I am trying to update information from a weather service on my page. The info should be updated every hour on the hour. How exactly do I go about calling a function on the hour every hour?

I kind of had an idea but im not sure of how to actually refine it so it works... What I had in mind was something like creating an if statement, such as: (pseudo code)

//get the mins of the current time
var mins = datetime.mins();    

if(mins == "00"){
    function();
 }