“We’ve been a little surprised this year ,” said Meteorologist Steve Keighton of the agency’s Blacksburg, Va., office, which monitors climactic conditions for nine Northwest North Carolina counties including Surry.
Although a milder season was expected for 2010-2011, it has been anything but, Keighton added of the unexpected harsh treatment by Old Man Winter.
That has included three snowfalls during December and the one this week that have already dumped nearly 9 inches on the Mount Airy area, based on figures compiled at F.G. Doggett Water Plant. That included 6.80 inches last month and another 2.1 inches this week.
Temperatures also have been noticeably colder than normal. In December, the mercury averaged 32.1 degrees here — nearly 7 degrees lower than the usual mark of 38.8 degrees.
That points to one element of surprise — the presence of “so many of these cold blasts that have come down from Canada and kept things cold,” Keighton said.
Such conditions might not seem unusual as winters go. But they are, considering the fact that this year the region was supposed to be under the effects of a “La Niña” weather pattern, whereby lower-than-normal sea surface temperatures in the Pacific Ocean influence conditions nationwide.
A typical La Niña winter means drier and milder weather across the South — something yet to surface so far. “But the winter’s far from over,” the National Weather Service meteorologist said.
“Last year, we had a real significant El Niño situation going on,” Keighton said of the counterpart to La Niña which often precedes it in a strong way and brings the opposite effects. That wetter pattern coincided with several major snowstorms during the winter of 2009-2010, along with colder weather.
“So that seemed to make sense,” Keighton said of last year’s conditions that matched expectations. This followed several years of mild winters.
La Niña usually means less storms tracking up the coast toward Northwest North Carolina and more influence from the Ohio Valley, which tends to correspond with freezing rain and similar activity, Keighton said.
This winter has ended up bringing some coastal storms from the south to this area, although the meteorologist pointed out that the resulting snow accumulations haven’t been that significant.
“There are no strong signals as far as what we can expect the rest of the winter,” Keighton said. However, weather models from the Climate Prediction Center of the National Weather Service show milder or near-normal conditions for both the short and long term.
A warmer trend is expected in the next couple of weeks, Keighton said, but the question is how long it stays around. The long-range outlook is for milder temperatures than what have been experienced thus far, with the situation to be “pretty close to normal” through March, he said.
“Near-normal” precipitation also is expected for that same period, Keighton added, but he left room for the possibility of more surprises.
“That’s always a tough thing, to be able to correlate overall season trends.”
Yearly Totals Down
December’s storm activity did not keep Mount Airy from finishing 2010 at a slight precipitation deficit, according to other water plant statistics.
For the month, 4.09 inches were measured, the net amount from the snow received as well as rain, which exceeded the 3.46 inches that is normal for December. In all, measurable precipitation occurred on seven days last month, with the most for a one-day period logged on Dec. 1, 2.76 inches.
But Mount Airy’s total output for 2010 was 45.38 inches, .12 inches — or .26 percent — below normal.
Last month’s temperature extremes ranged from 64 degrees on Dec. 1 to 12 degrees on both Dec. 10-11.
Contact Tom Joyce at email@example.com or at 719-1924.