Based on 30 years of data collected by the National Climactic Data Center from 1971 through 2000, Hawaii, Florida, Louisiana and Texas have the warmest winter temperatures. This ranking is based on the mean temperatures for December, January and February for all 50 U.S. states as observed at weather stations across each state.
Hawaii, the only U.S. state never to have recorded a below-zero temperature, averages 67.4 degrees Fahrenheit from January through March. While temperate, this is still substantially cooler than the temperatures experienced during the summer months, which can reach the mid-90s. The rainy season runs through December, but January through March still averages 11 inches of precipitation a month. Substantial differences in climate exist, depending on your elevation; temperatures on the mountains can be much cooler.
Florida, the sunniest state on the East Coast, averages 59.4 degrees from January through March. It's the warmest mainland U.S. state. Winter daytime temperatures in southern Florida are typically in the mid-70s, with winter daytime temperatures in the low-70s in central Florida. Northern Florida is a bit colder, with winter daytime temperatures in the 50s. Both its southern location and the fact that it's a peninsula, surrounded on three sides by water, influences Florida's climate.
Louisiana averages 50.9 degrees from January through March. Northern and southern Louisiana experience very different climates, however. Southern Louisiana, where the Gulf of Mexico moderates the climate, has an average temperature of 54 degrees in January, while northern Louisiana's average is 49 degrees. Northern Louisiana can experience frosts from mid-October through March; some areas of southern Louisiana do not experience a frost all winter.
Texas averages 47.9 degrees from January through March. San Antonio, Texas, holds the record for the highest winter temperature ever recorded in the 40 largest cities in the U.S. at 100 degrees, although San Antonio's average winter temperature is much lower, at 52.5 degrees. While not common, Texas does occasionally experience blizzards, heavy snow, freezing rain, ice and freezing temperatures.