If its blowing a gale there is no way that you would wanna be towing a largish boat on the freeway with a sedan...and if you think you can pull a 6.0M boat out of the water with a rear wheel drive then you kidding yourself. Sure you will pull it out sometimes, maybe most of the time, but you wont pull it out all of the time. I know someone who has used a 5.0L premier, he had to push the car up the ramp with his boat. He obviously had some peices taken out of his prop from hitting the ramp on the way out...
For safety reasons and for peace of mind i would suggest you trade your car in for a 4WD...and i dont mean a big shopping trolley either....by saying a big shopping trolley I'm refering to the CRV, RAV4, Pathfinder, Pajero etc....look at getting yourself a Landcruiser, Patrol, Explorer, maverick, or Landrover....
Might be a hassle, or something that you dont want to hear...but its better to be safe than sorry..