Rain, rain go Away

One thing I really worry about is my ability to train pre-ride. We did the Oregon Bicycle Ride about eight years ago, which is a week long bike tour, but we spent the entire summer training for that ride. Right now I'm busy, I'm a graduating senior, and I'm not willing to spend all my free time training. I'm getting in about two 15-25 mile rides per week (I'm planning to up the mileage soon), so hopefully that will give me enough of a base to work off of. I think the first week will just be painful, it's inevitable. However, days like Saturday and today are really throwing me off. It is pouring out, and as I lack both rain jacket and fenders riding is not pleasant. I got up and went for 15 Saturday, today I called me friends who ride with me and didn't even get out of bed. How am I supposed to motivate myself to train more when the weather is so discouraging? This is the rain we should have had all winter (we had an oddly dry winter) so that when spring rolls around and we want to be outside it's sunny and warm.