The Key West climate is a significantly mild climate that could be described as tropical savannah climate. This climate is due to the moderation of the Gulf of Mexico in the western and northerly directions. Key West is the only city in the 48 states in lower region of the United States that has never experienced a frost conditions. The warm water strongly modifies all cold fronts when they move in towards the city in winter from the north. The annual temperature range is quite narrow at around 7.9oC.
The average temperature in January is 21.3oC and the lowest temperature has rarely been below 10oC. The lowest temperature ever recorded was 5oC on January 13, 1981 and January 12, 1886. During summertime heating, the heat gets suppressed by the sea breezes and easterly tradewinds that prevail in this period. The average high and low temperatures during July are 31.9oC and 26.4oC. The hottest temperature in the records of Key West climate is 38oC in June, July, and August 1880.
Dry and wet seasons have characteristics of precipitation. The period between November and April receives rain at an average of less than 25% of the total annual rainfall in the city and most of the days are full of sunshine. This rainfall also occurs in a few light or heavy showers when cold fronts advance. The standard wet season is between May and October, with around 53% of the total annual rainfall. These rains occur through numerous thunderstorms and heavy showers.
Most of the days during this period experience rain, with the favorite raining time in the day being early morning. This is in total contrast to the mainland Florida, where the thunderstorms and showers occur normally during the afternoon. The tropical easterly waves occasionally cause excessive rainfall during this season. A few infrequent hurricanes could come with heavy amounts of rainfall. Still, Key West climate is considered to be uniform and mild, with Key West being the driest city in the state of Florida.
Hurricanes have hit Key West only very rarely. The residents of Key West mention Hurricane Wilma that arrived on October 24, 2005, as the worst storm in their memory. The authorities evacuated the entire city during that time. The storm flooded sixty percent of the Key West homes, with several areas of the island remaining under three feet of water. Thousands of cars got destroyed when the storm passed. Earlier, Hurricane Georges in September 1998 damaged several houseboats on the east side of Key West. Apart from such rare hurricanes, the Key West climate has been highly favorable to the residents as well as the visitors to this enchanting island.