|Historical Hurricane tracks centered in the "Eastern|
Caribbean Graveyard." Credit: NOAA
So what causes the Graveyard to exist? Well, you can read the research above for a lot of good examples and details. Shieh's research found that one of the more permanent features in the Caribbean is the Caribbean Low Level Jet. It's an enhanced area of lower level winds (about 3,000 feet up or so) that's oriented primarily in the Central Caribbean during the summer, peaking in intensity in July. It's considered almost a semi-permanent feature of this region, meaning it's there almost all the time. Because winds converge there, there has to be compensation nearby, and winds actually diverge in the Eastern Caribbean, creating subsidence (or sinking air) that suppresses clouds and convection. Storms in the Eastern Caribbean are more likely later in hurricane season, as this effect dwindles. During El Niño events, this effect can be enhanced somewhat, though that research and linkage is still very limited.
|Tropical Depression 5 Official Forecast Wednesday Evening|