Heavy rainfall occurrences in northeast India

• DOI: 10.1002/joc.3526
• Publication Date: 2012-05-30T10:13:23Z
• Authors: Rahul Mahanta; Debojit Sarma; Amit Choudhury
• Keywords: 13. Climate action; 15. Life on land; 01 natural sciences; 0105 earth and related environmental sciences

Abstract In operational meteorology, forecasting heavy rainfall (HRF) events has been a long‐standing challenge in India. This is especially true certain regions where the physical geography lends itself to creation of such HRF events. Northeast India (NEI) one region within Asian monsoon zone, which receive very during pre‐monsoon and summer season summer–autumn transition month October. These cause flooding, damage crops bring life standstill. present work, characteristics NEI are studied. The seasonal spatial variations occurrences analysed using 31 year (1971–2001) daily data from 15 stations. Using obtained Indian Meteorological Department, most favorable locations were found for stations between 27.5°N 28.1°N. time occurrence these 10 June 5 August. July records largest number followed by aggregate extreme rain over significant decreasing trend region. Before sets in, there considerable thunderstorm (TS) activity this April May that also While many occur associated with Nor'westers (tornadoes), some severe TSs may season. So, we climatology TS days. Also annual variation convective available potential energy (CAPE) inhibition (CINE) at Guwahati as index thermal instability. Between 1973 2001, CAPE shows whereas CINE an increasing seems reasonable due events' trend. Copyright © 2012 Royal Society