Microsoft Visio - Customize the calendar
Microsoft visio tutorial
Microsoft Visio - Calendar customization
Calendars can be personalized like any other Visio drawing by applying themes and variations. Calendars can also be customized to show weather conditions or even moon phases.
To add a shape such as weather icons, scroll through the list of shapes in the Shapes pane and drag the desired icon to a date in the calendar. You can align multiple shapes using the dynamic grids that appear when you try to align the shapes next to each other.
You can also change the appearance of the calendar by selecting themes and variants in the Design tab of the ribbon.