TAFB and the NHC are in the same building, but the forecasters at each can occasionally disagree on various aspects of development for any disturbance -- just like you see some here disagree from time to time.
As for the first disturbance, the NHC TWO primarily focuses on one to two days out, whereas the TWD -- if it ever mentions development -- will usually only mention the conditions that could lead to development. The TWD is generally just a discussion of what is occurring and what the overall features might do, not so much a discussion of whether a tropical cyclone will develop. That's where the TWO comes in. It's got favorable upper-level conditions and warm waters ahead of it, as noted, but it's also the time of year that anything that moves into such a region needs to be watched. The NHC just doesn't think it'll happen within 2 days.
With the second disturbance, you see more of what the TWD is about and how it should complement the TWO. With most features overland with that disturbance and less organization than seen with Bret or Gert at this point, they aren't going to hammer home about it's chances in the TWD. Given those two prior storms, however, and the forcing provided by the tropical wave, the NHC has to watch it closely. Based off of persistence and climatology, they suggest something could get going once it mvoes out over water. It's purposefully vauge, though.
BTW, while we're talking about products here, just a friendly reminder to everyone on the board that if you are going to copy/paste NHC products into a post on the board, just do the parts that you need to accentuate your discussion, as RC did in the post I'm replying to. Please do not copy/paste the entire product; instead, use a link. Thanks!
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