How to exit a function embedded in an $.each() block?

Sorry but, I've had a look at similar posts on Stack Overflow and could not find my exact situation.

I'm iterating on a bunch of images and I want to exit as soon as I find the one meeting my specifications. Trouble is, I need to use an 'onload' event to test that.

I don't know how to break out of my innermost function: the each() loop always iterates on all items, even though the second image fits the bill. Here's the jsfiddle: you will see 3 alerts, one for each iteration. http://ift.tt/13Zhhzw

If anyone could guide me, that would be awesome! Thx.

// A bunch of images
var arrImages = ["http://ift.tt/1vK2Ne6","http://ift.tt/13ZhhPK","http://ift.tt/1xxmhsG"];

// Iterate until I find the first one meeting my specs
$.each(arrImages, function(i,item) 
{
    extension = item.slice(-(3)).toLowerCase();
    if (extension == "jpg")
    {
        // Test image size
        newImg = new Image();
        newImg.onload = function() 
        {           
            if (this.width > 600 && this.height > 900)
            {
                // All right! That's the one. Set it as src on my web page
                $("#MyImgBg").attr("src",this.src);
                return false; // trying to break out - not working
            }           
        };
        newImg.src = item;
    }

    // I expected this alert to popup only twice
    alert(i); 

});