Tropical Cyclones

1. Tropical cyclones pose a threat to the Pensacola area throughout the Atlantic Hurricane Season (01 June-30 November). The principal threat to Pensacola is from tropical cyclones approaching from the southeast, south, and southwest. Seventy-three percent of all tropical cyclones reaching a distance of within 180 nm of Pensacola between the years 1871 and 1979 have approached from these sectors. Pensacola's location within a hurricane belt and the absence of sheltered facilities and anchorages available to deep-draft vessels in Pensacola Bay make it a poor hurricane haven.

2. The dominant features of the Gulf Coast region is its location on the northern shore of the Gulf, and its east-west orientation, which is perpendicular to the usual tropical cyclone tracks at this latitude. The region between 25( N and 35( N is particularly important in that it lies within the normal point of convergence for recurving tropical cyclones. This is significant because tropical cyclones typically slow and intensify during the recurvature stage. During the recurvature stage of the tropical cyclone life cycle, it is more difficult to accurately predict the rate of recurvature, the storm speed after recurvature, and the storm's precise future position.

3. During the 109-year period between 1871 and 1979, there were 143 tropical cyclones that met the 180-nm criteria for Pensacola. This translates into an average of 1.3 per year. The following table shows specific monthly totals and percentages.

Month Number % of Total
June 18 12.6
July 16 11.2
August 22 15.4
September 56 39.2
October 27 18.9
November 2 1.4

The major threat sector extends from southeast to southwest. It should be noted that six tropical cyclones have developed within 180 nm of Pensacola, and were at their closest point of approach (CPA) at the time of formation. An approach direction is therefore not applicable to these storms. Two of these six developed into hurricanes very quickly.
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