The rain that fell on North Georgia yesterday gave way to winter-like conditions on Sunday, with gusty winds, and even some snow flurries reported as far south as Lawrenceville. Yesterday’s predicted rainfall didn’t meet NWS estimates, with just over an inch of rain in Atlanta, and 1.25 inches here in Lawrenceville.

As the front passed following the rain, temperatures dropped, and the winds picked up. This is one case where I regret that my weather station is located at the bottom of a hill in a woody area — I don’t get accurate wind gauge readings. While I recorded wind speeds as high as 17 MPH, I’m sure that they were much higher, judging what I saw with the swaying trees, and debris on the ground.

While Atlantans may by ruing the second winter-like weekend in a row, the storm that came through yesterday is now causing major problems in the Northeast. The Syracuse area is expecting up to a foot of snow overnight, and the winds that have affected us will cause whiteout conditions throughout much of New England over the next day or two.

Meanwhile, closer to the Atlantic, they are expecting floods and high winds in Boston, and in Maine, they have already had more than a foot of snow, with more expected.

I’ve mentioned to some folks I’ve talked to that March and April seem to have been reversed this year, and it looks like that will hold true for the rest of the month. We’re likely to see low temperatures in the 40s for at least the next week or so, with normal lows around 50.

There may be good news on the way, however. The 6-10 day and 8-14 day long range outlooks issued today call for above normal temperatures and rainfall for Georgia. However, the weekend outlooks are computer generated, and don’t reflect the experience of the weather service forecasters. It will be interesting to see if the same outlook holds true Monday, when the humans are back at work.

Much of the eastern half of the country has experienced unusually warm weather so far this winter. New York City finally saw its first flakes of snow this week–the latest first snowfall ever recorded. Temperatures in North Georgia so far this month are between seven and eight degrees above normal. This weekend, the Atlanta area could see temperatures around 70 degrees. Newspapers have run articles lamenting poor sales of winter coats and snow blowers.

If you’re thinking that it’s time to sharpen your lawnmower blades and get out the gardening gloves, you would most likely be wrong.

The split-flow upper air pattern that has been keeping the cold air up in Canada has begun to change, and at least one prominent meteorologist thinks that we could be seeing one of the coldest 30 day periods in the last 50 years.

Accuweather put out a press release on Monday featuring comments from forecaster Joe Bastardi. Bastardi says “the mild weather we’re experiencing now will be a distant memory,” and notes cold air will be moving across the country the week of the 15th, and a cold weather pattern will dominate the second half of the month.

The central part of the country is seeing this change now, and they are going to have a long slog this weekend. A slow-moving front stretches from East Texas to Maine, and is the dividing line between cold and warm air. It’s also bringing a lot of precipitation, as snow in the north and west, and as rain in areas stretching from Louisiana through southern Ohio. In between there’s going to be a major ice storm stretching from the Texas-Oklahoma panhandle through parts of Illinois, Indiana and Ohio. Once all of this moves through by the middle of next week, the cold air will settle in.

Georgia is likely to miss all the weather excitement, at least through Monday evening. By that time, we may see some rain as the front exits the area, and the real cold air will stay out of the way for a few more days. But, by the week of the 22nd, we could see highs only in the mid 40s, and lows in the low 20s; much colder than normal.

With temperatures recorded at Hartsfield Airport in Atlanta 4.5 degrees above normal for December as a whole, and 8.9 degrees above normal for the first six days of January, one could be forgiven for asking, “What happened to Winter?”

Even Mother Nature seems confused. Looking around the yard, I have a few daffodils blooming, the Lenten Roses have bloomed, and I even see that the Daphne is beginning to bloom. On Ronald Reagan Parkway, the Pussy Willows are coming out. All of this is about a month ahead of schedule. In New York City, the entire month of December went without any measurable snowfall–the first time that has happened since recordkeeping began.

