<P> The state is classified as humid subtropical (Cfa) under the Köppen climate classification . The average annual temperature is 64 ° F (18 ° C). Temperatures tend to be warmer in the southern part of the state with its proximity to the Gulf of Mexico, while the northern parts of the state, especially in the Appalachian Mountains in the northeast, tend to be slightly cooler . Generally, Alabama has very hot summers and mild winters with copious precipitation throughout the year . Alabama receives an average of 56 inches (1,400 mm) of rainfall annually and enjoys a lengthy growing season of up to 300 days in the southern part of the state . Hailstorms occur occasionally in the spring and summer, but are seldom destructive . Heavy fogs are rare, and are confined chiefly to the coast . Thunderstorms occur throughout the year - they are most common in the summer, but most severe in the spring and fall, when destructive winds and tornadoes occasionally occur . Hurricanes are quite common in the state, especially in the southern part, and major hurricanes occasionally strike the coast which can be very destructive . </P> <P> Summers in Alabama are one of the hottest in the United States, with high temperatures averaging over 90 ° F (32 ° C) throughout the summer in many parts of the state . The heat of summer is tempered in the extreme south by the winds from the Gulf of Mexico which often blow inland by up to 10--15 miles, and in the north by the elevation above the sea . Afternoon high temperatures are highest in Montgomery (92.4 degrees daily from June through August) and in Tuscaloosa . The average nighttime humidity is highest in southwest Alabama, which results in the highest average (high plus low temperature) for reporting stations in the state . While afternoon highs in Mobile are cooler than their inland sister cities, the remaining warm air trapped near the Gulf at night results in the average annual temperature for Mobiles being the highest in the southwest along the coast . Cool morning temperatures help keep the northeast highlands among the more temperate locations in the state and lowest in the northeast among the highlands . Thus at Mobile the annual mean is 67 ° F (19 ° C), the mean for the summer 81 ° F (27 ° C), and for the winter 52 ° F (11 ° C); and at Valley Head, in De Kalb county, the annual mean is 59 ° F (15 ° C), the mean for the summer 75 ° F (24 ° C), and for the winter 41 ° F (5 ° C). At Montgomery, in the central region, the average annual temperature is 66 ° F (19 ° C), with a winter average of 49 ° F (9 ° C), and a summer average of 81 ° F (27 ° C). The average winter minimum for the entire state is 35 ° F (2 ° C), and there is an average of 35 days in each year in which the thermometer falls below the freezing - point . At extremely rare intervals the thermometer has fallen below zero (- 18 ° C), as was the case in the remarkable cold wave of the 12th - 13 February 1899, when an absolute minimum of - 17 ° F (- 29 ° C) was registered at Valley Head . The highest temperature ever recorded was 111 ° F (44 ° C) in Centreville in 1925 . Close competing temperatures occurred in 2007 when during the August heat wave, three instances of official 108 degree heat were recorded at Maxwell AFB in Montgomery, each tying the all - time record for the capital city . Winters are generally mild in Alabama, as they are throughout most of the southeastern United States, with average January low temperatures around 40 ° F (4 ° C) in Mobile, around 31 ° F (− 1 ° C) in Huntsville, around 35 ° F (2 ° C) in Montgomery, and around 33 ° F (1 ° C) in Birmingham . </P>

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