Why Does It Always Rain On Me (At The Weekend)

I have the whole weekend off this week so i was looking at my weather app and saw that it said Rain for Saturday and Sunday which made me think, is that old myth that it rains more at weekends due to the weekday pollution hold water, so i cornered a Meteorologist who poohed-poohed it out of hand.
He explained, very patiently considering he was faced with a woman waving the BBC Weather App on her mobile phone at him, that the effect of the week's pollution is negligible as there was no discernible pattern of particularly rainy days in any given week and whether we get rain depends on other variables such as the Jet Stream and where the clouds form.
'It's psychological' he said, 'because we are out and about more at the weekend rather than in an office, when we are told it's going to rain when we are off, than it feels worse than if we are told its going to rain on Wednesday when we are shackled to our desks'.
Annoyingly that all makes sense but he did admit that although no day is preferable for raining, it does tend to rain more in the afternoons due to the morning Sun heating the surface of the Earth making the warm air rise and form clouds which then piddle down on us on our way home from work.
I guess as he is  an expert i should believe him but i still swear it rains more at the weekend and even more bloody annoying, this weekend!