We’re about to get some unusual weather, starting tonight, when a low pressure system in Indiana causes a cold front to pass through the Atlanta area. There’s a chance of thunderstorms, however since it didn’t get as warm today as initially forecast, they are not likely to be severe.

Monday and Tuesday bring the return of Old Man Winter. After a blustery day on Monday, temperatures will drop towards the freezing mark Monday night, with a chance of light snow. Right now, the thinking is that with the wind and precipitation, temperatures won’t drop below freezing, and if they do, it will only be for a short time.

The real risk of a late winter freeze comes Tuesday evening. Tuesday promises to be a colder version of Monday, with continued windy weather and a chance of rain early. By Tuesday evening, the rain, if any will diminish, and clear skies mean the chances for a freeze improve.

Will the freeze be as bad as the Easter Freeze of 2007? In checking various forecasts, I see predictions all over the map, from staying above freezing both nights to lows in the mid-20s Tuesday night. The forecast is complicated by the chance of rain, the winds, and the timing of the front’s movement. Everyone agrees that on Wednesday, we’ll begin to see a warming trend. Reviewing the Easter Freeze two years ago, we had temperatures below 30 degrees two days in a row, with temperatures below freezing for eight hours on the seventh. As you may recall, this caused lots of damage to the azaleas and spring flora. In addition, a warm March–four degrees warmer on average than March, 2009–caused more plants to be in bloom than what we’re seeing now. I’m hoping that the freeze won’t be that bad this year.

This week brings that little golf tournament two hours down the road in Augusta. Just like with the possible freeze this week, the Masters may or may not squeak by with good weather. Playing the practice rounds on Monday and Tuesday will be a challenge for golfers and spectators alike, with windy conditions, highs in the 50s and a chance of rain. will Augusta is more likely to get some rain Sunday night, meaning that the greens won’t be as fast in the practice rounds as Billy Payne might like.

By the time of the Par 3 tournament on Wednesday, temperatures will have warmed up and the winds will have died down somewhat. Practice may be delayed somewhat on Wednesday due to cold weather and frost. Temperatures could drop to the upper 20s, which would mean bad news for Augusta National’s famous azaleas.

Thursday should bring in great weather for the first round of competition, with highs in the mid 70s. However, the next upper trough could bring more rain sometime Thursday night or Friday. This system is moving slower than what was predicted a few days ago, when it was going to pass during the day Thursday. With any luck, it will move through overnight Thursday, otherwise we could have a rain delay on Friday morning.

The final two rounds should be OK, in advance of yet another system which at this time isn’t expected to move in until Monday the 13th. However, with a weather pattern as unsettled as this one is, things could change. Let’s hope for the best, which would be no freeze damage early in the week, and dry weather to follow, at least until the Masters is over.

The Atlanta area saw its first snowfall in over a year on Sunday as March roared in like the proverbial lion. Precipitation changed from rain to snow around noon, and the snow continued to fall until around dark. Unfortunately for snow lovers, the already wet ground and warm soil temperatures meant that much of the snow didn’t stick, although it was enough to close most Atlanta area schools this morning.

Georgia snow totals from the storm include:
Atlanta: 4.2 inches
Athens: 6.5 inches
Columbus: 6.5 inches
Macon: 1.0 inches
Gwinnett County: 5.0 inches
Cobb County: 1.5 inches
DeKalb County: 1.5 inches
Henry County: 3.0 inches
Madison County: 7.0 inches

The greatest measured snow total was in Madison county, northeast of Athens.

The storm moved north overnight, bringing similar amounts of snow to major cities on the east coast:
Charlotte, NC: 6.0 inches
Arlington, VA: 8.0 inches
Baltimore, MD: 5.1 inches
Philadelphia, PA: 5.3 inches
Atlantic City, NJ: 6.8 inches
New York, NY: 7.0 inches
Bridgeport, CT: 8 inches

The weekend’s rain raised the water level on Lake Lanier from 1056.9 feet to 1057.7 feet, with a further increase likely as the snow melts. Atlanta is still short of normal rainfall by 2.5 inches — almost identical to where we were on the first of March in 2008.

