A turbine nozzle for a gas turbine includes: an airfoil having an airfoil shape having a nominal profile substantially in accordance with at least a portion of Cartesian coordinate values of X, Y and Z set forth in TABLE I. The Cartesian coordinate values are non-dimensional values of from 0% to 100% convertible to distances by multiplying the values by a height of the airfoil expressed in units of distance. The X and Y values are connected by smooth continuing arcs that define airfoil profile sections at each distance Z along at least a portion of the airfoil, and the airfoil profile sections at the Z distances are joined smoothly with one another to form the nominal profile. A trailing edge profile for a turbine nozzle is also disclosed.