July in Liberec is the warmest month of the year. In July, the weather in Liberec is typically warm. Average daily high temperature in July is about 21 degrees above zero. On average, Liberec has 22 rainy, 7 sunny, and 2 partly cloudy days in July. The rains are usually heavy. July as well as February, March, April, and May is considered the most uncomfortable time to visit Liberec.