Although winter outlooks typically don’t arrive until mid-October, Accuweather has released a preliminary look at the likely weather for Winter 2006-2007. Not surprisingly, the forecast is pretty typical of what you would expect for an El Nino year.

Meteorologist Joe Bastardi of Accuweather says that the weather along the east coast will likely be stormier than normal — typical of El Nino years. Bastardi predicts a relatively mild start to the season in the Northeast, followed by cooler weather in January and February. Whether this will lead to a greater chance of snowfall is really a matter of timing, since the cold Arctic air must be in place at the same time the storms are.

In the west, Bastardi says the weather is likely to be dryer than normal due to an extended high pressure system, and warmer than normal as well.

None of this is particularly earth-shaking, but again these are September predictions, three to five months out. Look for more specific Winter outlooks to be issued next month by all the major forecasters.

Taking a look at the weather in the short term, though, the cold front passed through the Atlanta area this afternoon, dropping dewpoints by 15 degrees between 2 and 6 PM as the storms cleared out. Behind the front is a taste of fall, with temperatures dropping into the 50s, and highs for the next few days not breaking 80. We may be getting into one of those annoying patterns where bad weather arrives just in time for the weekend for the next few weeks, with long range forecasts calling for a chance of rain this weekend, and again at the end of the month.

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From a meteorological standpoint, winter is over, having ended yesterday. So, how did we do?

Here are the average temperatures, month by month, along with normals:
December: 40.7 46.8 6.1 degrees below normal
January: 48.3 42.7 7.6 degrees above normal
February: 44.3 46.8 2.5 degrees below normal
Winter: 44.4 45.4 1.0 degree below normal

So, we ended up, in the means, about a degree below normal for the winter, although we saw wild swings in the monthly temperatures.

When you take a look back at the early forecasts for winter, it looks like everybody got it right as far as temperatures go, except for the Weather Service, which issued a forecast of equal chances of above or below normal. Kudos go to the Farmer’s Almanac, which predicted the great swings from cold to warm, and then back again.

In the snowfall department, where we really didn’t see anything that caused any major problems at all, Kirk Melhuish got it spot on, with WeatherAmerica and AccuWeather widely missing the mark.

Overall, I would give the best grades to Kirk Melhuish, who was right on both temperature and precipitation.

Speaking of forecasts, I caught Joe Bastardi of Accuweather on Fox News over the weekend, talking about the upcoming hurricane season. While we’re about a month away from the official forecasts, he warned that based on similar patterns in the past, we’re likely to see another active season in 2006, with a probability of hurricanes striking the Atlantic coast, perhaps as far north as the New York area.

Shorter term, we may end up with a more or less normal March. The weather service is calling for equal chances of above or below normal temperatures and precipitation in Georgia for March. Warm weather is expected in Texas, and colder than normal weather is predicted in California. If the Climate Predication Center is right, it will also be rainy in California, and dry in Texas and Florida.

Texas is already feeling the heat, with highs around 90 today. Lawrenceville reached its high so far for the year, with 74.4 degrees. (The normal is 60 degrees). But, it won’t last: after another above normal temperature day tomorrow, it will be cooling down to normal temperatures, although, it’s likely to stay dry for a while, adding to a rainfall deficit for the year.

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The Climate Prediction Center has issued its final Winter Outlook for the December through February period, and the overall forecast is for a warmer than normal winter, with equal chances of above or below normal precipitation everywhere except in the Southeast, where it will be dry, and Hawaii, where it will be wetter than normal.

Long-range winter forecasts can be derived by looking at the El Nino/La Nina sea surface temperatures and recent weather trends. In an El Nino pattern, the jet stream tends to be further south, bringing wetter and cooler conditions to the southeast. In a La Nina pattern, the polar jet stream is further north, bringing warm and dry conditions to the southeast. This winter, we have a neutral pattern, not affected by either phenomenon, so the weather service is looking at recent weather patterns, which have tended to be warmer than the 30 year period from 1970 to 2000.

