Wind is almost constant in the Great Plains. The average wind speed in Fargo, day and night, throughout the year, is 12.3 mph. Although the average wind speeds are lower in July and August, summer thunderstorms can produce extremely high wind gusts, usually over relatively small parts of the area.
Air is a fluid and when there is a difference in pressure, air molecules will always move to fill in the areas of lower pressure. So wind is caused not by high or low pressure, but by the difference between higher and lower pressure. The pressure is actually the pressure of molecules moving around in the air, and so is proportional to air density. If more molecules are present, the denser the air is, and the greater the air pressure. The higher the pressure differences are from here to there, the greater the wind.
The main reason the Great Plains is so windy is the lack of trees, hills, and other terrain features to provide friction.
Meteorologist John Wheeler
