Gulf Coast Deep Water Port Facilities study. Appendix B. North Central Gulf Hydrobiological Zones.

The single region under consideration is the North Central Region of the Gulf of Mexico, consisting of the coastal areas of Louisiana, Mississippi, and Alabama, and the adjacent offshore waters to a depth of approximately 25-30 fathoms. The climate of the coastal area of this region is strongly influenced by the Gulf of Mexico and its sub-tropical latitude. Summers are characterized by prevailing southerly winds which provide moist, semi-tropical weather. During winter, the area is subjected alternately to tropical air and cold continental air typified by large and sudden drops in temperature. Along coastal Louisiana, the average maximum air temperature in January ranges from 62 degrees to 68 degrees F, and maximum air temperature in July ranges from 74 degrees to 90 degrees f. Average rainfall along coastal Louisiana is 60.32 inches per year. Similar conditions prevail along coastal Mississippi with some freezing weather always occurring during the year. Rainfall ranges from 34.5 to 90 inches per year, and averages 59.9. The average annual temperature at Mobile, Alabama was 68 degrees F during a 59-year period. Summer and winter temperatures averaged 81 degrees and 53 degrees F. Rainfall at Mobile averages about 62 inches per year. As discussed later, offshore water temperatures also have great annual fluctuations. Meteorological features of the coastal areas of the three states under consideration are adequately covered in their respective Gulf Estuarine Inventories.