Anyone who has done fall or winter races knows one simple fact: people do NOT know how to dress. I'm not talking about fashion. I'm talking about function. Clothing that keeps you warm and dry, without keeping you TOO warm and making you sweat through your gloves. Overdressing is the biggest mistake that beginners (and, frankly, experienced people) make.
Over the last 15 years, through much trial and error, I have come up with a clothing chart for myself that is foolproof. I will share this with you all in case you can find it useful. You may need to amend it slightly for yourself if you are particularly warm- or cold-blooded, but I consider myself fairly normal in terms of heat generation. If you are racing, you can move one step warmer (i.e. a 5K in 45 degree temps would require clothes from the 50-59 range). If you're walking at an easier pace, you can go down one step colder.
Perceived Temperature (Windchill) - Clothing Choices
60+ - Tank top and shorts
50-59 - T-shirt/tank top and shorts/capris
40-49 - Light longsleeve and shorts/capris/tights, light headband
30-39 - Light longlseeve and tights, headband, light gloves
20-29 - Medium longsleeve (sweatshirt or quarter-zip) and tights, headband/beanie, light/medium gloves
10-19 - Heavy longsleeve or two light ones, tights (possibly two layers), hat, gaiter/scarf optional, medium gloves
0-9 - Heavy and light longsleeve, two pairs tights, hat and gaiter/scarf, heavy gloves
Below zero - Jacket and two longsleeves, two pairs tights, lightweight pants, balaclava, heavy gloves
If it is cold and rainy/snowing, make your top layer a waterproof shell. Wear a brimmed hat with a beanie/headband on top.
Make sure your hydration-pack hose is well insulated in subzero temperatures, or choose to carry a bottle instead.
Always bring sunglasses just in case. They are helpful in sunny, windy, and rainy (paired with brimmed hat) conditions.
