daily low tide height can actually exceed NGVD 3 percent of the time or 
11 days out of the year. 
Water Characteristics 
101. The results of daily measurements of surface water temperature, 
visibility, and density are presented in this section. The summaries repre- 
sent single observations made near 0700 EST and, therefore, may not reflect 
daily average conditions since such characteristics can change rapidly within 
a 24-hr period. A discussion of 1982 data is followed by a comparison to that 
of previous years. 
Water temperature 
102. Present data year. Daily sea surface water temperatures at the 
seaward end of the FRF pier (Table 15 and Figure 29) experienced large varia- 
tions in June, July, and August when frequent offshore winds blew warm surface 
water seaward, allowing upward and landward circulation of much colder and 
more turbid bottom water. Onshore winds reversed this circulation, piling up 
warm surface water against the shoreline, with a resulting seaward flow along 
the bottom. 
103. From January through March (Figure 29), monthly mean water temper- 
atures averaged less than 10° C and increased about 5° C per month from March 
through June. These mean values remained nearly constant and greater than 
15° C from July through October. During the remaining two months of 1982, 
temperatures decreased at about the same rate as the spring increase, i.e., 
5° C per month. 
104. The annual average water temperature during the year was eo C. 
with a standard deviation of 1.9° C. Less than 1 percent of the time (3 days) 
during the year the temperature exceeded a (Figure 30). 
105. 1982 versus previous years. Daily temperature variations were 
typical of those during other years. Due to a mild summer and winter, 1982, 
as a whole, was a moderate year in comparison to previous years; fewer 
occurrences of temperatures above 20° C and below 5° C were observed 
(Figure 30). Differences during the summer season were, in part, due to the 
frequent onshore winds and high wave activity during September, 1981, which 
tended to keep the water warm. The period during October to December 1982 was 
the warmest of all periods during the 3 years of data collection (Figure 31), 
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