105 F + 15% Humidity, Desert Dry Heat
Audience: Tourists, runners, hikers in arid regions
Air Temp
105°F
41°C
Humidity
15%
Heat Index
100°F
38°C
Risk band
Extreme Caution
What this means
Dry heat actually reads lower than the actual temperature on the NWS chart because sweat evaporates quickly. But dehydration risk is severe, you stop noticing you are sweating.
What to do
Drink water before you feel thirsty. One liter per hour during sustained activity. Phoenix, Las Vegas, Tucson default to this range in summer afternoons.
Source
NWS Heat Index, Dry Climate NotesOther Extreme Caution scenarios
Not medical advice. The NWS Steadman heat index is a general guideline; individual heat tolerance varies with acclimatization, medications, and pre-existing conditions. Consult a medical professional for individual risk assessment.