Drying comp rubs

I'd like to know this one too! I always have clumpy rubs from the humidity.

This is why I buy in bulk and vacuum seal what I won't be using right away

I would take one of those silica packs you find in jerky and put one in the jar to see if it will help take the moisture out.

You can do this but your quality will decrease with the release of oils and such through heating of the spices.

I have used a "brown sugar bear" in my rubs with some pretty good success. Instead of soaking, I leave em dry and they control the moisture pretty good over the winter when I am not using as much rub.
You can find em on Amazon or with other kitchen gadgets at target or Walmart.

Assuming this problem is from leaving them in the trailer, as that is where I have the problem too. I now put two layers of saran wrap over the top before screwing the lid on. This has helped alot, but still thinking of getting a plastic tool box or such to carry in and out before each contest.

This is a huge problem for teams down here in Houston. Rubs will clump on me if I keep them in my pantry inside my air conditioned house. I've started putting all my normal sized rub shakers inside a 2 gallon ziploc, and then throwing in a couple silica packets. Then for my bigger containers and bulk bags, I put a silica packet inside each one.

I have found though, that there seem to be two different ways that they clump up. Brown sugar, and things with brown sugar seem to clump up when the molasses doesn't have enough moisture. The molasses dries out and starts clumping together I guess? For things that dry out even when I put silica packets, I've started throwing half a slice of white bread in, and have had good results.

These are the silica packets I use - [ame="https://www.amazon.com/Gram-Silica-Packets-Desiccant-Dehumidifiers/dp/B00DYKTS9C"]Amazon.com: 5 Gram Pack of 50 "Dry&dry" Silica Gel Packets Desiccant Dehumidifiers: Home & Kitchen[/ame]

I keep all my rubs, brown sugar, honey, etc. in an airtight storage tote that gets easily moved between downstairs pantry and trailer for comps. I really like it. Easy to haul around, keeps all the rubs organized and in one place, and it fits standard sized shakers and quart sized jars perfectly.

[ame="https://www.amazon.com/MTM-ACR8-72-Crate-Utility-Large/dp/B01L3ZN78M"]Amazon.com: MTM ACR8-72 Ammo Crate Utility Box with 7.25" Deep, Large, Dark Earth: Sports & Outdoors[/ame]