While temperatures will be about 20 degrees below normal today and 15 degrees below normal tomorrow, in typical March fashion, we’re in for a big change after that. A warming trend will bring high temperatures to around 70 degrees by this weekend. So, get out and enjoy the snow today, while it lasts.

For the last hour or so it’s been snowing in Lawrenceville. Big, heavy white flakes continue to fall, causing some of the shrubs to bend over as if it was ice. With the temperature having dropped to 33 degrees, the snow is beginning to stick on the grass and cold cars, however it’s turning to slush on roads, walks and driveways.

A picture from a little while ago shows the snow in my backyard:

Looking at the radar, it looks like the heaviest precipitation is falling in the metro Atlanta area. The back end of the snow appears to be along the Georgia/Alabama line, so I don’t know how long it will last. Update: The weather service has issued a winter storm warning for much of north central Georgia, including the metro Atlanta area through midnight tonight. They say we could get an additional two inches of snow. If this is true and tonight’s low temperatures drop into the 20s as expected, it could be nasty in the morning.

The real threat, of course, is not here in Georgia, but further north, from DC to New England, as this storm, combined with the one that pulled through yesterday could be one of the worst of the season as it passes through tonight and Monday.

I’ll post more updates later, but feel free to comment on the snow in your area.

There’s a reasonable chance that this weekend’s spell of wet weather could end up producing a few inches of snow before it’s all over Sunday night. While the Weather Service forecast from this morning hasn’t mentioned it yet, WSB TV has put out a report calling for between two and four inches of the white stuff on Sunday. I heard Kirk Melhuish mention the possibility of snow while driving around at lunch time, and Accuweather is calling for just over an inch in Atlanta on Sunday.

I guess it’s just a question of whether you trust the computer models or not. The HPC is indicating that there is a 40% chance of four inches of snow in much of eastern Georgia (Athens to Augusta), and a 10% chance further west, including Atlanta. If it does happen, it will be unusual. Typically, when temperatures cold enough to support snow come in, the cold front preceding it has moved most of the precipitation out of the area. If the models are right, the precipitation will last long enough to support some snow.

We’ll know more by tomorrow afternoon — still with plenty enough time to run to the store and stock up on bread and milk.

While the last two weeks have been relatively quiet weather-wise in Atlanta, that certainly hasn’t been the case elsewhere in the country. a massive storm earlier this week brought snow, then ice, then more snow to a wide area from Arkansas to Pennsylvania, with Kentucky perhaps suffering the most. State officials there are calling the power outage caused by the ice storm the worst in the state’s history. Chicago has had six or more inches of snow on the ground for the last 20 days, a top ten record, and as of yesterday is recording its third coldest January on record, with a mean temperature of 15.8 degrees, more than six degrees below normal.

Despite a general impression of a cold January in Atlanta, it’s actually been warmer than normal. At Hartsfield, the mean temperature through today is 44 degrees, 1.3 above normal. It’s been a bit cooler here in Lawrenceville, with a mean of 42.5 degrees, but that’s to be expected. The January mean temperature in 2008 was actually over a degree cooler than this year, although 2007 and 2006 were both above normal.

After this weekend, which could be quite pleasant, we have the threat of the worst storm of the winter season. The eyes of the weather world are focusing on Monday and Tuesday, when a powerful storm will start in the southeast and move north, bringing a chance of snow to North Georgia, and likely a doozy of a storm to the mid-Atlantic states.

Most of the country’s weather this winter has been affected by the northern branch of the jet stream. In essence, the northern branch divides cold Canadian air from the (slighly warmer) air to the south. It can dive south, as we saw mid-month when we got the coldest temperatures of the season. For the first time this winter, the southern branch is also active as well. The southern branch divides warmer, tropical air to the south and the colder air to the north. When these two branches join back up, you have a good possibility of wintry weather.

The forecast models have been changing from run to run on the position of the two jet streams, and where the snow will fall, but there is a definite possibility that Atlanta could see some wintry weather on Monday or Monday night. In the worst-case scenario, we could see something like what happened in March, 1993, when the Atlanta area got over a foot of snow. Or, we could get just rain, and not much rainfall at that. Keep your eyes on the forecast over the weekend to get updates.

