Evaporation

[cleancloths]

Has it been windy? I would likely attribute the higher evaporation to windage than temperature.

[mas985]

Evaporation depends on humidity, temperature and wind speed. A warm pool with a cool low humidity night is one of the best conditions for evaporation and you will tend to lose more water at night than during the day.

Useful site:

http://www.grow.arizona.edu/Grow--Gr...ResourceId=208