ST. LOUIS • After scattered flurries Thursday, a light blanket of snow is expected this weekend for the St. Louis area.

Some parts of the region saw flurries during the day Thursday with Lambert airport reporting just a trace. Temperatures were expected to dip to around 20 Thursday night and rise to about 33 today, with sunshine.

A fast-moving band of moisture from the Pacific Ocean is expected to collide this weekend with the area’s lingering cold front and produce clouds and more snow.

The National Weather Service predicted a 60 percent chance of snow Saturday afternoon, 70 percent Saturday night and 40 percent on Sunday.

“The majority of the accumulation will take place in the afternoon Saturday and through the evening and will taper off after midnight,” meteorologist Ben Miller of the National Weather Service in Weldon Spring said Thursday.

Accumulation of one to two inches is forecast for the metro area, he said.

On average, the first measurable snowfall in St. Louis occurs on Dec. 4. In recent years, the earliest snow was 0.2 inch on Nov. 3, 1997. The first snowfall of the cold season last year was 0.5 inches on Dec. 5, commencing a cold winter season that brought 31.4 inches of snow.

Average annual snowfall here is 20 inches.

Jayson Gosselin, another meteorologist at the Weather Service office in Weldon Spring, said Thursday the pattern bringing cold air to the Midwest is similar to what made last winter notably cold. But he said it’s too early to say whether the current chill is an oddity or harbinger.

Normal temperatures for mid-November are 57 to 39 degrees. The current cold wave arrived Tuesday, dropping temperatures 40 degrees below Monday’s temps. Thursday’s high beneath wintry gray skies was 32 degrees. The Weather Service expects highs and lows in the 30s and 20s through Wednesday.

Gosselin said the snowfall wouldn’t last long; the Pacific moisture is moving quickly across the United States. The Weather Service forecasts a slightly higher snow total of two to three inches in central and western Missouri, diminishing to one inch across southwestern Illinois.