin of May 19 forecast isolated extremely heavy rains in coastal and interior Karnataka and Konkan & Goa for May 20–21. The all-India weather warning on May 19 explicitly called for "Very Heavy Rainfall...at isolated places over...Coastal Karnataka, Interior Karnataka" that day.

A follow-on bulletin for May 20–22 likewise highlighted heavy to very heavy rain continuing over South Interior Karnataka. According to IMD data, parts of Bengaluru Urban district recorded well over 100 mm of rain in 24 hours by the morning of May 19. The steady downpours prompted IMD to issue a yellow rain alert for Bengaluru through May 22 and orange alerts for neighbouring coastal and Malnad districts.

Flooding Impact on Roads, Traffic and Homes

Persistent heavy rain led to localized flooding of roads and waterlogging in low-lying areas, with underpasses closed off in Bengaluru's suburbs. Large stretches of the Outer Ring Road and several arterial routes became impassable. Traffic reports and official advisories warned of major traffic disruptions; officials noted that waterlogged streets caused long congestion and detours.

In hardest-hit areas such as Sai Layout and Horamavu, floodwaters entered ground floors, submerging parked vehicles and damaging homes. Overnight, many residents in these low-lying neighbourhoods shifted to temporary shelters. Civilians are reporting floating debris and submerged potholes on residential streets. BBMP engineers have been pumping out water and clearing silt from drains; municipal teams also removed dozens of uprooted trees blocking lanes. (IMD forecasters had cautioned that urban areas could see closure of underpasses and traffic jams due to rain, and minor damage to infrastructure.)

Other Districts under Alert

Beyond Bengaluru, the IMD and Karnataka State Natural Disaster Monitoring Centre (KSNDMC) forecast continued heavy rains across the state. Coastal Uttara Kannada and Dakshina Kannada, Udupi and Chikkamagaluru in the Malnad region were under an orange alert for 100–150 mm rains. South Interior Karnataka districts (including Bengaluru Urban/Rural, Tumakuru, Ramanagara) faced yellow warnings through the week; heavy showers were expected to extend eastward into Ballari and Mysuru districts.

Northern Malnad and Maidan districts (Belagavi, Haveri, Dharwad) also saw yellow alerts as troughs lingered over the state. (KSNDMC bulletins note that rainfall 18–20 May was unusually heavy for May across Karnataka.) In summary, most of coastal, Malnad and central Karnataka was on flood watch: "very heavy rainfall...over South Interior Karnataka during 18th–20th May", with lighter rains drifting elsewhere.

Public Advisories and Precautions

Officials have urged residents to stay alert and avoid unnecessary travel. The IMD advised commuters to "check for traffic congestion before leaving", to follow any traffic advisories, and to avoid areas prone to waterlogging. The agency also warned people to refrain from entering flooded underpasses and to be ready to move to higher ground if needed.

Citizens were reminded to stay indoors if possible during heavy rain and to keep children and the elderly away from flooded areas. In addition, advisories cautioned against the dangers of sitting water, urging people to avoid contact with moving floodwaters and electrical lines. The Karnataka State Police and BBMP have set up control rooms and are monitoring rain levels; public helplines and official social-media channels will broadcast updates on road closures.

Official Imagery and Maps

The Karnataka government and IMD provide public weather maps and forecasts online. For example, IMD's district-wise rainfall distribution maps (updated daily) and regional weather charts are available on the agency's portals. Satellite-based precipitation products can be viewed via ISRO's MOSDAC/Bhuvan portals. (See Karnataka SNMC bulletins and BBMP Twitter feeds for geotagged pictures of flooding and drainage-clearing operations.)