White Spots on Car Paint

[FOURRINGS7]

Hi, hopefully someone on here can help me.

Recently I realised after the rain, it has left these white spots on the car after i dried it. I first thought it was just the shade and all but now on a sunny day I see that it's left white marks. Even a hard scrub won't remove them so I really need some advice on what to do if someone can help. Attached is a picture. Shows relatively of the spots.

Thanks in advance.

 

[HansfishS3]

What are you scrubbing it hard with?! Try some cutting compound, something not that abrasive e.g Meguiars Ultimate Compound

 

[HansfishS3]

Maybe even before that try some quick detailer

 

[FOURRINGS7]

Tried it but it's still the same?
I can't physically feel the white dots. Could it be to do with the paint?

 

[Jake 61]

I have the same on my roof, (although, nowhere near as bad).
I have, so far, tried quick detailer, cutting compound, clay bars and lots of elbow grease.
Nothing has shifted it. It is a lot less noticeable after the above, but still does my head in as to how or what caused it.
It's not bird $hit, because that's not on the car long enough to even get cold...!

 

[FOURRINGS7]

I just don't get how the fudge it came up? I've had the car for 2 years and after yesterdays certain rain it's all over the driver side and not the passenger side of the car lol.

Going to see a bodyshop soon though and find out what it is, will keep it posted on here.