If you are designing an electronic device that goes into an outdoor enclosure how do you calculate the rise in temperature from solar loading? Say my safe operating ambient was 45C how do I understand what my safe operating temperature is in direct sunlight? I get that it has to do with surface area and color and I did find some formulas about determining Wattage for picking a cooling system. But nothing yet that helps me understand the temperature rise.
If the answer is test or simulate, is there a way to get an approximation?