As outdoor temperatures warm during late winter, spring, and early summer, the potential for grain storage problems increases, along with the need for grain monitoring and management.
Temperature fluctuations are common in spring
During a typical day, the outdoor air temperature may fluctuate by 25 to 30 degrees. This warms the bin and the grain next to the wall during the day, but during the night, the bin and the grain next to the wall are cooled. The result is that the bin and grain near the bin wall will be near the average temperature.
The same will occur during an extended warm period, followed by a cool or cold period. The grain temperature will be near the average of the two periods.
Grain is an insulator, so grain temperature fluctuations are limited to the grain adjacent to the bin wall. Dry grain that has been cooled to 20 to 30 degrees in northern regions and 30 to 40 degrees in central states is not expected to be affected by these temperature fluctuations.
The stored grain temperature increases in parts of a bin in the spring due to solar heat gain on the bin.
Solar energy produces more than twice as much heat gain on the south wall of a bin in the spring as it does during the summer. This, in addition to the solar heat gain on a bin roof, can create an environment conducive to grain spoilage. A ten-degree increase in temperature reduces the allowable storage time of grain by about one-half. For example, the storage time of corn at 17% moisture is reduced from about 130 days at 50 degrees Fahrenheit to about 75 days at 60 degrees and only 45 days at 70 degrees.
Source : umn.edu