The merging of Wilma and the cold front is one part of it. Wilma's large wind field is also a part of it...and that is forecasted to expand as it meets up with the cold front which should just be near Tampa as Wilma makes landfall.
The last I heard on TV was that the hurricane force winds expanded out almost near to 70 miles; the TS winds expanded out almost 200. The good news is that the further out the Hurricane force winds are, the weaker the storm. If the eye tightens up again, it will be reintensifying. Which they are saying that's what it is supposed to do, but who knows at this point.
BayNews9 does a good job of explaining why we are supposed to get the windy and wet weather in the Tampa Bay viewing area. Maybe he can explain it better than I can.