Although my gear is inside an observatory the humidity can still get close to 100%, so I use a waterproof cover like a large sock that slips over from the top and pulls in tight with a draw-string around the pier. I put a few silica gel containers inside as well.
I am also going to make a simple humidity meter using one of
these so that I can remotely monitor the moisture level especially when the gear is left for long periods (no doubt caused by excessive cloud cover). I'll post some details when I get it going.
Chris