July in Dundalk is the rainiest and the warmest month of the year. In July, the weather in Dundalk is typically warm. Average daily high temperature in July is about 16 degrees above zero. On average, Dundalk has 27 rainy, 3 sunny, and 1 cloudy day in July. The rains are usually heavy. July as well as January, February, March, and April is considered the most uncomfortable time to visit Dundalk.