Mongoose Store db.collection.count() into variable

So I am working with Node.js and I need to render an HTML with some data from a collection of my mongoose db, I understand that db.count() is asynchronous so when i do something as follows:

Car.getCount("a", function(err, ocupados){
    if(err) throw err;
    parqOcupados.push(ocupados);
});

Oh and my getCount function is:

module.exports.getCount = function(lugar, callback){
var query = {lugar: lugar};
Car.count(query, callback);}

I will eventually get undefined pushed into the array since the function is asynchronous as mentioned above. What would be a way to get the value for my getCount pushed into my Array in a correct form?

Thanks in advance for any help provided

via Juan David Ospina