Eight AFGL thermosondes were flown from Mt. Haleakala, Hawaii to measure atmospheric turbulence in the form of the optical refractive index structure constant C sub n squared. Temperature and relative humidity comparisons between the AFGL instruments and standard GMD rawinsondes are presented. The AFGL instruments obtain greater temperature and humidity spatial resolution and consequently show finer structure in the profiles. A diurnal shift in the C sub n squared profile is noted as well as a tropopause enhancement. Coherence scales are calculated from the thermosonde data.