Southampton experiences oceanic climate. Its climate chart goes somewhat like this:
Spring (March to May): In this season, the temperature rises upto 17 degree Celsius. Though the weather is quite clear during the beginning of the season, soon rainfall comes at the end, especially in the month of May. That’s why there is less crowd in this season. Hence, this off-season can be considered to visit Southampton.
Summer (June to September): In this season, the day hours are quite warmer with temperature rising upto 22 degree Celsius. The night hours on the other hand become cooler with a drop in the temperature. Rainfall do happen in this season as well but at a minimal amount. Such climate makes it favorable for tourists to visit Southampton.
Autumn (October to November): This season is somewhat similar to Spring. With heavy rainfall and temperature around 15degree Celsius, it might be difficult to explore Southampton. If rainfall doesn’t bother you much, then you can definitely come in this season.
Winter (December to February): In winter, the temperature stays around 9 degree Celsius. Moreover, with occasional rainfall the weather becomes quite unbearable. Hence, if you are coming in this season you are definitely required to carry thick clothes to warm up yourself.
No matter whichever season you are coming to Southampton, make sure you are carrying an umbrella. Thus, the best season to visit Southampton is summer. With warm climate and less rainfall, it will become easier for tourists to explore the city.