Monaco is known as a beautiful vacation stop because of it's enjoyable, calm climate. Located directly on the Mediterranean sea, Monaco has a mild mid-latitude climate, or a "mediterranean" climate (Cs). The constant breeze from the sea keeps the city-state from reaching scorching temperatures in it's summer months. 

Climate Data of Monaco 

Monaco has just two seasons, a summer and a winter. Summer in Monaco is typically warm and humid with no rain, while the winter is fairly mild and rainy. These seasons are what classifies Monaco as a "Cs" (Mediterranean) climate.

Another idea of year-round temperature and humidity 

If you are planning to vacation in Monaco, the summer months would be the best for lying on the beach and catching some sun. Although humidity can be higher in the summer, the winter months would be too cold for swimming. If you plan just to sight see and don't mind the cold sea breeze, the winter months are for you.