The present disclosure provides a method in a wireless device for initiating a handover from a source base station to a target base station. The method includes calculating a power offset indicative of a difference between a receiving power from the target base station and a receiving power from the source base station. A Time Division Duplex (TDD) configuration difference is obtained between a TDD configuration of the target base station and a TDD configuration of the source base station. A TDD offset is calculated based on the TDD configuration difference and an uplink-downlink traffic model of the wireless device. The handover is initiated based on a combination of the power offset and the TDD offset exceeding a threshold. The present disclosure also provides a wireless device, a method in a base station and a base station.