From Jeff Masters on his blog:

Steering currents are expected to remain weak the next two days, and some erratic motion is possible. All of the forecast models predict a generally west or west-northwest motion over the next two days. However, this morning's southerly motion at 5 mph is something none of the forecast models have called for. This gives me some concern about this storm severely impacting Honduras and its neighboring Central American countries, particularly Guatemala, which is still reeling from the impact of Hurricane Stan. As Wilma grows in size, a continued southward motion may allow it to start pulling in a deep layer of moisture from the Pacific Ocean, which would trigger heavy rains over the regions of Guatemala and El Salvador hardest hit by Stan. These rains would probably be in the 3 - 5 inch range--nowhere near the devastating 15 - 25 inches seen from Stan, but still high enough to trigger new mudslides on the destabilized slopes of the steep mountainsides.

The computer models have been having huge difficulties with a weak trough of low pressure over the U.S. that may be able to pull Wilma northwards. Last night's 00Z (8pm) models runs of the five models we plot on our computer model tracking chart all failed to properly initialize this trough, calling for it to be weaker than is really is. This resulted in a set of model tracks with a much further west track for Wilma, bringing her into Belize or the Yucatan later in the week. This morning's 06Z (2am EDT) runs of the GFDL and GFS model did properly initialize this trough, and these new model runs now indicate a sharp turn to the northwest and north across western Cuba. Given that the models are not currently handling the southerly motion of the storm, I would be hesitant to believe this forecast yet. All the computer models were calling for a similar northward track for Hurricane Mitch in October 1998, and it ended up wandering south and getting stuck off of the coast of Honduras. However, a second much stronger low pressure system currrently bringing rain to southern California is expected to move east this week and push a trough far enough south to pull the storm northwards later in the week,