Estimate the height of the cloud base (LCL) based on surface temperature and dew point.
Atmospheric Stats
Calculation Results
Temperature must be ≥ Dew Point
About this calculator
Overview
The cloud base, or Lifted Condensation Level (LCL), is the height at which an air parcel becomes saturated when lifted from the surface. In dry, well-mixed conditions, it can be estimated using the temperature-dewpoint spread.
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Pro Tips
The 'spread' is the difference between air temperature and dew point.
As air rises, it cools faster (~9.8°C/km) than the dew point drops (~1.8°C/km).
This calculator is a good approximation for convective clouds (like cumulus) on a fair day.
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Fun Facts
"Pilots and glider enthusiasts use this information to find 'thermals' and stay safe during flight."
"If the temperature and dew point are identical at the surface, you get fog instead of high clouds."
"The 125m per degree spread is a standard aviation rule of thumb."
