<script type="text/javascript">
var date = new Date();
var hours = date.getHours() + date.getTimezoneOffset()/60;
var mess=''
if(hours<2){mess = 'Понедельник';}
else if(hours < 6){mess = 'Вторник';}
else if(hours < 9){mess = 'Среда';}
else if(hours < 13){mess = 'Четверг';}
else if(hours < 16){mess = 'Пятница';}
else if(hours < 20){mess = 'Суббота';}
else {mess = 'Воскресенье';}
document.write(mess);
</script>