The filtered mass density function (FMDF) model (Jaberi et al. 1999 [1]) is employed for large eddy simulations (LES) of "high speed" partially-premixed methane jet flames with the "flamelet" and "finite-rate" kinetics models. The FMDF is the joint probability density function (PDF) of the scalars and is determined via the solution of a set of stochastic differential equations. The LES/FMDF is implemented using a highly scalable, parallel hybrid Eulerian-Lagrangian numerical scheme. The LES/FMDF results are shown to compare well with the experimental data for all flow conditions when "appropriate" reaction and mixing models are employed. (C) 2009 Elsevier Ltd. All rights reserved.