Temperature alone doesn't tell the whole story. Wet-bulb temperature combines heat and humidity to show how difficult it is for sweat to evaporate and cool your body.

Checking conditions… live
°C
Wet-bulb temperature

°C air temperature

% relative humidity

What to do: Loading live conditions…

Updating…
Heat index

An estimate based on air temperature and relative humidity. It indicates how hot it feels in the shade and does not include wind, direct sun or activity level.

Estimated WBGT

A simplified estimate of wet-bulb globe temperature (∼0.7 × wet-bulb + 0.3 × air temperature). This simplified estimate does not directly measure radiant heat and should not be treated as an occupational WBGT measurement.

Today — wet-bulb trend

Loading hourly forecast…

Next few days

Expected daily peak wet-bulb, shown by risk category.

Loading forecast…

Historical context

Daily peak wet-bulb over the past few months.

Loading archive data…

How this works

What is wet-bulb temperature?

Wet-bulb temperature combines air temperature and humidity. It estimates the lowest temperature air can cool to through evaporation alone, so it shows how hard it is for sweat to evaporate and carry heat away from the body.

Higher wet-bulb temperatures make it harder for the body to lose heat through evaporation. Risk also depends on activity, sun exposure, airflow, clothing and individual health. There is no single temperature at which heat becomes unsafe for everyone — risk rises gradually, and the “Extreme” band at 30 °C is a warning level, not a biological cutoff.

What is the heat index?

An estimate based on air temperature and relative humidity that approximates how hot it feels in the shade. It does not include wind, direct sunlight or how hard you are working.

Why is WBGT marked “estimated”?

WBGT (wet-bulb globe temperature) is the occupational heat-stress standard (ISO 7243). A real WBGT measurement needs a black globe thermometer to capture radiant heat from the sun and hot surfaces. We do not measure a globe, so we show an approximation (≈0.7 × wet-bulb + 0.3 × air temperature). This simplified estimate does not directly measure radiant heat and should not be treated as an occupational WBGT measurement.

What are the limitations?

All values here are environmental indicators computed from weather data, not measured at your exact location, and they are not individualized medical advice. Real heat risk depends on exposure duration, activity level, direct sunlight and radiant heat, airflow, clothing, acclimatization, age and underlying health conditions.

Methodology & data sources

Weather data
Open-Meteo open forecast data, refreshed automatically.
Selected location
Detecting…
Coordinates
Last updated
Wet-bulb temperature
Estimated from air temperature and relative humidity using the Stull (2011) regression (typical error ≈ 0.3 °C).
Heat index
Calculated from air temperature and relative humidity.
WBGT
Estimated only — an approximation using air temperature rather than a measured globe temperature. Not an official ISO 7243 measurement.
Historical archive
Daily peak wet-bulb for the selected location when open data is available.

This dashboard provides environmental heat indicators, not individualized medical advice.