ecological characterization atlas of coastal alabama - Data Center

Simpson and Lawrence ( 1971) estimated the probability of tropical storms,
hurricanes, and major hurricanes for the 80 km (50 mi) coastline between
Bi 1 oxi , Mi ssi ssi ppi , and Mobi 1 e, Al abama . They predict an annual probabi l i ty
of 13% for a tropical storm, 6% for a hurricane, and 1% for a major hurricane
striking the area .
The U .S . Army Corps of Engineers, on the basis of previous records, have
predicted the probable recurrence interval for storm tides in coastal Alabama
(Table 33) . At Dauphin Island, for example, an 11 .5-ft tide would be
expected once every 100 years . These tides could occur in any year of the
time period or not occur at al l . The predicted maximum height could al so be
exceeded, as during Hurricanes Camille and Fredric (Chermock 1976) .
Winds within hurricanes, like tornadoes, travel counterclockwise in the
northern hemisphere . Winds are most intense near the center (eye) of the
storm, although the eye itself is fairly calm . As the hurricane moves
forward, winds are highest on the right side and weakest on the left . The
Table 33 . Probable recurrence interval for storm tides in coastal
(Chermock 1976) .
Alabama
Elevation above mean water level (ft)
Location
1 Year 10 Years 20 Years 50 Years 100 Years
Coastal Area-Fort
Morgan to Gul f Shores
(Pensacola quad)
Bayou St . John Area
(Pensacola quad)
Perdi do and Wol f
Bay Area
(Pensacola quad)
Grand Bay and
Bayou La Batre
(Biloxi quad)
Dauphin Island
(Biloxi quad)
Mobile Bay
(Mobile quad)
3 .6 7 .0 8 .3 10 .2 11 .4
3 .0 5 .0 6 .2 7 .2 8 .5
2.6 3.9 4.7 5.7 6 .5
3 .6 6 .8 8 .8 11 .4 13 .2
3 .6 5 .8 7 .6 9 .8 11 .5
3 .6 5 .8 7 .5 9 .4 10 .6
137