Scientists have issued an ominous warning for the golden state: build your arks now because a biblical "ARkStorm" is heading your way.
Among their predictions, the Daily Mail reports, are walls of 10-foot high water, rain falling in feet instead of inches and millions of homes caught up in floods during a hurricane-like "megastorm" that could last more than a month.
The every-other-century event last happened in 1861 and left the central valley of California impassable. The cost was impossible to quantify - but should a similar event happen today the damage could total more than $300billion.
The U.S. Geological Survey has now begun planning for the return of the ARkStorm, so named after the boat Noah used to escape the flood in the Bible. The capped-up 'A' and 'R' stand for 'atmospheric river'.
They have recruited 17 researchers and a string of agencies to work with local emergency crews and government officials across California to ensure that should it arrive, they would be best prepared for it. The team says that a storm on the scale of that which struck in 1861 is ‘inevitable’ and it was widely considered the worst and longest on record.
USGS chief ARkStorm scientist Lucy Jones said the weather system will start in the Tropics due to atmospheric rivers of moisture forming, grow larger and gain speed as it travels to the West coast of America where it would become roughly the same strength as a hurricane.
It would take some weeks to form, which would hopefully give them time to better prepare when it arrived.
'We think this event happens once every 100 or 200 years or so, which puts it in the same category as our big San Andreas earthquakes,’ she said. ‘Floods are as much a part of our lives in California as earthquakes are. We are probably not going to be able to handle the biggest ones.’