A snowstorm of epic proportions is developing along the eastern seaboard of the United States.
It is expected to disrupt the lives of up to 60 million Americans.
At 06:00GMT, the centre of the low-pressure system was lying just off the Virginia coast.
At that time, 10cm had been reported in Lexington, 36cm in Charleston, South Carolina, and 18cm in Nashville, Tennessee.
With predicted accumulations of 60cm to perhaps one metre, this storm is being referred to as the 'storm of the century' or a 'once in a lifetime' event.
But how does this developing storm compare with great storms of the past?
The most recent major snowstorm to hit the northeast was 'Snowmageddon' of February 2010. Eighty-three cm fell at Dulles International Airport, Washington, DC. Thirteen people died in the US during the storm, but far deadlier systems have struck in the past.
Washington, DC was also badly hit during the 'Knickerbocker Storm' of January 1922. Up to 90cm of snow fell across Maryland, Pennsylvania and Virginia. 71cm of snow fell in capital; the snow was heavy enough to cause the collapse of the Knickerbocker Theatre, hence the name.
One of the deadliest winter storms was the 'Great Appalachian Storm', which moved through the eastern US in late November 1950. It brought torrential rain, hurricane force winds (up to 260km/h in the New England highlands) and blizzard conditions. The death toll reached 353.
There will no doubt be questions asked about whether this storm is linked to global warming or the current El Nino.
But the late 1880s saw a series of deadly blizzards, and the world was still only beginning to warm at that time, and we have little knowledge of El Nino before 1950.
In January 1888. 'The Children’s Blizzard' brought a sudden drop in temperatures, and the strong winds produced a wind chill of -40C. Some 235 people died, many of them schoolchildren.
In March of the same year 'The Great Blizzard' struck the northeast. Between 1m and 1.3m of snow fell on Connecticut, Massachusetts, New Jersey and New York. More than 200 ships were sunk by strong winds. The death toll reached over 400.
Yet another 'Great Blizzard' hit the east coast in February of the following year. This one brought the coldest weather ever experienced across some of the southern states. There were blizzard conditions further north with 41cm snow accumulations at Central Park in New York.
The current storm could well match the severity of those mentioned above. Around 60cm of snow could fall in the capital, and up to a metre is expected across the Appalachians, before the storm clears the eastern seaboard just after 12:00GMT on Sunday. However, improved forecasting and better emergency planning mean the death toll will be much lower.
So, is this really likely to be a once-in-a-lifetime event? Not for most of us; it should be pointed out that we are living in a rapidly warming world. The atmosphere can hold much more moisture; sea temperatures are rising. These factors make severe storms more likely.
Of course, life expectancy is increasing in many developed countries, including the US. Many of us stand a greater chance of living long enough to see something of a similar magnitude.
Nevertheless, this storm will live long in the memory of those who suffer its effects in the coming days.
Source: Al Jazeera