I just fished in this shirt yesterday. The high was 92 and I stayed surpisingly cool. Tip: to get cool quick, soak the shirt in water and put it back on. It appears the shirt needs to be wet, (water or sweat) to work. Another tip, keep an extra ballcap in the cooler and rotate your caps as they dry out. A wet cap feels great on a hot day. The cool cap and this new shirt are a great combination.