Convective-Permitting Simulations of Extreme Weather and Climate Events in El Salavador with the Weather Research and Forecasting Model

El Salvador, located in northern Central America, is being increasingly subject to more extreme weather and climate in association with global climate change. In this study, the Weather Research and Forecasting (WRF) model is used to retrospectively simulate several extreme weather events at convective-permitting grid spacing using the ERA-Interim reanalysis as boundary forcing. These events caused major impacts to the country, according to the Salvadoran Ministry of Natural Resources and Environment. While convective-permitting modeling can potentially yield value added in representing extreme precipitation, the model simulations are extremely sensitive to the specification of the initial conditions. So achieving reasonably well performing deterministic simulations of extreme weather associated with localized mesoscale convective systems in this data poor region is quite challenging. When extreme events are more driven by large-scale features that are clearly realized within the driving reanalysis, the convective-permitting model results well match the observed spatial distribution of precipitation and amounts.

This research was conducted as part of a larger Fulbright NEXUS project to investigate climate change and its impacts in northern Central America. The research team is currently generating dynamically downscaled regional climate model data as part of the Coordinated Regional Downscaling Experiment (CORDEX), using WRF for a Central American domain with 25 km grid spacing. Some preliminary analyses of these data will also be summarized, as well as the progress toward generation and distribution of these data by multiple academic and research institutions across the Americas.