Ditto the above. I assume you were careful with the hose, and didn't direct a jet of water into the bearings. Cartridge seals aren't that good.
RD jockey wheels are easy enough to clean out when you get a chance. If you have external cable housing, the important piece to check and service is the loop at the RD. I have a bike with the loop run up the seat stay rather than the chain stay, and I have more problems with that than anything else in the rain.
Sometime soon you may want to take wheels off the bike to check the hubs, maybe even remove the crankset to check the BB. You may get a different feel in the bearings without the mass.
And service your frame pump if you have one, before it's too late and you need it. Ask me how I know.