Do regularly look at the Farmers Almanac predictions and compare them to what actually happens? I haven't myself. However, I do recall reading an article stating that their predictions are rarely accurate. If I recall correctly, the article said that they were accurate 11 times in the last 50 years.
I think that there is a romantic notion that people close to the land, such as farmers, can observe how many nuts a squirrel gathers and more accurately predict the weather than modern science. I don't think that there is actually any truth to it.