South of Valencia the weather warms up all year and the most popular expat areas start. It has a climate judged by the World Health Organisation to be the healthiest in the world, with warmth all year but tempered by Mediterranean breezes.
Costa Blanca North is greener, more mountainous and with smaller, quieter resorts and expat-friendly towns like Dénia and Jávea. Inland, the Jalón Valley is popular with overseas buyers. When you move south of Benidorm the Costa Blanca South is flatter and dryer.
While it has suffered from overdevelopment, it is also cheaper to buy in resorts such as Torrevieja and Orihuela Costa. The historic city of Alicante sits south of Benidorm and the Costa Blanca’s beautiful interior includes oddities such as the palm forest of Elche. Year-round golf is a speciality.
Source. THE AIPP/RICS/RDE Guide to buying a property in Spain