I wouldnt do it in direct sunlight, as pointed out above polish/waxes will go like concrete or just smear like a bitch.

Do it in the shade!!!

warmth is fine but baking hot aint good for paint or laquer, it will go pourous quite quick,, plus the sun glare off the panels/glass will be like arc eye


If U got a quiet multistorey car park local then pop down,...
£3 for all the shaded goodness you need to do a pukka job

Ive done it many a time