Why does the inland west region get more rain then the Great Plains?

because it's in a dense forest

Explanation:

inland west region is somehow between the sea and the forest which cause it to rain heavily.

The west inland region receives more rain

Explanation:

The western areas have cascades with fresh abundance and high moistures that flows freely from the ocean. Because these streams are always oriented in some parts of US which usher pacific storms thorough the flooding inducing express throughout the west region. During these periods heavy rains are experienced because of the occurrence of precipitation.

Because of the heavy rains that falls in October, the annual temperatures tend to vary because of high temperatures that are experienced in June and July.