In the face of oppressive 35kt vertical shear, Nana has been written off... only a low-level swirl remains near 18N 44W.
On the other hand, what became TD15 yesterday has been upgraded to TS Omar, and the latest intensity estimate is 35kts and 1001mb. It's basically stationary (still sitting between Dominican Republic and Aruba), and getting better organized by the hour. Outflow is healthy, and a large area of cloud tops over the center are persistently -80C and colder. This could become the season's 7th hurricane within a day or so -- it has the visual appearance of a storm that's on the verge of rapid intensification. The stagnant motion won't be a big problem as far as the ocean is concerned... the heat content is extremely high in the Caribbean, so there's not really any cool water to be upwelled! The forecast calls for the motion to pick up in a day, and begin heading NE toward a weakness in the subtropical ridge. In 1-2 days, this will threaten Puerto Rico and the Virgin Islands.
In addition, the area of disturbed weather off the Nicaraguan coast that I mentioned in yesterday's update was upgraded to TD16, and appears to be on its way to becoming TS Paloma within a day. It too is over very water water with exceptional heat content, but a limiting factor in its intensification COULD be the proximity to land. The official forecast takes it from its current position near the "corner" of Nicaragua/Honduras and tracks it west along the coast of Honduras into Belize in three days. If it does manage to keep a bit further offshore and intensify notably, this could be really bad news for Honduras, which suffered greatly from a stalled major hurricane 10 years ago... Mitch.
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