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Zeta's center appears to be partially embedded in the central dense
overcast and Dvorak T-numbers from TAFB and SAB are 3.5...
corresponding to a 55-kt current intensity estimate.  An ssmis
image at 1116z depicted an eye-like ring...although this feature
appeared to be at mid-levels and displaced northeast of the
low-level center.  Upper-level outflow is fairly well defined over
the northern semicircle of the storm...and so far the strong winds
in the upper-tropospheric environment have not had much of a
disruptive influence.  An upper-level trough...that is currently
nearing Zeta...is predicted by the global models to split and this
could briefly create a more favorable environment for strengthening
today.  The official forecast will show no weakening until a little
later in the period...when strong upper-level northwesterlies in
the wake of the trough are expected to begin taking their toll on
Zeta.

Even with visible images...the center location is not that obvious
and the initial motion estimate is a somewhat uncertain 250/4.  A
mainly westward track...to the south of a low-level ridge...is
likely for the next day or so.  Thereafter a large low moving from
the western Atlantic is forecast to turn Zeta to the right.  The
official forecast follows this reasoning and is to the right of the
model consensus and leans toward the GFDL track.

 
Forecaster Pasch