Here is how I made the "Hot Weather Idle" to play in Gray Cowl of Nocturnal, try it yourself:
First, Download EVG Conditional Idles from the Nexus and extract the files.
Second, Open the extracted folder and take out the mt_idle.hkx from " 03 Headache New" folder. (My Hot Weather Idle was based on EVG.)
Third, use that mt_idle.hkx for your Dynamic Animation Replacer mod with the below _condition.txt: (Experiment for yourself, there are no limits with DAR.)
CurrentWeather("Gray Fox Cowl.esm" | 0x000D73) AND
NOT IsInInterior() AND
NOT IsInCombat() AND
IsActorValuePercentageLessThan(26, 0.80)
ps: The idle will play when you are in the Alikr desert with less than 80% stamina.