Tropical Cyclones and Drought Amelioration in the Gulf and Southeastern Coastal United States

ASU Author/Contributor (non-ASU co-authors, if there are any, appear on document)
Peter T. Soule' Ph.D., Professor (Creator)
Appalachian State University (ASU )
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Abstract: Precipitation from land-falling tropical cyclones (TCs) has a significant hydroclimatic influence in the southeastern United States, particularly during drought years. The frequency with which TCs ended drought conditions was examined for southeastern coastal states from Texas to North Carolina during 1895–2011. The region was divided into the Gulf Coast states (GCS) and the southeastern Atlantic coast states (ACS). The spatiotemporal patterns of tropical cyclone drought busters (TCDBs) were analyzed. Larger-scale ocean–atmosphere influences on TCDBs were examined using chi-squared analysis. The ACS experienced TCDBs more frequently and farther inland compared to the GCS. The number of TCDBs has significantly increased with time in the ACS. TCDBs numbers in the GCS did not exhibit significant increases, but the area alleviated of drought conditions increased signi?cantly in the last 117 years. The dominant larger-scale ocean–atmosphere forcing of TCDBs was a combination of a warm Atlantic Ocean [positive Atlantic multidecadal oscillation index (AMO1)] and weak westerlies [negative North Atlantic Oscillation index (NAO2)]. AMO1 leads to an increase in the number of TCs throughout the North Atlantic basin, and NAO2 increases the likelihood of TC landfall by controlling the steering of TCs toward the southeastern United States.

Additional Information

P. T. Soulé, J. T. Maxwell, J. T. Ortegren and P. A. Knapp (2013) "Tropical Cyclones and Drought Amelioration in the Gulf and Southeastern Coastal United States" Journal of Climate Vol.26 Version of Record Available From ( (open access)
Language: English
Date: 2013
hurricanes, typhoons, hyrdometeorology, climate variability, North Atlantic Oscillation

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