TTs are inherently susceptible to strong gusting side winds. Towed our TT once with strong gusting winds and it was like driving on marbles and hard to stay in a straight line down the highway. Very white knuckle stuff.
A FW can get blown clear over. We spoke to a guy in a CG in Wa. once who regularly travels the I-90 between Spokane and Seattle where there can be strong winds. He said he has seen many FWs blown right over. FWs have a huge sail area compared to TTs and being much taller, makes them easier to blow over. You could be traveling happily down the road and then whammy. Even semi trucks can get blown over so don't assume your FW will be just fine.
If it does get really windy, pull over somewhere and wait it out whether you've got a TT or FW just like semi drivers do sometimes.