Read the statement by Michael Teeuw here.
Hourly forecast for weather forecast module
It is so obvious, that it might already exist and I may be just to dump to find it, but: would it be possible to get the weather forecast module to display the weather forecast hourly instead of daily? I know you can get weather data for every 3 hours with the free openweathermap API, so it should be possible to show it, shouldn’t it? Maybe by adding an additional config option to switch between modes?
You could try https://github.com/RedNax67/MMM-WunderGround instead and configure it to show hourly forecast
Weather Underground has stopped providing API keys. Is there a different solution?
Search for MMM-forecast.io here in the forum.