Given your list of beverages, it sounds to me you might be subconsciously self-medicating with caffeine :). Myself, I'm constantly drinking either black tea or diet coke, all day long. I only drink water as last resort. I've been like that since childhood. It only recently occurred to me that I'm always settling on drinking choices that supply me with stimulants, indicating a potential deficiency problem.

Drinking water excessively is often an indicator of illness eg diabetes. Other reasons exist. The "its a hot day" reason is better than most but cold non-sugar drinks are usually more refreshing.