In the area you have selected (San Diego) extreme heat hazard is classified as high based on modeled heat information currently available to this tool. This means that prolonged exposure to extreme heat, resulting in heat stress, is expected to occur at least once in the next five years. Project planning decisions, project design, and construction methods must take into account the level of extreme hazard. The following is a list of recommendations that could be followed in different phases of the project to help reduce the risk to your project. Please note that these recommendations are generic and not project-specific.
According to the most recent assessment report of the Intergovernmental panel on Climate Change (IPCC, 2013), continued emissions of greenhouse gases will cause further warming, and it is virtually certain that there will be more frequent hot temperature extremes over most land areas during the next fifty years. Warming will not be regionally uniform. In central and north-eastern continental USA, the temperature increase in the next fifty years will be slightly higher than the worldwide average. In Alaska, the temperature increase in the next fifty years will be much higher than the worldwide average. In western and south-eastern USA, the temperature increase in the next fifty years will be slightly lower than the worldwide average, but still significant. It would be prudent to design projects in this area to be robust to global warming in the long-term.
For further information the following resources could be consulted: