We've got the infamous marine layer here in SoCal, responsible for what's known as May Gray and June Gloom, and it affected my training out of John Wayne, which is quite near the coast. Fortunately, a lot of days the layer would provide a 1500' ceiling, so at least we could do VFR pattern work.
Good luck, and most importantly, have fun with your training. Like Arlen said, it is great training and will improve many aspects of your airmanship. As my picture shows, it also gives you some flexibility. Who knows how long I would have had to wait for the fog to burn off.
FWIW I highly recommend PIC and their 10 day program. I was skeptical about getting a rating in ten days but found the concentrated nature of it to be a huge plus. I got lucky and had about half the training occurring in actual IMC which did a lot to the confidence factor after I got the rating to actually go out and use it. That is was in my plane with the equipment I was going to be using was also huge bonus.
Downside: Time and money. But I figured it cost a lot less that way then dragging things out.