Annette. If you want to know about rain, I am the rain guru!!! :-D I live in southwestern British Columbia, about 45 km from the coast. Southwestern British Columbia is known as a rain forest. Yes, we have lots of rain, wind, cool, winters. Sometimes in January we can have freezing for a couple of weeks straight. We can have frost as early as October 15 (like last year), it is frosty off and on definitely after the end of October. The frost comes with clear skies. We have lots of overcast skies with rain, which removes the chance of frost. We don't get very often snow, it may snow now and then, but this is not typical of our rainforest weather.
I can tell you that for the two seasons that I have been keeping bees, I have not had any issues of rain getting into the slot on the inner cover. It is a small slot, about 1 inch wide, and of course, not much taller than a "bee space". THis slot in the inner cover is integral to keeping moisture out. We were taught that in our beekeeping courses. Very, very important. Should the slot in the inner cover not be there, then there is no way for moisture to escape the hives in the wintertime.
My bees use the bottom and top entrances and happily guard both.
Now KathyP is a different matter. I remember she spoke about the issues she had with the wind blowing the rain into her hives. She had extentuating circumstances at her property, I think she has weird winds that come through her place or something. I can't recall the exact issues, but I remember she remedied the situation by one way or another. Maybe she will have input into this thread and give her opinion. Wait and see. But...got with the top entrance, you will see it will be OK. Don't worry Annette, you are doing wonderful. I know your concerns. I was a new beekeeper and had so many questions. I only found this forum last fall, had I found it quite some time before my beekeeping learning would have been so much simpler. Instead, I delved into books, took courses, read and read and read some more. I would not turn back the hands of time though, because all the books I read certainly have done nothing but good. But I did not have a mentor, like I said, this forum....it has been the best mentor on earth. And rely on Michael Bush's website, it is invaluable!!!!! Have this wonderful day and beautiful life and health to boot. Cindi