Warm water, hot climate, upper level wind movement, and wind shear all have to be run thru the complex computer models...LJ current wind shear... http://tropic.ssec.wisc.edu/real-time/windmain.php?&basin=atlantic&sat=wg8&prod=shr&zoom=&time= upper level winds... http://tropic.ssec.wisc.edu/real-time/windmain.php?&basin=atlantic&sat=wg8&prod=wvir&zoom=&time=