Make being wet matter, or reduce its occurrence.
Rain causes the 'wet' debuff', which can reduce stats. Yes, rain causes other things as well, like making sneaking work a better, but generally, and *most* frequently, you're just forced to travel around dripping. It lasts for a good long time as well, and it rains frequently enough that if you're doing any kind of adventuring you're debuffed. No matter how interesting the campfire drying you out is, when it rains almost every 15 minutes, you're not going to avoid being constantly wet, unless you're underground (sometimes) or inside (mostly when you're at home). There should be raincoats or waterproofing or some armor or clothing that resists you being wet if the default settings are 'rains almost all the time'. And before you ask, I used the custom settings to turn down harmful weather to 'rarely', and I'm still getting this constantly. I should be perpetually debuffed, even a little, just by being outside.