Humidity is best quantified by the dew point temperature. Higher dew point temperatures express increasing mugginess in the air. For about four hours last Tuesday, the dew point temperature was above 80 degrees and peaked at 83 at the official instrument site at Fargo’s Hector Airport.
Such high humidity is rare in our region, occurring only once in a while every few years or so. It is not easy for our weather to get so humid and you might be surprised by the process. The source region for this high humidity is the Gulf of Mexico. But the dew points along the Gulf in high summer usually hover in the 70s, not the 80s. But as that humid air gets drawn northward, its humidity is increased by Midwestern agriculture. Millions of acres of corn and soybean plants actually add to the humidity by their respiration processes.
And the result, under the right weather conditions, humidity in Fargo Moorhead can go higher than in either Miami or Houston.