Unpredictable Nebraska Weather

Ah, Nebraska—such a wonderful place to sit outside with a cold beverage at dusk while watching the sunset (for only about nine days a year). As is true with other states in the Great Plains, Nebraska’s weather is quite unpredictable and interesting as the state experiences everything from sub-zero to 100+ degree temperatures, floods, droughts and snow storms that leave evidence of their existence for weeks.

The unpredictability of Nebraska weather is caused by many different elements, including wind patterns and physical geography.

Wind Patterns during a June, 2009 Storm
http://extremeinstability.com/wx101.htm

The wind patterns pictured above show black lines representative of surface winds coming from the West and the South and the white lines indicate winds at 18,000 feet. There are two elements that cause Nebraska (or anyplace) to have wind: pressure gradients and the Coriolis Effect. Pressure gradients affect air as it moves from high to low-pressure areas—measured in isobars. As the Great Plains cover a range with steep pressure gradients, the wind is faster (the gradients become steep when the are spread affected strongly in a short amount of space. The Coriolis Effect is essentially taking the Earth’s spin into account when establishing the direction of the wind. As air moves towards higher-pressure areas, Northern air is drawn South towards the Equator.

Example of Coriolis Effect
http://www.waterencyclopedia.com/Ce-Cr/Climate-and-the-Ocean.html#b

The collision of cold, Northern air and moist, warm air from the Gulf of Mexico is not the only reason for Nebraska’s unpredictable weather—the general flatness of Nebraska also plays a roll. Whereas here in Denver, the Rocky Mountains prevent Arctic or Gulf air masses from going West, they also provide a predictable cloud location as warm air moves up the mountains and settles. As Eastern Nebraska sits at 1,000 feet above sea level and the West can rise to over 4,000 feet above sea level, the gradual slope causes no blatant predictable storm locations.

http://www.lincolnweather.org/Forecast-Challenges-in-Nebraska.html

http://outdoornebraska.ne.gov/blogs/2012/11/weather-geek/

http://en.wikipedia.org/wiki/Contour_line#Barometric_pressure