  We present wind and temperature profiles at Dome C measured by balloon born
sonds during the polar summer. Data from 197 flights have been processed for 4
campaigns between 2000 and 2004. We show the exceptionnal wind conditions at
Dome C, Average ground wind speed is 3.6 m/s. We noticed in mid-november the
presence of high altitude strong winds (40 m/s) probably due to the polar
vortex which disappear in summer. These winds seem to have no effect on seeing
measurements made with a DIMM at the same period. Temperature profiles exhibit
a minimum at height 5500 m (over the snow surface) that defines the tropopause.
Surface layer temperature profile has negative gradient in the first 50 m above
ground in the afternoon and a strong inversion layer (5{\deg}C over 50 m)
around midnight. Wind profiles are compared with other astronomical sites, and
with a meteorological model from Meteo France.
