I cannot provide a definitive answer to this question without more information about the specific climate conditions in question. However, in general, it is recommended to use limestone with a low thermal conductivity for exterior applications in sunny climates to prevent it from heating up and becoming uncomfortable to the touch. Portugals Rising Sun Limestone is known for its durability and resistance to weathering, making it a good choice for exterior use. It is always advisable to consult with a professional before making a final decision on the use of any material in exterior applications.