IT is freezing cold, the New Year diet has been ditched and it is still far too long until pay day.

Today is Scotland's most depressing day of 2015 - and Black Friday debt will make Blue Monday even more miserable, according to a psychologist.

Happiness guru Dr Cliff Arnall fed every date of the year into a mathematical equation which showed the third Monday in January - today - has the highest depression score of any date in 2015.

Numerical ratings were given to 'gloom factors' including mounting credit card bills - worsened by Black Friday's late-November shopping frenzy which deepened debt.

Dr Arnall said other depressing factors peaking today include the wait until January's pay-day, snow and storms, fading Christmas memories, forgotten New Year's resolutions and low motivation.

Dr Arnall, 49, from Brecon, Wales, who runs happiness clinics for celebrities, the NHS and businesses, said: "Black Friday is a key impact on 2015's most depressing day of the year - as even bigger loan repayments and credit card bills are arriving now.

"Christmas shopping being extended into November caused pressure to spend more. And only a small percentage of Black Friday shoppers actually got bargains, while some witnessed violence.

"The economy's improvement has encouraged consumer confidence and generated spending - but the downside is people are now paying for it."