It's not very suitable to go in winter.

Because it snows in Shangri-La in winter and there are no flowers.

Shangri-La is also cold in winter, with several degrees below zero.

Lugu Lake is ok. The temperature is similar to that in Lijiang.

You can spend two days in Dali, visit Erhai Cangshan and then visit the ancient city of Dali.

Dali: Cangshan Mountain, Erhai Lake, Santasi, Xizhou Residence, Jizu Mountain, and Foreigners Street in Dali Ancient City. Accommodation is recommended in Gucheng Inn, where you can eat live fish that can be boiled alive, ham fried with tree head vegetables, Dali seaweed soup, pickled snails, Weishan Barou bait, Dali hot and sour fish, chicken bean jelly, Dali stewed plum, Dali frozen white bean curd fish

and then go to Lijiang from Dali. It takes about two and a half hours by car

Then you go to Lugu Lake from Lijiang, and take a bus from Lijiang Bus Terminal, and it takes about five hours

Shangri-La, you can decide whether to go to Lijiang.

Lijiang: Dayan Ancient Town, Mufu, Yulong Snow Mountain, Heilongtan Park, Shuhe Ancient Town, Yushui Village, Qianguishan Mountain, Tiger Leaping Gorge, Shangri-La and Lugu Lake. Old Town of Lijiang Inn is recommended for accommodation, Lijiang Jinsha Tourism, Lijiang Special Chicken Hot Pot, Lijiang Baba, yellow bean, Buttered Tea, Fried Potato, Rice Enema, Yak Yogurt, Potato Chicken and Native Rice Noodles are recommended for tourism.

The ultraviolet rays here are relatively strong, the climate is relatively dry, and the temperature difference between morning and evening is relatively large. These should be noted. If you don't have enough rest, going to some scenic spots will easily cause dizziness and altitude sickness. If you want to go to the scenic spot by yourself, you need to pay attention to this to avoid being cheated by the locals. Don't buy things at the scenic spots at will, because the things sold at the scenic spots are similar, but they are very expensive

I hope the answer will help you.