West Coast's 'Bomb Cyclone' Has Arrived

What was expected to be arrived Tuesday evening, knocking out power and downing trees across the region, the reports. The Weather Prediction Center issued excessive rainfall risks beginning Tuesday and lasting through Friday as the strongest atmospheric river—a large plume of moisture—that California and the Pacific Northwest has seen this season bears down on the region. The storm system is considered a " bomb cyclone," which occurs when a cyclone intensifies rapidly.

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