The weather in Outlook calendar is displayed in the wrong unit, Celsius C° instead of Fahrenheit F°, or the inverse, Fahrenheit F° instead of Celsius C° ?
Outlook calendar weather in Fahrenhait F° unitOutlook calendar weather in Celsius C° unit
To change it, open the File menu
Outlook File menu
There, go to Options
Options in File menu
and open the Calendar settings
Calendar menu in Outlook options
at the bottom, you’ll find the option to display the weather in the calendar (or not), and you’ll be able to select the correct unit to use