Central German dialects
Hessian (Ger.: Hessisch) is a West Central German group of dialects of the German language in the central German state of Hesse. The dialect most similar to Hessian is Palatinate German (Ger.: Pfälzisch, pronounced [ˈpfɛltsɪʃ]) of the Rhine Franconian sub-family. However, the Hessian dialects have some features which set them somewhat apart from other West-Central German dialects.
Hessian can be divided into four main dialects, namely those of:
Northern Hesse (around the city of Kassel),
Eastern Hesse (around Fulda),
Southern Hesse (around Frankfurt).
To understand this division one must consider the history of Hesse and the fact that this state is the result of an administrative reform.
Southern Hessian 
- Changes to consonants