Inaccurate temperatures for Switzerland
Temperatures shown for Switzerland are off by almost 10°C. I stopped relying on your forecasts because they are highly inaccurate for this region. I have attached screenshots for reference for Canton Valais. I hope you'll be able to fix it.
I stopped relying on your forecasts
Windy do not make weather forecast. Forecasts here are provided by weather models.
Which models are you using? In mountains it is necessary to use high resolution models.
Have you tried ICON D2 with 2.2km resolution or AROME with 1.3 km resolution ?
For a local forecast try METEOBLUE, a very powerful Swiss weather model in the mountains.