A sonic anemometer (sonic) reports 3-dimensional wind and sonic temperature ( T s ) by measuring the time of ultrasonic signals flying along each of its three sonic paths whose geometry of lengths and angles in the sonic coordinate system was precisely determined through production calibrations and was embedded into the sonic’s firmware. If the sonic path geometry is deformed, although correctly measuring the time, the sonic continues to use its embedded geometry data for internal computations, resulting in incorrect data. However, if the geometry is re-measured (i.e. recalibrated) to update sonic firmware, the sonic can resume reporting correct data. In some cases, where immediate recalibration is not possible, a deformed sonic can be used because ultrasonic signal-flying time is still correctly measured. For example, transportation of a sonic to Antarctica in 2015 resulted in a geometrically deformed sonic. Immediate deployment was critical, so the deformed sonic had been used until a replacement arrived in 2016. To recover data from this deformed sonic, equations and algorithms were developed and implemented into the post-processing software to recover wind data with/without transducer shadow correction and T s data with crosswind correction. Using two geometric datasets, production calibration and recalibration, post-processing recovered the wind and T s data from May 2015 to January 2016. The recovery reduced the difference of 9.60 to 8.93 °C between measured and calculated T s to 0.81 to −0.45 °C, which is within the expected range due to normal measurement errors. The recovered data were further processed to derive fluxes. Since such data reacquisition is time-consuming and expensive, this data recovery approach is a cost-effective and time-saving option applicable to similar cases. The equation development can be a reference to the studies on related topics.