The half-light problem
Fully dark and fully light are, in some ways, easier than the stretch in between. At dusk and dawn the sky can still look bright while the road beneath trees and buildings is already murky. Your eyes are partway through adjusting, drivers are squinting against low sun or dazzled by headlights, and a cyclist in dull clothing can be nearly invisible against a grey background.
Riding in these periods is risky for a simple reason: it feels safe because you can still see, so it is easy to leave your lights off or to keep riding at daytime speed. This article is about that transition, and about planning rides that cross it. Our main guide to riding after dark covers the wider topic of lights, kit and route choice.
Know when the light changes
The first step is to look up sunset and sunrise times for your area and remember that they change through the year. In autumn, the evening commute can go from daylight to dusk within a few weeks, which catches many people out. The sky usually stays bright for a while after the sun sets, but road level gets dark sooner than you expect, especially in cities with tall buildings or on tree-lined lanes.
A useful habit is to check the forecast and the sunset time in the morning and ask: will any part of my ride happen in fading light? If the answer is yes, take your lights along and plan to use them.
Switch your lights on early
A common rule of thumb among cyclists is to put lights on before you think you need them, since lights are about being seen, not only about seeing. A steady front and rear light costs you very little and makes you much easier to spot against a dim background. Local laws on when lights must be used vary, so check yours, but riding with lights on at the edges of the day is generally a sensible choice whatever the rules say.
If you use daytime flashing modes, remember that a flashing light can be harder to judge for distance and speed, and it can be less helpful once it is properly dark. Our article on bike lights explains steady and flashing modes in more detail. Also follow the manufacturer’s guidance on mounting and charging, and do a quick light and reflector check as part of your routine.
Plan commutes around the light
When your commute starts in the dark or ends in it, a few adjustments make a real difference.
- Time your departure. If you can leave a little earlier in the evening, you may finish before the darkest part. Even small changes can move a tricky stretch into better light.
- Choose the route for the light. A route with street lighting, even if slightly longer, is often better at dawn and dusk than a short unlit shortcut. Better route planning means you know where the tricky sections are before you reach them.
- Think about the sun. In low sun, drivers coming toward you or from behind may struggle to see a cyclist, and you may struggle to see hazards. Slow down and be extra predictable at junctions facing the sun.
- Have a backup plan. If you are running late and the light is going, take the safer option, such as a lit main road, a bus or train for part of the trip, or a different day for that ride.
Commuting skills such as signalling, positioning and observing traffic are covered elsewhere on the site, so here the main idea is simply to allow more margin than you would at midday.
Dealing with glare and shadow
Fading light creates sharp contrasts. Low sun can dazzle you, while shaded patches under trees or bridges can seem almost black by comparison. When you move from a bright stretch into shade, ease off the speed for a moment and let your eyes adapt before you commit to a line.
Sunglasses with a light tint can help against low sun, but remove them or switch to clear lenses as soon as the light drops. Many riders keep a clear pair of glasses or a clear visor handy for evenings and for riding in the rain, as eye protection is useful against insects and grit too.
Wet surfaces often make shadows and reflections harder to read, so slow down and brake earlier and more gently. If conditions are poor enough that you cannot see road markings or potholes, that is a good reason to reduce speed further or stop and walk through a short difficult section.
Dawn rides
Early-morning starts have their own character. Roads are often quieter, but temperatures can be lower, leaves and surfaces may be damp or icy, and low sun can appear suddenly as you turn a corner. Dress for the temperature at the start, not the middle of the ride, and keep an eye on the surface, because frost can form in shaded spots even when the day will warm up. If there is any chance of ice, consider postponing.
Being seen at the edges of the day
At dusk and dawn, a mix of lights and visible clothing works well together. Light or bright colours help while there is still daylight, and reflective strips help once headlights are on you. Wearing something reflective on moving parts, such as ankles or wrists, can make a rider look more clearly like a person on a bike. None of this guarantees that you are seen, so keep riding as though some drivers have not noticed you.
A short checklist before you set off
- Check sunset or sunrise time and whether any of your ride falls in low light.
- Fit and test front and rear lights, and make sure they are charged.
- Wear a helmet and something reflective or bright.
- Pick a route you know, with lighting if possible.
- Allow extra time so you are not tempted to hurry.
When the days are short, riding in low light becomes a normal part of cycling. A little preparation turns those awkward minutes into an ordinary part of the journey, and nothing about it needs to be rushed.