April, when all four seasons happen in one day
Short answer: Three thin layers and a light jacket cover five to eighteen degrees. It is the only system that handles a day that starts in frost and ends in sunshine.
Morning and afternoon are two different seasons
In the morning frost sits on the windows, by afternoon it can be eighteen degrees in the sun. Without layers you dress wrong for half the day, either too warm at lunch or too cold cycling to work. See bamboo clothing for women.
The inner layer stays the same all day
Only the outer layers need changing through the day. The inner one has to move moisture from both the cold morning ride and the sweat of the afternoon sun. A good inner layer is therefore the piece worn most often per week in April. See bamboo undershirt for women.
Something you can carry in your hand
A layer you can tie around your waist or put in your bag is more useful than a thick jacket that gets too warm by midday. Choose a mid layer that takes little space and comes off easily, rather than something you are stuck wearing all day long.
Socks change first
Switch to thinner socks before you switch jackets. Feet notice the season change first because they sit closest to shoe and pavement, where the sun's warmth gathers first in spring. See bamboo socks for women.
The bike ride is colder than the rest of the day
Morning air against the body while cycling feels several degrees colder than the same temperature standing still. Wind resistance pulls heat away faster than you can notice it. A thin windproof layer over the inner one solves this without sweating once you arrive.
The bag becomes the small wardrobe
Because temperature changes so much in April, the bag ends up working like a small cupboard. Pack an extra layer in the morning even if it feels unnecessary in the sun, since afternoon rarely looks like morning did.
Sun feels warmer than the thermometer shows
Direct sun in April warms the skin more than air temperature alone explains, because the air is still cold enough to keep shade cool. That creates big differences between the sunny and shaded side of the same street, which layers need to keep up with.
A T-shirt under the jacket is enough at lunch
At midday, if the sun is out, a thin layer under a light jacket is often plenty. Do not overdo the layers just because morning was cold, or you end up carrying the jacket for the rest of the afternoon. See bamboo t-shirt for women.
The evening ride home looks like morning again
Once the sun sets, temperature falls quickly back toward morning levels. If you packed a layer earlier in the day, the ride home is solved without freezing on the last stretch of cycling.
Frequently asked questions
How should you dress in April?
Three thin layers and a light jacket. That covers the whole day's temperature range, from morning frost to afternoon sun, without changing your entire wardrobe.
When should the winter jacket go away?
Once daytime temperature stays above ten degrees most of the day. Before that, several thin layers are more practical than one thick winter jacket.
What gets swapped first in spring?
Socks and the outer layer. The inner layer can stay the same all year, since its job stays the same regardless of temperature.
You can find the full range at Bamboo-Clothing.com.
