26th Conference on Hurricanes and Tropical Meteorology

Wednesday, 5 May 2004: 10:15 AM
Verification of the OCSI Atlantic Hurricane Predictions Since 1985
Le Jardin Room (Deauville Beach Resort)
Jill F. Hasling, Weather Research Center, Houston, TX; and J. C. Freeman
Poster PDF (60.0 kB)
Weather Research Centerís Orbital Cyclone Strike Index [OCSI] has been used since 1985 to predict the section of the coast of North America that has the highest risk of a tropical cyclone landfall in any one hurricane season. The OCSI is dependent on the phase of the sunspot cycle which is taken as the proxy for the effect of the orbit of the sun about the center of gravity of the solar system. Recently is has been shown that this orbit of the sun is shared by the earth much like the orbit of the earth is shared by the moon.

The North American coast has been divided into seven sections; Mexico, Texas, Louisiana to Alabama, West Coast of Florida, East Coast of Florida, Georgia to North Carolina and Virginia to Maine. The OCSI prediction gives the section of the coast with the highest probability of experiencing a landfall from a tropical storm or hurricane. Over the past nineteen years, the prediction has verified 16 times.

In addition a secondary prediction of the number of tropical cyclones expected in the Atlantic basin in any year has been made, number of hurricanes, number of storm days and number of hurricane days. These results have been compared with the predictions made by Dr. William Gray each year. OCSI prediction and Dr. Grayís prediction where compared for the number of cyclones plus or minus 2 storms. The OCSI model was closer eight out of the 17 years from 1985 to 2001. Three of 17 years Dr. Gray was closer and three years were tied. Five of the 17 years both methods missed by 3 storms or more.

Supplementary URL: http://www.wxresearch.com/outlook/verification/ocsiver.htm