Suppose that $\kappa$ is a strongly inaccessible cardinal, now force the continuum to be $\kappa^+$.
In the generic extension $\kappa$ is still a limit cardinal and still regular. However it is not a strong limit, so it is just weakly inaccessible.
Note, that if we have a weakly inaccessible cardinal then in some inner model it is strongly inaccessible, so this is really all the examples you can ask for which do not involve even stronger large cardinals.