A system is provided and includes a fuel module that, based on a crankshaft angle of an engine, generates a value indicative of an amount of fuel burned in a cylinder or a change in the amount of fuel burned. A heat release module, based on the value, determines an amount of heat released during a combustion event of the cylinder. A pressure module, based on the amount of heat released, estimates a pressure in the cylinder. A temperature module, based on the pressure, estimates a temperature in the cylinder. A concentration module, based on the pressure or the temperature, estimates nitrogen oxide concentration levels in the cylinder. An output module, based on the nitrogen oxide concentration levels, estimates an amount of nitrogen oxides. A control module, based on the amount of nitrogen oxides out of the cylinder, controls operation of the engine or an exhaust system.