Mawün-NRT: A web platform for near real-time evaluation of gridded precipitation products during extreme precipitation events in Chile

In an era characterized by increasing climate variability and the intensification of extreme weather events, the need for accurate and timely precipitation data has never been more critical. While several websites and applications offer weather forecasts that are improving every day, there is a critical gap in readily available post-event precipitation data. In this work we present Mawün-NRT (in Mapuzungun, “mawün” means "rain”), a free and publicly accessible web platform (https://mawunNRT.cr2.cl/) that provides a user-friendly visualisation of the spatio-temporal distribution of precipitation events for continental Chile in near real-time. Mawün-NRT was developed by the Water Resources Observatory of the Araucanía Region (Kimün-Ko, https://kimunko.ufro.cl) in collaboration with the Center for Climate and Resilience Research (CR2, https://www.cr2.cl), to supplement the existing web platform Mawün (https://mawun.cr2.cl/) which is focused on historical precipitation data. Three state-of-the-art precipitation products are included in this first version of Mawün-NRT: i) the near-real-time Multi-Source Weather (MSWX-NRT, 3-hourly, 0.1°), ii) PERSIANN Dynamic Infrared–Rain Rate (PDIR-Now, hourly and 0.04°) and iii) the Integrated Multi-satellitE Retrievals for GPM (IMERGv07 and IMERGv06, half-hourly, 0.1°) in both the Early and Late versions. In addition, hourly data from hundreds of rain gauges of different Chilean institutions (e.g. DGA, DMC, Agromet, CEAZA) are collected in near real-time by the Vismet web platform (https://www.vismet.cr2.cl/) and used in Mawün-NRT to compare the gridded precipitation estimates with the corresponding in situ values, as a soft measure of the uncertainty in the precipitation estimates. The near real-time capabilities of Mawün-NRT allows decision makers to evaluate which product provides better identification of the spatial area really affected by the precipitation event, fostering a timely decision-making and a proactive response to evolving weather conditions. A case study shows the monitoring of an extreme event that affected the south-central area of Chile in June of this year 2024, with devastating societal and economic impacts.