Portland Police "Hot Spots"

Recently I have been hearing officers calling in that they "cleared the hot spot" or making traffic stops in connection to "their hot spot"...



This is something I have only been hearing recently, most often on the North talkgroup. (its the one I listen to most often since I live in NE Portland.)



I have also used to once in a while hear a dispatcher come over the air and say that "citywide is "hot", but I have not heard that in over a year now.



So, my question is: what is this "hot spot" and what does it mean?



Thanks in advance.