Frost point is when the air no longer has the energy to hold water in vapour form. Frost point works in a similar way to dew point except the conditions are such that the water cannon remain as a liquid. As a result, we will use a slightly different formula for calculating frost point based on air temperature and dew point temperature.
Frost Point = d - a + 2671.02 / ((2954.61 / a) + 2.193665 * math.log(a) - 13.3448)
a = Air temperature in Kelvin d = Dew point in kelvin