To understand the fog, we must first look at the cloud. (Sorry, that will be the first and last weather-based half-pun). Proponents of fog computing point out that cloud can have inherent issues. Being data centre-based means there is latency in communications, and however small this might be, it can be a drag on computing that wants to get ever closer to real time.
OpenFog Consortium releases new forecast for fog at Internet of Business
OpenFog Consortium releases new forecast for fog at Internet of Business