Guilin is located in the northeast of the Guangxi Zhuang Autonomous Region on the west bank of the Li River. As it lies in the tropical monsoon zone it features a warm & damp climate.
There is a clear division between the four seasons in Guilin:
Spring is generally warm and rainy. The best travel time is between the end of April and June.
Summer is hot and humid but with plenty of sunshine. You better take plenty of water with you to avoid dehydration.
Autumn is the second big travel season as the weather cools and the flora prepares for Winter. It is harvest seasons for the rice fields (especially beautiful on the terraced fields in Longsheng) and in the old villages around Guilin the Ginko trees turn into every shade of yellow. Autumn is also the best time to go hiking in Guilin
Winter is cold mostly pretty damp. If you want to travel now you should consider taking an extra layer of long underwear with you. While the temperature seldom drops below freezing, the moist air will make your bones chilly.
If you are an expat, visit Guilin Expat for Guilin related Information.