The US has been in what’s called a split flow jet stream pattern for the last month or so, with the northern jet stream moving west to east across the northern states, and the southern jet stream moving across the southern states. The effect of this is to keep all the cold Canadian air north of the border, and to bring fronts across the Gulf of Mexico, which is what we saw with the Christmas Day storms, which brought tornadoes to central Florida, and yesterday’s storm, where a violent squall line brought an F1 tornado to the McDonough area, and rain across much of Georgia around lunchtime.

This benign weather pattern will break down by the Saturday the 13th, bringing cold air out of Canada initially into the Plains states, and then moving further east. For the week of January 15th, the Atlanta area will be lucky to see high temperatures of 50 degrees. Beyond then, we’ll likely see more typical winter weather through February.

Before then, we’re going to get two storms. Rain tomorrow could bring 1.5 inches to the area, as a front will stall over Georgia during the day. Things clear out for the work week, with somewhat lower but still relatively warm temperatures and nice weather until next weekend, when another front ahead of the colder air again brings the possibility of rainfall.

So, if your outdoor plants seem a bit overeager, don’t worry too much. There will be plenty of colder weather to slow them down.

Metro Atlanta is battening down the hatches this evening in preparation for the coldest weather yet this season. Radio stations have opened up their storm centers, even though except for the relatively high winds, there’s no storm in sight. Actually, I like Walter Reeves advice the best: turn off your automatic sprinkler systems so you don’t wake up to a sheet of ice for the next few mornings.

Cold weather in December isn’t all that unusual. In 2005, temperatures got down to 20 degrees just before Christmas, and in 2004, it was 17 degrees on December 20th. Those temperatures are comparable to what I expect we’ll see over the next few mornings.

If you’re not a fan of the colder weather, the good news is that once this spell is over, we’re likely to see a warmer period that could last almost through Christmas Day. By Monday, temperatures will moderate with highs in the upper 50s, and lows in the 30s. The following week, we could even see highs in the upper 60s, and lows in the 40s. The warmer weather is also likely to bring us some rain during the period as well.

I spent the day upgrading the website, adding some new maps, and hopefully making it easier to use. Now that winter is in full swing, I’ve added a new Winter Weather page which shows maps of snowfall levels and predicted snowfall for the next 24 hours. There’s also a discussion of major snow and ice storms expected over the next few days.

I’ve also modified the home page to add some additional forecast maps, and to make the maps easier to use. Now, you can click on a tab to see warnings and radar, temperature and precipitation forecasts, and current conditions. I’ve got a little more work to do to finish everything up, especially when trying to display a larger map of some of the forecasts, but it should be done by the end of the weekend.

Temperatures for the past three days have been 15 degrees cooler than normal, on average, bringing us temperatures below freezing, if only briefly, yesterday morning. Fir the month so far, the mean temperature here of 59.8 degrees is four degrees cooler than what would be expected in Atlanta (which has its heat island), and 1.5 degrees cooler than what would be expected in Athens.

The cool spell has ended, however, and is going to be replaced with rain through Saturday morning. The remnants of Hurricane Paul, which made landfall in Mexico yesterday, are moving east, and will bring us between two and four inches of rain over the next two days. The map to the right shows the expected rainfall amounts between now and 8 AM on Saturday.

We can use the rain, since we have had less than half of the precipitation that would be expected for October. It’s interesting to note that despite the perceived lack of tropical weather this season, both this storm and the rainmaker back on October 17th that provided the month’s only other significant precipitation are the result of tropical systems. Once the system clears out on Saturday, expect pleasant late October weather through the end of the week.

This weekend marks the annual change of the clocks back to standard time. The latest sunrise of the year is on Saturday, at 7:52 AM, later than the midwinter sunrise time of 7:42 in early January. This will change next year, however. Instead of moving to daylight time the first Sunday in April, we’ll spring forward on March 11th, the second Sunday in March, and the sun will rise at about the same time it is now. Also next year, we’ll wait until after Halloween to change the clocks back, making the switch on the first Sunday in November. That will push the sunrise to 7:58 AM.