which cuts across the northern part of town. Much of Bartow is built on the Fort Meade soil series, which is well drained, high in organic matter, and rich in phosphorus, an uncommon combination in Florida, much appreciated by area gardeners. Climate Bartow, like most of Florida, is located in the humid subtropical zone (Köppen climate classification: Cfa). The climate of Bartow and other inland cities is slightly different than those cities on the coasts of Florida. Typically, the ocean or gulf tends to moderate the climate of cities on the coast. As Bartow is further from the coast than almost any other city in Florida, it tends to have higher daytime temperatures cooler temperatures at night. Regardless, the climate pattern prevalent throughout central Florida is evident in Bartow: hot, humid summers with frequent afternoon thunderstorms and relatively drier and milder winters. On average, a tropical system brings hurricane-force winds to the Polk County area less than once every ten years, although the 2004 hurricane season in which three hurricanes hit within 44 days was a case study in the law of averages. Until 2004, the most recent storm to bring hurricane-force winds to the Bartow area had been Hurricane Donna in 1960. While Florida's vulnerability to hurricanes is well known, hurricanes are not the most common severe weather threat seen in the Polk County area. The area is in the center of "lightning alley", the most concentrated lightning strike area in the United States. Lightning is not the only threat from central Florida thunderstorms. The more severe storms bring the threat of tornadoes, although Florida tornadoes very rarely reach the size of those elsewhere in the United States. Even hail is not out of the question; one storm in March 1996 caused a one-foot accumulation of hail in areas of Bartow. Freezes are an occasional occurrence in the Bartow area and can be a problem if temperatures remain below freezing for a sustained period of time. On average, the area can expect an annual minimum temperature of . Snow is a rare phenomenon in the area, perhaps a few times every century. Demographics As of the 2010 census, there were 17,298 people; 6,254 households; and 4,218 families residing in the city. The population density was 377.1 inhabitants per square mile of land (976.7/km2). There were 7,130 housing units at an average density of 155.4 per square mile of land(402.5/km2).