Biggest snow of the week is possible for parts of Philly and South Jersey early Saturday

Parts of Philadelphia and South Jersey that were snubbed by Tuesday’s snow may get a modest payback during the weekend as winter continues its modest comeback.

Forecasters were confident Thursday that a storm will spin out some snow across the region during the early morning hours of Saturday, with 2 to 3 inches possible and Philly, South Jersey, and northern Delaware favored for the higher amounts.

As opposed to a well-juiced coastal storm, this one will be a so-called Alberta clipper, said Joe DeSilva, a meteorologist at the National Weather Service Office in Mount Holly, so named because they originate in western Canada and speed across the United States. Another variant is the “Saskatchewan screamer.”

Usually those things pass by to the north and shed a few flakes over Philly, if that, but this one will track south of the Philly region.

“Near and south of Philly probably will see more snow than they saw” on Tuesday, said Alex Staarmann, another weather service meteorologist. “It will be falling at night, and it’s going to be a little bit colder.”

» READ MORE: For parts of Philly on Tuesday, it was the case of the missing snow

In terms of impacts, the timing couldn’t be better. Most of it will be falling while the majority of the citizenry, presumably, will be in bed. It is due to start around 1 a.m. Saturday and be over by mid-morning..

That would be quite a contrast to Tuesday, when the snow was at its most intense during the peak morning commuting period.

Another thing is all but certain: If it does snow, what lands won’t be nearly as waterlogged as what descended upon the city Tuesday.

While up to 10 inches fell upon outer Bucks, Chester, and Montgomery Counties, officially 0.6 inches of snow was measured Tuesday at Philadelphia International Airport.

» READ MORE: Why is Philly's snow measured at Philadelphia International Airport

Places to the north and west were getting snow rates up to 2 inches an hour. PHL was getting it at the rate of an inch every seven hours.

The rain changed to snow around 7 a.m. at the airport, and the estimated precipitation total after the changeover was 0.2 inches.

Based on the standard snow-to-liquid ratios, on average that would have resulted in 2 to 3 inches of actual accumulated snow — similar to what is forecast for Saturday, when a similar amount of precipitation is forecast to fall.

The path of the storm favored higher precipitation amounts to the north and west, but small differences in temperatures were a huge factor in the snow totals. Being on the urban heat island and closer to sea level than the hills to the north and west, the airport was a critical degree or two warmer than in the snowbelt. In Pottstown, it was 32 during the snowfall, and at PHL, it toggled between 33 and 34.

» READ MORE: Recent snow could mean a big weekend for Poconos skiing — finally

Temperatures decrease with height, and as nearby as Roxborough, a neighborhood where elevations of 350 feet and more are common, 4-plus inches accumulated. Totals in the flatter lands of South Jersey generally were 1 to 1.5 inches.

Not much at all was sticking in Center City, South Philly, or the airport.

“The snow was melting as it was falling,” said Staarmann.

This time the precipitation amount may be similar to what it was while the snow was falling Tuesday, but it would produce more snow.

A storm is due to track from the Tennessee Valley to the Virginia-North Carolina border and then off the coast. Being on the north side of the track, colder air will be in place than was the case on Tuesday, when the snow arrived after five consecutive days of 50-degree readings. The amount of snow that precipitation produces depends in part on temperature; the colder it is, the more snow.

Wednesday’s high of 40 degrees made it the coldest day of the month, believe it or not. Similar temperatures are expected the rest of the week.

The snow early Saturday would occur with temperatures below freezing even at PHL.

Ah, no.

The weather service says it is confident that some snow is going to happen, but amounts are always elusive.

» READ MORE: Why Philly storm forecasts have been conflicting and constantly changing this winter

Will computer runs the next two days be all over the place about the outcome?

Will a snowball melt on a hot grill?