Evapotranspiration (referred to as ET) is the amount of water lost from the soil or leaf surface by evaporation and water passing through the plants by transpiration. Evapotranspiration is typically expressed in inches of water per hour or day. Evapotranspiration losses can be estimated using meteorological data measured with a weather station.

Weather conditions change, affecting the amount of evaporation and transpiration. ET and rain shown in Las Vegas 2003 demonstrate the changing need for water. By using real-time weather information from your area Weather Reach can provide effective water management.