A raincloud visualization renders one hour of rainfall data as overlapping, semi-transparent ellipses on a map, with marker size and color scaled by precipitation intensity. The CartoCSS styles define six value-based classes, from deep blue for heavier rainfall to pale white for trace amounts, while zoom-dependent width rules amplify marker sizes at higher zoom levels. The visualization uses CartoDB's styling language with marker properties, zoom conditions, and composition operators to layer the raincloud effect.