The Solar Sync Sensor is an advanced weather sensor that calculates evapotranspiration (ET) and adjusts Hunter controllers daily based on onsite weather conditions. Solar Sync measures sunlight and temperature, and uses ET to determine the correct seasonal adjustment percentage value to send to the controller. The controller then uses its programmed run time and adjusts to Solar Sync’s seasonal adjustment value to modify the actual irrigation run time for that day. It has a rain sensor and a solar radiation/temperature sensor built in to gather weather-based data and adjust the irrigation schedule. The rain sensor shuts off an irrigation cycle as soon as rain begins to fall.