I live in Florida where the humidity is high year round. I have never had a problem with a clogged auger but i think what can happen is the sawdust can harden if water gets in the hopper due to rain. I have a sifter and I use it from time to time but I use it mostly on abused bags of pellets. Sometimes I get a bag with little or no saw dust and just pour the whole bag in. Other times I get a bag that seems like it has been tossed around the store for 6 months and the sawdust will be very bad. That's really the only time I sift. Or when I make a 50/50 blend of charcoal pellets and something else. I'll load the sifter with charcoal pellets, dump it in a bucket then do the same with competition blend and repeat until the bucket is full.