Dew Point thresholds. Posting this to save it.

 

Comfort Thresholds by Dew Point

Meteorologists and health experts use specific dew point ranges to categorize comfort levels. These thresholds remain consistent regardless of the outside temperature. 

Dew Point Range	Comfort Level	Physical Sensation
Below 50°F (10°C)	Dry / Comfortable	Air feels crisp; sweat evaporates instantly.  Very low dew points (<40°F) may feel harsh or dry out skin.
50°F – 55°F (10–13°C)	Pleasant	Ideal for most people; moisture is barely noticeable.
55°F – 60°F (13–16°C)	Noticeable	Air begins to feel slightly humid; "sticky" evenings may occur.
60°F – 65°F (16–18°C)	Muggy / Uncomfortable	Distinctly humid; sweat evaporation slows; physical activity feels more strenuous.
65°F – 70°F (18–21°C)	Oppressive	Very muggy; air feels heavy; significant difficulty cooling down.
Above 70°F (21°C)	Tropical / Dangerous	Extremely oppressive; sweat barely evaporates; high risk of heat stress during exertion.