Memphis has a humid subtropical climate , with four distinct seasons, and is located in USDA Plant Hardiness Zone 8a in downtown, cooling to 7b for much of the surrounding region. Winter weather comes alternately from the upper Great Plains and the Gulf of Mexico, which can lead to drastic swings in temperature. Summer weather may come from Texas (very hot and humid) or the Gulf (hot and very humid). July has a daily average temperature of 82.8 °F (28.2 °C), with high levels of humidity due to moisture encroaching from the Gulf of Mexico. Afternoon and evening thunderstorms are frequent during summer, but usually brief, lasting no longer than an hour. Early autumn is pleasantly drier and mild, but can be hot until late October. Late autumn is rainy and cooler; precipitation peaks again in November and December. Winters are mild to chilly, with a January daily average temperature of 42.1 °F (5.6 °C). Snow occurs sporadically in winter, with an average seasonal snowfall of 2.7 inches (6.9 cm). Ice storms and freezing rain pose greater danger, as they can often pull tree limbs down on power lines and make driving hazardous. Severe thunderstorms can occur at any time of the year though mainly during the spring months. Large hail, strong winds, flooding and frequent lightning can accompany these storms. Some storms spawn tornadoes.
The lowest temperature ever recorded in Memphis was −13 °F (−25 °C) on December 24, 1963, and the highest temperature ever was 108 °F (42 °C) on July 13, 1980. Over the course of a year, there is an average of 4.4 days of highs below freezing, 6.9 nights of lows below 20 °F (−7 °C), 43 nights of lows below freezing, 64 days of highs above 90 °F (32 °C)+, and 2.1 days of highs above 100 °F (38 °C)+.
Annual precipitation is high (54.94 inches (1,400 mm)) and relatively evenly distributed throughout the year. Average monthly rainfall is especially high in March through May, and December, while August and September are relatively drier.