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A significant change in the precipitation pattern over India has been reported in previous studies. This change includes an increase in heavy precipitation and a decrease in light and/or moderate precipitation. This study examines the possible link between these changes and regional climate conditions, using regional surface temperature and Vertically Integrated Moisture Transport (VIMT) records. It is reported that precipitation extremes during the southwest (SW) monsoon season show coherent variability with surface temperature over India. The precipitation spectrum shows significant changes from cold to warm years, with increases in heavy precipitation and decreases in light and/or moderate precipitation. The study reveals a decreasing trend in VIMT over the Bay of Bengal, which is consistent with decreases in the number of monsoon depressions over the region. It is observed that an increase in VIMT over the Arabian Sea shows coherent variation with precipitation extremes over India. The results reported in this article are crucial when considering the increase in drought and flood events in a changing climate.

South-west monsoon of 2019 advanced towards northern parts of India during the first week of July. Heavy-to-very-heavy rainfall events during July 05-16 resulted in severe flooding over Bihar and Assam and caused huge damage in the form of life and property. More than 90 lakhs people have been affected, and about 100 causalities have been reported in Bihar and Assam due to severe flooding. Results presented in this short communication highlight the importance of space-borne near real-time monitoring of flood events. It is reported that few districts of Assam and Bihar received cumulative rainfall in excess of 1200 mm from multiple heavy rainy events during July 05-16, 2019. Heaviest rainfall events were reported on July 06, 11 and 13. Few districts of Assam and Bihar experienced daily rainfall in excess of 300 to 400 mm during these heavy rainy days with peak hourly rainfall exceeding 50 mm at few synoptic hours. Discharge from Kosi and Brahmaputra rivers combined with heavy cumulative rainfall from multiple rainy episodes during July 05-16 resulted in severe flooding over Assam and Bihar causing losses to life and property.

Kerala, a southern state of India, experienced a severe flooding due to multi-day extreme rain events during July and August months of 2018. This disaster was one of the worst floods to hit the state and resulted in heavy losses of lives and property. Natural Disaster Management Authority of India reported that 483 people lost their lives and more than 50 lakhs population were affected severely. This short communication focuses on examining this flood event using satellite remote sensing. It is reported that Kerala received an excess of about 56% rainfall during July and August from multi-day extreme rainfall episodes. Few regions of Kerala received the rainfall in the range of 270-300 mm on August 14 and 15. Hourly rainfall events in the excess of 25 mm have also been reported during heavy rainy days. The present study reports that multi-day heavy rainy events during July and August brought an accumulated rainfall of about 1600 mm, which resulted in extreme flooding over Kerala.

online only Multiple days with periods of torrential rain in Rajasthan (an arid state of India) during July and August 2019 resulted in extreme flooding in several districts, causing heavy damage to lives and property. The research described in this short communication examines this flood event using observations from satellite data. Baran, Bhilwara, Pali, Jhalawar, Jodhpur, Kota, Udaipur, Dungarpur and Banswara districts of Rajasthan were severely affected. Banswara, Dungarpur, Pali, Bhilwara, Kota and Jhalawar districts of Rajasthan received a cumulative rainfall total in excess of 1000mm for July and August 2019. Peak precipitation was in excess of 300mm day−1 on 15–16 August 2019 over some of these districts. Pali district recorded maximum rainfall rates in excess of 50mmh−1 on 15th and 16th August at 0630 utc and 0500 utc, respectively. Over a few of the regions of these districts, rainfall totals were in excess of 150% of the normal during July–August 2019, resulting in flash flooding. We also report that severe flood events are on the rise in recent decades over Rajasthan. Therefore, a proper flood management strategy is required to combat the risk of future flood disasters.