The United States is home to a wide range of biomes. Possible habitable biomes include the temperate rain forest, grassland, alpine areas, desert, taiga, tundra and tropical regions.
Most states east of the Mississippi River and the states of Missouri, Arkansas and Louisiana are located in the temperate rain forest biome, which is characterized by cold winters and warm, humid summers. Most of the Midwest is within the grasslands, which has a semi-arid climate with warm to hot summers.
Areas in and around the Rocky Mountains are in the alpine biome. Parts of California, Nevada and Arizona are in the desert biome. Oregon, Washington and southern Alaska are within the taiga biome, which features long, severe winters, and short, humid summers. Northern Alaska is a tundra, with long, dark winters that are especially cold. Hawaii is within the tropical rain forest biome, which is warm throughout the year with brief periods of reduced rain.