High Temperature Forecasts for Southern French Alps
Your forecasts high temperatures for the southern French Alps seem very low compared to actual temperatures and other forecasters. Compare the forecasts for Guillestre, for example.
Your forecasts.... Windy does NOT make any forecast. Windy visualise data from global weather models like that of ECMWF or GFS. Windy offers also in Europe limited area models like ICON, NEMS and AROME. AROME is a high resolution model from Météo France. Which model do you consider?
And which forecasters are you talking about? Show screenshots to give arguments to your statement.
Guillestre is located in mountains at 1000m and is surrounded by high summits 2500 to 3000m. In this situation global models with 9 km resolution and more cannot give good temperature forecast.
High temperatures ... do you mean Daily maximum temperatures?