RedactedNarrative: Vessel #1 was launched with one occupant on board; a second occupant launched another vessel in the same party.  Heavy thunderstorms and rain in the area had elevated water levels to posted flood conditions at the time of the incident.  Shortly after launching, the rough swift water resulted in the capsizing of both Vessel #1 and Vessel #2. The Operator of Vessel #1 was struck on the head underwater as the capsizing occurred and not wearing any form of head protection at this time.  The second vessel operator was able to swim to the Victim and attempt a self-rescue.  Both subjects were able to make it to shore. Both vessels were lost in the incident.  Both parties involved in the incident indicated that they were wearing PFDs prior to the incident, however, those PFDs were torn off due to the force of the water.
  
  Information on either vessel was unable to be obtained due to loss of the vessels.
  
  While the Operator had experience with the vessel type, there was no previous experience related to operation in these conditions.  this narrative reflects one of those vessels.