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You can see this in the Weather Type Setup tab in the weather module of Flow:

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Day-Part Name Editing

You probably shouldn’t bother editing the part names because the reader may provide the current part name applicable to each part.

These day-part forecasts have a Part Name associated with them to allow you to enter an appropriate name in case the default isn't suitable. However changing this name doesn’t change what forecast type it is.  For example if you have more room and you want to label Morning as This Morning or you want to display an abbreviation instead like Morn. and Aft. and Eve (for Morning Afternoon and Evening respectively). The player relies on the forecast type codes and not the part name that you can type in. So it is always looking for forecast part2 to display as the afternoon data. So while you change it to have part name = Morning saved in the part2 forecast the player still uses part2 as the afternoon.

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