The following is my opinion about, and how I practice, winter cycling. If you disagree, please post an answer with your opinion.
----No risk of frost----
Riding on a road bike with the usual tires
Down to 15°C~60°F
- A (thin) long-sleeve jersey
Down to 10°C/50°F
- A thin wind-breaking hat under the helmet
- Full-finger, wind-sealing, gloves
- A thermal long-sleeve jersey
- Thin bib pants or thin cycling pants
- Neoprene (or other) shoe covers
Down to 5°C~40°F
- (1) Baselayer top (or thermal cycling jersey)
- A light wind-breaking jacket, with a ventilated back
- Cycling pants, bib pants, or fleeced bib pants
- Winter gloves
- Wool socks
- At this point it will be all too easy to omit packing water. Don't!
Down to 2°C~35°F
- A jacket, ideally with zippers to customize heat- and sweat-escape
----Risk of frost----
Riding on any bike that can take studded tires
Down to -2°C/28°F
- Studded tires (on hybrid, gravel, moutain, or fat- bike) —
a 5-meter stretch of black ice on a 30-km ~ 20-mile ride is enough to take
- (1) A baselayer top and bottom
- (3) Winter cycling boots over regular cycling socks (attaching with SPD, not SPD-SL)
- Skiing gloves
Down to -5°C~25°F
- A balaklava—both to protect the face and to warm the air before breathing it
- Glasses are even more critical, as they will protect the eyeballs from incoming wind
- Wool socks under winter cycling boots
- (2) Heated (chemical, electric) gloves
Down to -10°C~15°F
- A skiing helmet handily solved a difficult problem I was having. The eyes get so cold from the draft incoming on the side of cycling/vision glasses, it becomes necessary to blink for increasingly longer durations, which is by itself dangerous. Skiing goggles, which fit by design a skiing helmet, solve this problem nicely. A skiing helmet does reduce side visibility, but just like one adapts while skiing by glancing occasionally left/right to make sure no crazy skier is flying down the slopes, one also adapts by glancing sideways while biking.
- Heated (chemical, electric) gloves at a higher setting
- A midlayer
Switch to skiing and enjoy warming up frequently.
What is a baselayer?
Since you mention you grew up in warmer climate, it's worth stressing
that a "baselayer" is not at all the same thing as "long johns" (or
their equivalent top). Long johns are made from cotton. They
accumulate sweat during a workout and make one shiver. A baselayer is
made from a technical fabric that keeps one dry by pulling sweat away
from the skin. A quality baselayer is expensive, but it will last a long
time. For very cold weather you'll need one made from Merino wool.
Otherwise synthetic fibers are enough.
What is a midlayer?
A midlayer is a generic term for a fleece sweater, or anything you
wear between a baselayer and a jacket/windbreaker.
You didn't ask about riding in sub-freezing temperatures, but I went
ahead and summarized those as well, partly as a note to myself because
I still occasionally over-dress and return home from a winter ride
with a soaked back.
Frostbite is a dangerous
condition. If it's below freezing and you can no longer feel your
fingers, take shelter and put your hands under cold or tepid (never
Accumulating so many clothing items for cycling is expensive. I
numbered the three most important items.
You can delay winter cycling boots by inserting aluminum foil
underneath your soles. It will reflect heat back to your feet. (This
is not a permanent solution; the foil disintegrates every one or two
You can avoid winter cycling boots if you buy MTB cycling shoes that
are one size too large, wear lavishly thick wool socks, and wear
wind covers over the shoes. This is basically how winter cycling shoes
are constructed. Their main advantage is to make it possible to
get ready more swiftly.
With so many different items of clothing, avoid the color black, or
else you will only see a sea of black on your shelves, and it will be
hard to discern one item from another without unfolding. The
alternative is to use labeled organizer buckets. (Same problem with
white, but cycling clothing is not commonly in this stain-prone color.)
Wind is a much bigger problem. As a rule of thumb, wind speed of 30-40
kph ~ 15-25 mph is the limit for a tolerable "wind chill" (the
temperature as we feel it, taking into account the wind's cooling
Glancing at the reading of a remote thermometer positioned in the
shade just outside your dwelling is much more helpful than the
forecasted temperature or that at the nearest airport.
You'll still need to refer to the weather report for the expected wind speed.