The Diocese received this report from Fr. Anthony Nelson, rector of the St. Benedict Orthodox Church
in Oklahoma City on Monday, May 20th:

It took less than one hour for clear sunny skies to spawn a tremendous
thunder storm with baseball-size hail and drenching wind and rain...and a
F-5 tornado. The national media is still covering it almost full-time as
this is written four hours after the storm. So far at least 37 deaths have
been counted, including some 30 small children in an elementary school
flattened by the tornado, which was 2-miles wide. Many more deaths - both in
the school and along the 10-mile path of the tornado are expected to be
discovered.
 
The tornado passed within four miles of St. Benedict Church, but the parish
suffered no damage. All parishioners except one couple are accounted for,
and we believe that they are out of cell-phone range because of the damaged
telephone infrastructure.
 
Please remember the victims of the disaster in your prayers as the
death-count continues to mount.

As of Tuesday, May 21st, Fr. Anthony adds that the remaining 2 parishioners have been accounted for and the IOCC has already 
reached out to the local Orthodox community in the Oklahoma City area to offer assistance.