What's the current temperature in Hong Kong, Macau, Shenzhen and Haikou? What clothes are appropriate to wear?

There is little difference in temperature between Hong Kong, Macao and Shenzhen. It's about 17 to 223 degrees these days, and it will be colder next week. The lowest temperature may be 14, 15 degrees. The temperature in Haikou will be higher, about 20-27 degrees, but many Northeasters will find it colder when they go to the south, because the temperature difference between indoor and outdoor is not big, but there is heating in the north, so some northerners have to wear clothes even if the temperature is high. If it's safe, just bring a down jacket, a long-sleeved shirt and a thin coat, and wool is not needed. It's basically enough to wear a long-sleeved thin coat here.