Precipitating fluxes of energetic O+ ions during magnetic storms constitute a significant source of energy to the nightside thermosphere at altitudes above 200 km. The resulting perturbations of temperature and winds in the thermosphere due to energetic O+ precipitation are examined by computing the heating rate profile from such a precipitation event and using this as input to the NCAR thermospheric general circulation model. The results of a time dependent calculation show that heating due to energetic O+ ion precipitation produces a significant perturbation to the thermospheric structure above about 300 km. Energetic O+ precipitation events should produce considerable variability in the upper thermosphere during geomagnetic storms.