On a side note and in addition...the 18Z model of the GFS shows that TD 1 may never actually affect central america (landfall wise). Instread it may shunt off to the NW then W. Later, something else may possibly get going in the western Caribbean. Looks like the GFS has been trying to make the simplist solution for a complex weather picture in the medium to longer ranges. No true assurances that the next system will develop in the western Caribbean in 4-5 days either.

Link: http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/carib/gfs/18/index_pcp_l_loop.shtml