While the a band from the Southwest to the upper Midwest will see warmer than normal temperatures, there is no real prediction for what we’ll see in the Southeast.

As far as precipitation goes, the Atlanta area is on the edge of an area stretching from middle Georgia into Florida that is expected to see lower than normal rain or snow. This continues a pattern that we’ve seen developing since August, where only tropical activity has brought rain to our area. It’s not being called a drought yet, but there is the chance of one developing.

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With the meteorological start to winter just one month away, forecasters are busy making their predictions for the upcoming season. Here’s a roundup:

National Weather Service: Probably the most non-committal of the lot. They are basically predicting equal chances of above or below normal temperatures and snowfall east of the Mississippi in their second round of forecasting dated October 20th. That’s a bit of a pullback from the initial forecast, which called for a greater than 50% chance of warmer than normal weather into North Georgia. They’ll update their forecast around the middle of November.

Accuweather.com: Between one and two degrees colder than normal for North Georgia, with slightly less than normal snowfall. They are predicting a much colder and snowier winter than normal for New England. In their city-specific forecast, they say it will be 1.5 degrees colder than normal with a mean temperature of 42.8 in Athens, and 43.4 degrees in Atlanta, and 3 inches of snow (normal is 2), both for Atlanta and Athens.

WeatherAmerica: Larry Cosgrove, a meteorologist in New Jersey, issues a regular national short term forecast. His national winter forecast calls for below normal temperatures and above normal snowfall for the southeast, and he warns there could be snow as far south of Interstate 10 in early February. Larry is an excellent writer, and a great read; his forecast goes into a lot of weather details to back up his predictions.

Kirk Melhuish: WSB Radio forecaster is calling for colder than normal temperatures, and less than normal precipitation for the winter. He’ll update his forecast around Thanksgiving.

The Farmer’s Almanac: Their secret weather forecasting system is predicting a wild ride with temperatures going from cold to warm, but in general, they are predicting a colder than normal winter in the South.

The consensus seems to trend towards a colder than normal winter (much to the dismay of those with gas heat), but the jury is still out on snow. With Atlanta lucky to get one or two days of snow a year, it’s tough to know exactly what will happen. Only time will tell.

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The Climate Prediction Center today issued the National Weather Service’s first winter outlook. In summary, the prediction is for warmer than normal weather for much of the country, with equal chances of above normal or below normal snowfall.

For Georgia, the northwest corner of the state is predicted to have a better than 50% chance of above normal temperatures, while the entire state has equal chances of above or below normal precipitation. The image below, courtesy of the weather service, shows the extent of the predicted warmer than normal weather in the nation’s midsection.

The interesting thing to note about the winter outlook is that the weather service doesn’t expect much of an effect from El Nino or La Nina this year. These two phenomena refer to the Pacific Ocean temperatures compared to normal. Because most of our weather patterns flow from west to east, higher or lower than normal Pacific Ocean temperatures affect our weather.

Here on the East coast, and particularly in Atlanta, we are affected by a weather trend called the North Atlantic Oscillation. Essentially, the NAO, as it’s called, measures the position of the jetstream over the Atlantic: if the jet stream is further north, the NAO is positive, while if it’s further south, it’s negative. Unlike El Nino, this pattern changes frequently, and can’t be predicted more than about two weeks in advance.

Because here in the Atlanta area we are usually fairly close to the lowest position of the jet stream, it seems to me that we either have weather that is wet and temperatures too warm to freeze when the jet stream is to our north, or clear dry weather that is cold when the jet stream approaches the area. We rarely get situations that bring snow, when temperatures are cold and a low pressure system moves through.

Overall, the winter forecast closely resembles the December through January forecast issued by the weather service last month. We’ll just have to wait to see what the season actually brings.

Meanwhile, recent weather, providing over a foot of snow in Colorado and the eastern Rockies and torrential rainfall over New England, shows that the inevitable change in the weather pattern from summer to winter is well under way.

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