The Weather Service has issued its report on Winter, 2006, with the highlight being the above normal temperatures in January, particularly in the plains states. The temperature rankings for the past winter are shown below.

Georgia ranked about in the middle for both temperature and precipitation, with 67th warmest average out of 111 years reported, and the 50th wettest year for the 111 year period.

Meanwhile, the Peachtree City office of the weather service has issued its annual Shareholders Report, with weather highlights in North and Central Georgia for 2005. Highlights include the record number of tornadoes reported during the year, and the effects of the 2005 hurricanes, particularly Katrina. You’ll need Adobe PDF reader to view the report.

Four days away from the astronomical start of Spring, Atlanta is preparing to host two of its highest profile outdoor events over the next two weeks. Sunday, NASCAR comes to Atlanta Motor Speedway for the Golden Corral 500. Unfortunately it looks like we may be due for a spring storm, with rain 60% likely for most of the day, and highs only in the low 50s.

The race was pushed to a later date several years ago because of persistent bad weather problems, including a major snowstorm in March of 1993 that shut down much of the country.

The other big event is the BellSouth Classic golf tournament, held here in Gwinnett on March 30th through April 2nd. Although we’re two weeks away from that, the GFS model now shows rain on Thursday, moving out on Friday. Last year saw sleet and rain, and a shortened tournament as a result. We’ll see what this year brings.

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.

Today’s high temperature of 39 degrees is the coldest high daytime temperature we’ve seen since … last Sunday. However, prior to that, you would have to go back to January 17th, 2005 to see a day when the high temperature was lower. The two cold days mark bookends to a week that also saw the year’s highest temperature to date on Thursday, with a high of 72.8 degrees.

Today’s cold was amplified by the wedge effect, which trapped the morning’s cold temperatures under warmer air aloft. However, we were spared the worst of the weekend’s cold. When I got up this morning, it was 32 in Atlanta, and 21 in Chattanooga. However, 40 miles to the northwest, in Altamont Tennessee, the temperature was a frigid 9 degrees.

After another cold day on President’s day, expect things to warm up, although stay rainy through Thursday. Friday looks to be the nicest day of the week, and then a pattern change brings cold, dry weather in, quite possibly through the end of the month. Both the 6-10 day and 8-14 day forecasts call for colder and dryer than normal temperatures through the period which ends on March 5th. This is especially true for the end of the period, when highs could struggle to make 50 degrees, and overnight lows will be in the mid 20s.

The long-range forecast for March as a whole calls for a slight chance of above normal temperatures, and normal rainfall. It seems like groundhog Beauregard Lee needs to get busy if he wants to salvage his prediction of an early spring.

As predicted, the mass of cold, Arctic air is beginning to make its way south. This evening, a surface low is centered over the center of Missouri: as of 8 PM Eastern time, it was 68 degrees in St. Louis, while on the other side of the state, in Kansas City, the temperature has dropped to 32 degrees. It’s already below zero in places like Bemidji, Minnesota, where tomorrow’s high is expected to be a frosty 14 below.

The cold air is going to continue to come towards the Atlanta area. Meanwhile, a high pressure system in the Caribbean is working to block its advance. At the same time, upper air from the southwest continues to bring moist air into the region, along with the possibility of precipitation.

The whole scenario brings a lot of uncertainty to the forecast. One possibility is that we get a wedge effect, where the cold air from the high is overrun by the warm air aloft. This would tend to keep temperatures cooler than they would otherwise. Then, there’s the question of how far south the cold air will make it. The forecast models don’t agree in terms of exactly what will happen.

Expect tomorrow’s highs to be at least ten degrees cooler than today’s almost 73 degree temperatures (only the second time the temperature has been above 70 since November 15th). Saturday, will be likely to be 15 degrees cooler than that.

The real question is what will we see Saturday and Sunday night. If it’s cold enough, we could see sleet or freezing rain – the Weather service has issued a Special Weather Statement calling for the possibility of a wintry mix, but thinks that the most likely area to be affected is north of a Rome – Roswell – Gainesville line.

So, the best advice I can give you now is to not plan on doing a lot outside over the holiday weekend, and to keep an eye on the weather forecasts, which could likely change as the situation plays out.

