Annually, precipitation has increased about 0.31 inches per decade across the Midwest. Most of the precipitation increases occurred during the warm season. Annual snowfall amounts have decreased across the western and southern portion, while snowfall increased along the northern portion. Climate models simulate an increase in average annual precipitation along the northern tier and a decrease in the southwestern portion. Generally, the upward trend will continue during the winter, spring, and fall across much of the region, while the southern portion is expected to decrease during the summer.
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