Damp/wet wall help

I live in an end terrace house and this is the first winter I've had bare plastered walls (previously papered) these last few weeks I have noticed 2 patches above the skirting board where the walls are wet when it has been heavily raining outside. Can anyone advise me as to what this is likely to be and where I would turn to for advice about fixing the problem. Thanks

Hi we are a company that specializes in various defects and remedial work. We could assess the damp and provide a solution at no cost to yourself. We can provide references. I look forward to hearing from you. Kind regards. Julie

Is there a window above this damp patch?