Full Idea
One type of necessity may be said to be 'stronger' than another when the first always entails the second, but not conversely. This will obtain only if the possibility of the first is weaker than the possibility of the second.
Gist of Idea
A strong necessity entails a weaker one, but not conversely; possibilities go the other way
Source
Bob Hale (Absolute Necessities [1996], 1)
Book Reference
-: 'Philosophical Perspectives' [-], p.94
A Reaction
Thus we would normally say that if something is logically necessary (a very strong claim) then it will have to be naturally necessary. If something is naturally possible, then clearly it will have to be logically possible. Sounds OK.