Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from South Carolina to Nantes as you normally would.
In terms of precipitation, rainfall in Nantes ranges from 2.0 - 3.5 inches per month. November is typically the wettest month, when rainfall can reach 3.5 in. April is typically the driest time to visit Nantes when rainfall is around 2.0 in.
If weather is an important factor for your trip to Nantes, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 66.2 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 41.0 F).