Data can be exported from the app as CSV format, which can be opened in Excel and many other data software platforms.
If you tap a sensor in the "Current Conditions" home screen, you're taken to a screen with details about that sensor. Scroll all the way down below the graphs to the bottom of that screen. There you will find a button that allows you to download all the data as a spreadsheet in CSV format which works with Microsoft Excel and other spreadsheet software.
You'll be able to email the spreadsheet(s) to yourself once it finishes compiling.