Cycling weather: is today a good day to ride?

Rates a bike ride from 6am to 9pm, headwinds and all. GoDay finds the best 2-hour ride of each day, and marks down dark hours, wet roads and ice.

What it weighs, most important first

1. Wind
2. Rain
3. Feels-like temperature
4. Gusts
5. Daylight
6. Rain in the last 6 hours
7. UV
8. Air quality
9. Visibility

Also on the page, but not in the score: wind direction.

What holds the score down

A thunderstorm holds the score at 2. Riding in the dark holds it at 5, and at dusk at 7. Rain over 2 mm an hour, gusts over 60 km/h (37 mph), a feels-like above 38°C (100°F), or a chance of ice (under 1°C on a road that has been wet) hold it at 3. Poor air quality (US AQI over 150) holds it at 4, and over 200 at 2.

Questions

How much wind is too much for cycling?

Up to 20 km/h (12 mph) barely counts. From 20 to 35 km/h (12 to 22 mph) you'll feel it, and past 50 km/h (31 mph) GoDay rates it a gale. Gusts over 60 km/h (37 mph) can push you off your line, so they hold the score at 3.

Does it know the roads are wet?

Yes. It looks at the rain in the last 6 hours, because roads stay slippery after the rain stops. A dry hour straight after a downpour still loses points.

Does it work for mountain biking?

Yes, the same rating works for trails. Keep an eye on the recent rain: trails stay muddy for longer than roads.