The 'red' Alfine 8 speed hubs had extra weather sealing, that's why it was great in the tornado weather lol.
TBH if you leave it in the rain just do a repack before you ride it again, unless it's a stupidly fancy hub, a lifetime bucket of grease suitable for hub bearings is probably still under 20-30 USD per person, and if you've got the wrenches and a stand [0] a repack can be done in 20 mins or less.
Edit: to be clear, I'm talking about normal hubs, with the Alfine we did an inspection but the seals looked good and a peek done inward indicated everything was fine so... yeah those red bands were gr8.
[0] - IDK if they still make it, but the Minoura FT-1 is... pretty good balance of quirks for the lack of dollars spent, both for truing and other wheel checks...
TBH if you leave it in the rain just do a repack before you ride it again, unless it's a stupidly fancy hub, a lifetime bucket of grease suitable for hub bearings is probably still under 20-30 USD per person, and if you've got the wrenches and a stand [0] a repack can be done in 20 mins or less.
Edit: to be clear, I'm talking about normal hubs, with the Alfine we did an inspection but the seals looked good and a peek done inward indicated everything was fine so... yeah those red bands were gr8.
[0] - IDK if they still make it, but the Minoura FT-1 is... pretty good balance of quirks for the lack of dollars spent, both for truing and other wheel checks...