I use Irish Spring bar soap mixed with just a bit of Got2Be glue and then an (un)healthy coat of Rave 4x hairspray. Adding a new coat of hair spray every few days my hair stays up for at least a week and a half....just don't get caught in the rain or your eyes will burn :)
Yeah the rain totally sucks. I heard there was some stuff called water-resistant Joico freeze spray or something that is supposed to work in the rain. Can't imagine how that would actually work. My mohawk is probably too long to survive the rain I'd guess.
However, there was this stuff in Montana called "Prime Time". They use it to spike the hair of cattle on auction blocks. I just tried it on a chunk of my hair one time and it was compressed elmers flying out of the can like a spider web. I stopped on the little bit though, cause my brother informed me the store that sells the antidote was closed and I was getting on a plane to San Diego early next morning.
Sadly the government confiscated my "Prime Time" as being too toxic to be carried even in stow-away luggage I guess, so I have not had a chance to try it again, with antidote (aka remover - which I suspect you really will need). Also, I'll bet your hair better be in place the first time, cause its gonna stick exactly like that, no teasing and pulling up into shape. I suggest a friend with a keen eye should you try this stuff.
Joico I believe makes the ICE glue as well...the stuff that you can only get from Salons in the blue bottle....I used to use it when I first started spiking my hair but it is expensive...like 10 dollars for a not so big tube of it. It was fairly water resistant but if you got caught in a hard rain it would crush your spiked hair.
Knox gelatin is quite waterproof after it solidifies. Messy as hell to apply and I never got the technique down for using it but when it dried my hair was SOLID and I would be in the shower for an hour trying to get it out. I have heard stories of people swimming underwater with mohawks and they would not be phased at all.
idk i used to use knox and it was fairly resistant to water it wasn't anywhere near totally and a mosh pit after 4 hours would usually need another half can of hairspray to put mine back in place since heat is what really kills knox