Authorities investigating the helicopter incident that led to the tragic loss of Nigerian banker Herbert Wigwe mentioned that the conditions during the accident on Friday night “indicated the presence of rain and wintry mix.” Fatal plane crash involving Nigerian banker likely due to adverse weather.While a preliminary report on the crash should be available in a few weeks, the full NTSB investigation could take 12 to 24 months.Wigwe’s death has sparked an outpouring of grief from the African business community.Hebert, 57, his wife Dame Chizoba Wigwe, their senior son, and a close friend, Abimb…