The cranes arrive at Cao Hai Lake from late October and remain until late February or early March. Peak numbers are in December and January, when several hundred black-necked cranes can be seen simultaneously. This is also Weining's winter, with temperatures dropping to near zero at night at this altitude; pack accordingly.
The market days — on dates ending in 3, 6, or 9 in any month — are worth timing a visit around regardless of season. The spring rapeseed bloom across the plateau (March–April) and the clear autumn days (September–October) make those seasons pleasant even without the cranes, though the crane season is the primary reason to make the journey.