I am by no means an expert, but I will make a couple comments.
As someone else pointed out, with your location on Long Island you are in the cat-bird's seat for hearing Europe and Africa on MW. Other MWDXers on the East Coast can probably tell you what to look for to help predict when condx will be good. In any event, you can hear stuff I only dream of hearing in Kentucky.
Another consideration is geomagnetic disturbances. These tend to reduce propagation to the north. So, a good aurora can cause a station to your north that is ordinarily loud to be weak or non-existent. This can allow you to hear other stations on the same frequency that you would ordinarily be unable to hear.
If you see relatively high K-index numbers, or hear reports of aurora, it is time to check to see if your northern "pests" are weakened any.