The History of the Global Warming Argument

The founder of the Weather Channel, John Coleman, has published a blog entry describing the history of the global warming (or climate change, to use the current PC term) debate. Coleman says there is no basis for the climate change threat, which he argues was blown way out of proportion because a researcher was looking for more government funding.

This morning, I recorded a low of 13.5 degrees at my home near Brookwood High School. That’s the lowest temperature reading I’ve had since I started keeping records in January of 2002. While that’s mighty cold, it’s not going to match the record of 5 degrees, set on January 16, 1972.

The cold weather stretched across Georgia this morning, with lows of 10 degrees reported in Canton, Chamblee, Dalton, Marietta and Rome, 12 degrees in Atlanta Hartsfield, Canton, Gainesville and Marietta. Elsewhere, it was 14 in Athens, 19 in Columbus, 21 in Macon and 30 degrees in Brunswick.

If we get above 32 degrees today, it won’t be for very long. Saturday morning’s temperatures are going to approach this morning’s lows, but again, it’s not likely to be record-breaking. The record low for January 17th in Atlanta is 0, set in 1982.

Temperatures will begin to rise on Saturday, setting the stage for some possible wintry weather from Saturday night into Sunday. This appears to be a somewhat tricky forecast, since models vary on the amount of moisture available for precipitation. Conditions will be cold enough to support snow, however, so stay tuned as the weekend progresses.

The unusually cold weather hasn’t been confined to Georgia. As the cold air moved across the country this week, a record low ever for Illinois was recorded at 27 below 0. Yesterday’s low temperature was -48 in Garrison, North Dakota.

No matter where you look, it seems like it’s just plain cold outside. Take a look at the low temperatures recorded in Europe last night, for example:

The cold snap there has caused the airport to close in Madrid, Spain, and snow in Milan Italy disrupted activity in that city. It was 13 below zero in Germany and Poland. Paris France recorded its coldest night in 12 years. The situation is being made more dire by the fact that there is limited natural gas for heating, after Russia limited distribution through Ukraine.

Now, take a look at Canada:

All that cold Canadian air is going to move south over the next few days, setting the stage for record low temperatures in the United States, which could last through Martin Luther King Day. Residents in a wide band from Chicago to New England are likely to see the brunt of the cold, made worse because the remnants of snowstorm this weekend are unlikely to melt. By next Thursday, the high in Chicago, Illinois could be zero, with a low of about five below, according to forecasts. In Cleveland, Ohio, it’s not likely to break 20 degrees from Wednesday through Friday. As the arctic air moves east, New York may not make it above 15 degrees on Friday.

Here in Georgia, it’s going to be a bit more moderate, although highs later this week may not make it above 40, with lows around 20. Since the coldest of the weather is almost a week away, forecast temperatures are largely derived from computer modeling. But, even if the temperature predictions are slightly too high or too low, next week could be one for the record books.

On a side note, Lake Lanier has risen about 2.5 feet since the start of this week’s rain. That’s good news for the drought, Let’s hope that the cold weather doesn’t keep the rain away as it usually does, because we still need more rain.

Last week’s rainfall greatly reduced the intensity of the drought in Georgia, according to the latest update to the drought monitor, shown at right. Before last week’s rain, exceptional drought was the rule north and east of Gwinnett County, some 11% of the state. This week, no part of Georgia is in exceptional drought, and almost 70% of the state is drought free.

Only a small area of the state between Savannah and Brunswick increased in its rain deficit, going from normal to exceptionally dry. The newest outlook through March, 2009 calls for continued improvement for drought conditions in the southeast, and for drought to develop in the Florida peninsula and extend in Texas.

The updated drought outlook doesn’t square well with the latest long range outlooks from the Climate Prediction Center, released this morning. The temperature outlook for January is for warmer than normal east of the Rocky Mountains, except for South Georgia and Florida, which could be colder or warmer than normal. Below normal precipitation will occur south and east of a line from southern Louisiana to eastern North Carolina, more or less south of I-85.

