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Methanol (CH 3 OH) is an attractive alternative fuel that can reduce net carbon release and decrease pollutant emissions. In this study, methanol and n -dodecane spray flames were investigated using Large-Eddy Simulation (LES) and direct coupling with finite-rate chemistry. The selected ambient conditions are relevant to engines and were previously unreported for numerical methanol spray studies, i.e. high pressure (60 bar) and temperature (900 – 1200 K) with high injection pressure (1500 bar). The Engine Combustion Network (ECN) Spray A case was used to validate the n -dodecane spray flame. For methanol, a modified ECN Spray A condition was used with a high initial ambient temperature (1100 K-1200 K) to ensure fast enough ignition relevant to engine time scales. The performed homogeneous reactor (0D) simulations revealed a new phenomenon of a two-stage ignition process for methanol, confirmed by the 3D LES at high pressure, high temperature, and lean conditions. The present numerical results also show that: 1) there is a strong ambient temperature sensitivity for methanol ignition delay time (IDT) with a five-fold decrease in IDT (ID T 1100 K / ID T 1200 K = 5) and a factor of 2.6 decrease in the flame lift-off length (FLO L 1100 K / FLO L 1200 K = 2.6) as the ambient temperature is increased from 1100 K to 1200 K, 2) methanol spray ignition takes place at a very lean mixture (ϕ M R ≈ 0.2) consistent with the 0D predicted most reactive mixture fraction (Z M R) , 3) on average, methanol sprays are significantly leaner than n -dodecane sprays at quasi-steady-state (ϕ m e o h , a v e ≈ 0.2 vs ϕ n d o d , a v e ≈ 0.7) , implying very low soot emissions, and 4) the methanol spray flames could have similar temperatures as the n -dodecane sprays depending on the initial conditions, thus a similar level of NO x emissions. [ABSTRACT FROM AUTHOR]