Guides
Understand the number before you act on it.
Wet Bulb Globe Temperature (WBGT Index): a practical guide
Wet Bulb Globe Temperature—often searched for as the WBGT index—is a heat-stress measure designed for people who are active outdoors. It combines several parts of the environment that affect the body's ability to shed heat instead of describing air temperature alone.
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WBGT vs. heat index: which number should you use?
Heat index and WBGT both describe heat stress, but they answer different questions. Heat index communicates how hot warm, humid air feels in the shade. WBGT is designed to support decisions about exertion and exposure.
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Heat index vs. feels like: are they the same?
Heat index is one way to calculate a feels-like temperature, but the labels are not always interchangeable. A weather service or app may choose among heat index, wind chill or a proprietary apparent-temperature model depending on the conditions.
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Heat index chart: ranges, meaning and examples
A heat index chart combines air temperature and relative humidity to estimate how hot conditions feel to the human body. It is a screening tool for planning—not a guarantee that a particular person is safe.
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Running in hot weather: how to adjust the plan
Hot-weather running is a workload decision, not a test of toughness. Use conditions to choose the start time, then reduce pace or duration before heat strain forces the decision for you.
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Heat acclimatization: how gradual adaptation works
Heat acclimatization is the collection of adaptations that develops after repeated heat exposure. It can improve the body's ability to work in heat, but it reduces risk rather than eliminating it—and it should never be treated as permission to ignore symptoms or extreme conditions.
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Outdoor work heat safety: a planning checklist
A forecast can help schedule work, but it cannot replace a workplace heat program. Prevention combines environmental monitoring with workload, clothing, acclimatization, supervision and emergency response.
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Hiking in hot weather: plan for the return trip
A trail can become more exposed and difficult as the day heats up. The safest decision may be a shorter route, an earlier turnaround or no hike—even when the trailhead feels comfortable.
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UV index explained: what the number means
The UV index describes the strength of sunburn-producing ultraviolet radiation at a place and time. It is not a temperature scale: a cool, breezy or partly cloudy day can still have high UV.
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