It is very different. Heat transfer in fluids is dependent on a number of things, but a big one being the flow rate across the surface. Your hose cranks out probably something like 3-4 gallons per minute. The falling rain in an average shower and subsequent spray off the road is probably more like a couple of cups an hour.Rbeane60 said:Shouldn't be any different than if it starts raining on you in the middle of the ride.
Never spray a hot motor or exhaust with cold water. I always like to have my engined warm just to the point where it isn't too hot to touch.