The first set of high and low temperatures are averages for 2010 to 2019. Everything else here is based on 1991 to 2020 weather. Number of days each year when the temperature in Myrtle Beach dropped to 32 or below, or rose to at least 70 or 90 degrees Fahrenheit; 32 °F 0 °C Year 70 °F 21 °C 90 °F 32 °C; 32: 2022: 233: 18: 25: 2021: 238: 5: 17: 2020: 251: 34: 18: 2019: 234: 29: 30: 2018: 221: 10: 20: 2017: 245: 14: 29: 2016: 240: 31: 35: 2015: 248: 26: 45: 2014: 216.