Check the weather along your planned route!

Before packing for a trip I check weather along the route. I go to www.google.com , for e g Khartoum, in Africa, I search for: Khartoum weather average BBC. For this city you find that the maximum average temperature reaches 42 C, 108 F. The highest recorded temperature is 48 C, 118 F, and that "Discomfort from heat and humidity" is "Extreme" in September.

If you turn up there and then in your temperate climate outfit your outdoor action time in some comfort will be extremely short - about ten minutes. In my dress and with my gear I can be comparatively comfortable much longer, especially if there is a bit of wind.