Rain can flush out nutrients, especially when you add a lot of dirt to your compost.. But on the other hand you need moisture for composting. I wouldn't worry to much about it. I always dig a pit, put greens, pig manure and weeds in it and cover it up again, but I don't use it for peppers (I wait 2 years and plant a fruit tree in the pit).
Rain can flush out nutrients, especially when you add a lot of dirt to your compost.. But on the other hand you need moisture for composting. I wouldn't worry to much about it. I always dig a pit, put greens, pig manure and weeds in it and cover it up again, but I don't use it for peppers (I wait 2 years and plant a fruit tree in the pit).