Scraping noise when braking?

Is it normal to get a scraping noise when braking, when u first start off? Goes after 5 mins of driving though... Seems to be coming from rear brakes mainly. Ive looked at them and doesnt seem to be anything wrong, just dont like the sound of the scraping when i first start off.
 
In this weather it's probably just the rust that builds up on damp/wet discs. Nothing to worry about but worth checking the pad thickness too.
 
I was thinking it was to do with the weather but just wanted to be cautious and see if anyone else has the same thing
 
My drilled and grooved discs get very grindy sounding sometimes specially now in the cold, but worth a check to see if they wearing out as above :smile: