Sensitivity analysis of microphysics and cumulus parameterization schemes: numerical simulation of cloudbursts over Uttarakhand using WRF modeling system

Cloudbursts are meteorological phenomena characterized by intense precipitation, resulting in the occurrence of flash floods and landslides within a spatial extent of around 20 km2. This study examines three cloudburst events that occurred on July 16, 17, and 19 of 2018 in three distinct sites within Uttarakhand. The Weather Research and Forecasting (WRF) model was employed to replicate three instances of cloudburst events, with a temporal resolution of 18 s, on a nested domain including resolutions of 9 km and 3 km. The model utilized spatial data from the National Centers for Environmental Prediction (NCEP) Final Analysis (FNL), which had a spatial resolution of 1° by 1°. A comparison was made between the Indian Monsoon Data Assimilation and Analysis (IMDAA) data. In all three examined situations, the simulations predict a precipitation amount of 100 mm and significant vertical velocity. There is a slight displacement observed in the maximum rainfall and vertical velocity between the two scenarios. The evaluation of each configuration was conducted using deterministic and categorical metrics, based on the rainfall observations from Integrated Multi-Satellite Retrievals for GPM (IMERG). Equitable Threat Score (ETS) and False Alarm Rate (FAR) skill score were computed for each timestep’s rainfall threshold of 5 cm. The results of the investigation demonstrated that the third configuration had the highest level of skills.