|30°F ... 10°F||seasonal||Every winter|
|10°F ... 0°F||chilly|
|0°F ... -10°F||cold|
|-10°F ... -20°F||very cold|
|-20°F ... -30°F||bitterly cold||All winters but one|
|-30°F ... -40°F||brutally cold||~25% of winters|
|-40°F ... -50°F||temperatures that must not be named||~10% of winters|
|< -50°F||never experienced||0% of winters|
Temperatures in Fahrenheit because it is a more human-centric scale (i.e., below 0 feels cold, above 100 feels hot).
I've been out at -46°F. If you think you've been out where it's colder, remember this doesn't indicate wind-chill, which is a bunch of hooey. I've skied (at >30mph) at -44°F. According to NOAA, that's -90°F, but that's not how cold works. Cold is tough because it changes the nature of things in the environment—wind chill has no effect on these physical properties.