Extreme is definitely the best way to describe the rain and snow expected toinundate California and Arizona this week. One or more yardsticks will beneeded to measure the snow set to bury the mountains of these two states. Skienthusiasts will definitely welcome the snow but will have extreme difficultyreaching the resorts. In fact, travel will become nearly impossible in thepasses.Looking at the rainfall map, you can see that a yardstick could also be used tomeasure this week's rain across California. The heaviest rain will inundate thewest- and south-facing mountain slopes, especially across SouthernCalifornia.

Notice the deserts will not be exempt from substantial rainfall. Some placeswill receive at least half of their typically annual rainfall just this week.

It is then easy to understand why flooding is such a serious concern.

Story by AccuWeather.com Senior Meteorologist Kristina Pydynowski