Los Angeles braces for SIX MONTHS worth of rain in just THREE DAYS as second Pineapple Express winter storm looms

Los Angeles braces for SIX MONTHS worth of rain in just THREE DAYS as second Pineapple Express winter storm looms:

By BETHAN SEXTON

California is set to be lashed by up to six months worth of rainfall in just three days as the strongest atmospheric river storm of the season sweeps in.

Residents are being being warned they may be evacuated as up to a foot of water deluges the golden state.

About 13.5 million are people due to be under alerts for 'excessive rainfall' on Monday.

Coastal areas are expected to be worst hit, but there is the potential for 'life-threatening floods' in all areas including highly populated urban areas such as Los Angeles, according to the National Weather Service.

'Streams and small rivers, as well as the Los Angeles River through the San Fernando Valley and metro LA will rise quickly and turn into very dangerous raging rivers,' the body warned. 'Many roads will be impassable due to flooding.'

It comes on the heels of a soaking Pineapple Express weather system which hit last week which drench the state and led to rescues (pictured)

The storm is the result of the second Pineapple Express weather system to hit in the past week.

The alert has been issued for Sunday night into Monday, with residents urged to start preparing for possible evacuations during or 'even before the storm hits'.

However an area of low pressure will draw moisture in from late Saturday, before aiming the storm at California for several days.

'The last atmospheric river event that we went through, there was movement,' FOX Weather Meteorologist Britta Merwin said. 'This time there's going to be less movement, which means extreme rain totals.'

Everywhere in the state will experience some rainfall, but precipitation is forecast to be worst along a 300-mile stretch of coast as the storm spreads from San Luis Obispo and Santa Barbara south through Los Angeles and San Diego counties.

Communities on the south-facing slopes of mountains and foothills are expected to receive the heaviest downpours, leaving them most vulnerable to potential flash floods, mud flows and landslides. 

Hillsides and canyons scarred by recent wildfires are particularly prone to washouts.

Meanwhile, the Los Angeles metro area could see five inches of rain or more on Sunday, with total up to 12 inches in the mountains. Typically, Los Angeles receives around 14 inches of rain in a year. 

'This is the type of rain that they cannot handle,' Merwin added. 'This is a guaranteed flood setup. There's no way around it. We know it's going to be bad, and there's going to be huge impacts.'

Forecasters are particularly concerned as the storm is due to land on already saturated ground following last week's downpours.