I have a flow chart for rain gear.

Is it going to be heavy ongoing rain? If yes, do I really need to go in the first place? If yes, I look at the temperature and purpose. If on a search bushwacking and in the rain, I take a rain jacket and pants, with ventilation zippers. I don't plan to keep them in one piece or even necessarily stay dry. I will be sweating and miserable either way. But, perhaps my clothing will not be torn to shreds by the whitethorn.

Is it a good chance there will be rain for a significant part of the trip? If so, I take a poncho and rain pants. I might take the umbrella if it's not so stormy it'll blow me away.

Is it going to be a slight to no chance of rain? If so, I take an emergency poncho instead of the heavier PU coated poncho.

Is it going to be cold, like within 10 or so degrees of freezing, with a slight to moderate chance of precipitation but not necessarily rain? I take a jacket and rain pants, but not the same ones I take on a search.... The more expensive, breathable (we pretend they are anyway) ones.

Sometimes when it rains, I don't put on rain gear at all, because there is enough sun and time left in the day to dry and it's just a summer afternoon shower in the Sierra.

Sometimes it's obviously here to stay for hours, and it's getting colder. So on it goes, pit zips open if it's a jacket, and I have a dry change of base layer in the pack for when I set up camp, because it's not like I pretend that I'll stay dry - just more dry than I would have been without the rain gear, and moderately warmer.