A method is outlined to diagnose temperature changes aloft from single Doppler radar data and an initial radiosonde observation. One aim is to deduce changes in inversion strength and stability between synoptic soundings, which is particularly important in forecasting thunderstorm initiation. A time sequence of wind profiles and horizontal wind gradients derived from VAD analyses are used to separate the wind into geostrophic and ageostrophic components. Horizontal temperature advection is then computed from the profile of geostrophic winds. Vertical advection is calculated from the vertical temperature gradient, and vertical air motion estimated from radar data. Parameterizations are used for diabatic heating and momentum fluxes in the convective boundary layer. Possible errors in the diagnosed temperature are estimated from uncertainties in data and the parameterizations used. Results of two test studies are presented with recommendations for future work.