The annual range of temperatures in south Florida and the Everglades is rather small (less than 20 °F [11 °C]) – ranging from a monthly mean temperature of around in January to in July. High temperatures in the hot and wet season (summer) typically exceed across inland south Florida (although coastal locations are cooled by winds from the Gulf of Mexico and the Atlantic Ocean), while high temperatures in the dry winter season average from . Frost and freeze is rare across south Florida and the Everglades; annually coastal cities like Miami and Naples report zero days with frost, although a few times each decade low temperatures may fall between across South Florida. The plant hardiness zones are 10a north with an average annual extreme minimum air temperature of 30 to 35 °F (−1 to +2 °C), and 10b south with an average annual extreme minimum air temperature of 35 to 40 °F (2 to 4 °C). Annual rainfall averages approximately , with the Eastern Coastal Ridge receiving the majority of precipitation and the area surrounding Lake Okeechobee receiving about .