A disastrous cloudburst and associated floods in Kerala during the 2019 monsoon season raise the hypothesis that rainfall over the west coast of India, much of which is stratiform, may be trending towards being more convective. As a first exploration, we sought statistically significant differences in monthly ERA-5 reanalysis data for the monsoon season between two epochs, 1980–1999 and 2000–2019. Results suggest a more convective (deeper, ice-rich) cloud population in recent decades, with patterns illustrated in ERA-5 spatial maps. Deepening of convection, above and beyond its trend in amount, is also indicated by the steeper regression slope of outgoing longwave radiation trends against precipitation than that exhibited in interannual variability. Our reanalysis results are strengthened by related trends manifested in more direct observations from satellite and gauge-based rainfall and a CAPE index from balloon soundings data.

2019 年季风季节喀拉拉邦发生的一场灾难性暴雨和相关洪水引发了这样一种假设，即印度西海岸的降雨（其中大部分是层状的）可能趋向于更多的对流。作为第一次探索，我们在 1980-1999 年和 2000-2019 年两个时期之间的季风季节每月 ERA-5 再分析数据中寻求统计学上的显着差异。结果表明，近几十年来出现了更多对流（更深、富含冰）的云群，其模式在 ERA-5 空间图中得到了说明。与年际变率相比，出射长波辐射趋势对降水的回归斜率更陡峭，这也表明对流的加深超出其数量趋势。