Kentucky has a variable climate, affected by natural phenomena from the south, north, east and west, as well as terrain-sensitive weather conditions like those in valleys, on hill peaks, or in densely forested areas. Though Kentucky is not a coastal state, its climate is affected by factors like wind currents that come from the north that bring winter temperatures down, and a tropical front from the south that creates "warm, humid summers," according to the USDA Forest Service.
The Bluegrass Region of Kentucky is characterized by rolling meadows, streams, springs, and grazing cattle, sheep and horses. The Bluegrass Region is in north-central Kentucky. The Ohio River borders the region's northern and western sections, making it a heavily irrigated and agriculturally well-positioned area. The Bluegrass Region earned this name from its unique, natural abundance of bluegrass. Its northern location makes its climate slightly cooler than the southern regions, yielding an average of 20 inches of snowfall annually.
The Knobs Region has its namesake "knobs," which are steep hills and slopes that extend up to about 500 feet. The Knobs Region surrounds the Bluegrass Region in a horseshoe shape. It is the smallest area of Kentucky, located between the Bluegrass Region, the Pennyroyal Region, Eastern Mountains and Coal Fields, but is identified more often as a part of the Bluegrass Region. Lumbering dominates the Knobs' revenue due to the prevalence of thick forests.
The Pennyroyal Region, one of the largest areas of Kentucky, was named after the pennyrile mint plant, discovered by settlers there. It lies in south-central and western Kentucky, abutting every other region except for the Bluegrass. The landscape of the Pennyroyal is similar to the Bluegrass, with rolling hills and springs. The world's biggest cave structure, Mammoth Cave, is in the Pennyroyal and attracts a lot of tourism. The region has abundant rainfall and the weather patterns characteristic of southern Kansas.
Jackson Purchase Region
Jackson Purchase Region lies on the farthest western point of Kentucky, named after Andrew Jackson who bought the property from Chickasaw Indians in 1818. It is bordered by Kentucky Lake on the east, the Ohio River in the north, and the Mississippi River on the west, creating low flood plains, swamps and small hills. The Jackson Purchase Region is susceptible to flooding due to the flat topography and lack of water drainage. Warm temperatures exceed 40 days a year, due to Kentucky's alignment with the Gulf of Mexico to the south, which brings humid, moisture-saturated winds to the southern and western areas of Kentucky.
Western Coal Field Region
The Western Coal Field Region is above the Pennyroyal and lies in a larger basin that extends from Illinois and Indiana, in northwestern Kentucky. It is rich in coal and oil resources and produces almost half of Kentucky's coal. The Western Coal Field Region is spotted with wetlands due to its closeness to the Ohio River and is supported by its "extensive production of corn and soybeans," according to the Kentucky Climate Center.
Eastern Coal Field Region
The Eastern Coal Fields of Kentucky was the first region of Kentucky to be inhabited by settlers. It is large and rugged, encompassing hills, rivers, streams, and mountain ranges. It lies on the Appalachian Plateau before it reaches west into the Appalachian Mountains. The Eastern Coal Region of Kentucky has a plentiful coal and oil supply, with hardwood and softwood forests populating the landscape.