THIS one came two nights after Christmas but it brought a mighty city to its knees.

The blizzard of 2010 will go down in history as the sixth deadliest of its kind since the 1800s when records began to be kept.

New Yorkers stayed home, and stayed put, all day Monday because there was no way to move around, not by foot, car, bus or train, which all came to a complete stop due to 20 inches dumped in the metro area with wind gusts of up to 70 mph.

On Wednesday, as we are putting this issue to bed, the city is still digging itself out of the mountain of snow in unplowed streets and intersections.

Normally unflappable residents turn their ire on the mayor for the slow cleanup.

The mayor responded in kind to the intense criticism.

Asked if he regretted not declaring a snow emergency, 
Mayor Bloomberg icily replied, “I regret everything in the world.”

A mayoral ally, City Council Speaker Christine C. Quinn, conceded the city’s response was the worst in history.

“Clearly, the response was unacceptable,” she said.

The council would hold a hearing to find out which city agency screwed up.

In Queens, as in the other outer boroughs, many major roads remained impassable until late Tuesday.

It will take days before mass transit will be operating a full schedule.

The three area airports are only beginning to resume flights to bring stranded passengers to their destinations.

Thankfully, the blizzard struck after a holiday and classes are on a week’s vacation.

Still, it wreaked havoc on post-holiday shopping and commercial and business establishments lost revenues.

What is confounding is that in a decade of global warming, recent winters have been so cold.

A forecaster blames Siberia for this phenomenon.

How so?

Cold air from Siberia, wrote Judah Cohen, the director of an environmental research firm, spills south into East Asia and then into Europe.

This brings extraordinarily snowy and cold winters in Eastern United States, Northern Europe and East Asia.

“The reality is, we’re freezing not inspite of climate change but because of it,” argued the forecaster.

In other words, there will be more snow job looming for New York City’s weather responders.

So they should be prepared to retool their resources to cope with the elements.

It won’t be enough for a mayor to say, “I feel your pain.”

More than empathy, the city needs instant and adequate response in the event of another emergency.