This mod requires the rageHookPlugin avaliable here : https://ragepluginhook.net/Downloads.aspx?Hook=1
To change this mod options just edit the c#Plugins\Hypoter.opt file within your read dead redemption 2 main folder (typically C:\Program Files\Rockstar Games\Red Dead Redemption 2)

The temperature lost by the body depends on environment temperature, wind speed and how much your wet (check the option file to tweak values)

Body Temperature	
From		To	State name
37°C		35°C	no hypotermia
35°C		32.2°C	light hypotermia
32.2°C		28°C	medium hypotermia
28°C		26°C	sever hypotermia
26°C			sudden death

State				Effect
no hypotermia		no effect
light hypotermia	just a msg to tell you that u feel cold
medium hypotermia	You dismount your horse every 30 seconds (cause u startin to not think right and you need to move your muscles)
sever hypotermia	You sometimes lose control and your character kinda freeze 
sudden death		instant death