<P> Once it moves over the Great Plains, uninterrupted flat land allows it to reorganize and can lead to major clashes of air masses . In addition, moisture from the Gulf of Mexico is often drawn northward . When combined with a powerful jet stream, this can lead to violent thunderstorms, especially during spring and summer . Sometimes during winter these storms can combine with another low pressure system as they move up the East Coast and into the Atlantic Ocean, where they intensify rapidly . These storms are known as Nor'easters and often bring widespread, heavy snowfall to New England . The uninterrupted flat grasslands of the Great Plains also lead to some of the most extreme climate swings in the world . Temperatures can rise or drop rapidly and winds can be extreme, and the flow of heat waves or Arctic air masses often advance uninterrupted through the plains . </P> <P> The Great Basin and Columbia Plateau (the Intermontane Plateaus) are arid or semiarid regions that lie in the rain shadow of the Cascades and Sierra Nevada . Precipitation averages less than 15 inches (38 cm). The Southwest is a hot desert, with temperatures exceeding 100 ° F (37.8 ° C) for several weeks at a time in summer . The Southwest and the Great Basin are also affected by the monsoon from the Gulf of California from July to September, which brings localized but often severe thunderstorms to the region . </P> <P> Much of California consists of a Mediterranean climate, with sometimes excessive rainfall from October--April and nearly no rain the rest of the year . In the Pacific Northwest rain falls year - round, but is much heavier during winter and spring . The mountains of the west receive abundant precipitation and very heavy snowfall . The Cascades are one of the snowiest places in the world, with some places averaging over 600 inches (1,524 cm) of snow annually, but the lower elevations closer to the coast receive very little snow . </P> <P> Florida has a subtropical climate in the northern and central part of the state and a tropical climate in the far southern part of the state . Summers are wet and winters are dry in Florida . Annually much of central and southern Florida are frost - free . The mild winters of Florida allow a massive citrus industry to thrive in the central part of the state, and Florida is second to only Brazil in citrus production in the world . </P>

What us state is divided into 2 land masses