I took a look at NHC's position and the CIMMS Wnd Shear Analysis; at 31/2345Z the position of 13.5N 53.0W is directly under the 200/300 mb Upper Ridge. As you move west along the upper ridge axis located along 14N latitude winds are 15 knots from the south and along 16N latitude winds aloft increase to near 30 knots from the southwest. A wind surge may be construed as a gust front; outflow boundary from thunderstorms. Overland we have what are called gravity waves...rapid pressure falls creating gradience behind convective complexes which make for some very strong wind conditions followed by rapid pressure increases and winds return to calm/normal. Someone who is more versed with tropical weather may know more about this phenomena than I. This is a broad area and I wouldn't be surprised like Tip mentioned multiple surface & mid-level vortices...a big mess; I agree. In regards to the north bias the models are running it may be in response to the deeping east coast USA longwave trough in the days ahead. There's simply no way to know in the here and now how much amplification there will be of this trough into the tropics.