I retired from USPS as a mail carrier after 33 years a few years ago... Yep, outside in all weather. Not only did I learn what works in the cold, but also what works in the heat. Silly me would even commute to work by bike 10.5 miles each way in the peak of summer heat and humidity. I just wore my uniform shorts and a t-shirt that I'd soak with water before I set out for home. Evaporative cooling works!