Atlanta certainly felt more spring-like today, after the cold air that followed last weekend’s storm was finally replaced by warmer southwesterly breezes. However, cold air continues to come in from Canada, with a doozy likely to hit the Plains states later this week.

The map below shows the GFS forecast for 2 AM on Friday. A low pressure system centered over Cleveland, Ohio is spreading between 1/2 and 1 inch of precipitation over Ohio, Indiana, and Michigan, most likely as between 5 and 10 inches of snow. Meanwhile an extremely high pressure dome is located over Alberta, Canada. The 1056 MB of pressure (highlighted with the arrow) is the equivalent of 31.18 inches of mercury — something you don’t see very often, and indicative of very low temperatures. In the plains, temperatures will probably drop well below zero.

Fortunately for those of us in Georgia, we’re not going to see much of a temperature drop. Because the low is going to remain to our north, we’ll see a return to highs in the low 50s and lows around freezing this weekend, followed by seasonable temperatures for the week of President’s Day. The long range forecasts call for normal temperatures and normal to above normal rainfall through the end of the month.

Signs are beginning to point towards the cold wave we’ve seen since late last week ending by President’s Day. Since the beginning of the month, upper air patterns have allowed colder Canadian air to infiltrate the Southeast, bringing an end to the warmer than normal weather we saw in January. The primary culprit has been a trough of low pressure over the Eastern seaboard.

Essentially, this is the opposite of what we had in January, when a ridge over the east coast kept temperatures warm. So far in February, we are 3.6 degrees colder, on average, than we were last month, although that’s still 1.7 degrees above normal.

Forecast models are predicting that the trough will move out by February 17th or so, allowing warmer Gulf Coast air to come back in, and raise afternoon temperatures back into the 60 degree range, and keep overnight lows above freezing. In addition, it looks like the Arctic Oscillation is moving towards the positive configuration we saw for most of January.

Of course, the models initially predicted that we would have the current cold spell sometime in late January, rather than what actually happened, and they could be wrong again. But, at least for the moment, the Climate Prediction Center says we have equal chances of above or normal temperatures from February 15th through the 21st, when our normal high should be 56 degrees.

On another note, the winter weather predicted for Monday turned out to be a bust. Forecasts of 1 to 3 inches of snow ended up with about an inch of cold rain. You had to go to Gilmer or Union Counties in North Georgia to see an inch of snow. The close in counties to metro Atlanta got just rain, while the northern metro saw a bit of sleet, but that was about it.

While it will be cold enough for snow over the next few days, the storms predicted for Wednesday night and Friday night are unlikely to have enough moisture to work with to do anything significant. As is typical, when cold blasts come out of the north, they can’t take advantage of Gulf moisture to produce any real snow.

The Weather Service is trying to get a handle on the winter weather we are likely to have on Monday. As of this afternoon, they have issued a winter storm warning for Hall County westward towards Rome, and a winter weather advisory for a narrow tier of counties just south of this area, including Gwinnett, DeKalb, Fulton, and Cobb.

The map to the right illustrates the expected weather for 10 AM on Monday. Snow is expected for most of Northwest Georgia, including portions of Gwinnett. South, a mix of rain and snow is predicted. The Weather Service’s Point forecasts, which predicts weather down to a five mile radius of a given point, says that Lawrenceville, Duluth, Buford, and even up towards Gainesville can expect 1 to 3 inches of snow during the day, with a possible additional inch Monday night. However, Snellville gets 1 to 2 inches, and Loganville gets less than an inch.

Much of the uncertainty in predicting this storm (in addition to the Atlanta metro area typically being on the edge of the rain/snow line) is because the precipitation associated with the storm hasn’t even started yet. A low pressure system over the Oklahoma/Texas border is sending a short wave into Alabama and Georgia beginning after dark. So, unlike some of the rain events we’ve had recently, where you can see the storm tracking across the country, this one is shown only on the computer models.

Even if this storm turns out to be a bust, there are several more chances this week for wintry weather. Additional precipitation could pass over the area on Thursday, again on Saturday, and again on Monday the 13th, and each storm has the possibility of wintry weather with it.

