On the detection of icing conditions at altitude in conjunction with mesoscale convective complexes using balloon sondes

Data collection from each flight is usually terminated when the balloon bursts at an altitude above 20 km. This paper highlights cases where the balloon's turnaround occurs at lower altitudes and is associated with ice formation on the balloon, a weather condition of interest to aviation safety.

Four examples of such cases are shown, where the balloon oscillates between 3-and 6-km altitude before rising to high altitudes and bursting. This oscillation is due to the accumulation and melting of ice on the balloon, causing the pattern to repeat multiple times. An analysis of National Weather Service radiosonde data over a 5-yr period and a global dataset from the National Centers for Environmental Information from 1980 to 2020 identified that 0.18% of soundings worldwide satisfied these criteria.