Research

       Extreme precipitation events (EPEs), characterized by daily widespread heavy rainfall exceeding the 95th percentile across Central America, can have large impacts on agriculture, life, and property during the rainy season. EPEs during the Northern Hemisphere autumn, however, have been observed to be influenced by both tropical and extratropical originating phenomena such as easterly waves and cold surges, respectively. Given the limited research in this area, the novelty of this work is to apply a systematic approach for identifying and better understanding EPEs, and investigating their associated synoptic-scale variability using daily high-resolution observations and reanalysis products over Central America.

      The monthly frequency of daily EPEs over Central America during autumn is generally confined to enhanced terrain where upslope flow is highly favored. Based on the observed local synoptic features throughout autumn, EPEs are commonly associated with two dominant scenarios characterized by the presence of Central American gyres (CAGs) or cold surges prior to an EPE onset. CAG patterns favor EPE precipitation along the Pacific coastline of Central America as opposed to cold surges that favor heavy precipitation along the Caribbean coastline of Central America.