Pineapple Express: Atmospheric rivers bring high wind gusts and power outages throughout US

The US West Coast welcomes an ‘atmospheric river’ that is expanding through the region. Heavy rains and power outages have been reported amidst the chaos caused by these weather patterns.

The atmospheric river that is affecting the U.S. West Coast is also known as the “Pineapple Express”. It occurs when atmospheric winds transport water vapour from the Pacific Ocean. The vapour gets picked up from Hawaii and travels like a jet stream into the Western region. It then hits the mountain ranges from where it develops into a heavy rainfall or snowfall upon contact. Many mountain ranges in the West owe a large percentage of their annual precipitation to the atmospheric river.

Atmospheric rivers, as the name suggests, are like rivers in the sky. The reason it is called a river is due to the vast amount of water that is transported by these winds. The average water vapour transferred by this weather pattern approximately amounts to the average flow of water at the mouth of the Mississippi River. Their tremendous capacity is known to be the cause of many heavy rainfalls, floods and catastrophic damages to life and property. Atmospheric rivers usually vary in their intensity.




California will bear the impact of the atmospheric rivers on Tuesday. Rain is expected throughout the day along the California coast. Cities like Los Angeles, San Francisco, San Diego are also going to be affected. Snow is expected at Sierra Nevada. The National Weather Service has also warned citizens to be aware of localised flash floods in central California.

More than 10,000 people have endured power outages in Washington already while another 70,000 have witnessed the same in Oregon. Oregon has also seen wind gusts of 82 mph in Rockhouse. The storm is likely to last throughout the week and is expected to reach Colorado by January 4.

FAQs:

1. What is an atmospheric river?
   Atmospheric rivers are a weather pattern that occur when atmospheric winds carry large amounts of water vapour.
2. Which states have been affected by the “Pineapple Express” till now?
   Washington, Oregon and California are the states that have been affected until now by the “Pineapple Express”.