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<p>Vertical ascent rate <span class="inline-formula"><i>V</i>_B</span> of meteorological balloons is sometimes used for retrieving vertical air velocity <span class="inline-formula"><i>W</i></span>, an important parameter for meteorological applications, but at the cost of crude hypotheses on atmospheric turbulence and without the possibility of formally validating the models from concurrent measurements. From simultaneous radar and unmanned aerial vehicle (UAV) measurements of turbulent kinetic energy dissipation rates <span class="inline-formula"><i>ε</i></span>, we show that <span class="inline-formula"><i>V</i>_B</span> can be strongly affected by turbulence, even above the convective boundary layer. For “weak” turbulence (here <span class="inline-formula"><i>ε</i><i>≲</i>10⁻⁴</span>&thinsp;m<span class="inline-formula">²</span>&thinsp;s<span class="inline-formula">⁻³</span>), the fluctuations of <span class="inline-formula"><i>V</i>_B</span> were found to be fully consistent with <span class="inline-formula"><i>W</i></span> fluctuations measured by middle and upper atmosphere (MU) radar, indicating that an estimate of <span class="inline-formula"><i>W</i></span> can indeed be retrieved from <span class="inline-formula"><i>V</i>_B</span> if the free balloon lift is determined. In contrast, stronger turbulence intensity systematically implies an increase in <span class="inline-formula"><i>V</i>_B</span>, not associated with an increase in <span class="inline-formula"><i>W</i></span> according to radar data, very likely due to the decrease in the turbulence drag coefficient of the balloon. From the statistical analysis of data gathered from 376 balloons launched every 3&thinsp;h at Bengkulu (Indonesia), positive <span class="inline-formula"><i>V</i>_B</span> disturbances, mainly observed in the troposphere, were found to be clearly associated with <span class="inline-formula"><i>R</i><i>i</i><i>≲</i>0.25</span>, usually indicative of turbulence, confirming the case studies. The analysis also revealed the superimposition of additional positive and negative disturbances for <span class="inline-formula"><i>R</i><i>i</i><i>≲</i>0.25</span> likely due to Kelvin–Helmholtz waves and large-scale billows. From this experimental evidence, we conclude that the ascent rate of meteorological balloons, with the current performance of radiosondes in terms of altitude accuracy, can potentially be used for the detection of turbulence. The presence of turbulence complicates the estimation of <span class="inline-formula"><i>W</i></span>, and misinterpretations of <span class="inline-formula"><i>V</i>_B</span> fluctuations can be made if localized turbulence effects are ignored.</p>