Dew Point
Calculator
Results
- Dew point (°C)
- 16.684249
- Dew point (°F)
- 62.031649
- Dew point depression (°C)
- 8.31575
Weather results
| Dew point (°C) | 16.684249 |
| Dew point (°F) | 62.031649 |
| Dew point depression (°C) | 8.31575 |
formula-map diagram
- Dew point (°C)
- 16.684249
- Dew point (°F)
- 62.031649
- Dew point depression (°C)
- 8.31575
Weather relationship
Formula
Td = b×γ ÷ (a − γ), γ = a×T÷(b+T) + ln(RH÷100), a = 17.27, b = 237.7 °C= 16.684249595499
Note
This is a simplified model: it applies the published standard formula to the numbers you entered and ignores local terrain, radiation, precipitation type and instrument error. Wind chill is the 2001 NWS/Environment Canada regression, valid at or below 10 °C with wind at or above 4.8 km/h; the heat index is the Rothfusz regression, reliable above about 27 °C; dew point uses the Magnus approximation (a = 17.27, b = 237.7 °C) over liquid water; wet bulb uses Stull's approximation at standard sea-level pressure; pressure and density altitude assume the International Standard Atmosphere and dry air. Do not use these results for aviation, structural or safety decisions without an official forecast or a qualified professional.
More in Weather and climate
See all →Frequently asked questions
What is the dew point, in plain terms?+
The dew point is the temperature air would need to cool to (at constant pressure and moisture content) for it to become saturated and start condensing water as dew, fog, or frost. It's a direct measure of how much moisture the air is actually holding.
Why is dew point considered a better humidity indicator than relative humidity for comfort?+
Relative humidity depends on both moisture content and temperature, so the same relative humidity reading can feel very different at different temperatures. Dew point measures absolute moisture content directly, so a given dew point feels roughly the same regardless of the air temperature around it.
What dew point values feel comfortable versus muggy?+
As a rough guide, dew points below about 10°C (50°F) feel dry and comfortable, 16-18°C (60-65°F) starts to feel humid, and above about 21°C (70°F) feels distinctly oppressive and muggy to most people, regardless of the actual air temperature.
How close can dew point get to air temperature, and what does that mean?+
Dew point can never exceed the current air temperature; when the two are equal or very close, the air is at or near saturation, meaning fog, dew, or frost formation becomes likely, since the air can hold no more moisture at that temperature.
Why does dew point matter for predicting fog or frost?+
Fog forms when the air temperature drops to meet the dew point, since that's the exact condition where excess moisture condenses out. Overnight temperature forecasts are often checked against the dew point specifically to predict whether fog or frost will form by morning.