Atmospheric rivers bring heavy rains and threats of flash floods

They vary in size, depth, and flow velocity, but rivers can also occur in the atmosphere.

When you hear the word river, you think waterway.

They vary in size, depth, and flow velocity, but rivers can also occur in the atmosphere.

They are called – and rightly so – atmospheric rivers.

An atmospheric river works the same as a normal river, but the transported water is water vapor, not liquid water.

These weather conditions can carry billions of gallons of water over thousands of miles.

Most often, atmospheric rivers affect the west coast.

California, Washington State, and Oregon all depend on these huge rain, snow and moisture “fire hoses” for much of their annual precipitation.

However, every now and then an atmospheric river can occur east of the Rockies, even in Texas. When this happens, floods and flash floods become a huge threat.



Atmospheric rivers are formed when a great heightpressure system and a large low pressure system are separated by a narrow band of clouds and humidity.

This moisture is pushed north by the large-scale rotation of the two pressure systems which act like gears to move the moisture.

Within this narrow band, usually a few hundred kilometers wide, regular, moderate to very heavy rains will fall over the same area for an extended period.

When these rivers move over land, they can produce huge amounts of rain and the resulting flooding problems.

In 2016, an atmospheric river helped fuel a storm over Louisiana that dropped more than two feet of rain over Baton Rouge and surrounding areas, causing catastrophic flooding and $ 10 billion to $ 15 billion in damage. In California, 24-hour rainfall amounts greater than 10 inches are common during atmospheric river events.

Fortunately, atmospheric rivers are quite rare east of the Rocky Mountains, but they do occur.

A large-scale weather system characterized by high pressure over Georgia and low pressure over California, as expected this weekend, can result in very heavy rains and flash floods.

About Lucille Thompson

Check Also

The atmosphere of early summer: The DONG-A ILBO

With summer on the horizon, the plums still retain the tartness to their liking, and …

Leave a Reply

Your email address will not be published.