This is the exact same way you would normally find the darkest parts of the image when you're removing any color casts from the shadow areas, but now, thanks to the Difference blend mode, these darkest areas represent the areas closest to midtone gray.
The warmest sea in Key Largo in March is 26Â°C/79Â°F, and the coldest sea temperature in March is 22Â°C/72Â°F. Average water temperature in Key Largo in March is 24Â°C/75Â°F. You can choose any other years:
Max: 28.4Â°C / 83.2Â°F. Avg: 26.1Â°C / 78.9Â°F. Min: 24.8Â°C / 76.6Â°F. These figures are calculated from several years of recorded data and are the maximum, minimum and average temperatures of all the recorded years. Average daily November sea temperatures. Monthly Key Largo water temperature chart.