Subseasonal-to-seasonal extreme rainfall scenarios for the Caribbean Basin

A method for identifying subseasonal-to-seasonal (s2s) scenarios of extreme rainfall for the Dec-Feb and Apr-Jun seasons in the Caribbean Basin is discussed. The approach involves an objective classification of atmospheric circulation patterns using velocity potential anomalies at 850 mb. These circulation regimes, or weather types, characterize different precipitation patterns in the Caribbean, and their seasonal frequency of occurrence modulates the spatial and temporal distribution of precipitation through the season. The weather types are also shown to be linked to particular sea surface temperature anomalies observed in both the Pacific and Atlantic oceans in the months preceding the seasons under analysis, suggesting potential predictability. The role of other potential predictors, and their cross-timescale interactions, is also analyzed.