Finally going to replace my ancient 25-oz REI GTX shell, and I'm zeroing in on the GoLite Tumalo Trinity as the best balance of functionality/weight/price.
Since I can't try it on before I buy, my question is: will a size S fit over my size S Patagonia NanoPuff hoody? I expect to mostly wear it while hiking but would like it to fit over my insulated jacket for rainy evenings/mornings in camp.

