Freezing rain was reported in Nome at the time of the crash. A large weather front over Western Alaska created the potential for ice buildup as the plane neared the airport, according to the NTSB report.

The regional airline flight in Alaska that crashed, killing all 10 people onboard, was overweight before it took off, according to a preliminary report released Wednesday by the National Transportation Safety Board.

It isn’t yet clear what specific role the weight might have played in the Bering Air Cessna Caravan’s crash, and whether other factors were involved.