How to change temperature in Today's Summary part from F to C in Notification Center I'm using Mac OS (El Capitan) and in Notification center, Today's Summary part it shows weather information. I want to change from F to C here. My weather widget is already in C and working fine.
Open System Preferences
Click Language &amp; Region
Select Advanced
Change Measurement units to Metric


Add-on note: You may have to do this a couple of times or cycle through the options to make it stick.