Weather

There is no desktop weather application. There is a Notification center weather widget that you can gain access too by clicking the time in the menu bar. That slides out the Notification center. At the bottom of that panel is a lozenge entitled Edit Widgets. That opens a panel center screen with various widgets you can select. Scroll down until you locate the Forecast widget. When you rollover that widget, a green check box will appear, which you click to add the Forecast widget to Notification center.

As you probably could care less for the weather in Cupertino, or Santa Clara, right-click on the Forecast widget in the Notification center and select "Edit Weather." Click on the Location name, and then either enter your city, city and country code, or select My Location if you have location services on. Click done.