17°F (-10°C) ass-rippingly cold

I took a nice, long, 26K-step walk Friday night, breaking away from my usual path to go east along the Han River—something I've done a few times over the past week as I continue to contemplate walking to Paldang Dam and beyond. Things were fine until I was at the river itself: a constant wind was blowing, bringing a wind chill with it. My phone was telling me the temperature was 17 degrees Fahrenheit, or -10 Celsius—about 23 degrees Fahrenheit colder than it is in a standard refrigerator. I was fairly well bundled up, except for my legs, because I was wearing my standard, paper-thin hiking pants—the pants I wear almost every day (I do wash them twice a week). But the main problem was how the relentless wind was chilling my forehead, right through my knit winter hat. I was in actual pain because of the cold; I don't know how to calculate wind chill, but the bones of my skull were telling me that the time had come to turn around and go back to my place. Eventually, my return path took me inland, away from the river and the wind, which was a relief. I'm now left to wonder whether I need to buy a hoodie or a second hat in order better to protect my forehead from the harsh elements.

Here's a pic of me with my face mask pulled partway down:

I survived the walk, and I gained a great deal of practical knowledge from pushing myself that way. I now know that walks in this sort of cold weather are still feasible, but they'd be made a bit more comfortable with better headgear and, possibly, an extra layer of clothing to cover my legs. I can solve the latter problem by going home and pulling on my sweatpants, but the headgear problem will probably require me to purchase something.