Saturday, October 23, 2010

WINTER WEATHER FORECAST

La Nina forecast to drive winter extremes

By Doyle Rice, USA TODAY
Another winter of wild weather extremes appears to be in store for the USA.
The Pacific Northwest should see a wetter, colder winter than average while most of the Sun Belt stays mild and dry, federal scientists announced in their winter forecast Thursday.

The dominant climate factor expected to affect the USA this winter is La Niña, a periodic cooling of tropical Pacific Ocean water that affects weather patterns across the USA and around the world.

"La Niña is in place and will strengthen and persist through the winter months, giving us a better understanding of what to expect between December and February," said Mike Halpert, deputy director of the Climate Prediction Center.

The center's forecast covers the months of December, January and February, known as meteorological winter.

In the Pacific states and interior Northwest, the cold, wet winter will help replenish water resources and winter recreation, the climate center forecast, but also could lead to greater flooding and avalanche concerns.

The wintry forecast in the Northwest is great news for ski resorts there. "We couldn't be happier with the forecast," said Holly Lippert, communications manager for the Summit at Snoqualmie ski resort in Washington state. The resort picks up 36 feet of snow in an average winter, she said. During the last La Niña winter there, in 2007-08, Snoqualmie received almost 50 feet, Lippert said.

Skimpy precipitation and unusual warmth for most of the southern USA could worsen droughts and spark wildfires from Southern California to Florida. "The story of this winter is likely to be the dry conditions across the South," Halpert said.

Drought already is plaguing the Deep South, according to Thursday's update of the U.S. Drought Monitor, a federal website. In Alabama, 96.7% of the state is enduring severe to extreme drought. The same is true for 91.2% of Mississippi and 82.9% of Louisiana.

Other potential trouble spots are the northern Plains and the Ohio and Tennessee valleys, which could see more storms and flooding.

The outlook does not forecast where and when snowstorms may hit or estimate total seasonal snowfall accumulations. Snow forecasts depend on winter storms, which usually can't be predicted more than a few days in advance, Halpert said.

However, the Mid-Atlantic region isn't likely to see a repeat of last winter's colossal snow totals, Halpert said, because the main winter storm track appears to be closer to the Ohio Valley region. Washington, D.C., which averages 15 inches of snow a winter, got a record 56 inches in the winter of 2009-10.

A dry, mild winter would be welcome news in Maryland, where the state Department of Transportation spent $120 million last winter on snow removal, blowing its budgeted amount of $26 million, department spokeswoman Valerie Burnette Edgar said. "We're prepared, but if we get another winter like the last one, it'll be a challenge."

Contributing: The Associated Press

No comments: