Climate During Visit ~ England

I will be taking my trip in June, so I researched the climate for that time of year and here is what I got. In June the average temperature high is about 20 degrees Celsius and the average low is about 13 degrees Celsius. Most people have heard that it rains a lot in England, so I had to check how much it is going to rain while I'm going to be there as I know it will. The average precipitation for the month of June is about 45 (mm).