This paper describes a two- dimensional lake breeze model With turbulent energy closure. The simulated results show that (1) the front of the lake breeze progresses inland faster in the late afternoon than at the fully developed stage;(2) the lake breeze and land breeze have larger extension offshore than inland. The acceleration of the front in the declining phase of the lake breeze is explained in terms of the decreased turbulent friction acting on the head of the lake breeze. The larger extension offshore, probably, is attributed to the smaller roughness of water surface and to the offshore synoptic wind.