The National Oceanic and Atmospheric Administration (NOAA) has just released its annual winter outlook, reminding us that now is a good time to begin preparations for the cold weather.

According to NOAA’s predictions, another winter of extremes is in store for the United States, due to a strengthening La Nià ±a.

Accuweather.com chief long range forecaster Joe Bastardi also points to the influence of La Nià ±a in his winter outlook.

La Nià ±a winters are typically synonymous with harsh conditions across the northern tier of the U.S. and drier than normal conditions throughout the southern tier, according to Bastardi.

Note: La Nià ±a is associated with cooler than normal water temperatures in the Equatorial Pacific Ocean, unlike El Nià ±o which is associated with warmer than normal water temperatures. Both phenomena, which typically occur every 2-5 years, influence weather patterns throughout the world and often lead to extreme weather events.

Regional highlights of  NOAA’s winter outlook include:

NOAA predicts the Pacific Northwest should brace for a colder and wetter than average winter, while most of the South and Southeast will be warmer and drier than average through February 2011.

However, for the Northeast and Mid-Atlantic the picture is less clear, with equal chances for above-, near-, or below-normal temperatures and precipitation.

Why the uncertainty? Well, NOAA explains that winter weather for these regions is often driven not by La Nià ±a but by weather patterns over the northern Atlantic Ocean and Arctic. These are often more short-term, and generally predictable only a week or so in advance.

If you still have questions, the Weather Channel has the answers in its excellent “Winter’s Top 5 Hottest Questions† segment.

Winter storms can be costly for insurers. Insurance Information Institute (I.I.I.) research shows that winter storms result in about $1 billion in insured losses annually and are the third largest cause of catastrophe losses, behind hurricanes and tornadoes.

According to Munich Re, average annual winter storm losses have increased by more than 50 percent since 1980. A series of winter storms in the Mid-Atlantic and New England states in the early part of 2010 created the highest insured losses for this peril since 2003.