WPBWeather wrote: But isn't that just a picture of the sheer, and not a movie? Sheer can change from day to day--so persistence is not forever
Sure, things can change absolutely. But, during El Nino, generally the North Atlantic basin is not conducive to development across the MDR and the Caribbean.
Now, there may be times when we see shear relax enough to allow conditions to become marginally conducive in some areas of the basin away from the MDR such as GOM and off the SE U.S. coast. Overall, I am anticpating shear to be mostly hostile this season, which will really put the whammy on systems trying to develop across the MDR. This is why the odds for the potential for homegrown systems are rather good for this season.