3.2 million inhabitants make up the metropolitan region of Barcelona in the Western Mediterranean sea basin. Its climate conditions are hot and dry in the summer and mild and humid during winter.

Barcelona has recently been exposed to increasing temperatures and heat waves. These extreme weather conditions have affected the phenology of vector-borne diseases (the cyclic and seasonal natural phenomena of infections transmitted through bites of infected species). Citizens’ health is particularly vulnerable when facing extreme weather episodes.

In such a context, it is especially important to inform urban planning and housing retrofitting policies. The climate service developed in the context of I4C will focus on delivering tailored predictions and defining thresholds and formats to provide references for public health agencies to inform city intervention. Heat indicators (such as heat stress index, frequency of tropical night and drought indicators), socio-demographic data, and infrastructure quality information will be combined to