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Abstract

This study presents the first climatological analysis of heat waves in Cuba from 1951 to 2023. Here we define a heat wave as a period of at least three consecutive days in which the daily maximum and minimum temperatures exceed their respective calendar-day 99th percentile. Our analysis detected a total number of 393 heat waves (∼ 5.4 events per year) over the three regions (western, central and eastern) during the study period, distributed ∼ 3.1 per year during the dry season (from November to April) and ∼ 2.3 per year during the rainy season (from May to October). The highest frequency was recorded in the western region of Cuba, albeit the eastern region is the hottest one. The analysis of the life cycle of the heat waves revealed that they are relatively short-lived, with a mean duration of ∼ 4.9 and ∼ 5.3 days in the dry and rainy seasons, respectively. Furthermore, we found a statistically significant (p < 0.05) upward trend in the frequency, intensity, spatial extent and annual number of days under such hot extremes. The Lagrangian heat analysis revealed a predominantly local origin of the sensible heating, followed by heat advected from upwind sources throughout the easterly winds. An assessment of the main physical mechanisms associated with these heat waves revealed that, in general, these hot extremes were exacerbated by the soil moisture deficit, high-pressure conditions and associated clear skies and increased solar radiation. Based on the Heat Wave Magnitude Index, we also presented the top 10 Cuban heat waves, which mainly occurred in the last decade, confirming the upward trend in the intensity of these extreme events. Overall, this study provides insights into the heat waves in Cuba and contributes to the development of physically plausible storylines to help decision-makers in implementing mitigation and adaptation strategies in the context of global warming.