radiosonde

noun1

1. •
   A miniature radio carried aloft (e.g. by an uncrewed balloon, an airdrop from a crewed aircraft, or a sounding rocket) to automatically transmit measurements of the upper air such as the wind speed, pressure, temperature, and relative humidity to a receiving station on the ground.

   • Thus, the performance characteristics of radiosondes and the relative accuracy of radiosonde winds have been the subject of a great deal of scrutiny over the last few decades. — 2000