This week and this past week have been quite warm, so if we don't get anymore cold fronts, I think you should be good to go on water rides and swimming in the pool.
I definitely know that last year (with the crazy cold temperatures that lasted F-O-R-E-V-E-R!) around March 7th, it was cold. So hopefully it won't be this year.
Missymj....I am going to be there the same time as you. Just an FYI...the weather channel and weather bug are both saying the weather is going to be sunny and in the 80's. Of course it could totally change since we still have a couple of weeks, but I'm hoping they are correct!! I will be monitoring the weather like a maniac! Keeping my fingers crossed that it's warm and sunny for us!!!