4. Fourth Designator; Tidal Range 
L: Less than 10 feet 
H: 10 feet or greater 
5. Fifth Designator: N: Area not affected by river (fresh 
water) discharge. 
R: Area affected by river (fresh water) 
discharge. 
An example of the use of the CLASSIFICATION INDEX is given 
for Los Angeles. The coldest mean monthly air temperature (See 
Figures 1 to 12) is 55° in January. The warmest mean monthly air 
temperature is 68°F. in July. The tide range as shown by Figure 13 
is less than 10 feet. Available maps show that no fresh water discharge 
affects this area, The 13°F. temperature difference between 68°F. and 
55°F. places this location in the Oceanic Climate Class. The coded 
designation of this area, 5568OLN, identifies the harbor class. With 
the mean air-water temperature difference (See Table II ) for an OLN 
class andthe typical winter and summer vertical temperature differences 
from the surface temperature (See Table VI) for OLN class, an estimate 
of the surface water temperature (T_ or T__)is possible as well as an 
estimate of the 68% confidence interval rough use of the standard 
deviation values from the means. Although information in the tables is 
compiled only for the warmest and coldest months, a suggested method 
of estimation of temperatures at the surface and depth for intermediate 
months is shown under PREDICTION EXAMPLE. It shouldbe noted that 
the surface water temperature (T_ or T__) derived from Tables I to 
IV refers to the surface water very nearshore; whereas, the vertical 
differences are with respect to the surface water temperature (Tw 0) 
above the 30-fathom isobath. The surface water temperature above five 
30-fathom isobath (Tw...) can be estimated by adding the correction (C) 
in Tables IX to XII to “he nearshore surface water temperature (T_ or 
Ta) an 
ms 
Since the C values in Tables IX to XIII do not present values for 
distances greater than 10 nautical miles from the shore, the C value 
at 10 nautical miles should be used to obtain (Tw) when the 30 fathom 
isobath is more than 10 miles offshore. 
