Haven't worked a ton in the rain but between that and other activities I have learned that loose fitting clothing including shoes works best to stay comfortable in most or all conditions. Keep in mind the abuse they get, you might spend big and they get ripped or ruined prematurely. Loose ends can get caught in equipment , so try to avoid that . I had an 346 xp suck the drawstring of my jacket, into the flywheel, tried to eat me and did brake a fin on the 346. I like loose fitting water proof wind breakers with lesser amounts of insulation over shirts that don't retain moisture like a sponge, wool and the old acrylics have been my favorites. A light cotton- pollyester undershirt might be more comfortable under all. Use layers and carry extra so you can change out wet clothing.
I believe gortex has been the standard of breathable waterproof clothing , probably an outer jacket fully waterproof of some sort you could need for extreme rain conditions. I generally wear chaps over most any pants. Takes a while to soak the pants under chaps.
Seldom is it necessary for me to continue in extremes or I can sit it out inside until it breaks so others I am sure have some better advice for long term clothes under those conditions.
