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1. Introduction
The intra-American region encompasses Northern South America, Central America, Gulf of Mexico, the Caribbean region, and the Western Atlantic [1–3], where a complex interaction among synoptic atmospheric/oceanic patterns drives the rainfall activity in the region [4–7] (see Figure 1(a)).
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In tropical regions, the Sea Surface Temperature (SST) is one of the variables that drive rainfall, with a weak impact when SST is less than 26°C and a stronger effect when SST is between 26°C and 29.5°C. The relationship between SST and rainfall is not linear, so precipitation tends to decrease when SST is greater than 29.5°C [8]. Consequently, SST modulates the intra-Americas region (IAR) rainfall development from May to July, while in the next months the vertical wind shear (VWS) impacts the thermal vertical convection and cyclogenesis activity [5, 9, 10]. An additional variable in the IAR is the Bermuda-Azores high-pressure system (one pole of the North Atlantic Oscillation Index, NAO) which interacts with the Caribbean low-level jet, causing a downward dry air, hindering precipitation, and warming the surface [4, 11, 12]. A direct consequence of the high-pressure system oscillation is the development of stronger/weaker easterly winds causing cooler/warmer SST leading to a drier/wetter region [4, 13, 14]. This relationship is known as the wind-evaporation-SST feedback pointing out a direct relationship among wind speed, evaporation, and sea level pressure (SLP) [15]. Furthermore, a deep subsidence from Central America to the Caribbean region could play an additional role in the IAR rainfall activity [4, 16]. Moreover, Saharan dust episodes from June to August are likely to generate a rainfall deficit due to aerosol interaction with cloud condensation nuclei and dry air coming from the northwest African desert [17]. These complex relationships lead to a bimodal rainfall pattern in the IAR during the rainy season [4, 5, 18–21]. This rainy season is divided into the Early Rainfall Season (ERS) defined from April to July (which contains the first rainfall peak) and the Late Rainfall Season (LRS) from August to November, holding the second rainfall peak. In addition, a dry season...