How to add in "working times" if statement a specify holiday dates

I try to figure out how in to the code "if statement" add a specific day(official holiday dates) in month when business does not work. Now it's code works if day is Mon, Tue, Wed, Thu, Fri and time is from 09:00 to 15:00 in 24 h format. But I want in addition add holiday: For example "*if day and month is equal with 01.01 (1 January) * then will be "else" conditions.

html

        <span id="date_time"></span>
        <script type="text/javascript">window.onload = date_time('date_time');</script>

Script

 function date_time(id)
{
    date = new Date;
    year = date.getFullYear();
    month = date.getMonth();
    months = new Array('Janvāris', 'Februāris', 'Marts', 'Aprīlis', 'Maijs', 'Jūnījs', 'Jūlījs', 'Augusts', 'Septembris', 'Oktobris', 'Novembris', 'Decembris');
    d = date.getDate();
    day = date.getDay();
    days = new Array('Svētdiena', 'Pirmdiena', 'Otrdiena', 'Trešdiena', 'Ceturtdiena ', 'Piektdiena', 'Sestdiena');
    h = date.getHours();
    if(h<10)
    {
            h = "0"+h;
    }
    m = date.getMinutes();
    if(m<10)
    {
            m = "0"+m;
    }
    s = date.getSeconds();
    if(s<10)
    {
            s = "0"+s;
    }
      if ((day == 1 || day == 2 || day == 3 || day == 4 || day == 5 ) && h >= 9 && h <= 14) {
       result = 'Ir '+days[day]+' '+year+'.'+d+'.'+months[month]+' '+h+':'+m+':'+s+' ēdnīca ir atvērta!' ;
       document.getElementById("date_time").style.backgroundColor = '#27ae60';
  } else {
       result = 'Ir '+days[day]+' '+year+'.'+d+'.'+months[month]+' '+h+':'+m+':'+s+' ēdnīca ir slēgta!' ;
       document.getElementById("date_time").style.backgroundColor = 'rgba(231, 76, 60, 0.85)';
  }

////////////

  var now=new Date();
  var weekday=new Array(7);
  weekday[0]="Svētdiena";
  weekday[1]="Pirmdiena";
  weekday[2]="Otrdiena";
  weekday[3]="Trešdiena";
  weekday[4]="Ceturtdiena";
  weekday[5]="Piektdiena";
  weekday[6]="Sestdiena";

var checkTime=function(){
var today=weekday[now.getDay()];
var timeDiv=document.getElementById('timeDiv');
var dayOfWeek=now.getDay();
var hour=now.getHours();
var minutes=now.getMinutes();
var suffix=hour>=24?"":"";
if(minutes<10){minutes="0"+minutes;
}
if((dayOfWeek==1||dayOfWeek==2||dayOfWeek==3||dayOfWeek==4||dayOfWeek==5)&&hour>=9&&hour<=14)
{
    timeDiv.innerHTML='Ir '+today+' '+hour+':'+minutes+suffix+' - ēdnīca "Līdaciņa" ir atvērta!';timeDiv.className='atverts';
}else{
timeDiv.innerHTML='Ir '+today+' '+hour+':'+minutes+suffix+' - ēdnīca "Līdaciņa" ir slēgta!';timeDiv.className='aizverts';
}
};
  var currentDay=weekday[now.getDay()];
  var currentDayID="#"+currentDay;
  $(currentDayID).toggleClass("today");setInterval(checkTime,1000);checkTime();

P.S I have this error TypeError: timeDiv is null