The USGS Upper Midwest Environmental Sciences Center considers it to be the six states of Illinois, Indiana, Iowa, Michigan, Minnesota, and Wisconsin, which comprise the watersheds of the Upper Mississippi River and upper Great Lakes.
The USGS Mineral Resources Program considers the area to contain Illinois, Indiana, Michigan, Minnesota, and Wisconsin.
The Association for Institutional Research in the Upper Midwest includes the states of Iowa, Minnesota, North Dakota, South Dakota, Wisconsin, and the upper peninsula of Michigan in the region. According to the Library of Congress, the Upper Midwest includes the states of Minnesota, Wisconsin, and Michigan.
Agriculture
The USDA reported that corn, soybean, sunflower, and sugar beet crops saw harvest gains in 2018, but were still below the five-year averages. In North Dakota, for example, 49% of corn was harvested by November 4 compared with the five-year average of 97%. This was in part due to weather conditions in October that affected the harvest.
Climate
The region has dramatic variations between summer and winter temperatures; summers are very hot; and winters are very cold. For example, Sioux Falls averages 25 days each year with temperatures above and 45 days each year with temperatures below. Mitchell, South Dakota has a record high of and a record low of. The growing season is shorter, cooler, and drier than areas farther south and east. The region's western boundary is sometimes considered to be determined by where the climate becomes too dry to support growing non-irrigated crops other than small grains or hay grass.
The Upper Midwest was the heartland of early 20th-century Progressive Party politics, and the region continues to be favorable to the Democratic Party and moderate Republicans, with Minnesota favoring each Democratic presidential candidate since 1976 and Wisconsin from 1988 to 2012. Minnesota narrowly supported native Walter Mondale in 1984 in an election where Ronald Reagan won every other state. Michigan, Illinois, and Wisconsin also often favor Democratic candidates. However, beginning with the 2010 midterm elections, Republicans experienced substantial gains in state legislative and executive offices in Iowa, Minnesota, Wisconsin, and Michigan. This trend has continued through 2016. Currently there are three Democratic governors in the region and three Republican governors. Donald Trump's 2016 presidential campaign made significant in-roads in the Upper Midwest. Trump won the electoral votes of Iowa, Wisconsin, Michigan, North Dakota, and South Dakota, leaving Illinois and Minnesota the sole Blue States in the Upper Midwest in 2016. Hillary Clinton barely won Minnesota, finishing less than 2 percentage points ahead of Donald Trump.
Industry and tourism
The economy of the region was largely based upon the mining of iron and copper, as well as a very large timber industry. Mechanization has sharply reduced employment in those areas, and the economy is increasingly based on tourism. Popular interest in the environment and environmentalism, added to traditional interests in hunting and fishing, has attracted a large urban audience who live within driving range.