look at the fat chick that punched the old guy Trump supporter in the face. She didn't go down like she was shot
I bet that wasn't FOX spray. I've seen videos of grown men screaming from it. In heavy rain, I could see raindrops affecting the stream, but you have a good 7 seconds or so from 4oz, with 21 feet of range with the stream type. To back up the spray, I have a "Policeforce" brand 80 lumen ink kubaton. Taser would probably be too much to carry.
Gel/foam is to be avoided - Ask any prison guard - your attacker will throw a handful right back at you.
Fog type? No thanks, wind puts it right in your face, lack of range, and makes indoors uninhabitable temporarily and would get you in more trouble for gassing out a building.
The target is the eyes, which I doubt rain would do much for. If you don't hit the eyes, you're not going to disable him most likely.
In the purse or in a pack is not good enough, and not safe. I keep mine in an ultrafire flashlight holster, on the bottom of my EDC pack, or sometimes in my jacket pocket, left side, right side reserved for lethal force. For motorcycle riding, these are the two spots that keep it protected, so you don't fall on it and break bones and explode a cannister of OC while crashing. So I reach around with my left hand behind my back, leaves it pretty concealed and gives me a quick and sneaky option. The holster also prevents accidental discharge. I think FOX has the best design with the flip top, and apparently is the strongest in the world @ 5.7 million scoville heat units.