In a lake, which layer typically contains the warmest water during thermal stratification?

During thermal stratification in a lake, the surface layer is typically the warmest because it is directly exposed to solar radiation. This layer absorbs heat from the sun, causing the water temperature to rise. The warmer water at the surface is less dense than the cooler water below, which leads to stratification and the formation of distinct layers within the lake.

As you move deeper into the lake, the temperature generally decreases, leading to the formation of the middle layer, which is cooler than the surface layer. The deepest layer, often referred to as the hypolimnion, is the coldest area of the lake during stratification. The benthic layer, located at the bottom, also tends to be cold, as it is furthest from the warmth of the sun. Thus, the surface layer is always the warmest due to its direct sun exposure.