When air is moved through grain in a bin, drying will occur only when:

The temperature/relative humidity of the air is capable of absorbing moisture from the grain.

The airflow is great enough to move this moisture through the grain and out of the bin.

To calculate how much drying will occur in grain, we must know how much moisture the air is capable of absorbing. As air becomes warmer and/or drier it will remove more moisture from grain before it is at equilibrium. It is possible to calculate these values and they are referred to as Equilibrium Moisture Content or EMC. Below are some charts showing EMC values for various temperature and relative humidity combinations. NOTE: The EMC values show to what moisture content grains will dry when at equilibrium with the air moving through the bin.