A detailed assessment was carried out for extremely severe cyclonic storms (ESCSs) that developed over the Bay of Bengal during 1990–2020 using the India Meteorological Department (IMD) best-fit track data. During the past 30 years, the maximum intensity of land-falling ESCS has increased 26%, which is an average of about 8% increase per decade. Analysis signifies an increasing trend in the life cycle, duration of ESCS stage, and maximum wind speed of land-falling ESCSs. It is observed that the stage of land-falling ESCSs was very severe, and therefore, reliable forecast of land-falling ESCSs is very important having wide socioeconomic implications. Furthermore, a case study investigated the performance of Advanced Research of Weather Research and Forecasting (ARW) model for a 6-day forecast of ESCS Hudhud that developed over the Bay of Bengal during 2014. Performance evaluation was based on the impact of model domain size, vertical resolution, data assimilation, sea surface temperature (SST), gravity wave option (GWO), and air-sea flux parameterization schemes. Initial condition was improved through WRF 3D variational data assimilation (WRF-3DVAR) system. Thereafter, the simulated track, intensity, and intensification of the storm were validated against available IMD best-fit track datasets. Results from the ARW model indicate that the track and intensity of ESCS Hudhud were influenced by domain size, vertical resolution, data assimilation, SST, GWO, and air-sea flux schemes. Study deciphers that bigger domain, higher vertical resolution, data assimilation, and air-sea flux scheme with enthalpy coefficients provided a better forecast for ESCS Hudhud. The track errors on day 1 to day 4 was 61 km, 73 km, 85 km, and 96 km, respectively, and absolute error in terms of MSW was about 8 ms⁻¹, 7 ms⁻¹, 2 ms⁻¹, and 8 ms⁻¹ respectively at 9-km horizontal resolution.

使用印度气象局（IMD）的最佳拟合跟踪数据，对1990-2020年期间在孟加拉湾上空发生的极严重气旋风暴（ESCS）进行了详细评估。在过去的30年中，登陆陆地ESCS的最大强度增加了26％，平均每十年增加8％。分析表明，生命周期，ESCS阶段的持续时间以及降落的ESCS的最大风速都有增加的趋势。可以看到，陆上ESCS的阶段非常严峻，因此，可靠的陆上ESCS预报非常重要，具有广泛的社会经济意义。此外，一个案例研究了天气研究和预报高级研究（ARW）模型对ESCS Hudhud的6天预报的性能性能评估是基于2014年在孟加拉湾上空进行的。性能评估基于模型域大小，垂直分辨率，数据同化，海面温度（SST），重力波选择（GWO）和海气通量参数化方案的影响。通过WRF 3D变异数据同化（WRF-3DVAR）系统改善了初始条件。此后，针对可用的IMD最适合的轨道数据集验证了风暴的模拟轨道，强度和强度。ARW模型的结果表明，ESCS Hudhud的轨迹和强度受域大小，垂直分辨率，数据同化，SST，GWO和海气通量方案的影响。研究认为，更大的范围，更高的垂直分辨率，数据同化以及具有焓系数的海气通量方案为ESCS Hudhud提供了更好的预测。从第1天到第4天的跟踪误差分别为61 km，73 km，85 km和96 km，就MSW而言，绝对误差约为8 ms ^-1，7 ms ^-1，2 ms ^-1和水平分辨率为9 km时分别为8 ms ^-1。