Philly has a chance for its biggest snow of the season to date. It won’t take much.

Snow was coating roads in parts of southern Chester County Friday, and on the coldest morning of the season to date, flakes have crept as far north as Philly.

The odds are against it, and it may require a depth micrometer to determine the outcome, but Philly has an outside shot of experiencing its first “measurable” snow of the season.

Yes, PennDOT is aware of the potential flake invasion, and crews and trucks are on stand by, said spokesperson Krys Johnson.

On Monday and on Nov. 18, “traces” — defined as at least one flake sighted officially — were reported at Philadelphia International Airport, but an accumulation of at least 0.1 inches is a requirement for an actual snowfall.

The smart money says Philly won’t get that elusive tenth. It’s not out of the question, said Eric Hoeflich, meteorologist at the National Weather Service in Mount Holly, where it was not snowing. But, he added, “It’s going to be tough to eke out any accumulation.”

“Philadelphia is right on the edge” of the snow line’s northern boundary, he said.

Snow in early December does happen around here, but lack of it is the norm. The “normal” value for snowfall through a Dec. 5 is 0.4 inches at PHL.

Philly’s snow season typically peaks in late January into February as the prime moisture source — the Atlantic Ocean — has a chance to chill, and the cold air in the upper atmosphere ripens.

It’s certainly cold enough for snow. Lows overnight fell into the 20s, officially 25 degrees at PHL. Mount Pocono set a Dec. 5 record with a reading of 4 below zero. That’s Fahrenheit.

Temperatures may not get above freezing Friday, and no higher than the low 40s Saturday and Sunday, which would be several degrees below the long-term daily averages. Another cold front is due Sunday, and readings likely won’t get out of the 30s on Monday and Tuesday.

No further flake sightings are expected.