Preflight planning is a very important element of any flight and especially so when going on a cross country flight. There are a number of items to be done in preparation for a VFR cross country in such a way that nothing is overlooked and the intended flight is done as safely as possible.
Applying weather weather information in your flight planning is mandatory for accurate navigation and performance calculations. The document below descibes some common tips.
Eurocontrol Guidance Notes
Excerpt from the document:
For accurate navigation, you will use the forecast winds and temperatures at your planned altitude to calculate your required headings and times between turning points and fix points, which will also allow you to calculate how much fuel you will use.
Most forecasts only provide information at set altitudes, which are unlikely to be the ones you intend flying at. For accurate calculations, you should interpolate between the figures for the altitudes above and below you,
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