Yeah...you definitely need a longer fetch to generate the streamers themselves...hence why Champlain needs a north wind or the very rare cold southerly wind. But it doesn’t take much of a body of water to enhance a system that’s already there. I’ve seen flurries flying in the air with clear skies down the hill along the Winnipesaukee River on very cold mornings near saturation. If you have a body of water that can produce decent radiation fog it’s going to create some moisture flux. I know there was some research from the LES crew I worked with in western NY that found there was even decent moisture flux on the Great Lakes with a mostly frozen surface. But the point is I agree...Champlain isn’t generating any precip on its own with those westerly components, but there will be some element of enhancement.
Do you guys notice heavier snows from them earlier in the season versus mid season when Champlain creates higher delta Ts?