Winter: February prospects

Barring a prolonged polar outbreak that the computer models aren't seeing, the winter of 2012-13 will go into the Philadelphia record books as the second consecutive winter of above-normal temperatures.

By Friday, the first two months will have averaged about 4 degrees above normal, although the recent cold snap -- and this one was quite impressive -- has all but knocked this winter out of the elite category for mildness.

For five consecutive days, ending Saturday, the official temperature at Philadelphia International Airport failed to reach 30, the first such stretch since the one that ended on Jan. 28, 2004, exactly nine years ago.

The Coast Guard is reporting some waterway icing, said Gary Szatkowski, meteorologist in charge of the National Weather Service, something unseen last winter.

After a wild Wednesday, when temperatures could rock past 60, accompanied by thunder and lightning, the cold returns in time for February, although not with last week's severity.

By the second week of February, another warmup is in the forecast, but no premature spring shows up in the long-range outlooks.

As for snow, what we saw this morning was in keeping with the character of the season. Several observers weighed in with under a half-inch or less, and we anticipate a similar report from the airport.

That would nudge the seasonal total to just about 4 inches, making it officially snowier than all of last winter, but barely matching the minimum need for a single winter-storm warning.

The biggest snow of the season for Philly was the magical moonlit 1.5 inches that landed on Friday, somehow squeezed out of almost no moisture.

Typically, around here an inch of snow accumulated for every 0.11 inches of precipitation, an 11:1 ratio. 

On Friday, only 0.07 inches of liquid was measured at the airport, converting to a ratio of 21.5:1.

Gary Szatkowki, the meteorologist in the charge of the National Weather Service in Mount Holly said he couldn't recall seeing ratios that high in this area.

In short, the heftiest snow of the season required a magic act.

In terms of snow, it seems that everything has been a struggle this season. Elevated areas north and west of city have fared better with the modest storms that have affected the region, but "nuisance snows" might be overstating the case.

"I wouldn't call them nickel-and-dime systems," said Szatkowski, "more like penny and 2-penny systems."

All that said, winter has a long way to go, and February, climatologically, is the region's snowiest month.

An absence of bitter cold is no impediment to snow. For example, the 15.1-inch storm of January 2011 came after a cold spell had eased.

One big snow would be enough to push the seasonal total toward normal, said Szatkowski.

Without blocking in the North Atlantic or an energized southern storm track, so far conditions haven't been right for the Big One, and some years, as we've noted, the Big One never comes.

Nevertheless, it would be unwise to give up on winter on Jan. 28. Climatologically, about half of Philadelphia's snow occurs after Feb. 1.

Said Szatkowski, "There's still plenty of winter ahead."