PREDICTION EXAMPLE 
The following steps show how a forecast of water temperature is 
made for a harbor near New Orleans at the mouth of the Mississippi 
River. 
STEP I 
List the mean air temperature in this area by months from Figures 
1 through 12 or from ‘‘U. S. Navy Marine Climatic Atlas of the World."' 
Estimate the air temperature to nearest 0.1°F. 
MONTH MEAN AIR TEMPERATURE (°F.) 
Jan 60.0 
Feb 60.0 
Mar 64.0 
Apr 69.8 
May 72.5 
Jun 81.8 
Jul 82.0 
Aug 83.2 
Sep 82.5 
Oct 77.0 
Nov 68.0 
Dec 63.0 
STEP I 
Note the coldest month (January and February) to the nearest 
degree and assign the First Designator from the Classification Index. 
(60) 
STEP Ill 
Note the warmest month (August) to the nearest degree and assign 
the Second Designator from the Classification Index. (83) 
STEP IV 
Subtract the First Designator value from the value of the Second 
Designator to determine the Third Designator from the CLASSIFICATION 
INDEX. (23) This places the harbor in the Sub-Continental category 
