Expect early snow this winter

Hold off on the milk run, but meteorologists are saying the snow shovels could trump the rakes earlier than usual this year.

A cooldown is likely in November, and December may feature snow and cold before the winter takes a milder turn in late January and February, according to the Accu-Weather Inc. winter forecast released this morning.

Meteorologist Paul Pastelok said Philadelphia could expect 24 to 28 inches of snow, well below last season's total.

Still, that would be above the long-term average, about 22.

If that works out, it would mark the first time since the 1960s that Philadelphia officially has had four consecutive seasons of above-average snowfall.

Most of this season's white inventory is likely to come sooner rather than later, Pastelok said.

WSI Corp., a New England-based forecasting service, hasn't yet released its outlook, but it, too, is calling for a chilly November and December. (All suspect science aside, the Farmers' Almanac is calling for a wet and mild winter.)

Meteorologists agree that a prime factor governing the Mid-Atlantic weather will be cooler-than-normal sea-surface temperatures in the equatorial Pacific, a phenomenon known as La Nina. This one is still developing, and while it does not look to become as strong as last year's, they say it will be a player.

Typically, La Nina affects air patterns in such a way that they work against those big East Coast storms that are the region's major snowmakers.

European forecast models are showing storm-repelling high pressure building over the Southeast Coast later in the winter, Pastelok said. Thus he thinks the bulk of the snow will have fallen by mid-January.

"That will spoil our fun for the kids," he said.

However, the forecast comes with mighty caveats. Long-range prediction remains one of the more-tenuous branches of meteorology.

La Nina isn't the only factor. A wild card is the air-pressure pattern in the far North Atlantic, and that isn't predictable beyond about two weeks.

Recall that last October forecasters weren't seeing much in the way of snow for the winter of 2010-11. Accu-Weather called for slightly below-normal snowfall.

Philadelphia ended up with 44 inches, the eighth-snowiest in 125 years of records.