BENGALURU: Karnataka recorded a 32% rainfall deficit during the 2026 southwest monsoon season, marking the state’s highest shortfall since 1918, according to the India Meteorological Department (IMD). The deficit has raised concerns about water availability across the state, particularly if the upcoming northeast monsoon also delivers below-normal rainfall.
Between June 1 and September 30, Karnataka received 563.7 mm of rainfall against the normal 831.8 mm, according to IMD data. The 32% shortfall is the highest since 1918, when the region recorded a 47% rainfall deficit. Karnataka had recorded a 31% deficit in 2002 and an 18% deficit in 2023.
South Interior Karnataka records highest regional deficit
South Interior Karnataka, which comprises 17 districts, recorded the highest regional deficit at 36%. The region received 432.9 mm of rainfall against the normal 678.4 mm.
North Interior Karnataka recorded a 32% deficit, receiving 329.1 mm against the normal 480.8 mm. Coastal Karnataka, comprising three districts, recorded a 28% shortfall, with 2,226.7 mm of rainfall against the normal 3,093.9 mm.
The figures indicate that rainfall remained below seasonal averages across all three regions, although the extent of the deficit varied.
Ramanagara records the highest district-level deficit
Ramanagara recorded the highest rainfall deficit among Karnataka’s districts at 87%. The district received only 59.2 mm of rainfall against its normal 459.6 mm during the southwest monsoon period.
Belagavi was the only district to receive rainfall close to its normal level. It recorded 572 mm against the expected 573.3 mm.
The district-level figures highlight the uneven distribution of rainfall across Karnataka and the severity of the shortfall in some areas.
IMD flags concerns over northeast monsoon
The southwest monsoon officially withdrew from the country on October 14. Bengaluru IMD director N Puviyarasan said the monsoon had completely withdrawn from Karnataka over the preceding days, with no rainfall recorded in the state during that period.
Although rainfall in Karnataka during October was associated with the withdrawal phase of the southwest monsoon, the IMD classifies rainfall from October onwards under the northeast monsoon period.
The department has indicated the possibility of below-normal rainfall during the northeast monsoon as well. If rainfall remains deficient, water availability could become a greater concern in the coming months, particularly ahead of next summer.
El Niño cited among factors affecting rainfall
The IMD attributed below-normal southwest monsoon rainfall across India this year to the influence of El Niño and local weather conditions. The department warned that similar factors could also affect the northeast monsoon, potentially extending rainfall shortages across the country.
The extent of the impact will depend on rainfall during the coming months and conditions in individual districts. The latest figures underline the importance of monitoring reservoir levels, groundwater availability and water demand as Karnataka moves towards the next summer season.
With rainfall significantly below normal during the southwest monsoon, the performance of the northeast monsoon will be closely watched for its implications for agriculture, drinking-water supplies and overall water management in the state.