8
and pulpwood production, contribute substantially. Attracted in part by the availability of large dependable supplies of water, manufacturers of paper, rayon, and nylon are establishing many mills in the northern part of the State.
The State's mild climate has, of course, been predominantly instrumental to its agricultural development and to its popularity as a winter resort. Generally, the State is frost free more than 9 months of the year. With average temperatures of 81o F. in July and 590 F. in January, the climate is usually neither excessively hot nor excessively cold. Only once has a subzero temperature been recorded in the State: a low of -2o F. nipped Tallahassee during the unprecedented, nationwide cold wave of February 1899. The highest temperature on record is 1070 F., but yearly maxima of 100 F. and minima of 200 F. are by no means common anywhere in the State. Snow is so rare that many adult natives have never seen it.
The 1950 census recorded in Florida a permanent population of 2,770,000, which represents a growth of 46 percent since 1940. Part of the growth has come from an influx of elderly people, who are retiring and establishing permanent residence in the State.
PRECIPITATION
As shown in figure 1, no part of the State has been slighted in the distribution of rain. In the extreme southeastern and northwestern sections of the State the average is 64 inches and at other places is generally more than 48 inches. The average over the State as a whole is 53 inches a year.
Although there are well-defined wet seasons and occasional droughts, ordinarily the rainfall is fairly well distributed through the year. The seasonal distribution at Gainesville is typical of that at most stations (fig. 2). The period of greatest rainfall generally begins in June and ends in September but extends into October on the southeast coast, owing to the far-reaching influences of tropical disturbances in the Atlantic Ocean.
Long-term trends of rainfall at Gainesville are represented in figure 3. During the 50-year period from 1901 to 1950 the yearly rainfall averaged 50 inches but ranged from as little as 32 inches in 1917 to as much as 65 inches in 1941. From 1901 through 1918 the rainfall was generally less than average; from 1919 through 1943 it was about average; and from :1944 through 1950 it was generally higher than average.