Atmosphere
Pressure, temperature, density, and speed of sound in the standard atmosphere.
The ICAO standard atmosphere at any altitude, humidity and dew point relations, and estimates of cloud base and freezing level. Pilots use it to see how far today's air is from standard and to judge where cumulus clouds will form. Start with the standard atmosphere tool for pressure, temperature, and density at a height. The standard atmosphere is a reference model, not a forecast, and the cloud base from the temperature and dew point spread is an estimate for well-mixed air, not a report.
Planning and education aid. Not for primary navigation. Full disclaimer
I want to work out humidity, dew point, and moist air density
- Humidity and moist air
Dew point, relative humidity, and vapor pressure from each other, with the mixing ratio, virtual temperature, and how much lighter the moist air is than dry air.
I want to look up the standard atmosphere at an altitude
- Standard atmosphere
Temperature, pressure, density, speed of sound, and viscosity of the ICAO or US 1976 standard atmosphere at any altitude, on a standard or non-standard day.
I want to estimate the cloud base and freezing level
- Cloud base and freezing level
An estimate of the base of convective clouds from the temperature and dew point, by the 400 ft per degree rule and by the lifting condensation level, and of the freezing level.