For the first three months of the new year, warmer than normal temperatures are predicted east and south of a line from New Mexico to Wisconsin. Colder than normal temps are in line for the Pacific Northwest, with the Northeast possibly going either way. The three month rainfall outlook calls for above normal precipitation in the Ohio Valley, and below normal rain in the southeast.

Snow in Las Vegas

This has certainly been a month where snow has turned up in places you wouldn’t expect it to, and in record amounts. In addition to snow in Houston and New Orleans earlier this month, yesterday brought record snow to Las Vegas, Nevada. “Las Vegas Hits the Jackpot,” trumpeted the Weather Service’s record event report for Wednesday. The Las Vegas Weather Service office reported 3.6 inches of snow, the most ever in December, and the 8th worst snowstorm since recordkeeping began in 1937. Up to 7 inches of snow was measured in suburban Henderson, Nevada. In California, 5 inches of snow was measured in Boulevard, which is in interior San Diego County, and up to 20 inches of snow fell in the mountains to the east of Los Angeles. A light dusting was even reported in Malibu.

While Atlanta basks in what could be near-record temperatures today and Friday, the snow will continue to move north and east, setting the stage for a possible white Christmas, but not here.

Temperatures across the Southeast remained colder than normal in November, and Georgia recorded its 27th wettest November out of 114, unfortunately with most of the rain in the southern part of the state. For the entire United States, it was the 10th warmest and 41st driest November since recordkeeping began back in 1895, according to the National Climate Data Center.

Most of the above normal temperatures were in the west, with nine states from Colorado to California having top 10 warm Novembers, and five states having top 5 warm Novembers. Because of the trough that sat over the eastern half of the country for most of the month, most of the states east of the Mississippi were colder than normal, with Georgia and South Carolina experiencing top 10 (or should that be bottom 10) coldest Novembers.

Only North Dakota had a top ten wettest November, with most of the country having about normal rainfall. However, the Midwest and South had their 27th and 28th driest November on record.

Of course, the cold November weather in the Southeast doesn’t compare to what’s going on now in the plains states. This morning’s low was 33 degrees below zero in Havre, Montana, the coldest spot in the country. The western trough is bringing Siberian air to much of the country, as you can see by looking at the US temperatures early this evening;

A strong cold front is running along the Mississippi and Ohio rivers, with locations to the east much warmer than those to the west. Yesterday, Denver recorded a new record low for the date of 18 below zero. The previous low record was -14, set in 1901. Fortunately for those of us in the Atlanta area, the front isn’t going to get this far, and we should see warmer than normal temperatures through the end of the week.

Over the weekend, the Climate Prediction Center released its revised December temperature outlook, which looks quite a bit different than the one they released back on November 20th. The old version had warmer than normal conditions predicted for an area centered on Oklahoma and Kansas, while the new one, as you can see below, says it’s going to be warm in the west and cold in the east:

The other possible bit of good news for rain-starved Georgia is that the precipitation outlook has changed as well, with what was a 33% chance of drier than normal weather in the state changing to equal chances of above or below normal rainfall.

The updated temperature outlook brings the Weather Service more in line with what other winter forecasts are saying, and with what the CPC’s 6-10 and 8-14 day outlooks call for, which is for a significant chance of below normal temperatures for most of the US and above normal precipitation for all but the desert southwest from the 7th through the 15th of December.

November certainly provided a good lead in to the cold weather, at least here in Georgia. At Atlanta’s Hartsfield Airport, the average temperature for the month was 50.5 degrees, 2.8 degrees below normal. It was a little cooler out here in the ‘burbs, with my thermometer recording an average temperature of 47.9 degrees. Despite around an inch and a half of rain throughout most of the Atlanta metro area from Friday through Sunday, we ended up with 2.64 inches of rain at Hartsfield, or 64% of normal. Here, I got even less, with 2.7 inches of rain, 1.5 of which we got over the weekend.

November 30th also marked the end of the 2008 hurricane season. It was an above average year, with 16 named storms, eight hurricanes, and five intense hurricanes. Hurricane Ike became the third most expensive hurricane to hit the US, after Katrina and Andrew. Tropical Storm Fay set a record, striking Florida four separate times back in August.