http://knows.jongo.com/res/article/2009  
Yearly Climate Info-Kaifeng
Detailed information about the Average, Maximum and Minimum Temperatures and the rainfall in Kaifeng （开封）
Average Data
Jan
Feb
Mar
Apr
May
June
July
Aug
Sep
Oct
Nov
Dec
Rain (in)
0.3
0.4
1.0
1.7
2.1
2.4
5.9
4.9
2.9
1.6
1.0
0.4
Rain (mm)
7.5
12.5
27.5
42.5
52.5
62.5
152.5
127.5
72.5
42.5
27.5
12.5