Rain temperature can vary significantly from ground-level air temperature due to vertical temperature gradients and phase changes in the atmosphere, making this a matter of everyday observation and meteorological science requiring no formal citation.
The claim states that rain temperature can vary significantly from ground-level air temperature. This is a matter of common physical observation and atmospheric science, as precipitation forms at high altitudes where temperatures differ substantially from ground level and can acquire different temperatures as it falls. Therefore, per the guidelines, this is classified as COMMON_KNOWLEDGE, requiring no papers and leaving index lists empty.