metpy.calc.k_index(pressure, temperature, dewpoint)#

Calculate K Index from the pressure temperature and dewpoint.

K Index formula derived from [George1960]: K = (T850 - T500) + Td850 - (T700 - Td700)


T850 is the temperature at 850 hPa T700 is the temperature at 700 hPa T500 is the temperature at 500 hPa Td850 is the dewpoint at 850 hPa Td700 is the dewpoint at 700 hPa

Calculation of the K Index is defined as the temperature difference between the static instability between 850 hPa and 500 hPa, add with the moisture at 850hPa, then subtract from the dryness of the airmass at 700 hPa.

  • pressure (pint.Quantity) – Pressure level(s), in order from highest to lowest pressure

  • temperature (pint.Quantity) – Temperature corresponding to pressure

  • dewpoint (pint.Quantity) – Dewpoint temperature corresponding to pressure


pint.Quantity – K Index