26.27.211. Exclusive, continuing jurisdiction
(1) Except as otherwise provided in RCW 26.27.231, a court of this state that has made a child custody determination consistent with RCW 26.27.201 or 26.27.221 has exclusive, continuing jurisdiction over the determination until:
(a) A court of this state determines that neither the child, the child's parents, and any person acting as a parent do not have a significant connection with this state and that substantial evidence is no longer available in this state concerning the child's care, protection, training, and personal relationships; or
(b) A court of this state or a court of another state determines that the child, the child's parents, and any person acting as a parent do not presently reside in this state.
(2) A court of this state that has made a child custody determination and does not have exclusive, continuing jurisdiction under this section may modify that determination only if it has jurisdiction to make an initial determination under RCW 26.27.201.