There's a point at which conventional rock salt cannot win the battle against miserable winter weather. It's at about 15 degrees Fahrenheit.

So with temperatures forecast to plummet as a sluggish storm deposits up to a foot of snow on the region by Friday, Schenectady General Services Commissioner Carl Olsen was well into a backup plan late on New Year's Day.

Public works crews had mixed several hundred tons of stone chips with the salt to help cars gain traction on what will likely be icy, snow-packed roads.

"Salt will not work," Olsen said. "People should obviously be very careful driving."

Meanwhile, Gov. Andrew Cuomo warned that the impact of two storms hitting New York simultaneously — one upstate, one downstate — could test the state's ability to respond and could trigger major road closures on Long Island and in the lower Hudson Valley.

"If we have to work statewide, that obviously is going to stretch our equipment and resources and personnel," Cuomo said. "This is a serious situation. ... We've learned the hard way in New York that Mother Nature is nothing to be trifled with."

The National Weather Service says the Capital Region will be hit by both weather systems — one coming from the west off the Great Lakes that will trigger snow early in the storm and another off the coast that will hit on Thursday and stay into Friday.

While there will be some breaks, the storm will linger for more than 30 hours, not tapering off until early Friday, the weather service said.

The Albany area is forecast to get between 6 and 12 inches, with the heaviest snow falling around the evening rush hour Thursday into Thursday night, said Luigi Meccariello, a weather service meteorologist.

The storm will taper off Friday morning, giving way to dangerously cold temperatures in the single digits to below zero across the region, Meccariello said.

Cuomo said those frigid temperatures — along with the possibility of high winds — could complicate the state's response.

Officials were preparing for the worst upstate along the I-84 corridor and the I-87 leg of the Thruway between Albany and New York City.

The storm is shaping up to be the second major event of the season for the area. On Dec. 14 and 15, 11.5 inches fell in Albany and more than a foot in many surrounding areas.

Albany is already several inches ahead of its average snowfall. As of Wednesday morning, 22.1 inches had fallen this season, nearly half a foot more than the 16.5-inch average.

While the gradual pace of the storm will help workers stay ahead of the drifts, Olsen said it also threatens to exhaust snow-removal crews. "It stretches your workforce a little," Olsen said. "We're going to have to keep crews working for probably 48 hours or more."

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