Sydney - 7.87 Inches Of Rain In 24 Hours - About Six Weeks' Worth In Total

[hatrack]

Sydney has switched from its driest start to the year since 1965 to one of its wettest weeks in March after up to 200 millimetres of rain fell in 24 hours this weekend - 1½ times the monthly average, a meteorologist says.

The rain is expected to continue until Wednesday morning before skies clear and temperatures rise again, Brett Dutschke at weatherzone.com.au said.

But the weakening of La Nina and the cooling of waters offshore also mean that the heavy rains are not expected to stretch into the rest of autumn and winter, Mr Dutschke said.

EDIT

Mr Dutschke said that, on Saturday and yesterday, 99 millimetres fell on the city - the highest 24-hour total in 3½ years, with the heaviest downpours of about 150 to 200 millimetres along the beaches and the northern suburbs. "It's been a big turnaround in events, given that Sydney has been one of the parts of the state that has really missed out on La Nina-type rainfall," he said.

EDIT

http://www.smh.com.au/environment/weather/sydneys-heavy-weather-six-weeks-rain-in-a-day-20110321-1c2t7.html?from=smh_sb

[Systematic Chaos]

1. Thanks for braving the stoopid and trying to get a word in edgewise.

:D

[GliderGuider]

2. Rivers in the sky

Rivers in the Sky

Like freight trains loaded with water vapor, atmospheric rivers are long, narrow bands whose winds funnel huge amounts of moisture through the sky. When they hit coasts, these rivers can drop their moisture as rain and cause destructive flooding, as in January 2005 when more than 20 inches of rain soaked southern California, killing 14 people and causing hundreds of millions of dollars in damage.

Completely unknown just over a decade ago, these rivers turn out to be not only a key factor in Western flooding and water supply, but also a major player in the planet’s water cycle.

At any given time, somewhere between three and five atmospheric rivers are typically ferrying water in each hemisphere. More than 1,000 kilometers long, they are often no wider than 400 kilometers and carry the equivalent, in water vapor, of the flow at the Mississippi River’s mouth. “That has really captured the imagination of scientists,” says Marty Ralph, also a meteorologist at the Boulder lab. “There are only a handful of these events, and yet they do the work of transporting 90-plus percent of water vapor on the planet.”

Ordinary clouds don’t carry lots of water vapor long distances; they rain out as soon as water droplets coalesce and get heavy enough to fall as precipitation. In the 1990s, MIT researchers calculated from wind and moisture data that jets in the atmosphere, which the scientists termed atmospheric rivers, must exist to help ferry water around the planet.

Perhaps climate change is shifting the flow patterns of these rivers? It's an intriguing possibility to explain the rainfall variability we're starting to see.