An analysis of intense convectively-generated wind gusts in the Brazilian Amazon

Deep moist convection in the Amazon Basin has been a topic of active research for decades, but the documentation and understanding of convective storms that reach severe limits in that part of the world is still poor. Motivation does exist to further develop this field of study given that severe storms, mostly accompanied by extreme rainfall and/or damaging winds, can significantly impact not only forest structure, composition, and even carbon dynamics, but also local communities and cities. This study investigates intense convectively-induced winds gusts across the Brazilian Amazon using hourly WMO-compliant observations from the network of surface weather stations operated by Brazil's National Meteorological Institute (INMET) from 2000 to 2024. All convective gusts ≥15 m/s are sampled, with special focus on those surpassing 20 m/s, utilized as the regional threshold to characterize severe gusts. Compound occurrences of intense gusts and extreme precipitation are also analyzed, with their temporal variability, diurnal cycle, and seasonal patterns being examined. Hourly time-series of atmospheric pressure and air temperature around the time of the sampled gusts are assessed to identify features that typically accompany gust fronts, such as cold pools and mesohighs. The atmospheric environments prevailing during the intense and severe gusts are analyzed employing gridded data from ERA5 reanalysis. Preliminary results show that strong wind gusts in the Brazilian Amazon are mostly afternoon events, peaking around 20 UTC, and are most frequent during the dry-to-wet transition season, especially from September to October. The results also indicate that the magnitude of CAPE and DCAPE, and the height of the LCL, are key factors in characterizing environments more favorable for severe gusts.