As predicted for the last few weeks, winter is making its presence known, beginning this weekend. A cold front associated with a low pressure system in Illinois passed through the Atlanta area this morning, dropping temperatures from 59 to 43 degrees in the three hours between 4 and 7 AM.

Detroit, home of this year’s Super Bowl, is also feeling the effects of this system. They have a winter storm warning out for tonight, with up to a foot of snow expected. That will be over with by game time tomorrow, however 20-25 mile winds and temperatures in the mid-teens will make travel to and from the game more difficult.

The Atlanta area could see some wintry weather by Monday morning as well. The area is under a weather advisory, although no winter storm warning has been issued yet. After a clear but cold day tomorrow, precipitation will begin to come into our area overnight, and early Monday morning. Cold upper air indicates the possibility of snow north of a Rome to Gainesville line, and a snow/rain mix as far south as I-20.

Because the timing of the storm is somewhat up in the air, the forecast is subject to change, but no matter what happens, we are definitely back in a winter pattern, compared to what we saw in January. The coldest of the weather will probably be in the next ten days, with conditions turning warmer and dryer as we approach President’s day.

In case you’re wondering where the cold weather has been during January, take a look at the map below:

The map was created by NASA, and shows the worldwide temperature difference from normal for the first 24 days of January. As you can see, North America remained warm, while much of Europe and Russia was extremely cold. You can blame the jet stream, which largely stayed to the north of the US, while dropping low in Europe. Read more about it (and download a much larger image) at the NASA Earth Observatory website.

No one will be able to argue that we had a normal January. Throughout the entire country, with the exception of southern Florida, temperatures ranged well above normal, as evidenced by the map below, courtesy of the Climate Prediction Center:

While temperatures here in north Georgia were anywhere from 6 to 8 degrees above normal (I recorded a mean January temperature of 48.3 degrees, compared to the Atlanta Airport normal of 42.7 — Atlanta recorded an even warmer average temperatures, with 49.5), the real extraordinary relative warmth was in the upper Plains states, which recorded mean temperatures in the 30s, 15 to 16 degrees above their normals.

If you believe the Weather Service, though, February may turn out to be Februgly after all. After predicting warmer than normal temperatures in its initial forecast back on January 19th, today’s revised forecast calls for a 40% chance of below normal temperatures for the month:

The precipitation forecast also calls for a 33% chance of above normal precipitation, about the same as what was predicted in the earlier forecast. Keep in mind, though that the average February high temperature is 56 degrees, so a colder than normal forecast doesn’t mean as much as it would in January.

As January prepares to end, people all over the country are wondering, “Where is Winter?” Temperatures continue to be much warmer than normal, and despite several model predictions and teleconnections, not much has changed in the weather since the beginning of the month. We continue to see a largely zonal air flow from the Pacific, combined with a heat ridge over the Atlantic that is keeping much of the East in a springlike pattern.

If you believe the models, all of this is going to come to an end beginning in the middle of next week. Here is the National Weather Service 8 to 14 day outlook for the period between February 7th and 13th:

The predicted pattern of colder than normal temperatures in the east, and warmer than normal temperatures in the west (plus warm in Alaska, which isn’t on this map), match the typical negative Arctic Oscillation and North Atlantic Oscillation teleconnection cycles. However, both these signals seem to have bottomed out, and are rising again. The forecast models also haven’t been particularly reliable this winter either.

So, we’ll have to wait and see. Expect warm weather this week, with temperatures in the low 60s, with a chance of a storm on Thursday. As we’ve seen this season, temps will be a little lower following each storm, but will rebound quickly. For next week, if the forecasts verify, we’ll see highs in the upper 40s, which is about 5 degrees colder than normal for the second week in February.

I had a chance to get down to the WeatherFest at the World Congress Center on Sunday, and met several prominent meteorologists, including Paul Kocin, the winter weather expert at the Weather Channel and Max Mayfield, Director of the National Hurricane Center, who assured me that last year’s hurricanes had nothing to do with global warming.

I also had a chance to speak to Elliot Abrams, Chief Forecaster for Accuweather. I listened as he explained how a change in the polar vortex at 10 MB of pressure should cause the polar jetstream to move south. Such a change has occurred within the last week or so, but as Elliot was the first to admit, he’ll be the first to chuck the theory if it doesn’t get cold soon.