Examples of the present application disclose memory systems, methods of operating the same, and readable storage mediums. An example memory system includes a memory device and a memory controller coupled to the memory device. The memory controller is configured to: in response to a read command, determine a time period to which a time difference between writing and reading of data to be read corresponding to the read command belongs; determine an amount of the voltage shift according to the time period to which the time difference between the writing and reading of the data to be read belongs; and determine a read voltage for reading the data to be read based on the amount of the voltage shift and the default read voltage.