Pan evaporation is affected by soil moisture levels. When the soil is dry, pan evaporation is higher than the potential evaporation calculated from weather data. A study found that pan evaporation is closely related to potential evaporation and soil moisture near a weather station. In drier conditions, pan evaporation can be significantly higher than potential evaporation. The researchers used multiple regression to show that soil moisture and potential evaporation can explain a large portion of the variance in pan evaporation measurements. For every 10% decrease in soil moisture, pan evaporation is estimated to increase by 0.2 mm per day.