The humidity detector provides exceptionally accurate grain moisture measurement in real time. The humidity detector uses low-power microwaves to penetrate the surface every 0.2 second and obtain interior moisture readings without causing any damage. An integrated temperature probe ensures the readings are accurate from 5°C to 55°C / 41°F to 131°F. Suitable for the continuous monitoring of moisture in corn, soybeans, wheat, rice, sorghum, barley, oats, rye, hops, green coffee, cocoa beans, oil seeds, flax seeds, sunflower seeds, poppy seeds, pumpkin seeds, spelt seeds, buckwheat, sesame, peas, fava beans, scarlet runner beans, triticale, amaranth and jatropha.