Dewpoint
There is almost always a good hour.
The problem is knowing which one. On a humid summer day the difference between 6am and noon is not a few degrees — it is whether the session goes well at all. Dewpoint reads the hourly forecast for where you are and ranks every window against the workout you actually have planned.
For iPhone. In TestFlight now.
A muggy August afternoon. The morning is out, the evening is not.
111°F in Phoenix. The middle of the day is ruled out, not dressed up.
Some days everything is fine. It will say that too.
What it actually looks at
Dew point
What decides whether sweat can evaporate, and the number that separates a pleasant 26°C from a brutal one.
Wet bulb globe temperature
The heat measure used in endurance sport. It combines humidity, radiant heat from the sun and air temperature, which is why a cloudy 29°C can be easier than a sunny 26°C.
Wind, for your activity
A rider makes their own headwind, so a still 5°C morning bites on a bike in a way it does not on foot. Dewpoint accounts for that instead of treating every activity the same.
How long roads stay wet
Rain that stopped at 6am still leaves a greasy road at 7. The drying is tracked with sun, wind and humidity rather than assuming a dry forecast means a dry road.
Light
A window that starts in the dark and finishes in daylight is not the same as one that does the reverse, and it is scored accordingly.
Air quality
Counted when it is known, and treated as unknown rather than clean when it is not.
Built around the session you actually have
Connect intervals.icu and each day fills in from your training plan, so a 40 minute recovery spin and a three hour endurance ride are judged differently — because they are different. No plan is fine too: tell it what you are doing and how hard.
Read your calendar and a booked hour is never suggested. All-day entries are ignored, so a birthday does not rule out a whole day.
Heat, humidity, cold, wind, rain and air quality each get a slider, and every activity keeps its own settings. The hours you would ride are not the hours you would walk.
- go
- caution
- poor
Honest about what it knows
Dewpoint works from a public weather forecast. It estimates heat stress rather than measuring it, and it says so on screen. A true wet bulb globe temperature needs an instrument where you are standing.
It will tell you when no hour is any good instead of dressing up the least bad one. Deciding whether to go out is still yours.
No account. No ads. No tracking. Your location goes to the weather service and nowhere else, rounded so it is never precise.