opportunely

from WordNet (r) 3.0 (2006)

opportunely
    adv 1: at an opportune time; "he arrived rather opportunely just
           when we needed a new butler" [ant: {inopportunely},
           {malapropos}]

from The Collaborative International Dictionary of English v.0.48

Opportune \Op`por*tune"\, a. [F. opporiun, L. opportunus, lit.,
   at or before the port; ob (see {Ob-}) + a derivative of
   portus port, harbor. See {Port} harbor.]
   Convenient; ready; hence, seasonable; timely. --Milton.
   [1913 Webster]

         This is most opportune to our need.      --Shak.
   [1913 Webster] -- {Op`por*tune"ly}, adv. --
   {Op`por*tune"ness}, n.
   [1913 Webster]