Heat stress, explained.
Plain-language guides to the numbers that actually measure heat danger, and what to do when it climbs.
What is wet-bulb globe temperature (WBGT)?
The complete heat-stress measure: how it's built, how to read the danger levels, and why it's the standard.
WBGT vs. heat index: what's the difference?
Heat index is shade-only; WBGT adds wind and sun. Which to trust, and when.
What is a WBGT forecast, and how far ahead can it be trusted?
Heat stress predicted, not temperature. How it's computed, how far ahead it holds, and what an on-site reading still governs.
How accurate is this WBGT, and how do we know?
A live WBGT is a model. How we check ours against the NWS, find the conditions it runs warm or cool, and correct it: checked on days it never saw.
Is it too hot to walk my dog?
The air temperature isn't the number that matters: the ground is. What burns paws, and when.
Why pavement stays hot after sunset
The air cools at sunset; the ground doesn't. Why evening walks catch people out.
Why 87 °F can be more dangerous than 105 °F
A humid 87° can be harder than a dry 105°. Why humidity, not heat, decides.
Acclimatization: why the first hot week is the most dangerous
The hottest day isn't the most dangerous: the first hot week is. What adapts, and how fast.
Football linemen and heat stroke: why exertion matters
The same WBGT is a heavier load for a lineman in a conditioning drill. What an NFHS task force found, and where exertion fits in the app.